CSWIP Question 5

A welding inspector typically focuses on inspecting the quality of welds and ensuring that they meet the required standards. This includes checking the condition of the parent material, checking the condition of the consumables, and verifying the calibration certificates of the equipment used. However, measuring residual stress is not typically a duty performed by a welding inspector. Residual stress is a complex measurement that requires specialized equipment and expertise, usually performed by a metallurgist or stress engineer.

The term given for the area of a welded joint outside the weld metal that has undergone microstructural changes is the heat affected zone. This zone is affected by the heat from the welding process, causing changes in its microstructure, such as grain growth and hardness variations. The weld zone refers specifically to the area where the weld metal is located, and the fusion zone refers to the region where the base metal and the weld metal have fused together. Therefore, the correct term for the given description is the heat affected zone.

In welding, the position of the weld refers to the orientation of the joint relative to the ground. PA stands for "flat position," where the weld is performed horizontally. In this position, the weld metal is deposited directly onto the joint, resulting in a higher deposition rate compared to other positions. This is because the weld pool is more stable, allowing for better control and a higher volume of weld metal to be deposited. Therefore, under most conditions, the PA position will deposit the most weld metal.

Deposition rate is the correct term used for the amount of weld metal deposited per minute in an arc welding process. It refers to the rate at which the filler metal is added to the joint during welding. This term is important in determining the productivity and efficiency of the welding process, as it indicates how quickly the weld can be completed and how much material is being added. The deposition rate can vary depending on factors such as the welding technique, welding parameters, and the type and size of the filler metal being used.

When measuring the welding parameters with the MMA welding process, it is important for the welding inspector to measure the voltage as close to the welding arc as possible. This is because the voltage at the welding arc directly affects the quality of the weld. By measuring the voltage at this point, the inspector can ensure that the correct voltage is being used for the welding procedure, which is crucial for approving the welding procedure. Measuring the voltage anywhere along the welding cable or from the voltmeter on the welding plant may not provide an accurate representation of the voltage at the welding arc. Similarly, measuring the voltage as near to the welding terminals as possible may not accurately reflect the voltage at the welding arc.

A double-U butt weld preparation is usually the most susceptible to lack of sidewall fusion during the manual arc process. This is because the shape of the double-U butt creates a larger gap between the two pieces of metal, making it more difficult for the heat and filler metal to reach the sidewalls and fuse them together properly. As a result, there is a higher risk of incomplete fusion and potential defects in the weld joint.

The leg length of a fillet weld refers to the distance from the root to the toe. This measurement is important in determining the strength and integrity of the weld joint. The root is the deepest part of the weld, while the toe is the outer edge. By measuring the distance between these two points, one can assess the quality and effectiveness of the weld. The other options provided in the question, such as the distance from the toe to face and 0.7 of the design thickness, are not accurate descriptions of the leg length of a fillet weld.

The correct answer is "The distance from the root to the face centre." In a fillet weld with equal leg lengths, the thickness is measured from the root, which is the point where the weld intersects the base metal, to the face center, which is the middle point of the weld. This measurement determines the overall thickness of the weld and is important for ensuring the strength and integrity of the joint.

The term "crater pipe" refers to a shrinkage defect found in the weld crater. In welding, a crater is the depression or cavity that forms at the end of a weld bead. During the solidification process, if there is insufficient molten metal to fill the crater, a shrinkage defect can occur, resulting in a void or pipe-like structure in the weld crater. This defect can weaken the weld and compromise its integrity. Therefore, "crater pipe" is used to describe this specific type of shrinkage defect found in the weld crater.

In this situation where the specification does not mention the requirements for visual inspection, it is important to seek advice from a higher authority. This is because the lack of specific instructions can lead to ambiguity and uncertainty regarding the correct procedure for visual inspection. By consulting with a higher authority, one can obtain guidance and clarification on how to proceed with the inspection in a way that aligns with the overall requirements and objectives.

Deep weld craters/crater cracks are most likely to be caused by a welder with a poor technique. This is because deep weld craters occur when the welder does not properly control the welding arc and allows it to dwell in one spot for too long, resulting in excessive heat input. This can lead to the formation of a deep crater, which is prone to cracking. Therefore, a welder with poor technique is more likely to cause deep weld craters/crater cracks compared to copper inclusions or hydrogen cracks.

None planar defects are not usually as significant as planar defects. This means that while they may still affect the integrity of the weld, they are generally considered to be less serious or less critical. Planar defects, on the other hand, refer to defects that occur in a two-dimensional plane, such as cracks or lack of fusion, and are typically more severe and require immediate repair or removal of the entire weld.

A burn through occurs when the root face, which is the gap between the two pieces being welded, is too small. This can lead to excessive heat being concentrated in a small area, causing the metal to melt and burn through. A root gap that is too small or a travel speed that is too fast can also contribute to burn through, but the most likely cause is a root face that is too small.

The term weld junction refers to the boundary between the fusion zone and the heat-affected zone (HAZ). This boundary represents the transition area where the weld metal and the surrounding parent metal meet. It is at this junction that the metallurgical changes occur due to the heat generated during the welding process. The weld junction is an important area to consider in welding as it can affect the overall strength and integrity of the weld.

The correct answer is "Combinations between two different weld types." This means that compound welds are formed by combining two different types of welds. This could include a combination of butt and fillet welds, or joints made by different welding processes. Therefore, compound welds always involve a mixture of different weld types.

The strength of a fillet weld is primarily controlled by the design throat thickness. The design throat thickness refers to the theoretical minimum thickness of the weld, which is calculated based on the size of the weld and the angle between the two joining surfaces. It is an important factor in determining the load-carrying capacity of the weld joint. Leg length and actual throat thickness may also have some influence on the strength of the weld, but the design throat thickness is the most significant factor.

The correct answer is "None of the above" because none of the mentioned welding processes/techniques are suitable for repairing localized porosity in a butt weld. MMA (Manual Metal Arc) and Mechanised MAG (Metal Active Gas) are not ideal for repairing porosity as they do not provide sufficient control over the welding process. Submerged arc welding is also not suitable as it is typically used for deep penetration and high deposition rate, which may not be necessary for repairing localized porosity. Therefore, an alternative welding process or technique would need to be used for this specific repair.

Root concavity refers to a depression or indentation at the root of a weld joint. This defect is caused by excessive root grinding, which removes too much material and creates a gap between the base metal and the weld metal. Additionally, excessive back purge pressure can push gas into this gap, further exacerbating the concavity. Therefore, the correct answer is that root concavity is caused by both excessive root grinding and excessive back purge pressure.

The duties of a welding inspector include supervising welders, writing procedures, and qualifying welders. These responsibilities ensure that the welding work is carried out properly and meets the required standards. By supervising welders, the inspector can ensure that they are following the correct techniques and procedures. Writing procedures is important as it provides clear guidelines for welders to follow, ensuring consistency and quality in their work. Qualifying welders involves assessing their skills and abilities to ensure they are competent to perform the required welding tasks. Therefore, all of the above options are considered duties of a welding inspector.

The correct answer is "None of the above can be selected – specification requirements unknown." This means that there is no specific requirement or guideline regarding the toes of a weld when inspecting a critical component. The specification requirements are unknown, so it is not possible to determine what should be done with the toes of the weld.