Ramsay Test Piping and Plumbing — Questions and Answers
Question 1: Which fitting is used to connect two pipes of different diameters in a straight run?
- Elbow
- Tee
- Reducer or reducing bushing (Correct answer)
- Union
Correct answer: Reducer or reducing bushing
A reducer (or reducing bushing) transitions from one pipe diameter to a smaller one in a straight line. Elbows change direction, tees add a branch outlet, and unions allow disassembly of a straight joint.
Question 2: What is the function of a check valve in a piping system?
- To regulate flow to a precise set rate
- To allow flow in one direction only and automatically prevent backflow (Correct answer)
- To relieve excess system pressure to atmosphere
- To isolate a section of pipe for maintenance
Correct answer: To allow flow in one direction only and automatically prevent backflow
Check valves (also called non-return valves) open under forward flow and close automatically when flow reverses, protecting pumps, compressors, and other equipment from backflow damage. Flow control is a needle/globe valve function; pressure relief is a safety/relief valve function; isolation is a ball or gate valve function.
Question 3: Pipe schedule numbers (Schedule 40, Schedule 80, etc.) refer to:
- The outside diameter of the pipe
- The material grade or alloy of the pipe
- The wall thickness relative to the pipe's nominal size (Correct answer)
- The maximum allowable operating temperature
Correct answer: The wall thickness relative to the pipe's nominal size
Schedule numbers define wall thickness — a higher schedule means thicker walls and a higher pressure rating. For any given nominal pipe size (NPS), the outside diameter stays constant across schedules; only the wall thickness and therefore inside diameter change.
Question 4: When applying Teflon (PTFE) tape to NPT (National Pipe Taper) male threads, the tape should be wrapped:
- Clockwise when viewed from the threaded end — the same direction as thread engagement (Correct answer)
- Counter-clockwise regardless of thread orientation
- In either direction — orientation does not affect sealing
- Clockwise for 1 full wrap only, regardless of thread count
Correct answer: Clockwise when viewed from the threaded end — the same direction as thread engagement
Wrapping tape in the direction of thread engagement (clockwise when looking at the male end) causes the tape to tighten and seat when the fitting is threaded in. Wrapping the opposite direction causes the tape to unravel and bunch as the fitting is turned, destroying the seal.
Question 5: A technician hears repeated banging in a piping system whenever a solenoid valve closes quickly. This condition is called water hammer. The best corrective action is to:
- Increase system operating pressure to suppress the pressure wave
- Install a water hammer arrestor or replace the valve with a slow-closing type (Correct answer)
- Replace all elbows with tee fittings to reduce flow velocity
- Upgrade pipe to a higher schedule throughout the affected run
Correct answer: Install a water hammer arrestor or replace the valve with a slow-closing type
Water hammer is caused by the sudden deceleration of fluid when a valve closes rapidly, creating a pressure wave. Arrestors absorb the wave with an internal piston and spring; slow-closing valves prevent the sudden fluid stoppage that generates the wave in the first place.
Question 6: What is the primary maintenance advantage of installing a union fitting in a piping system?
- It increases the rated pressure of the pipe joint
- It allows the joint to be broken and reassembled without cutting or rotating the pipe (Correct answer)
- It reduces turbulence and friction loss at the connection point
- It automatically compensates for thermal expansion in the pipe run
Correct answer: It allows the joint to be broken and reassembled without cutting or rotating the pipe
A union uses three pieces (two end fittings and a central nut) that can be disconnected and reconnected without rotating the attached pipe. This makes it essential near equipment like pumps, strainers, and valves that need to be removed for maintenance.
Ramsay Test Piping and Plumbing
Which fitting is used to connect two pipes of different diameters in a straight run?