1.
Which of these drawing symbols shows weld penetration depth in accordance with BS EN 22553?
Correct Answer
B.
2.
BS EN 288 and BS EN ISO 15614 are specifications for?
Correct Answer
C. Welding procedure approval
Explanation
BS EN 288 and BS EN ISO 15614 are specifications that pertain to welding procedure approval. These standards outline the requirements and guidelines for approving welding procedures, ensuring that they meet the necessary quality and safety standards. This approval process is crucial in ensuring the reliability and effectiveness of welding procedures in various industries.
3.
What determines the penetrating power of gammer rays?
Correct Answer
B. Type of isotope
Explanation
The penetrating power of gamma rays is determined by the type of isotope. Different isotopes emit gamma rays with varying energies, which directly affects their ability to penetrate materials. Isotopes with higher energy gamma rays have greater penetrating power and can pass through thicker materials. Therefore, the type of isotope being used is a crucial factor in determining the penetrating power of gamma rays.
4.
Which element has the greatest effect on the HAZ hardness of C-Mn steel?
Correct Answer
D. Carbon
Explanation
Carbon has the greatest effect on the HAZ hardness of C-Mn steel. Carbon is the main alloying element in steel and its concentration directly affects the hardness and strength of the material. Increasing the carbon content in steel increases its hardness, as carbon atoms occupy the spaces between iron atoms and prevent their movement, resulting in a stronger and harder material. Therefore, the higher the carbon content in C-Mn steel, the greater the effect on the hardness of the Heat Affected Zone (HAZ).
5.
Preheating a steel plate with a carbon equivalent (CEV) of 0.48 may be required to:
Correct Answer
B. Prevent excessive hardening in the HAZ
Explanation
Preheating a steel plate with a carbon equivalent (CEV) of 0.48 may be required to prevent excessive hardening in the Heat Affected Zone (HAZ). Preheating helps to slow down the cooling rate during welding, which reduces the risk of hardening and cracking in the HAZ. By maintaining a controlled temperature, the steel plate can be welded without causing brittleness or loss of toughness in the HAZ. This is important for ensuring the overall structural integrity and strength of the welded joint.
6.
A welder approval certificate should be withdrawn if:
Correct Answer
B. He has been absent from work for 7 months
Explanation
If a welder has been absent from work for 7 months, it indicates a prolonged period of absence without any valid reason. This absence may suggest a lack of commitment or interest in the job, which can be detrimental to the quality and safety of the welding work. Therefore, withdrawing the welder's approval certificate in such a situation is a reasonable action to ensure that only qualified and dedicated welders are allowed to perform welding tasks.
7.
In friction welding, the metal at the interface when the joining occurs is describes as being in the:
Correct Answer
C. Plastic state
Explanation
In friction welding, the metal at the interface when the joining occurs is described as being in the plastic state. This means that the metal has been heated to a temperature where it is soft and malleable, allowing it to undergo plastic deformation. During the friction welding process, the heat generated by the friction between the two surfaces causes the metal to soften and become plastic, enabling it to flow and form a solid bond between the two pieces being joined.
8.
A penertrameter (IQI) is used to measure the:
Correct Answer
D. Quality of the radiograpHic technique
Explanation
A penetrameter (IQI) is used to measure the quality of the radiographic technique. This device is used in radiography to assess the accuracy and reliability of the radiographic images produced. It helps in evaluating factors such as image resolution, contrast, and overall image quality. By using a penetrameter, technicians can ensure that the radiographic technique being used is capable of producing high-quality images, which are essential for accurate interpretation and diagnosis.
9.
Which of the following cutting methods is suitable for cutting stainless steel?
Correct Answer
A. Plasma
Explanation
Plasma cutting is suitable for cutting stainless steel because it uses a high-velocity jet of ionized gas to melt and remove the metal. This method provides a precise and clean cut, making it ideal for stainless steel which is known for its hardness and resistance to corrosion. Oxy-acetylene and oxy-propane cutting methods may not be as effective for stainless steel due to its high melting point. The choice of cutting method also depends on the thickness of the stainless steel being cut.
10.
Which of the following would be classed as the most serious type of defect?
Correct Answer
C. Surface breaking lack of sidewall fusion
Explanation
A surface breaking lack of sidewall fusion is considered the most serious type of defect because it affects the structural integrity of the weld. This defect occurs when there is a lack of fusion between the sidewall of the weld joint and the base metal, resulting in a weak bond. This type of defect can lead to cracks, leaks, and ultimately failure of the welded component, making it a critical concern in welding applications.
11.
Ultrasonic testing has an advantage over other NDT methods for the detection of:
Correct Answer
A. Lack of sidewall fusion
Explanation
Ultrasonic testing is advantageous for detecting lack of sidewall fusion because it uses high-frequency sound waves to penetrate materials and identify internal flaws. This method can effectively detect discontinuities or gaps between the sidewall and the fusion zone, ensuring the quality and integrity of the weld joint. Other NDT methods may not be as sensitive or accurate in detecting this specific flaw, making ultrasonic testing the preferred choice in such cases.
12.
Exceeding the maximum interpass temperature specified for a C-Mn steel weld joint may give:
Correct Answer
C. Lower toughness
Explanation
Exceeding the maximum interpass temperature specified for a C-Mn steel weld joint can result in lower toughness. This is because high temperatures can cause grain growth, leading to a coarser microstructure and reduced toughness. Lower toughness means that the weld joint will be more susceptible to cracking or failure under stress. Therefore, it is important to adhere to the specified interpass temperature limits to maintain the desired toughness and ensure the integrity of the weld joint.
13.
MIG/MAG welding has a tendency to give lack of sidewall fusion when:
Correct Answer
D. Dip transfer
Explanation
Dip transfer is a type of MIG/MAG welding where the electrode touches the weld pool and creates a short circuit. This method is more prone to causing a lack of sidewall fusion compared to other transfer conditions. In dip transfer, the electrode tends to create a larger weld pool, which can result in insufficient heat reaching the sidewalls of the joint, leading to incomplete fusion. Therefore, when dip transfer is used in MIG/MAG welding, there is a higher likelihood of experiencing a lack of sidewall fusion.
14.
The temperature range over which a steel goes from having high to low toughness is called the:
Correct Answer
D. Transition temperature
Explanation
The transition temperature refers to the temperature range at which a steel undergoes a change in toughness, shifting from high to low. This temperature range is crucial as it indicates the point where the steel's mechanical properties, such as ductility and toughness, significantly alter. It is an essential parameter to consider in engineering applications to ensure that the steel can withstand the required conditions without failure. The other options, critical transformation temperature, ductility dip temperature, and bi-modal temperature, do not specifically address the change in toughness and are not commonly used terms in relation to steel properties.
15.
For SAW, what is the effect of raising arc voltage but keeping all other parameters the same?
Correct Answer
A. Weld bead width will increase
Explanation
Raising the arc voltage in SAW (Submerged Arc Welding) while keeping all other parameters the same will result in an increase in weld bead width. The arc voltage directly affects the heat input during the welding process. By increasing the arc voltage, more heat is generated, leading to a wider weld bead. This wider bead can be beneficial in certain applications where a larger weld size is desired for strength or aesthetic reasons.
16.
Changing an essential variable beyond the allowed limits for a qualified welding procedure:
Correct Answer
D. All of the above
Explanation
Changing an essential variable beyond the allowed limits for a qualified welding procedure can have several consequences. Firstly, it may change the mechanical properties of the joint, which can impact its strength and durability. Secondly, it may adversely affect the quality of the weld, leading to defects or failures. Lastly, such changes will require a new welding procedure to be approved, as the original procedure may no longer be valid or safe. Therefore, all of the above statements are true.
17.
With reference to the various grades of stainless steels which of the following statements is true?
Correct Answer
D. Only certain grades can be used for service at very low temperatures
Explanation
Only certain grades of stainless steels can be used for service at very low temperatures because these grades have been specifically designed to withstand the extreme cold conditions. Other grades may become brittle or lose their mechanical properties at low temperatures, making them unsuitable for such applications. Therefore, it is important to select the appropriate grade of stainless steel based on the intended service temperature range.
18.
Which of the following AWS A5.1 electrodes has a rutile covering:
Correct Answer
D. E 6013
Explanation
The AWS A5.1 electrode with a rutile covering is E 6013.
19.
Welds made with very high heat input will show a reduction in:
Correct Answer
B. Notch toughness
Explanation
Welds made with very high heat input will show a reduction in notch toughness. Notch toughness refers to the ability of a material to withstand stress concentrations at a notch or a small crack. High heat input during welding can result in the formation of coarse grains and a decrease in the material's ability to resist crack propagation. This reduction in notch toughness can make the weld more susceptible to failure or cracking in the presence of stress concentrations.
20.
During PWHT of a complex fabrication, it is heated to the soak temperature at a much faster rate than specified by the procedure. This may:
Correct Answer
D. Cause distortion
Explanation
Heating a complex fabrication to the soak temperature at a faster rate than specified by the procedure can cause distortion. This is because the rapid heating can lead to uneven expansion and contraction of the material, causing it to warp or deform. The slower heating rate specified in the procedure allows for more uniform expansion and contraction, reducing the risk of distortion.
21.
When MAG welding in dip transfer (a short-circuiting mode) spatter can be reduced by:
Correct Answer
A. Using inductance
Explanation
Using inductance can reduce spatter in MAG welding in dip transfer mode. Inductance helps control the welding current by slowing down the rate at which the current rises and falls. This smoother current flow reduces the likelihood of short-circuits and therefore reduces spatter. By using inductance, the welding process becomes more stable and controlled, resulting in less spatter and a higher quality weld.
22.
Repair welding of in-service plant and equipment may be more difficult than making repairs during initial fabrication because:
Correct Answer
D. All of the above
Explanation
Repair welding of in-service plant and equipment may be more difficult than making repairs during initial fabrication because the material may be contaminated, access to the repair area may be difficult, and positional welding may be needed. Contamination of the material can affect the quality of the repair and make it more challenging. Limited access to the repair area can make it harder to reach and work on the damaged area. Positional welding may be required when the equipment cannot be moved or positioned easily, making the repair process more complex. Therefore, all of the given reasons contribute to the difficulty of repair welding in comparison to initial fabrication.
23.
For gammer radiography of a steel weld at 35mm thickness, the recommended isotope is:
Correct Answer
C. Iridium 192
Explanation
Iridium 192 is the recommended isotope for gamma radiography of a steel weld at 35mm thickness. This is because Iridium 192 has a suitable half-life and energy level for this type of radiography. It can penetrate through the steel weld and provide clear images of any defects or irregularities. Thulium 170, Ytterbium 169, and Cobalt 60 may not be as effective in this specific application.
24.
The sensitivity of a radiograph is assessed:
Correct Answer
B. By using an image quality indicator (IQI)
Explanation
The sensitivity of a radiograph is assessed by using an image quality indicator (IQI). An IQI is a test object that is placed on the radiograph and contains various thicknesses of metal or wire. When the radiograph is developed, the IQI is used to measure the density of the image produced. This allows for the evaluation of the sensitivity of the radiograph, as it indicates how well the radiograph is able to detect and differentiate between different levels of density or thickness in the object being imaged. The densitometer is a device used to measure the density of the developed radiograph, but it is not specifically used to assess the sensitivity. The KVA used and the source/tube to work standoff distance are not directly related to the assessment of sensitivity.
25.
A transverse tensile test from a Weld Procedure Approval Record (WPAR) test plate is used to measure:
Correct Answer
B. Tensile strength of the joint
Explanation
A transverse tensile test from a Weld Procedure Approval Record (WPAR) test plate is used to measure the tensile strength of the joint. This test involves applying a pulling force to the joint in a transverse direction, perpendicular to the direction of the weld. By measuring the maximum force applied before the joint breaks, the tensile strength of the joint can be determined. This is important in assessing the quality and integrity of the weld joint, as it indicates the maximum load the joint can withstand before failure.
26.
The highest and lowest heat input positions are considered to be:
Correct Answer
D. PF highest; PG lowest.
Explanation
The correct answer is PF highest; PG lowest. This means that the highest heat input position is PF, while the lowest heat input position is PG.
27.
What type of covering will an electrode have that is suitable for welding 60mm C-Mn steel and can give good weld metal toughness at -50ºC?
Correct Answer
B. Basic
Explanation
The correct answer is Basic. Basic electrodes have a high level of basic compounds in their coating, which helps to reduce impurities and increase the toughness of the weld metal. This makes them suitable for welding 60mm C-Mn steel and providing good weld metal toughness at -50°C.
28.
The dip transfer or short-circuiting mode of metal transfer used for MIG/MAG welding is characterized by:
Correct Answer
B. Being suitable for positional welding
Explanation
The dip transfer or short-circuiting mode of metal transfer used in MIG/MAG welding is characterized by being suitable for positional welding. This means that it is effective for welding in various positions, such as vertical, overhead, or horizontal, without compromising the quality of the weld. This mode of transfer allows for better control and stability during the welding process, ensuring that the weld is accurate and consistent regardless of the position.
29.
Carbon equivalent values (CEV) are used to determine how to avoid the risk of:
Correct Answer
A. Hydrogen cracking
Explanation
Carbon equivalent values (CEV) are used to determine how to avoid the risk of hydrogen cracking in welding. Hydrogen cracking, also known as cold cracking or delayed cracking, occurs when hydrogen atoms become trapped in the weld metal and cause cracks to form. By calculating the CEV, which takes into account the carbon content and other alloying elements in the base metal, welders can determine the susceptibility to hydrogen cracking and adjust their welding parameters accordingly. This helps in selecting appropriate preheating, post-weld heat treatment, and filler material to minimize the risk of hydrogen cracking.
30.
When two different material types are welded together the joint is referred to as:
Correct Answer
B. A transition joint
Explanation
A transition joint is the correct answer because it refers to a joint where two different material types are welded together. This type of joint is used to connect materials with different properties or characteristics, allowing for a smooth transition between them. It is commonly used in various industries, such as automotive and construction, where different materials need to be joined together to achieve desired structural or functional properties.