1.
Why shouldn't you wear nylon clothing when welding?
Correct Answer
D. Because it can catch fire easily and melt to your skin.
Explanation
Nylon is a synthetic material that is known to be highly flammable. When exposed to high temperatures, such as those encountered during welding, nylon clothing can catch fire and melt. This poses a significant safety hazard as molten nylon can cause severe burns to the skin. Therefore, it is essential to avoid wearing nylon clothing when engaging in activities like welding, where there is a risk of exposure to intense heat and sparks.
2.
What two items on a MIG welder would need to be changed when changing from a 0.9mm mild steel wire electrode to a 1.2mm mild steel wire electrode?
Correct Answer
B. Contact tip and drive rollers.
Explanation
When changing from a 0.9mm mild steel wire electrode to a 1.2mm mild steel wire electrode on a MIG welder, the contact tip and drive rollers would need to be changed. The contact tip is responsible for guiding the wire electrode to the welding point, and since the diameter of the wire has changed, a different contact tip is required to ensure proper alignment. Similarly, the drive rollers are responsible for feeding the wire electrode through the welder, and since the diameter of the wire has changed, the drive rollers need to be adjusted or replaced to accommodate the larger diameter.
3.
What is an "inert gas" as used in Metal Inert Gas (MIG) Welding?
Correct Answer
C. A gas that does not chemically react with other elements to help produce a quality weld.
Explanation
An "inert gas" used in Metal Inert Gas (MIG) Welding is a gas that does not chemically react with other elements. This is important because it helps produce a quality weld by preventing any unwanted reactions or contamination during the welding process. By using an inert gas, the weld zone remains stable and free from any chemical reactions that could weaken the weld or introduce impurities.
4.
Stick (Arc) Welding uses a coated electrode; what is the purpose of this coating?
Correct Answer
D. The coating produces a protective gas to prevent porosity.
Explanation
The purpose of the coating on a stick (arc) welding electrode is to produce a protective gas that prevents porosity. Porosity refers to the presence of small holes or voids in the weld, which can weaken its strength and integrity. The coating on the electrode generates a gas that shields the molten weld pool from the surrounding atmosphere, preventing the formation of these voids. This helps to ensure a stronger and more reliable weld.
5.
What treatment is recommended after welding stainless steel?
Correct Answer
C. Apply the pickling paste.
Explanation
After welding stainless steel, it is recommended to apply the pickling paste. This is because welding stainless steel can cause the formation of oxides on the surface, which can lead to corrosion. Applying the pickling paste helps to remove these oxides and restore the stainless steel's corrosion resistance. It is an effective treatment method to ensure the longevity and durability of the stainless steel after welding.
6.
When performing a fillet weld between two pieces of 5mm thick mild steel, what is the recommended size (leg length) of the weld? (when not given a size)
Correct Answer
A. 5mm
Explanation
When performing a fillet weld between two pieces of 5mm thick mild steel, the recommended size (leg length) of the weld is 5mm. This means that the length of each leg of the weld should be 5mm. A fillet weld is a type of weld that joins two pieces of metal at a right angle, and the leg length refers to the distance from the root of the weld to the toe. In this case, since the thickness of the steel is 5mm, it is recommended to have a leg length of 5mm for the weld.
7.
What is the minimum recommended filter shade on a welding helmet to protect your eyes?
Correct Answer
A. Shade 10
Explanation
The minimum recommended filter shade on a welding helmet to protect your eyes is Shade 10. This shade provides enough protection to shield your eyes from the intense light and harmful radiation produced during welding. A lower shade number may not provide sufficient protection, while a higher shade number may make it difficult to see the welding process clearly.
8.
What type of weld would you do to form a T shape between two pieces of flat bar?
Correct Answer
B. Fillet
Explanation
To form a T shape between two pieces of flat bar, a fillet weld would be used. A fillet weld is a type of weld that is used to join two pieces of metal at a right angle, forming a T shape. It is commonly used in structural applications where strength and stability are required. The fillet weld is formed by creating a triangular-shaped bead of weld metal along the joint, providing a strong and durable connection between the two flat bars.
9.
What type of respiratory protection is the minimum required when welding?
Correct Answer
B. P2 Respirator
Explanation
The minimum required respiratory protection when welding is a P2 Respirator. This type of respirator is specifically designed to filter out fine particles such as welding fumes, which can be harmful to breathe in. The P2 Respirator provides a higher level of protection compared to a dust mask, and it is necessary to ensure the safety and health of the welder. A hazmat suit is not required for welding as it is designed for protection against hazardous materials in a different context.
10.
Which of the following is an advantage of MIG welding?
Correct Answer
C. It takes less operator skill than other weld types.
Explanation
MIG welding has the advantage of requiring less operator skill compared to other types of welding. This is because MIG welding uses a wire electrode that is continuously fed, making it easier to control and manipulate the welding process. It also provides better control over the heat input, resulting in less distortion and warping of the metal being welded. This makes MIG welding a preferred choice for beginners or those who have limited welding experience.
11.
How would you prepare a 25mm low carbon steel flat bar for a butt weld?
Correct Answer
D. Grind a double V preparation
Explanation
To prepare a 25mm low carbon steel flat bar for a butt weld, the correct approach is to grind a double V preparation. This involves grinding a V-shaped groove on both sides of the bar, creating a channel for the weld to fill. This preparation ensures better penetration and a stronger weld joint.
12.
Which weld procedure is safe to perform in wet conditions?
Correct Answer
E. None of the Above
Explanation
Welding in wet conditions is highly dangerous regardless of the welding method. Wet conditions increase the risk of electric shock and other hazards. Therefore, it is important to avoid performing welding procedures like Oxy Welding, Arc Welding, MIG Welding, and TIG Welding in wet conditions. Always ensure a dry and safe environment before welding.
13.
How would you prepare heavily rusted mild steel for welding?
Correct Answer
B. Grind back to bare metal.
Explanation
To prepare heavily rusted mild steel for welding, it is necessary to grind back to bare metal. This is because welding over rusted metal can result in weak and unreliable welds. Grinding back to bare metal removes the rust and any other contaminants, ensuring a clean surface for proper welding.
14.
If you found a tool to be faulty or dangerous, what should you do?
Correct Answer
C. Take it out of service, report it, and if required, tag it.
Explanation
If you find a tool to be faulty or dangerous, the correct course of action is to take it out of service to prevent any potential harm or accidents. Additionally, it is important to report the issue to the appropriate authorities or supervisors so that they can address the problem and take necessary actions to fix or replace the tool. If required, tagging the tool can help to clearly indicate that it is not safe for use, ensuring that others are aware of the issue and do not attempt to use it.
15.
Which of the following welding processes uses a non-consumable tungsten electrode?
Correct Answer
B. TIG Welding
Explanation
TIG Welding, which stands for Tungsten Inert Gas welding, is a welding process that uses a non-consumable tungsten electrode to produce the weld. The tungsten electrode is used to carry the welding current and create the arc that melts the base metal. Unlike other welding processes where the electrode melts and becomes part of the weld (consumable electrode), in TIG welding, the tungsten electrode remains intact and does not melt.