Stationary Engineer Practice Quiz

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| By Mike Jewel
Mike Jewel, Stationary Engineer
Mike, a state and municipally licensed steam and stationary engineer, boasts over 20 years of experience in building trades. His expertise reflects a seasoned professional dedicated to his craft.
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| Attempts: 35,142 | Questions: 190 | Updated: Jun 11, 2026
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1.
  1. In order to permit the water in a hot water heating system to expand without a corresponding increase in pressure, an ______________ _________ must be used.

Explanation

An expansion tank is necessary in a hot water heating system to allow for the expansion of water without causing a rise in pressure. As water is heated, it expands and needs a place to go. The expansion tank provides this space, allowing the water to expand and contract safely without putting excess pressure on the system. This helps to prevent damage to pipes, valves, and other components of the heating system.

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About This Quiz
Stationary Engineer Practice Quiz - Quiz

Do you wish to be a Stationary Engineer? Get ready to take this quiz on Stationary Engineer Class 3 Examination that is here for you. A compendium of questions that should help with any licensing exam. This quiz is going to be educational and interesting as well at the same... see moretime. Would you be able to get a score above 70 on this quiz? You are an expert if you are able to do so. Let's see how well you perform. Best of luck to you! see less

2.

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2.
  1. The _______________ is the heart of the refrigeration system.

Explanation

The compressor is considered the heart of the refrigeration system because it plays a crucial role in the cycle. It is responsible for compressing the refrigerant gas, raising its temperature and pressure. This compressed gas then moves to the condenser where it releases heat and transforms into a high-pressure liquid. Without the compressor, the refrigeration cycle would not be able to function properly as it is responsible for circulating the refrigerant and maintaining the necessary pressure levels.

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3.
  1. In _______________ boilers, the water passes through the tubes, and the products of combustion pass around the tubes.

Explanation

In watertube boilers, the water passes through the tubes, and the products of combustion pass around the tubes. This design allows for efficient heat transfer and faster steam production. The water is contained within the tubes, which are surrounded by hot gases from the combustion process. This arrangement increases the surface area for heat exchange and provides better control over the temperature and pressure of the steam. Watertube boilers are commonly used in power plants and industrial settings where high steam production and efficiency are required.

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4.
  1. A solid that precipitates out of solution and adhere to the boiler heating surfaces is called__________.

Explanation

Scale is the correct answer because it refers to the solid that forms and adheres to the heating surfaces of a boiler. This scale is typically formed when minerals and impurities in the water precipitate out and accumulate over time, reducing the efficiency of the boiler and potentially causing damage.

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5.
  1. The presence of scale on the boiler tubes will result in a _______________ in the boilers efficiency, and an _______________ in the temperature on the boiler tubes.

Explanation

The presence of scale on the boiler tubes will cause a decrease in the boilers efficiency, as the scale acts as an insulator and reduces heat transfer. This decrease in efficiency will result in an increase in the temperature on the boiler tubes, as the heat is not being effectively transferred away.

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6.
  1. A ________ _______ AHU supplies conditioned air to only one area of the building.

Explanation

A Single Zone AHU supplies conditioned air to only one area of the building. This means that the AHU is designed to serve a specific zone or room, and the air flow and temperature can be adjusted for that particular area. This type of AHU is commonly used in small spaces or individual rooms where the conditioning needs may differ from other areas of the building.

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7.
  1. ____________is the bleeding of a portion of the water to remove suspended solids.

Explanation

Blowdown is the process of bleeding a portion of the water to remove suspended solids. This is typically done in industrial settings, such as power plants or boilers, to maintain the quality of the water and prevent buildup of impurities. By removing the suspended solids through blowdown, the water can be kept clean and the equipment can operate more efficiently.

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8.
  1. ______________ is the deterioration of the boiler metal by a chemical reaction.

Explanation

Corrosion is the process in which the boiler metal deteriorates due to a chemical reaction. This reaction can occur when the metal is exposed to oxygen, water, and other corrosive substances, leading to the formation of rust or other corrosive compounds. Corrosion can weaken the metal, causing it to lose its structural integrity and potentially leading to leaks or other failures in the boiler system.

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9.
  1. ______ ________________ are used extensively in pulverized-fuel-burning plants in order to keep heat-absorbing surfaces free from soot and ash buildup.

Explanation

Soot blowers are used extensively in pulverized-fuel-burning plants to keep heat-absorbing surfaces free from soot and ash buildup. Soot and ash can accumulate on these surfaces, reducing their efficiency and potentially causing damage. Soot blowers use high-pressure steam or compressed air to remove the buildup, ensuring that the surfaces remain clean and heat transfer is optimized. This helps to maintain the overall efficiency and performance of the plant.

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10.
  1. When two or more boilers are connected into a common steam header, and each boiler is equipped with a man-hole,_____ stop valves must be used on each boiler.

Explanation

When two or more boilers are connected into a common steam header, and each boiler is equipped with a man-hole, 2 stop valves must be used on each boiler. This is because having 2 stop valves on each boiler provides an additional level of safety and allows for maintenance and repairs to be carried out on one valve while the other valve remains operational. It also helps in isolating the boiler from the common header in case of any emergency or maintenance requirements.

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11.
  1. A 10 x 5x 15 duplex reciprocating pump has a steam cylinder diameter of ____inches, has a water cylinder diameter of _____ inches, and a long stroke of _____inches.

Explanation

The given answer states that the steam cylinder diameter is 10 inches, the water cylinder diameter is 5 inches, and the long stroke is 15 inches. This suggests that the dimensions of the reciprocating pump are such that the steam cylinder has a larger diameter compared to the water cylinder, and the stroke length is longer than the cylinder diameters.

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12.
  1. Sulfur in the soot then unites with moisture from condensation to produce a ____________ ________.

Explanation

When sulfur in the soot combines with moisture from condensation, it forms sulfurous acid. This reaction occurs when the sulfur in the soot reacts with water vapor in the air, resulting in the formation of sulfurous acid. Sulfurous acid is a weak acid that is commonly found in polluted air and can contribute to acid rain.

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13.
  1. A _______________ ____________ air handler unit operates at the rated capacity at all times.

Explanation

A constant volume air handler unit operates at the rated capacity at all times, meaning that it consistently delivers a fixed volume of air. This type of air handler unit is typically used in buildings where the air conditioning or heating requirements do not vary significantly throughout the day or year. The unit's fan runs at a constant speed, providing a consistent airflow and temperature to the space it serves. This design is often more energy-efficient and easier to control compared to variable volume air handler units, which can adjust their airflow based on demand.

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14.
  1. ___________ deflect the hot gases back and forth between the tubes a number of times to enable greater heat absorption by the boiler tubes.

Explanation

Baffles are used to deflect the hot gases back and forth between the tubes in order to increase the heat absorption by the boiler tubes. They create a zigzag pattern for the gases, ensuring that they come into contact with the tubes multiple times. This increases the efficiency of heat transfer and allows for greater heat absorption by the boiler tubes.

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15.
  1. A British thermal unit, BTU, is the amount of heat that need to raise the temperature on one ___________ of water one _________ _______________.

Explanation

A British thermal unit (BTU) is a unit of measurement used to quantify the amount of heat required to raise the temperature of one pound of water by one degree Fahrenheit.

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16.
  1. The low water fuel cut-off will shut off the fuel to the burner before the water drops below the safe permissible level, and thus prevent ______________ damage to the boiler.

Explanation

The low water fuel cut-off is designed to shut off the fuel supply to the burner when the water level in the boiler drops below a safe level. This prevents overheating of the boiler, which can cause serious damage.

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17.
  1. The _____________ on the refrigeration system absorbs the heat from the space.

Explanation

The evaporator is the component in the refrigeration system that absorbs heat from the space. As the refrigerant passes through the evaporator, it evaporates and absorbs heat from the surrounding air or space, causing the temperature to decrease. This cooled refrigerant is then sent to the compressor to be pressurized and circulated back into the system.

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18.
  1. A _________ _______AHU has heating and cooling coils located at the different zones. It uses air dampers from the hot and cold ducts to maintain zone comfort.

Explanation

A Multi Zone AHU has heating and cooling coils located at different zones, allowing for individual temperature control in each zone. It uses air dampers from the hot and cold ducts to maintain comfort in each zone. This type of AHU is ideal for buildings with multiple areas that require different temperature settings.

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19.
  1. The hot gases from the furnace pass into a blank lined combustion chamber on a dry back scotch marine boiler.

Explanation

In a dry back scotch marine boiler, the hot gases from the furnace enter a combustion chamber. This combustion chamber is lined with refractory material. Refractory is a type of heat-resistant material that can withstand high temperatures without melting or deforming. It is used in boilers to protect the surrounding structure from the extreme heat generated by the combustion process. The refractory lining helps to maintain the efficiency and durability of the boiler by preventing heat loss and minimizing damage to the surrounding components.

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20.
  1. Cogeneration plants sell ____________ to the local industrial plants, and _____________ to the local __________.

Explanation

Cogeneration plants sell steam and electricity to the local utilities.

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21.
  1. A dry pipe on a Scotch Marine Boiler is used to remove _____________ from the steam prior to leaving the boiler.

Explanation

A dry pipe on a Scotch Marine Boiler is used to remove moisture from the steam prior to leaving the boiler. This is important because excessive moisture in the steam can cause damage to the piping system and reduce the efficiency of the boiler. By removing moisture, the dry pipe helps to ensure that the steam is dry and of high quality, which is necessary for various industrial processes.

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22.
  1. The color of Cylinder containing R -22 is ___________ ________ before 2020.

Explanation

The color of the cylinder containing R-22 is light green before 2020.

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23.
  1. The lowest visible water level in the gauge glass is ___ above the top of the boiler tubes on a scotch marine boiler.

Explanation

The lowest visible water level in the gauge glass is 2" above the top of the boiler tubes on a scotch marine boiler. This is important because it ensures that there is enough water in the boiler to prevent overheating and damage to the tubes. It also allows for proper monitoring and maintenance of the water level in the boiler.

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24. The presence of elevated levels of ______ in the fuel gas is an indication of incomplete combustion.

Explanation

Carbon monoxide is produced during incomplete combustion, where there is insufficient oxygen available to fully burn the fuel. The presence of carbon monoxide in the flue gas is therefore an indication that the combustion process was not complete. Incomplete combustion can lead to the release of harmful pollutants and can also result in lower energy efficiency.

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25.
  1. ______________ BTU's per hour output is one boiler horsepower.

Explanation

One boiler horsepower is equivalent to 33,475 BTU's per hour output.

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26.
  1. A _______________ is a U-tube draft gauge to measure the differential pressure between two points.

Explanation

A manometer is a U-tube draft gauge used to measure the differential pressure between two points. It consists of a U-shaped tube partially filled with a liquid, such as mercury or water. The pressure difference between the two points causes the liquid to rise or fall in one side of the tube, indicating the pressure difference. Manometers are commonly used in various applications, such as measuring gas pressure, airflow, and fluid levels.

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27.
  1. When using a lift lever to manually test a safety valve, the boiler pressure must be at least _____ percent of the safety valve setpoint.

Explanation

When using a lift lever to manually test a safety valve, the boiler pressure must be at least 75 percent of the safety valve setpoint. This is because the lift lever test is performed to ensure that the safety valve is functioning properly and can relieve excess pressure in the boiler. By testing at 75 percent of the setpoint, it ensures that the safety valve will open and relieve pressure when it reaches the setpoint, providing a safety measure for the boiler system.

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28.
  1. _______ drum below the rear headers was used to collect sediment and was blown out from time to time.

Explanation

The correct answer is mud. The drum below the rear headers was used to collect sediment, specifically mud, and was blown out from time to time.

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29.
  1. _______________ is when water or impurities leave the boiler with the steam.

Explanation

Carryover is the term used to describe the situation when water or impurities are carried out of the boiler along with the steam. This can happen due to factors such as high steam velocities, inadequate separation equipment, or excessive boiler water levels. Carryover can lead to various problems, including damage to downstream equipment, reduced steam quality, and decreased efficiency of the system.

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30.
  1. In conduction the transfer of heat from one material to another occurs due to direct _________.

Explanation

In conduction, the transfer of heat occurs due to direct contact between two materials. When two objects are in contact, heat energy is transferred from the hotter object to the colder object through molecular collisions. This process continues until both objects reach thermal equilibrium, with the heat evenly distributed between them. Therefore, contact is the correct answer as it accurately describes the mechanism of heat transfer in conduction.

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31.
  1. When the boiler steam pressure reaches setpoint of the main scale of the operating control, the burner will turn _______.

Explanation

When the boiler steam pressure reaches the setpoint of the main scale of the operating control, the burner will turn off. This is because the setpoint is the desired or target pressure, and once it is reached, the burner is no longer needed to generate more steam. Turning off the burner helps to maintain the pressure within the desired range and prevent overpressure in the boiler.

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32.
  1. The modulating control controls the ___________ ________ of the burner.

Explanation

The modulating control is responsible for controlling the firing rate of the burner. It adjusts the amount of fuel being supplied to the burner based on the desired heat output. By regulating the firing rate, the modulating control ensures that the burner operates at the desired level of heat production, allowing for precise temperature control.

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33.
  1. The _____________ on the refrigeration system rejects the heat from the system.

Explanation

The condenser is responsible for rejecting the heat from the refrigeration system. It is a component that helps in the cooling process by transferring heat from the refrigerant to the surrounding environment. This is done by condensing the refrigerant vapor into a liquid state, releasing heat in the process.

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34.
  1. Welding a flat strip of metal between the waterwall tubes is known as ____________ wall construction.

Explanation

Welding a flat strip of metal between the waterwall tubes is known as membrane wall construction. This type of construction involves creating a continuous, sealed membrane of metal that separates the water and steam from the combustion gases in a boiler. The membrane wall helps to improve the efficiency and performance of the boiler by providing a barrier between the two fluids and ensuring proper heat transfer.

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35.
  1. The three classes of feedwater pumps are _______________, _______________, and _____________.

Explanation

The correct answer is "reciprocating, centrifugal, and rotary". These three classes refer to different types of feedwater pumps. Reciprocating pumps use a piston or plunger to create pressure and move the fluid. Centrifugal pumps use centrifugal force to move the fluid and are commonly used in industrial applications. Rotary pumps use rotating mechanisms to move the fluid, such as gears or vanes. Therefore, the correct answer includes all three types of pumps.

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36.
  1. Welding a flat strip of metal between the waterwall tubes is known as _______________wall construction.

Explanation

Welding a flat strip of metal between the waterwall tubes is known as membrane wall construction. This type of construction involves creating a continuous, sealed membrane of metal that separates the water and steam from the combustion gases in a boiler. The membrane wall construction helps to improve the efficiency and safety of the boiler by providing a strong and reliable barrier between the different components.

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37.
  1. The minimum size of the piping between the boiler and the water column is____.

Explanation

The minimum size of the piping between the boiler and the water column is 1".

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38.
  1. Fire tube boilers are likely to leak due to cracking, burning and corrosion of the _________ _________.

Explanation

Fire tube boilers are likely to leak due to cracking, burning, and corrosion of the tube ends. The tube ends are the parts of the boiler where the tubes connect to the boiler shell. Over time, the intense heat and pressure in the boiler can cause the tube ends to become weakened and damaged. This can lead to cracks, burning, and corrosion, which can result in leaks in the boiler. Regular maintenance and inspection of the tube ends are necessary to prevent these issues and ensure the safe and efficient operation of the boiler.

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39.
  1. The test most commonly used for determining wall thickness of pipes or flat plate is an ___________________ test.

Explanation

The test most commonly used for determining wall thickness of pipes or flat plate is an ultrasonic test. Ultrasonic testing involves the use of high-frequency sound waves to detect internal flaws or measure the thickness of materials. It is a non-destructive testing method that is often used in industries such as oil and gas, manufacturing, and construction to ensure the integrity and safety of structures and equipment.

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40.
  1. _____ ______ are a potential source of oil contamination of the water side of a boiler.

Explanation

Oil heaters are a potential source of oil contamination of the water side of a boiler. This is because oil heaters are used to heat oil, and if there is any leakage or malfunction in the oil heating system, it can result in oil entering the water side of the boiler. This can lead to contamination of the boiler water, which can negatively impact the efficiency and performance of the boiler. Therefore, it is important to regularly inspect and maintain oil heaters to prevent any oil contamination issues.

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41.
  1. The two types of electric boilers are _______________ and ______________.

Explanation

The correct answer is resistance & electrode. Electric boilers can be categorized into two types based on their heating elements: resistance and electrode. Resistance boilers use electrical resistance to generate heat, while electrode boilers use electric current passing through water to produce heat.

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42.
  1. A device used to reduce the temperature of superheated steam to a lower desired temperature is a _______________________.

Explanation

A desuperheater is a device used to reduce the temperature of superheated steam to a lower desired temperature. It achieves this by injecting a coolant or a liquid into the superheated steam, which absorbs the excess heat and cools down the steam. This process is commonly used in industrial applications where the temperature of the steam needs to be controlled for various purposes, such as preventing damage to equipment or improving the efficiency of a system.

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43.
  1. A solution is said to be ______________ when it can no longer dissolve anymore impurities.

Explanation

A solution is said to be saturated when it has reached its maximum capacity to dissolve any more impurities. In other words, it cannot dissolve any additional solute at a given temperature and pressure.

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44.
  1. The flow of heat through electromagnetic waves is known as _________________.

Explanation

Radiation is the correct answer because it refers to the flow of heat through electromagnetic waves. Unlike convection and induction, which involve the transfer of heat through physical contact or movement of particles, radiation involves the transfer of heat through electromagnetic waves, such as infrared radiation. Dissonance is unrelated to the flow of heat.

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45.
  1. The accumulation of carbon dioxide in the condensate system produces _____________ __________ , which attacks and corrodes steam metal piping.

Explanation

The accumulation of carbon dioxide in the condensate system leads to the formation of carbonic acid. This acid is highly corrosive and attacks the metal piping used for steam. The corrosion caused by carbonic acid can lead to damage and deterioration of the piping system over time.

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46.
  1. Because the shell of the HRT is exposed to the fire, it requires a careful ___________ ____________ for scale, bulging and blisters.

Explanation

The correct answer is internal inspection. The reason for this is that the shell of the HRT is exposed to the fire, which can cause damage such as scale, bulging, and blisters. To ensure the safety and proper functioning of the HRT, a careful internal inspection is necessary. This inspection allows for the identification of any potential issues or damage that may have occurred due to the exposure to fire. By conducting regular internal inspections, any problems can be addressed and resolved promptly, preventing further damage or potential hazards.

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47.
  1. The _______________ _______________ _________ is used to control the amount of blowback on the safety valve.

Explanation

The blowback adjusting ring is used to control the amount of blowback on the safety valve. This means that it regulates the amount of pressure that is allowed to escape through the safety valve, preventing excessive blowback and ensuring the valve functions properly. By adjusting the blowback adjusting ring, the operator can fine-tune the safety valve to maintain the desired pressure level and prevent any potential damage or malfunction.

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48.
  1. The number 4,5 and 6 oils are heavy and viscous, thus require ______________ prior to being sprayed into a furnace.

Explanation

The number 4, 5, and 6 oils are heavy and viscous, which means they are thick and difficult to flow. Therefore, they need to be heated before being sprayed into a furnace. Heating these oils reduces their viscosity and makes them easier to atomize and spray into the furnace.

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49.
  1. _____________ is the replacement for refrigerant R-22.

Explanation

R-410a is the replacement for refrigerant R-22. Refrigerant R-22 is being phased out due to its harmful effects on the ozone layer. R-410a is a more environmentally friendly alternative that does not contribute to ozone depletion. It is commonly used in air conditioning systems as a refrigerant.

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50.
  1. A slow opening blowdown valve must complete _____ turns between full open and full shut.

Explanation

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51.
  1. __________ _________ is the temperature at which fuel oil will give off vapor that will ignite when exposed to an open flame.

Explanation

The flash point is the temperature at which fuel oil will give off vapor that will ignite when exposed to an open flame.

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52.
  1. In an open feedwater heater, steam and water are in __________ _____________.

Explanation

In an open feedwater heater, steam and water are in direct contact. This means that the steam and water come into direct physical contact with each other, allowing for efficient heat transfer between the two. This direct contact allows the steam to condense and transfer its heat energy to the water, resulting in an increase in the temperature of the water.

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53.
  1. In a ___________ water softener, calcium and magnesium ions are exchanged for sodium ions. The result is a soft salt sludge that can be easily removed by bottom blowdown.

Explanation

In a zeolite water softener, calcium and magnesium ions are exchanged for sodium ions. Zeolite is a type of mineral with a porous structure that allows it to trap and exchange ions. When hard water passes through the zeolite resin bed, the calcium and magnesium ions are attracted to the zeolite and are replaced by sodium ions. This process effectively softens the water by reducing the concentration of calcium and magnesium ions. The softened water then flows out of the system, while the calcium and magnesium ions are retained in the zeolite resin bed, forming a soft salt sludge that can be easily removed by bottom blowdown.

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54.
  1. A through stay differs from a diagonal stay in that it runs the ____________ __________ of the boiler.

Explanation

A through stay differs from a diagonal stay in that it runs the entire length of the boiler. This means that the through stay extends from one end of the boiler to the other, providing support and stability along the entire length. In contrast, a diagonal stay may only run diagonally across a portion of the boiler, providing support in a specific area.

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55.
  1. The operation of a black liquor boiler is known for its ________ generation and recovery of _________ _________.

Explanation

The operation of a black liquor boiler is known for its generation and recovery of steam and soda ash. The black liquor, a byproduct of the pulp and paper industry, is burned in the boiler to produce steam, which can be used for various purposes such as power generation or heating. Additionally, the process also helps in recovering soda ash, which is a valuable chemical used in various industrial applications.

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56.
  1. One grain is equal to ________ parts per million.

Explanation

Parts per million (ppm) is a unit used to express the concentration of a substance in a solution. It represents the number of parts of the substance per one million parts of the solution. In this case, one grain is equal to 17.1 parts per million.

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57.
  1. When the boiler water has a high level of solids, steam bubbles can be trapped below the water line, causing water level fluctuation is known as ______________.

Explanation

Foaming is the correct answer because when the boiler water has a high level of solids, steam bubbles can get trapped below the water line, resulting in water level fluctuation. This phenomenon is known as foaming.

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58.
  1. Water hammer is caused by quickly opening a __________ _________. The sudden change in pressure and temperature on the connected piping may cause vibration, noise, or even pipe rupture.

Explanation

Water hammer is caused by quickly opening a steam valve. When a steam valve is rapidly opened, it causes a sudden change in pressure and temperature in the connected piping. This sudden change can lead to vibration, noise, or even pipe rupture.

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59.
  1. When a furnace baffle breaks, the gases short-circuit one or more passes, causing excessive ______   _____  temperature.

Explanation

When a furnace baffle breaks, the gases short-circuit one or more passes, causing excessive flue gas temperature. This means that the baffle, which is designed to direct the flow of gases, is no longer functioning properly. As a result, the gases are not being properly cooled down and are instead reaching higher temperatures. Flue gas refers to the gases that are produced during the combustion process and are released through the flue or chimney.

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60.
  1. A ____________________ pump can be started with the discharge valve shut.

Explanation

A centrifugal pump can be started with the discharge valve shut because it uses centrifugal force to move the fluid. When the pump is started, the impeller spins rapidly, creating a centrifugal force that pushes the fluid towards the outer edges of the impeller. This force allows the fluid to be pushed through the pump even with the discharge valve shut.

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61.
  1. A dual Duct AHU has hot and cold Ducts connected to ___________ _______.

Explanation

A dual Duct AHU has hot and cold Ducts connected to a Mixing Box. The Mixing Box is responsible for mixing the hot and cold air streams to achieve the desired temperature before supplying it to the conditioned space. This allows for precise control over the temperature of the supplied air.

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62.
  1. Scale accumulation on the waterside of a firetube boiler can lead to possible blank and loosining of the tube.

Explanation

Scale accumulation on the waterside of a firetube boiler can lead to overheating. When scale builds up on the boiler tubes, it acts as an insulator, preventing efficient heat transfer. This can cause the tubes to overheat, leading to potential damage and reduced efficiency of the boiler. Overheating can also result in the tubes becoming weakened and more prone to failure, posing a safety risk. Therefore, it is important to regularly clean and remove scale from the waterside of a firetube boiler to prevent overheating and maintain optimal performance.

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63.
  1. A stay that is shorter than 8" and threaded is required to have a blank

Explanation

A stay that is shorter than 8" and threaded is required to have a tell tale hole.

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64.
  1. The pipes connecting the water column to the boiler must be a minimum diameter of ____ inch.

Explanation

The pipes connecting the water column to the boiler must have a minimum diameter of 1 inch. This is necessary to ensure proper flow and pressure of water between the water column and the boiler. A smaller diameter pipe may not be able to handle the required volume of water, leading to inadequate water supply and potentially causing issues with the boiler's operation.

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65.
  1. The operation of a black liquor boiler is known for its __________ generation, and heat recovery of _______ _______.

Explanation

The operation of a black liquor boiler is known for its steam generation, which refers to the production of steam as a result of the boiler's operation. Additionally, the boiler is also known for its heat recovery of soda ash, which means that it is able to recover and utilize the waste heat produced during the process to generate soda ash.

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66.
  1. A cylindrical cup rotating at high speeds is utilized in a _________ _______ burner.

Explanation

A cylindrical cup rotating at high speeds is used in a rotary cup burner. This type of burner is commonly used in industrial applications to efficiently and evenly distribute fuel for combustion. The rotation of the cup creates centrifugal force, causing the fuel to be evenly distributed and atomized, resulting in a more efficient and controlled combustion process.

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67.
  1. One grain is equal to ______ parts per million. _________grains equals one pound.

Explanation

One grain is equal to 17.1 parts per million. Therefore, 7,000 grains equals one pound.

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68.
  1. Too much _______ causes dense, white smoke.

Explanation

When there is too much air present in a combustion process, it can cause incomplete burning of the fuel. This incomplete burning produces dense, white smoke.

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69.
  1. Comparing the mill test report with the markings on the material is a form of ______________ inspection of welding.

Explanation

Comparing the mill test report with the markings on the material is a form of visual inspection of welding. This involves visually examining the material and comparing it with the documented information to ensure that it meets the required specifications and standards. It does not involve any chemical, ultrasonic, or liquid penetrating techniques.

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70.
  1. According to ASME code a HTHW boiler is any boiler that operates above ____________ or ____________.

Explanation

According to the ASME code, a HTHW (High Temperature Hot Water) boiler is defined as a boiler that operates above 160 PSI and 250 degrees Fahrenheit.

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71.
  1. In lieu of a stop valve a ____________ _____may be used instead of the stop valve ___________ to the boiler.

Explanation

A non-return valve may be used instead of a stop valve that is closest to the boiler. A non-return valve allows fluid or gas to flow in only one direction, preventing backflow. In this case, it would prevent any fluid or gas from flowing back into the boiler when the stop valve is closed. Using a non-return valve closest to the boiler ensures that it is positioned in the most effective location to prevent backflow.

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72.
  1. An obstruction in the ___________ _______________ to the water column will cause a slow rising water level in the gauge glass after a gauge glass blow down.

Explanation

If there is an obstruction in the bottom connection to the water column, it will prevent the water from flowing freely. As a result, when a gauge glass blow down is performed, the water level in the gauge glass will rise slowly instead of quickly decreasing. This is because the obstruction hinders the water from being discharged efficiently, causing a delay in the water level adjustment in the gauge glass.

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73.
  1. An ___________________ Ring is on method used to support the Morrison Tube in a Scotch Marine Boiler.

Explanation

An Adamson Ring is a method used to support the Morrison Tube in a Scotch Marine Boiler. This means that the correct answer is "Adamson" as it is the specific type of ring used for this purpose.

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74.
  1. Today, most packaged watertube boilers follow one of the three designs. These are known as ___, ____, and ____ types.

Explanation

Today, most packaged watertube boilers follow one of the three designs, which are referred to as A, D, and O types.

Submit

75.
  1. The waste products from a sugar cane are used in a _______________ plant.

Explanation

Bagasse is the fibrous residue left after extracting juice from sugar cane. It is a byproduct of the sugar cane industry and is commonly used as a fuel in power plants. Therefore, the waste products from sugar cane, which include bagasse, are used in a power plant.

Submit

76.
  1. Anthracite coal is very hard, has a high percentage of _________ ________.

Explanation

Anthracite coal is known for its high percentage of fixed carbon. Fixed carbon refers to the carbon content in coal that remains after volatile matter and moisture have been removed. This high carbon content contributes to the coal's heating potential and makes it a valuable fuel source.

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77.
  1. A power boiler is a steam boiler that operates at pressures greater than ______ psi, or a hot water boiler that operates above _________ or _______°F.

Explanation

A power boiler is a type of boiler that operates at pressures greater than 15 psi, or a hot water boiler that operates above 160°F or 250°F.

Submit

78. The evaporator receives medium temperature __________ refrigerant.

Explanation

The evaporator receives medium temperature liquid refrigerant because the purpose of the evaporator is to absorb heat from the surrounding air or water, causing the refrigerant to evaporate and turn into a gas. This heat absorption process is more efficient when the refrigerant is in its liquid state.

Submit

79.
  1. A terminal reheat AHU delivers air at constant ______ degrees. A reheat coil is connected to the thermostat to maintain comfort in the space.

Explanation

A terminal reheat AHU delivers air at a constant temperature of 55 degrees. This is achieved by using a reheat coil connected to the thermostat, which allows for the adjustment of the air temperature to maintain comfort in the space.

Submit

80.
  1. The general classification of superheaters includes ___________ and _______________ types, depending on wheather they absorb radiant or convection heat.

Explanation

Superheaters are classified into radiant and convection types based on the type of heat they absorb. Radiant superheaters absorb heat through radiation, which is the transfer of heat through electromagnetic waves. Convection superheaters, on the other hand, absorb heat through convection, which is the transfer of heat through the movement of fluids or gases. Therefore, the correct answer is radiant and convection.

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81. Sulfur in the soot then unites with moisture from condensation to produce a _____________ ________, which is extremely corrosive to all steel construction contacted between the economizer and the stack

Explanation

Sulfur in the soot combines with moisture from condensation to form sulfurous acid. This acid is highly corrosive to all steel structures present between the economizer and the stack.

Submit

82.
  1. _______________ are added to the boiler to prevent steam line and condensate line corrosion. These chemicals are used because they will boil-off with the steam.

Explanation

Amines are added to the boiler to prevent steam line and condensate line corrosion. These chemicals are used because they will boil-off with the steam.

Submit

83.
  1. On HRT boilers, the shell is pitched 1 to 2 inches towards the back of the boiler to produce a more effective _________ ____________ of the boiler.

Explanation

The correct answer is "bottom blowdown." On HRT boilers, the shell is pitched 1 to 2 inches towards the back of the boiler to produce a more effective bottom blowdown of the boiler. This means that any sediment or impurities that settle at the bottom of the boiler can be easily drained and removed through the bottom blowdown process. This helps to maintain the efficiency and performance of the boiler by preventing the buildup of harmful deposits.

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84.
  1. Calcium and magnesium bicarbonate produce _____________ hardness.

Explanation

Calcium and magnesium bicarbonate produce temporary hardness. Temporary hardness refers to the presence of dissolved calcium and magnesium bicarbonate ions in water, which can cause scale buildup on surfaces and reduce the effectiveness of soaps and detergents. This type of hardness can be easily removed by boiling the water or using a water softener.

Submit

85.
  1. Operating a boiler at temperatures 10° to 20°F above the design temperature for long period of time can cause a life reduction of _____ to _____ years.

Explanation

Operating a boiler at temperatures 10°F to 20°F above the design temperature for a long period of time can cause a reduction in its lifespan by 10 to 20 years.

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86.
  1. There is no _____________ _________ ____ _________________ above the critical pressure, because water and steam have the same density.

Explanation

The statement in the question suggests that there is no change in density between water and steam above the critical pressure. This indicates that there is no phase change occurring, as the density of water and steam would be different if vaporization was taking place. The term "Latent Heat of vaporization" refers to the amount of heat energy required to convert a liquid into a vapor, and since there is no vaporization happening in this scenario, the latent heat of vaporization would not be applicable.

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87.
  1. The minimum size for the connection in between the gauge glass and the water column is _____.

Explanation

The minimum size for the connection between the gauge glass and the water column is 1/2". This means that the diameter of the connection should be half an inch. It is important to have a proper size for the connection to ensure that there is adequate flow of water between the gauge glass and the water column. Having a smaller size could restrict the flow, while a larger size may lead to leakage or improper readings. Therefore, 1/2" is the correct minimum size for the connection.

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88.
  1. The ____________ _________ mechanism on the high limit control call attention if the ________________ control has malfunctioned.

Explanation

The high limit control has two types of reset mechanisms: automatic reset and manual reset. In this case, the correct answer is "manual reset; operating." This means that if the operating control has malfunctioned, the manual reset mechanism on the high limit control will call attention to the issue.

Submit

89.
  1. To remove oil from the boiler, __________ _________ and __________ _______ are added to the boiler.

Explanation

Caustic soda and soda ash are added to the boiler to remove oil. Caustic soda is a strong alkaline compound that helps to break down the oil and emulsify it, making it easier to remove. Soda ash, also known as sodium carbonate, is a chemical compound that helps to neutralize acids and further aid in the removal of oil from the boiler. Together, these two substances work effectively to remove oil and maintain the cleanliness of the boiler.

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90.
  1. When a pump is used to circulate water though a heating system is a __________ ________________ system.

Explanation

When a pump is used to circulate water through a heating system, it creates forced convection. Forced convection refers to the movement of fluid (in this case, water) due to an external force (the pump). The pump forces the water to circulate through the heating system, allowing it to transfer heat and warm the space.

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91.
  1. Water at its boiling point is considered a _____________ liquid.

Explanation

Water at its boiling point is considered a saturated liquid because at this temperature, it is in equilibrium with its vapor phase. This means that the liquid and vapor phases coexist and the liquid is saturated with vapor molecules. Any additional heat added to the system will cause the liquid to transition into a vapor phase.

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92. What is the restriction in circulation due to a steam pocket inside the pump.

Explanation

The restriction in circulation due to a steam pocket inside the pump is known as "steam bound." Steam binding occurs when steam pockets form within the pump, leading to a decrease in the pump's efficiency and potential damage. The steam pockets hinder the normal flow of liquid, causing disruptions in circulation. This phenomenon is associated with issues such as cavitation, where the formation and collapse of vapor bubbles result in mechanical stress and damage to pump components. Proper pump design, operation, and maintenance practices are crucial to prevent steam binding and related problems. 

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93.
  1. Light domestic fuel oil is known as ________ ______ _____.

Explanation

Light domestic fuel oil is commonly referred to as #1 fuel oil. This type of fuel oil is lighter in viscosity and has a lower sulfur content compared to other fuel oils. It is commonly used for residential heating purposes and is also known as "kerosene" or "home heating oil".

Submit

94.
  1. A ____________ is a gelatin like substance that has very small particles in suspension. These particles are usually less than _______ microns in size.

Explanation

A colloidal is a gelatin-like substance that has very small particles in suspension. These particles are usually less than 0.20 microns in size.

Submit

95.
  1. A supercritical boiler is a boiler that operates in excess of ___________psia or ______°F.

Explanation

A supercritical boiler is a type of boiler that operates at pressures exceeding 3206.2 pounds per square inch absolute (psia) or temperatures exceeding 705.4 degrees Fahrenheit (°F). This means that the boiler is able to operate at higher pressures and temperatures, which allows for more efficient and effective heat transfer. By operating in the supercritical state, the boiler can achieve higher thermal efficiencies and generate more power.

Submit

96.
  1. The ratio of the boiler's heat output to its heat input is _____________ _____________.

Explanation

The correct answer is "boiler efficiency." Boiler efficiency refers to the ratio of the heat output from the boiler to the heat input into the boiler. It is a measure of how effectively the boiler converts fuel into useful heat energy. A higher boiler efficiency indicates that the boiler is able to extract more heat from the fuel, resulting in lower fuel consumption and reduced energy waste.

Submit

97.
  1. A High pressure steam boiler must have a ASME ______ stamp.

Explanation

A high pressure steam boiler must have an ASME "S" stamp. The ASME "S" stamp indicates that the boiler has been designed, constructed, and inspected in accordance with the ASME Boiler and Pressure Vessel Code Section I, which specifically covers power boilers. This stamp ensures that the boiler meets the necessary safety and quality standards for high pressure steam applications.

Submit

98.
  1. Hardness is a measure of the ____________ and _______________ ions in solution.

Explanation

Hardness is a measure of the concentration of calcium and magnesium ions in solution. These ions contribute to the overall hardness of water. Calcium and magnesium ions can come from various sources, such as dissolved minerals in the ground or rocks. The presence of these ions can affect the taste, appearance, and performance of water in various applications, such as in industrial processes or household use. Therefore, measuring the concentration of calcium and magnesium ions is important in determining the hardness of water.

Submit

99.
  1. Prior to entering a confined space, the minimum amount of oxygen in the space is _____ percent.

Explanation

The correct answer is 19. Prior to entering a confined space, it is important to ensure that there is a sufficient amount of oxygen present. The minimum amount of oxygen required for safe entry into a confined space is typically around 19 percent. Oxygen levels below this can be dangerous and may lead to asphyxiation or other health hazards. Therefore, it is crucial to monitor and confirm the oxygen levels before entering a confined space to ensure the safety of individuals.

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100.
  1. Rectifying phototube and lead sulfide phototube both prove flame in the boiler by sensing blank.

Explanation

Rectifying phototubes and lead sulfide phototubes are both types of photodetectors that can sense and detect light. In the context of the question, they are used to prove the presence of a flame in the boiler. Since flames emit visible light, these phototubes are able to detect and sense this visible light, indicating the presence of a flame. Therefore, the correct answer is visible light.

Submit

101.
  1. An ________ _________ mounted on the Water Column will sound an alarm if the water level is too high or too low.

Explanation

The correct answer is "alarm whistle." An alarm whistle mounted on the Water Column will sound an alarm if the water level is too high or too low. This type of whistle is designed to alert individuals nearby when there is an issue with the water level, ensuring prompt action can be taken to address the problem.

Submit

102.
  1. The color of Cylinder containing R410A is __________.

Explanation

Refrigerant cylinders, such as those containing R410A, follow a specific color-coding system to facilitate easy identification and to prevent mishandling. For R410A, a widely used refrigerant in air conditioning systems, the cylinder is colored rose. This standardization of colors helps technicians quickly recognize different types of refrigerants during installation or maintenance procedures. The rose color specifically helps in distinguishing R410A from other refrigerants which may have similar applications but different environmental impacts and handling requirements. Proper identification ensures safe usage, compliance with regulations, and efficient system performance.

Submit

103.
  1. All boiler heating surfaces are measured on the side blank the heat.

Explanation

The heating surfaces of a boiler are responsible for receiving heat. These surfaces are designed to absorb heat energy from the combustion process and transfer it to the water or steam in the boiler. Therefore, the correct answer is "receiving".

Submit

104.
  1. Boiler stop valves over 2" diameter must be ______________-___________- and -_________.

Explanation

Boiler stop valves over 2" diameter must have an outside screw and yolk. This configuration allows for easy operation and control of the valve. The outside screw refers to the screw mechanism that moves the valve stem in and out, while the yolk is the handle or wheel that is used to turn the screw. This design ensures that the valve can be easily opened and closed, providing efficient and reliable control over the flow of steam or water in the boiler system.

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105.
  1. To internally remove oxygen from the boiler, ____________ __________ is used.

Explanation

Sodium sulfite is used to internally remove oxygen from the boiler.

Submit

106.
  1. _____________prevents the tube end from being overheated and being burned off.

Explanation

Beading prevents the tube end from being overheated and being burned off. Beading is a process in which a raised ridge or bead is created on the edge of a tube or pipe. This ridge helps to secure the tube end and provides additional strength and stability, preventing it from overheating and being burned off. The bead acts as a barrier, protecting the tube end from excessive heat and potential damage.

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107.
  1. That ratio of the maximum fuel input rate and the minimum input rate is known as the _____________ ________.

Explanation

The turndown ratio refers to the ratio between the maximum and minimum input rates of fuel. It is a measure of the flexibility of a system or device to adjust its fuel input. A higher turndown ratio indicates a greater range of control and flexibility in adjusting the fuel input rate, while a lower turndown ratio means a more limited range of control. Therefore, the turndown ratio is the correct term to describe this ratio.

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108.
  1. Unlike an infrared scanner, the ultraviolet scanner is no affected by the light given off by hot _________________.

Explanation

An ultraviolet scanner is not affected by the light given off by hot refractories. Refractories are heat-resistant materials used in high-temperature industrial processes, such as furnaces. Infrared scanners rely on detecting the heat emitted by objects, including refractories, whereas ultraviolet scanners use ultraviolet light to detect and analyze different materials. Therefore, the ultraviolet scanner is not affected by the light emitted by hot refractories.

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109.
  1. A 26" x 48" x rectangular Duct is replaced with a round Duct. What is the minimum diameter of the round Duct to provide the same area?

Explanation



To match the airflow area of a rectangular duct (26" x 48"), a round duct's area must be equal. Using the area of the rectangle, we calculate the diameter of a circle that would have the same area. The formula involves dividing the rectangular area by π and taking the square root, then doubling it for the diameter, resulting in approximately 39.87 inches.
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110.
  1. A refrigerant system using R-134a is running at 148 psi on the discharge and 16psi on the suction. What is the compression ratio of the compression?

Explanation

The compression ratio (CR) of a refrigeration or compression system is calculated by dividing the absolute discharge pressure (P2) by the absolute suction pressure (P1):



CR = P2 / P1



In this case, you provided the pressures in psi, but to calculate the compression ratio, we need to convert them to absolute pressures in psi (psia). Absolute pressure is the sum of the gauge pressure and atmospheric pressure (14.7 psi at sea level).



Absolute discharge pressure (P2) = 148 psi + 14.7 psi = 162.7 psi

Absolute suction pressure (P1) = 16 psi + 14.7 psi = 30.7 psi



Now, we can calculate the compression ratio:



CR = P2 / P1

CR = 162.7 psi / 30.7 psi



CR ≈ 5.3



So, the compression ratio of the refrigerant system is approximately 5.3:1.

Submit

111.
  1. _______ _______________ make the final heat recovery from the boiler flue gases with which they preheat the incoming furnace air for its combustion with fuel.

Explanation

An air preheater is used to make the final heat recovery from the boiler flue gases and preheat the incoming furnace air for combustion with fuel. This device helps to increase the efficiency of the combustion process by utilizing the waste heat from the flue gases to heat up the incoming air. By preheating the air, less fuel is required to achieve the desired temperature, resulting in energy savings and reduced emissions.

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112.
  1. _____________ consist of relative close-spaced vertical tubes forming the four walls of the furnace.

Explanation

Waterwalls consist of relatively close-spaced vertical tubes forming the four walls of the furnace. These tubes are designed to absorb heat from the combustion process and transfer it to the surrounding water, creating steam. Waterwalls are an important component in boilers and furnaces as they help in the efficient transfer of heat and ensure the proper functioning of the system.

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113.
  1. A three element feedwater regulator senses _________________ _________, ____________ _________, and _____________ ___________.

Explanation

The three elements that a feedwater regulator senses are feedwater flow, steam flow, and water level. These are important parameters to monitor in order to ensure the proper functioning and control of the feedwater system. By measuring the feedwater flow, the regulator can adjust the flow rate to match the steam demand. Monitoring the steam flow allows for proper control of the steam supply, while monitoring the water level helps prevent overfilling or underfilling of the system.

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114.
  1. The last form of over-pressure protection on the boiler, prior to lifting the safety valve is the _________ ___________ ___________.

Explanation

The high limit control is the last form of over-pressure protection on the boiler before the safety valve is activated. This control is set to a specific pressure limit, and if the pressure exceeds this limit, it will automatically shut down the boiler to prevent any potential damage or hazards. It acts as a safeguard to ensure that the pressure within the boiler does not reach dangerous levels.

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115.
  1. The color of Cylinder containing R-123 is _________ ________  before 2020.

Explanation

The color of the cylinder containing R-123 is light gray before 2020.

Submit

116. The color of Cylinder containing R -134a is _________ ________ before 2020. 

Explanation

The color of the cylinder containing R-134a is light blue before 2020.

Submit

117.
  1. The ratio of the maximum fuel input rate and the minimum fuel input rate is known as the blank.

Explanation

The turn down ratio refers to the ratio between the maximum and minimum fuel input rates. This ratio is used to measure the flexibility of a fuel system, as it determines the range of fuel flow that can be achieved. A higher turn down ratio indicates a greater range of fuel flow, allowing for more precise control of the combustion process. Therefore, the turn down ratio is the correct term for the given description.

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118. Bent tubes are more __________ than straight tubes.

Explanation

Bent tubes are more flexible than straight tubes because they can easily bend and conform to different shapes and angles. This flexibility allows them to be used in various applications where straight tubes would not be able to fit or adapt. Additionally, the ability to bend and flex makes bent tubes more resistant to breakage or damage caused by external forces or vibrations. Therefore, bent tubes offer better flexibility and versatility compared to straight tubes.

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119.
  1. Flow of liquid in ad coil-type boiler is _______________ through the coils spiral-wound in a counterflow direction to the combustion gases.

Explanation

The flow of liquid in a coil-type boiler is downward through the coils spiral-wound in a counterflow direction to the combustion gases. This means that the liquid enters the top of the coil and flows downward towards the bottom, while the combustion gases flow in the opposite direction. This counterflow arrangement allows for efficient heat transfer between the liquid and the combustion gases, maximizing the boiler's effectiveness.

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120.
  1. A centrifugal pump uses a ________ to convert velocity energy to pressure energy.

Explanation

A centrifugal pump uses a volute to convert velocity energy to pressure energy. The volute is a curved casing that surrounds the impeller, which is the rotating component of the pump. As the impeller spins, it creates a centrifugal force that pushes the fluid towards the outer edges of the volute. This causes the fluid to gain pressure energy as its velocity decreases. The volute then directs the high-pressure fluid towards the pump outlet, allowing it to be used for various applications such as water circulation, irrigation, or industrial processes.

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121.
  1. The deaerator is an open feedwater heater that is used to remove ___________ from the boiler feedwater.

Explanation

The deaerator is an open feedwater heater that is used to remove oxygen from the boiler feedwater. Oxygen in the feedwater can cause corrosion and damage to the boiler system. The deaerator works by heating the feedwater and exposing it to steam, which helps to remove dissolved gases, including oxygen. This helps to protect the boiler system and improve its efficiency.

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122.
  1. A boiler horsepower is the evaporation into dry saturated steam of ________ pounds per hour from and 212°F.

Explanation

A boiler horsepower is a unit of measurement used to indicate the rate at which a boiler can produce steam. In this context, it refers to the evaporation of steam into dry saturated steam. The answer of 34.5 pounds per hour indicates that a boiler with one horsepower can produce 34.5 pounds of dry saturated steam per hour when the water temperature is at 212°F.

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123.
  1. A low pressure steam boiler must have a ASME ____ stamp.

Explanation

A low pressure steam boiler must have an ASME H stamp. This indicates that the boiler is designed and constructed in accordance with the ASME Boiler and Pressure Vessel Code Section IV, which specifically covers low pressure steam heating boilers. The H stamp ensures that the boiler meets the necessary safety standards and regulations for its intended use.

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124.
  1. A method for testing the material for soundness without affecting the material physically or chemically is known as ____________________ __________.

Explanation

Non-destructive testing refers to a method of evaluating the quality and integrity of a material without causing any physical or chemical changes to it. This technique allows for the examination of the material's soundness without causing any damage or alteration. It is commonly used to detect defects, flaws, or abnormalities in various materials, such as metals, composites, and concrete, without compromising their structural integrity. Visual inspection, indirect sampling, and accumulation testing do not accurately describe the process of testing the material without affecting it physically or chemically.

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125.
  1. ___________ ___________ is a device installed on the suction of a pump to ensure that the suction piping stays full of water.

Explanation

A foot valve is a device installed on the suction of a pump to ensure that the suction piping stays full of water. It is designed with a one-way valve that allows water to flow into the pump but prevents it from flowing back out. This helps maintain the prime of the pump, ensuring that it can effectively draw water from the source without any interruptions or air pockets in the suction line.

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126.
  1. ______________ usually caused cavities to form at grain boundaries in metal, and these cavities coalesce to form cracks.

Explanation

Creep is the correct answer because it refers to the slow and gradual deformation of a material under constant stress or high temperatures. This can cause cavities to form at the grain boundaries in metal, which then coalesce to form cracks.

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127.
  1. The color of Cylinder containing R-12 is _________ before 2020.

Explanation

The color of the cylinder containing R-12 is white before 2020.

Submit

128.
  1. A turbine pump uses a __________ __________ to convert velocity to pressure energy.

Explanation

A turbine pump uses guide vanes to convert velocity to pressure energy. Guide vanes are stationary vanes that direct the flow of fluid into the impeller, which then converts the velocity of the fluid into pressure energy. The guide vanes help to control and direct the flow of fluid, ensuring efficient conversion of velocity to pressure.

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129.
  1. The presence of free oxygen in the boiler water will produce ____________ attack on the boiler metal surfaces.

Explanation

The presence of free oxygen in the boiler water can lead to pitting attack on the boiler metal surfaces. Pitting corrosion occurs when localized areas on the metal surface become corroded, forming small pits or holes. This type of corrosion is often more severe and can cause rapid deterioration of the metal compared to general corrosion. The presence of free oxygen provides an environment conducive to the formation of corrosion cells, leading to pitting corrosion.

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130.
  1. The temperature of a liquid minus 32 is the ____________ of the liquid.

Explanation

Enthalpy is a thermodynamic property that represents the total heat content of a system. In this context, the temperature of a liquid minus 32 refers to a change in temperature or a difference in heat content. Therefore, enthalpy is the appropriate term to describe this concept.

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131.
  1. The National Board of Boiler and Pressure Vessel Repair requires an ____ stamp for companies that repair boilers.

Explanation

The correct answer is "R." The National Board of Boiler and Pressure Vessel Repair requires an "R" stamp for companies that repair boilers. This stamp signifies that the company has met the necessary qualifications and standards set by the National Board. It ensures that the repairs are done by qualified personnel and that the boilers are safe to use.

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132.
  1. ASME code requires all boiler safety valves be stamped with a _____ stamp.

Explanation

The correct answer is V. According to the ASME code, all boiler safety valves must be stamped with a V stamp. This stamp indicates that the safety valve has been tested and meets the requirements set by the ASME code for pressure relief devices. The V stamp ensures that the safety valve is reliable and will properly relieve excess pressure in the boiler to prevent any potential accidents or damage.

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133.
  1. The "Three T's for proper fuel combustion are ___________, ________________, and _________________.

Explanation

The three T's for proper fuel combustion are time, temperature, and turbulence. Time refers to the duration of the combustion process, allowing for complete and efficient burning of the fuel. Temperature is necessary to initiate and sustain the combustion reaction. Turbulence is important for mixing the fuel and air, ensuring proper fuel-air ratio and enhancing the combustion process.

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134.
  1. Name the 4 steps needed to perform regeneration on a zeolite water softer _____________, ________________, ________________________, _____________________________.

Explanation

The correct answer is "Backwash, Brine Rinse, slow / fast rinse, back in service." These are the four steps needed to perform regeneration on a zeolite water softener. First, the system needs to be backwashed to remove any accumulated debris or contaminants. Then, a brine rinse is done to flush out the accumulated hardness minerals from the zeolite resin bed. After that, a slow or fast rinse is performed to ensure that all the brine solution is removed from the system. Finally, the system is put back in service, ready to soften water again.

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135.
  1. __________ ________ boilers recover the heat in the exhaust from a gas turbine to produce useful steam.

Explanation

Waste heat boilers recover the heat in the exhaust from a gas turbine to produce useful steam. This means that they utilize the excess heat generated as a byproduct of a process or system, such as a gas turbine, to generate steam, which can then be used for various purposes. Waste heat boilers are an efficient way to harness and utilize the otherwise wasted heat energy, making them an important component in cogeneration plants.

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136.
  1. Number 4 fuel oil has _____________btu's per pound.

Explanation

Number 4 fuel oil has 18,840 btu's per pound.

Submit

137.
  1. If a bulge in a boiler is not down more than ______ of its length, it should be left alone unless the metal is too badly burned.

Explanation

If a bulge in a boiler is not down more than 2% of its length, it should be left alone unless the metal is too badly burned. This means that if the bulge is less than 2% of the length of the boiler, it is considered acceptable and does not require any immediate action. However, if the metal is severely damaged or burned, it may need to be addressed regardless of the size of the bulge.

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138.
  1. There are _________ BTU's per gallon and _______________ BTU's per pound of #4 fuel oil.

Explanation

#4 fuel oil has 146,000 BTUs per gallon and 18,840 BTUs per pound.

Submit

139.
  1. Natural gas has a heating value of ______ BTU's per ft³, or ____________ BTU's per therm.

Explanation

Natural gas has a heating value of 1,000 BTU's per ft³, or 100,000 BTU's per therm.

Submit

140.
  1. A water column is used to minimize water level ___________________in the gauge glass.

Explanation

A water column is used to minimize water level fluctuation in the gauge glass. This means that the water column helps to stabilize the water level in the gauge glass, preventing it from rapidly changing or fluctuating.

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141.
  1. Two or more safety valves are required on a boiler with a heating surface in excess of _________ square feet, or electric input of _________KW.

Explanation

If a boiler has a heating surface in excess of 500 square feet or an electric input of 500 KW, it is required to have two or more safety valves. This is because a larger heating surface or electric input can generate more heat and pressure, increasing the risk of a potential explosion or other safety hazards. By having multiple safety valves, it ensures that there are redundant safety measures in place to relieve excess pressure and maintain the safe operation of the boiler.

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142.
  1. __________________ coal burns with a yellow, smoky flame.

Explanation

Bituminous coal burns with a yellow, smoky flame.

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143.
  1. Galvanic corrosion occurs when ______________, metals are in direct contact with each other in a _______________ environment.

Explanation

Galvanic corrosion occurs when dissimilar metals are in direct contact with each other in a conductive environment. This is because when two different metals come into contact, an electrochemical reaction takes place due to the difference in their electrical potentials. The conductive environment facilitates the flow of electrons between the metals, leading to the corrosion of the less noble metal. The presence of moisture or humidity further accelerates this corrosion process.

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144.
  1. In order for a black liquor boiler to sustain combustion, the liquor must contain over _____ % of solids.

Explanation

A black liquor boiler requires a high concentration of solids in the liquor in order to sustain combustion. The correct answer is 58% because this is the percentage of solids that is necessary for the boiler to function properly.

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145.
  1. The two methods for deteminating the grindability of coal are ________-_______ , and _______________ test.

Explanation

The two methods for determining the grindability of coal are ball-mill and Hardgrove test. The ball-mill test involves grinding a sample of coal in a ball mill to measure the pulverizing characteristics, while the Hardgrove test measures the relative ease of pulverization of coal using a standard Hardgrove grindability index (HGI) machine. These tests are commonly used in the coal industry to assess the grindability or the ease of grinding coal, which is important in determining its suitability for various industrial processes.

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146.
  1. Leaking safety valve should be ____________ to stop the leakage, never ___________.by adjustment to stop the leakage.

Explanation

When a safety valve is leaking, it means that it is not sealing properly. To fix this issue, the valve should be reground, which involves smoothing the surface of the valve and its seat to ensure a proper seal. Additionally, the valve should be tightened to ensure that it is securely closed and no leakage occurs. Patching or replacing the valve would not address the underlying issue of improper sealing.

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147.
  1. Leaking that occurs inside a centrifugal pump from the discharge to the suction, is known as _______.

Explanation

Slip refers to the leaking that occurs inside a centrifugal pump from the discharge to the suction. It is a common issue in centrifugal pumps where a small amount of fluid leaks back from the high-pressure side to the low-pressure side. This can happen due to various reasons such as worn-out seals, damaged impeller, or excessive pressure. Slip can affect the efficiency and performance of the pump, and it needs to be addressed to prevent any further damage or loss of fluid.

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148.
  1. The color of Cylinder containing R-11 is _________ before 2020.

Explanation

The color of the cylinder containing R-11 is orange before 2020.

Submit

149.
  1. A disavantage of a HRT boiler is that scale or mud deposits on the bottom of the shell, it will rapidly blank and produce blank or blank.

Explanation

A disadvantage of a HRT (Horizontal Return Tubular) boiler is that if scale or mud deposits accumulate on the bottom of the shell, it will rapidly overheat, causing the tubes to bulge and the boiler to fail. The term "bags" is not applicable in this context and "blister" refers to a different type of failure.

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150.
  1. The __________ __________ ________ takes air from the atmosphere, and delivers it through air ducts to air preheaters and burners.

Explanation

A forced draft fan is a device that takes air from the atmosphere and delivers it through air ducts to air preheaters and burners. This fan is responsible for creating a positive pressure in the combustion chamber, forcing the air into the system. It helps in maintaining proper combustion by supplying the required amount of air to the burners.

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151.
  1. For a company to a make qualified repairs to a safety valve they must have a ______ stamp

Explanation

In order for a company to make qualified repairs to a safety valve, they must have a VR stamp.

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152.
  1. The _________ __________ and _____________ _________ _______ sense heat to prove flame in the boiler.

Explanation

The stack switch and rectifying flame rod are used to sense heat and prove flame in the boiler. The stack switch is a device that detects the temperature in the flue gas stack, while the rectifying flame rod is a sensor that detects the presence of a flame by measuring the electrical current generated by the flame. Together, these two components provide a reliable method for monitoring and ensuring the presence of a flame in the boiler.

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153.
  1. The color of Cylinder containing R-401A is __________.

Explanation



The cylinder containing R-401A refrigerant is colored pinkish red. The pinkish red color is used to identify R-401A, which is a type of hydrofluorocarbon (HFC) refrigerant. This color-coding system is important in the refrigeration industry as it helps technicians, engineers, and other professionals to quickly and accurately identify the refrigerant being used.
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154.
  1. The temperature at which fuel oil will give off a vapor that will burn continuously once it has been ignited id the __________ __________.

Explanation

The fire point is the temperature at which fuel oil will continue to burn once it has been ignited. It is a higher temperature than the flash point, which is the temperature at which fuel oil will produce enough vapor to ignite but may not sustain a continuous flame. The fire point is an important safety consideration as it indicates the temperature at which a fire can spread and cause significant damage.

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155.
  1. ______________ acid is used to dissolve scale deposits during an acid cleaning.

Explanation

Hydrochloric acid is commonly used to dissolve scale deposits during an acid cleaning process. It is a strong acid that can effectively break down and remove mineral deposits such as calcium carbonate and limescale. Hydrochloric acid is preferred for this purpose due to its high reactivity and ability to dissolve various types of scales. Additionally, it is readily available and cost-effective, making it a popular choice for acid cleaning applications.

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156.
  1. _______________ is the transfer of heat from a liquid flowing over the surface of a body.

Explanation

Convection is the transfer of heat from a liquid flowing over the surface of a body. This process occurs when the heated liquid comes into contact with the surface, absorbs the heat, and then carries it away as it flows. The movement of the liquid helps to distribute the heat evenly and efficiently.

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157.
  1. The maximum voltage allowable on a control circuit is ______ volts.

Explanation

The maximum voltage allowable on a control circuit is 150 volts. This means that any voltage above 150 volts can potentially damage or malfunction the control circuit. It is important to adhere to this maximum voltage limit to ensure the proper functioning and longevity of the control circuit.

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158.
  1. The maximum adjustment to the setpoint of safety valve is ______ percent.

Explanation

The maximum adjustment to the setpoint of a safety valve is 10 percent. This means that the setpoint of the safety valve can be increased or decreased by a maximum of 10 percent from its original value. Adjusting the setpoint allows for fine-tuning the safety valve to ensure that it opens at the desired pressure to protect the system from overpressure.

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159.
  1. If a tubesheet is corroded more than ______ percent of the original thickness, the defective section must be cutout and flush patched installed.

Explanation

If a tubesheet is corroded more than 50 percent of the original thickness, the defective section must be cutout and flush patched installed. This means that if the corrosion has caused more than half of the tubesheet's original thickness to be eroded, it is necessary to remove that section and replace it with a flush patch. This is likely because the corrosion has weakened the tubesheet significantly and it cannot function effectively in its current state.

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160.
  1. City Water pressure entering a building is 120 psi. The building is 185 feet tall, there is _____psi city water pressure on the top floor of the building.

Explanation

The pressure of water decreases with increasing height due to the gravitational force acting on it. This decrease in pressure is approximately 0.433 psi per foot of height. Therefore, for a building that is 185 feet tall, the decrease in pressure would be 185 multiplied by 0.433 psi. Calculating this, we get approximately 80 psi. So, the city water pressure on the top floor of the building would be 120 psi minus 80 psi, which equals 40 psi.

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161.
  1. The number of tubes in each of the four passes is ____________ to maintain constant ______________ and ________ _______________.

Explanation

In order to maintain constant heat transfer, it is necessary to reduce the velocity of the fluid. This is because reducing the velocity allows for more time for heat exchange to occur between the fluid and the tubes. By reducing the velocity, the fluid can spend more time in contact with the tubes, increasing the efficiency of heat transfer. Therefore, reducing the velocity is necessary to maintain constant heat transfer.

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162.
  1. The early watertube boilers followed some fire tube designs,being straight tubes suspended over a furnace with the tubes rolled in two types of headers (1)____________or (2) ______________ ______________.

Explanation

The early watertube boilers had straight tubes that were suspended over a furnace. These tubes were rolled into two types of headers: box headers and sinuous headers.

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163.
  1. The chief heat producing elements in fuels are _______, _________, and _____________.

Explanation

The chief heat producing elements in fuels are carbon, hydrogen, and sulfur. These elements have high energy content and when they undergo combustion, they release a significant amount of heat energy. Carbon and hydrogen are present in most organic compounds, which are commonly found in fuels such as coal, oil, and natural gas. Sulfur is also present in some fuels, and its combustion contributes to the heat production. Therefore, carbon, hydrogen, and sulfur are the primary elements responsible for the heat generation in fuels.

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164.
  1. Testing coal for moisture, percent volatile matter, fixed carbon, and ash content is a _____________ _____________.

Explanation

Proximate analysis is a method used to determine the composition of coal by testing its moisture, volatile matter, fixed carbon, and ash content. This analysis provides important information about the quality and potential uses of the coal. It helps in understanding its heating value, combustion characteristics, and suitability for different applications. Therefore, the correct answer for this question is proximate analysis.

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165.
  1. A temperature sensor that measures the resistance of a platinum wire at different temperatures is a _______________ _____________________ ____________________.

Explanation

A temperature sensor that measures the resistance of a platinum wire at different temperatures is called a Resistance Temperature Sensor. This type of sensor relies on the principle that the resistance of a metal, such as platinum, changes with temperature. By measuring the resistance of the wire, the sensor can accurately determine the temperature.

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166.
  1. A 3" pressure-reducing valve has a ¾ inch bypass line. The inlet pressure is 100 psi and the outlet pressure is 5 psi. Given the orifice capacity (OC) is 5,929 pounds per hour (PPH), the valve size pressure adjustment (VSPA) is 7.39, and the bypass pressure adjustment (BPA) is 0.53, what should the safety valve on the discharge be rated for?

Explanation

The correct answer is 23,222 pounds per hour, which is derived by multiplying the orifice capacity (OC) of 5,929 PPH by the valve size pressure adjustment (VSPA) of 7.39 and the bypass pressure adjustment (BPA) of 0.53. This calculation adjusts the orifice capacity for the specific valve size and bypass configuration, determining the safety valve's required rating for optimal performance and safety.

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167.
  1. The picture above is an example of a ______________ type safety valve

Explanation

The picture above is an example of a nozzle type safety valve. A nozzle safety valve is a type of pressure relief valve that is used to control and release excess pressure in a system. It consists of a nozzle-shaped outlet that allows the pressure to be released in a controlled manner. This type of safety valve is commonly used in steam systems and other high-pressure applications.

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168.
  1. ______________ is used on high pressure steam plants to absorb oxygen. It's is not typically used on low pressure steam plants because it is a slow reaction to absorb oxygen.

Explanation

Hydrazine is used on high pressure steam plants to absorb oxygen. It is not typically used on low pressure steam plants because it is a slow reaction to absorb oxygen.

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169.
  1. A ___________ Pump is a Positive Displacement Pump.

Explanation



A reciprocating pump is a type of positive displacement pump where the high-pressure seal reciprocates with the piston. These pumps are capable of moving fluid at a consistent rate regardless of the system pressure, which makes them ideal for applications requiring precise volumes of fluid to be moved. Reciprocating pumps are commonly used in scenarios where a specific amount of fluid must be dealt with in a controlled, steady manner.
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170.
  1. The __________ ______________ burner can burn almost any fuel oil, at almost any temperature.

Explanation

Steam atomizing burners are designed to burn fuel oil by using steam to atomize or break up the oil into small droplets. This allows for efficient combustion of the fuel oil at various temperatures. Unlike fuel atomizing burners, which rely solely on the pressure of the fuel oil to atomize it, steam atomizing burners can handle a wider range of fuel oils and provide better control over the combustion process. Therefore, the given answer is the most appropriate choice for a burner that can burn almost any fuel oil, at almost any temperature.

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171.
  1. Large amounts of _________________ in the exhaust flue gas can result in a blade erosion in the induced draft fan.

Explanation

Large amounts of particulates in the exhaust flue gas can result in blade erosion in the induced draft fan. This is because particulates, which are solid or liquid particles suspended in the gas, can cause abrasion and wear on the fan blades. As the flue gas containing high levels of particulates passes through the fan, these particles can impact and erode the blades over time. This erosion can lead to reduced efficiency and performance of the fan, potentially requiring maintenance or replacement.

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172.
  1. When water is entrained in the steam it is called ___________ due to high steam flow rates.

Explanation

Priming is the correct answer because when water is entrained in the steam due to high steam flow rates, it is referred to as priming. Priming occurs when water droplets are carried along with the steam and can cause damage to equipment and decrease system efficiency.

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173.
  1. The safety valve capacity must be sufficient to relieve all the steam that the boiler can generate at the _______________ _____________ __________ without allowing the pressure to rise more than _____ percent above the maximum allowable working pressure.

Explanation

The safety valve capacity must be sufficient to relieve all the steam that the boiler can generate at the maximum firing rate without allowing the pressure to rise more than 6 percent above the maximum allowable working pressure. This ensures that the safety valve can handle the maximum amount of steam being produced by the boiler and prevent the pressure from exceeding the safe limit by more than 6 percent.

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174.
  1. The percentage of excess air required to burn coal is about    percent.

Explanation

The percentage of excess air required to burn coal is about 50 percent. Excess air is the amount of air supplied to a combustion process that exceeds the theoretical requirement for complete combustion. In the case of burning coal, a certain amount of excess air is necessary to ensure complete combustion and prevent the formation of harmful byproducts such as carbon monoxide. A value of 50 percent indicates that half of the air supplied is in excess of what is needed for complete combustion.

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175.
  1. An induction AHU used High Pressure air flowing through the ________ to draw air across the heating coil.

Explanation

An induction AHU (Air Handling Unit) uses high pressure air flowing through the induction nozzles to create a low pressure zone, which in turn draws air across the heating coil. The induction nozzles create a venturi effect, where the high velocity air passing through the nozzles creates a low pressure zone that draws in surrounding air. This allows the AHU to efficiently heat or cool the air passing through the heating coil.

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176.
  1. For proper combustion air into the boiler room, one square inch of outdoor air opening is required per ________BTU/hr input.

Explanation

For proper combustion air into the boiler room, one square inch of outdoor air opening is required per 4,000 BTU/hr input. This means that for every 4,000 BTU/hr of input, there should be one square inch of outdoor air opening to ensure adequate air supply for combustion.

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177.
  1. Infrared flame scanners use a _______ __________ cell to detect the presence of the flame

Explanation

Infrared flame scanners use a lead sulfide cell to detect the presence of the flame. Lead sulfide is a material that has the property of being sensitive to infrared radiation. When a flame is present, it emits infrared radiation, which is detected by the lead sulfide cell. This detection allows the flame scanner to trigger appropriate actions, such as shutting off a fuel supply or activating a fire suppression system.

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178.
  1. The pressure relief valve on a hot water boiler must be at least ______ diameter and not more than ______diameter.

Explanation

The pressure relief valve on a hot water boiler must be at least 3/4" in diameter to ensure proper functioning and prevent excessive pressure buildup. It should also not exceed 4 1/2" in diameter to avoid any potential issues or restrictions in the system.

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179.
  1. Coal gas is produced using the volatile matter from _______________ coal, an d has a heating value of __________ BTU's per cubic foot.

Explanation

Coal gas is produced using the volatile matter from bituminous coal, and has a heating value of 550 BTU's per cubic foot.

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180. Butane and propane are produced from the manufacturing of _____________. Propane has a heating value of __________BTU's per cubic foot. Butane has a heating value of about

Explanation

Butane and propane are produced from the manufacturing of gasoline. Propane has a heating value of 2500 BTU's per cubic foot, while butane has a heating value of about 3200 BTU's.

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181.
  1. A 600 horsepower boiler's operating at 15 psi the boiler burners 18,255 ft³ per hour of natural gas containing 1025 BTU's per ft³. The Chimney receives 8,750 pph of flue gas containing 475 BTU's per pound. What is the boiler efficiency through the indirect method?

Explanation

To calculate boiler efficiency indirectly:

Input: Calculate heat input from natural gas.

Output: Determine heat absorbed by water using boiler horsepower.

Losses: Calculate heat lost in flue gas.

Efficiency: Use formula Efficiency = (1 - Losses/Input) × 100.

Given values yield an efficiency of 77.8%.

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182.
  1. A pressure gauge installed 30 feet below the boiler drum reads 135 psi. The actual pressure on the boiler is ________ psi.

Explanation

The pressure gauge installed 30 feet below the boiler drum reads 135 psi. However, the actual pressure on the boiler would be slightly lower due to the hydrostatic pressure caused by the weight of the water column above the gauge. The hydrostatic pressure increases by 0.433 psi for every foot of water depth. Since the gauge is 30 feet below the drum, the hydrostatic pressure would be 13 psi (30 feet x 0.433 psi/ft). Therefore, the actual pressure on the boiler would be 135 psi - 13 psi = 122 psi.

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183.
  1. The Economic boiler was an improvement on the HRT boiler. The economic boiler has more ___________ ____________ per square foot of floor space, it requires less __________ _________, and is easier to _____________.as a single package unit.

Explanation

The economic boiler has more heating surface per square foot of floor space, which means it can produce more steam. It also requires less brick work, making it easier to install and maintain.

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184.
  1. A reciprocating pump has a water cylinder that is 18" diameter and 15" long, the plunger in the cylinder stroke ¾ of the length of the cylinder. What is the volume of water displaced with each stroke of the plunger?

Explanation

The volume of water displaced with each stroke of the plunger can be calculated using the formula for the volume of a cylinder, which is V = πr²h. In this case, the diameter of the cylinder is given as 18", so the radius is half of that, which is 9". The length of the cylinder is given as 15". The plunger stroke is given as ¾ of the length of the cylinder, which is 15" x ¾ = 11.25". Using these values, we can calculate the volume as V = π(9²)(11.25) = 2,861.325 cu".

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185.
  1. A ________ __________ is constructed of flat plates, referred to as a tube sheet an tube cap sheet.

Explanation

A box header is a type of heat exchanger that is constructed of flat plates, specifically a tube sheet and tube cap sheet. This type of heat exchanger is commonly used in industrial applications to transfer heat between fluids. The box header design allows for efficient heat transfer due to the large surface area provided by the flat plates.

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186.
  1. The percentage of excess air required to burn natural gas, fuel oil, or pulverize coal is    to    percent.

Explanation

The correct answer is 10-30. This range represents the percentage of excess air required to burn natural gas, fuel oil, or pulverized coal. Excess air is the amount of air supplied to the combustion process above the theoretical amount required for complete combustion. A range of 10-30% ensures efficient and complete combustion while minimizing emissions.

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187.
  1. Temporary hard water is water that contains large quantities of calcium and magnesium_______________.

Explanation

Temporary hard water is water that contains large quantities of calcium and magnesium bicarbonate. When temporary hard water is heated or boiled, the bicarbonate ions decompose, resulting in the formation of insoluble carbonates. This causes the formation of scale or deposits on surfaces, such as in kettles or pipes.

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188.
  1. Permanently hard water is water that contains large quantities of calcium and magnesium blank.

Explanation

Permanently hard water is water that contains large quantities of calcium and magnesium sulfites. Sulfites are compounds that can contribute to water hardness and can form insoluble precipitates with calcium and magnesium ions. These precipitates can cause scale buildup in pipes and appliances, reducing their efficiency and lifespan.

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189. Match the following

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190. Match the following

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In order to permit the water in a hot water heating system to expand...
The _______________ is the heart of the refrigeration system.
In _______________ boilers, the water passes through the tubes, and...
A solid that precipitates out of solution and adhere to the boiler...
The presence of scale on the boiler tubes will result in a...
A ________ _______ AHU supplies conditioned air to only one area of...
____________is the bleeding of a portion of the water to remove...
______________ is the deterioration of the boiler metal by a chemical...
______ ________________ are used extensively in...
When two or more boilers are connected into a common steam header, and...
A 10 x 5x 15 duplex reciprocating pump has a steam cylinder diameter...
Sulfur in the soot then unites with moisture from condensation to...
A _______________ ____________ air handler unit operates at the rated...
___________ deflect the hot gases back and forth between the tubes a...
A British thermal unit, BTU, is the amount of heat that need to raise...
The low water fuel cut-off will shut off the fuel to the burner before...
The _____________ on the refrigeration system absorbs the heat from...
A _________ _______AHU has heating and cooling coils located at the...
The hot gases from the furnace pass into a blank lined combustion...
Cogeneration plants sell ____________ to the local industrial plants,...
A dry pipe on a Scotch Marine Boiler is used to remove _____________...
The color of Cylinder containing R -22 is ___________ ________ before...
The lowest visible water level in the gauge glass is ___ above the top...
The presence of elevated levels of ______ in the fuel gas is an...
______________ BTU's per hour output is one boiler horsepower.
A _______________ is a U-tube draft gauge to measure the differential...
When using a lift lever to manually test a safety valve, the boiler...
_______ drum below the rear headers was used to collect sediment and...
_______________ is when water or impurities leave the boiler with the...
In conduction the transfer of heat from one material to another occurs...
When the boiler steam pressure reaches setpoint of the main scale of...
The modulating control controls the ___________ ________ of the...
The _____________ on the refrigeration system rejects the heat from...
Welding a flat strip of metal between the waterwall tubes is known as...
The three classes of feedwater pumps are _______________,...
Welding a flat strip of metal between the waterwall tubes is known as...
The minimum size of the piping between the boiler and the water column...
Fire tube boilers are likely to leak due to cracking, burning and...
The test most commonly used for determining wall thickness of pipes or...
_____ ______ are a potential source of oil contamination of...
The two types of electric boilers are _______________ and...
A device used to reduce the temperature of superheated steam to a...
A solution is said to be ______________ when it can no longer dissolve...
The flow of heat through electromagnetic waves is known as...
The accumulation of carbon dioxide in the condensate system produces...
Because the shell of the HRT is exposed to the fire, it requires a...
The _______________ _______________ _________ is used to control the...
The number 4,5 and 6 oils are heavy and viscous, thus require...
_____________ is the replacement for refrigerant R-22.
A slow opening blowdown valve must complete _____ turns between full...
__________ _________ is the temperature at which fuel oil will give...
In an open feedwater heater, steam and water are in __________...
In a ___________ water softener, calcium and magnesium ions are...
A through stay differs from a diagonal stay in that it runs the...
The operation of a black liquor boiler is known for its ________...
One grain is equal to ________ parts per million.
When the boiler water has a high level of solids, steam bubbles can be...
Water hammer is caused by quickly opening a __________ _________. The...
When a furnace baffle breaks, the gases short-circuit one or more...
A ____________________ pump can be started with the discharge valve...
A dual Duct AHU has hot and cold Ducts connected to ___________...
Scale accumulation on the waterside of a firetube boiler can lead to...
A stay that is shorter than 8" and threaded is required to have a...
The pipes connecting the water column to the boiler must be a minimum...
The operation of a black liquor boiler is known for its __________...
A cylindrical cup rotating at high speeds is utilized in a _________...
One grain is equal to ______ parts per million. _________grains equals...
Too much _______ causes dense, white smoke.
Comparing the mill test report with the markings on the material is a...
According to ASME code a HTHW boiler is any boiler that operates above...
In lieu of a stop valve a ____________ _____may be used instead of the...
An obstruction in the ___________ _______________ to the water column...
An ___________________ Ring is on method used to support the Morrison...
Today, most packaged watertube boilers follow one of the three...
The waste products from a sugar cane are used in a _______________...
Anthracite coal is very hard, has a high percentage of _________...
A power boiler is a steam boiler that operates at pressures greater...
The evaporator receives medium temperature __________ refrigerant.
A terminal reheat AHU delivers air at constant ______ degrees. A...
The general classification of superheaters includes ___________ and...
Sulfur in the soot then unites with moisture from condensation to...
_______________ are added to the boiler to prevent steam line and...
On HRT boilers, the shell is pitched 1 to 2 inches towards the back of...
Calcium and magnesium bicarbonate produce _____________ hardness.
Operating a boiler at temperatures 10° to 20°F above the...
There is no _____________ _________ ____ _________________ above the...
The minimum size for the connection in between the gauge glass and the...
The ____________ _________ mechanism on the high limit control call...
To remove oil from the boiler, __________ _________ and __________...
When a pump is used to circulate water though a heating system is a...
Water at its boiling point is considered a _____________ liquid.
What is the restriction in circulation due to a steam pocket inside...
Light domestic fuel oil is known as ________ ______ _____.
A ____________ is a gelatin like substance that has very small...
A supercritical boiler is a boiler that operates in excess of...
The ratio of the boiler's heat output to its heat input is...
A High pressure steam boiler must have a ASME ______ stamp.
Hardness is a measure of the ____________ and _______________ ions in...
Prior to entering a confined space, the minimum amount of oxygen in...
Rectifying phototube and lead sulfide phototube both prove flame in...
An ________ _________ mounted on the Water Column will sound an alarm...
The color of Cylinder containing R410A is __________.
All boiler heating surfaces are measured on the side blank the...
Boiler stop valves over 2" diameter must be...
To internally remove oxygen from the boiler, ____________ __________...
_____________prevents the tube end from being overheated and being...
That ratio of the maximum fuel input rate and the minimum input rate...
Unlike an infrared scanner, the ultraviolet scanner is no affected by...
A 26" x 48" x rectangular Duct is replaced with a round Duct. What is...
A refrigerant system using R-134a is running at 148 psi on the...
_______ _______________ make the final heat recovery from the boiler...
_____________ consist of relative close-spaced vertical tubes forming...
A three element feedwater regulator senses _________________...
The last form of over-pressure protection on the boiler, prior to...
The color of Cylinder containing R-123 is _________ ________ ...
The color of Cylinder containing R -134a is _________ ________ before...
The ratio of the maximum fuel input rate and the minimum fuel input...
Bent tubes are more __________ than straight tubes.
Flow of liquid in ad coil-type boiler is _______________ through the...
A centrifugal pump uses a ________ to convert velocity energy to...
The deaerator is an open feedwater heater that is used to remove...
A boiler horsepower is the evaporation into dry saturated steam of...
A low pressure steam boiler must have a ASME ____ stamp.
A method for testing the material for soundness without affecting the...
___________ ___________ is a device installed on the suction of a pump...
______________ usually caused cavities to form at grain boundaries in...
The color of Cylinder containing R-12 is _________ before 2020.
A turbine pump uses a __________ __________ to convert velocity to...
The presence of free oxygen in the boiler water will produce...
The temperature of a liquid minus 32 is the ____________ of the...
The National Board of Boiler and Pressure Vessel Repair requires an...
ASME code requires all boiler safety valves be stamped with a _____...
The "Three T's for proper fuel combustion are ___________,...
Name the 4 steps needed to perform regeneration on a zeolite water...
__________ ________ boilers recover the heat in the exhaust from a gas...
Number 4 fuel oil has _____________btu's per pound.
If a bulge in a boiler is not down more than ______ of its length, it...
There are _________ BTU's per gallon and _______________ BTU's per...
Natural gas has a heating value of ______ BTU's per ft³, or...
A water column is used to minimize water level ___________________in...
Two or more safety valves are required on a boiler with a heating...
__________________ coal burns with a yellow, smoky flame.
Galvanic corrosion occurs when ______________, metals are in direct...
In order for a black liquor boiler to sustain combustion, the liquor...
The two methods for deteminating the grindability of coal are...
Leaking safety valve should be ____________ to stop the leakage, never...
Leaking that occurs inside a centrifugal pump from the discharge to...
The color of Cylinder containing R-11 is _________ before 2020.
A disavantage of a HRT boiler is that scale or mud deposits on the...
The __________ __________ ________ takes air from the atmosphere, and...
For a company to a make qualified repairs to a safety valve they must...
The _________ __________ and _____________ _________ _______ sense...
The color of Cylinder containing R-401A is __________.
The temperature at which fuel oil will give off a vapor that will burn...
______________ acid is used to dissolve scale deposits during an acid...
_______________ is the transfer of heat from a liquid flowing over the...
The maximum voltage allowable on a control circuit is ______ volts.
The maximum adjustment to the setpoint of safety valve is ______...
If a tubesheet is corroded more than ______ percent of the original...
City Water pressure entering a building is 120 psi. The building is...
The number of tubes in each of the four passes is ____________ to...
The early watertube boilers followed some fire tube designs,being...
The chief heat producing elements in fuels are _______, _________, and...
Testing coal for moisture, percent volatile matter, fixed carbon, and...
A temperature sensor that measures the resistance of a platinum wire...
A 3" pressure-reducing valve has a ¾ inch bypass line. The...
The picture above is an example of a ______________ type safety valve
______________ is used on high pressure steam plants to absorb oxygen....
A ___________ Pump is a Positive Displacement Pump.
The __________ ______________ burner can burn almost any fuel oil, at...
Large amounts of _________________ in the exhaust flue gas can result...
When water is entrained in the steam it is called ___________ due to...
The safety valve capacity must be sufficient to relieve all the steam...
The percentage of excess air required to burn coal is about...
An induction AHU used High Pressure air flowing through the ________...
For proper combustion air into the boiler room, one square inch of...
Infrared flame scanners use a _______ __________ cell to detect the...
The pressure relief valve on a hot water boiler must be at least...
Coal gas is produced using the volatile matter from _______________...
Butane and propane are produced from the manufacturing of...
A 600 horsepower boiler's operating at 15 psi the boiler burners...
A pressure gauge installed 30 feet below the boiler drum reads 135...
The Economic boiler was an improvement on the HRT boiler. The economic...
A reciprocating pump has a water cylinder that is 18" diameter and 15"...
A ________ __________ is constructed of flat plates, referred to as a...
The percentage of excess air required to burn natural gas, fuel oil,...
Temporary hard water is water that contains large quantities of...
Permanently hard water is water that contains large quantities of...
Match the following
Match the following
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