Questions and Answers
What is the function of pressure relief valves?
To automatically open and relieve pressure
How many different types of pressure relief devices are defined in ASME PTC-25?
11
Why is it important to use accurate terms to describe each type of pressure relief valve?
To create uniformity in naming
According to ASME BPVC I, Part PG-73.1.4, which definitions relating to pressure relief devices apply?
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How are pressure relief valves designed to actuate?
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What do all pressure relief valves have in common?
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What is the acronym PRV used for in this chapter?
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According to ASME BPVC I, how many pressure relief valves should a boiler have if it has more than 500 ft2 of bare tube water-heating surface?
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What material are cast iron and bronze safety valves commonly made of?
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How does a safety valve work when the steam pressure reaches the set point pressure?
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What is used to adjust the point at which the safety valve will lift and relieve the pressure?
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What happens if the safety valve is opened without pressure in the boiler?
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Why is a huddling chamber formed in a safety valve disc?
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What does ASME BPVC Section I, Part PG-73 prohibit for valves with superheaters operating over 230°C?
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"The set pressure of a superheater safety valve must take into consideration that the steam pressure will drop as it flows from the steam drum to the superheater outlet." - What is the reason behind this statement?
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Why are superheater and reheater pressure relief valves required to be made of steel or alloy steel according to ASME BPVC Section I, Part PG-68?
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What happens if a superheater PRV is set to the same pressure as drum PRVs?
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What causes the safety valve to pop wide open?
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What is the blowdown of a pressure relief valve?
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What happens when the blowdown adjusting ring completely blocks off the huddling chamber escape ports?
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How is the PRV set pressure adjusted?
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What should be done before adjusting the pressure at which the safety valve opens?
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What is the purpose of a discharge pipe for a safety valve?
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