Pipefitter Valves, Fittings, and Supports 4 — Questions and Answers
Question 1: A spring-loaded safety relief valve is set to open at 150 psi. What happens if the system pressure drops back below 150 psi?
- The valve remains open until manually reset
- The valve reseats automatically due to spring force (Correct answer)
- The valve must be replaced before reseating
- The valve opens further to equalize pressure
Correct answer: The valve reseats automatically due to spring force
Spring-loaded safety relief valves automatically reseat when system pressure drops below the set pressure, as the spring force closes the disc.
Question 2: Which type of pipe support is designed to allow controlled movement of a piping system in a specific direction while limiting movement in other directions?
- Rigid hanger
- Variable spring hanger
- Guided support (Correct answer)
- Anchor support
Correct answer: Guided support
Guided supports constrain lateral or rotational movement while allowing axial movement in a designated direction.
Question 3: A socket weld fitting is typically used for pipe sizes up to:
- 1/2 inch
- 2 inches
- 3 inches (Correct answer)
- 6 inches
Correct answer: 3 inches
Socket weld fittings are generally used for small-bore piping up to 3 inches (DN 80) in high-pressure applications.
Question 4: What is the primary purpose of a check valve in a piping system?
- To regulate flow rate
- To prevent backflow (Correct answer)
- To control pressure
- To allow manual shutoff
Correct answer: To prevent backflow
Check valves allow flow in one direction only and automatically prevent reverse flow (backflow) in the system.
Question 5: Which fitting is used to connect two pipes of different diameters in a straight run?
- Coupling
- Reducer (Correct answer)
- Elbow
- Tee
Correct answer: Reducer
A reducer connects two pipes of different diameters in-line and can be either concentric or eccentric depending on alignment requirements.
Question 6: A pipefitter must install a valve that can throttle flow with fine control and has a disc that moves perpendicular to the flow path. Which valve type is this?
- Gate valve
- Globe valve (Correct answer)
- Ball valve
- Butterfly valve
Correct answer: Globe valve
Globe valves use a disc that moves perpendicular to the seat and flow path, making them well-suited for throttling and flow regulation.
Question 7: What is the function of an eccentric reducer when used in a horizontal pump suction line?
- To increase flow velocity into the pump
- To prevent air pockets from forming at the top of the pipe (Correct answer)
- To reduce water hammer effects
- To allow thermal expansion of the piping
Correct answer: To prevent air pockets from forming at the top of the pipe
An eccentric reducer installed with the flat side up keeps the top of the pipe level, preventing air pockets that could cause cavitation in pump suction lines.
Pipefitter Valves, Fittings, and Supports 4
A spring-loaded safety relief valve is set to open at 150 psi.
What happens if the system pressure drops back below 150 psi?