Piping Systems and Valves Flashcards
7 cards from real CARO practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 7 Piping Systems and Valves flashcards as text
What is the primary purpose of a hand expansion valve (HEV) in an ammonia refrigeration system?
Answer: To manually control refrigerant flow into a vessel or evaporator
A hand expansion valve is a manually operated valve used to throttle or control refrigerant flow into a vessel or evaporator, not an automatic device.
Which type of valve is most commonly used as a stop valve (shutoff valve) in ammonia refrigeration piping?
Answer: Gate valve
Gate valves are the most common stop/shutoff valves in ammonia refrigeration systems because they provide full-bore flow with minimal pressure drop when fully open.
What does a check valve do in a refrigeration piping system?
Answer: Prevents refrigerant from flowing backward in the piping
A check valve allows refrigerant to flow in only one direction, preventing reverse flow that could damage compressors or disrupt system operation.
A pressure relief valve on a refrigeration vessel is required to discharge to:
Answer: A safe outdoor location or treatment system per code
Pressure relief valves must discharge to a safe outdoor location or an approved treatment/containment system to protect personnel and comply with codes such as IIAR and ASHRAE 15.
What is the function of a solenoid valve in a refrigeration system?
Answer: To electrically open or close refrigerant flow on demand
A solenoid valve uses an electromagnetic coil to open or close the valve electrically, allowing automated control of refrigerant flow in response to a control signal.
What material is most commonly used for ammonia refrigeration piping in industrial systems?
Answer: Carbon steel pipe
Carbon steel pipe is the standard material for ammonia refrigeration because ammonia is incompatible with copper, brass, and zinc, which corrode rapidly in its presence.
What is the purpose of a fusible plug installed on a refrigeration vessel?
Answer: To melt and release refrigerant if vessel temperature reaches a dangerous level
A fusible plug contains a low-melting-point alloy that melts at a set temperature, releasing refrigerant to prevent vessel rupture due to fire or extreme heat.