Blrs 6021_Pressure Safety Devices

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Question 1: A spring-loaded device that acts as a safety valve in gas service and as a relief valve in liquid service is called a: A - Pilot-operated pressure-relief valve B - Water sealed safety-relief device C - Relief valve D - Safety-relief valve _______________________________________________

Question 2: A pilot-operated pressure relief valve is a valve in which the major relieving device is combined with, and is controlled by a:

A - Self-actuated gate valve B - Water sealed safety-relief valve C - Manually operated pressure-relief valve D - Self-actuated pressure-relief valve _______________________________________________

Question 3: The type of safety valve shown in the illustration seen here is a:

A - Conventional safety-relief valve B - Power-actuated pressure-relief valve C - Pilot-operated pressure-relief valve D - Water sealed safety-relief valve _______________________________________________

Question 4: Power-actuated relief valves can be used instead of code-required safety valves as they do essentially the same job. A - True B - False _______________________________________________

Question 5: The pressure safety device in which the major relieving device is combined with, and is controlled by a self-actuated pressure-relief valve is the:

A - Pilot-operated pressure-relief valve B - Water sealed safety-relief device C - Safety-relief valve D - Power-actuated pressure-relief valve _______________________________________________

Question 6: A relief valve is a spring-loaded device that begins to open when the inlet pressure reaches set pressure, overcomes the spring force, and begins to lift the disk off the seat. It is used in: A - Gas service B - Liquid service C - Steam service D - All of the above _______________________________________________

Question 7: In a pilot-operated safety-relief valve, pressure is exerted on both sides of the main valve. The valve is held closed because the dome surface area is: A - Larger than the system side B - Smaller than the system side C - The same size as the system side D - None of the above

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Question 8: Inadvertent contact between the lifting cam and the spindle nut of a pressure relief valve may be the result of: A - Vibration and pulsing pressure B - Incorrectly adjusting lifting gear C - Damaged springs D - Rough handling _______________________________________________

Question 9: Pilot-operated safety-relief valves are primarily used: A - In general refinery process service B - Where chemical compatibility of the process fluid with the diaphragms is questionable C - Where there is low differential between normal operating pressures and set pressure of the valve D - In viscous liquid service _______________________________________________

Question 10: The operational characteristics of a conventional safety-relief valve are directly affected by changes in the: A - Process flow B - Valve outlet pressure C - Backpressure on the valve D - Tension on the main spring _______________________________________________

Question 11: Pilot-operated safety-valves are not used: A - In viscous liquid service B - Where large relief areas at high set pressure are required C - On large, low-pressure storage tanks D - Where very short blowdown is required _______________________________________________

Question 12: A pressure gauge, a try cock, a free vent, or a suitable indicator should be inserted _____________ a rupture disk device installed at the ___________ of a pressure-relief valve and the valve itself to detect disk rupture or leakage.

A - beside; outlet B - between; inlet C - between; outlet D - beside; inlet _______________________________________________

Question 13: Damaged flanges and misaligned valve parts of a pressure-relief valve can result from:

A - Vibration and pulsating pressure B - Leakage C - Rough handling D - Incorrect calibration _______________________________________________

Question 14: Which pressure relief valve problem could cause the disk to rub against the seat, resulting in leakage? A - Incorrect calibration B - Vibrating and pulsating pressure C - An incorrectly adjusted lifting gear D - Damaged springs _______________________________________________

Question 15: If you were designing a system where any superimposed backpressure is constant and any built-up backpressure will not exceed 10% of the set pressure, the type of safety pressure device that you would include in your design should be a: A - Conventional safety-relief valve B - Water-sealed safety-relief valve C - Rupture disk D - Power-actuated pressure-relief valve _______________________________________________

Question 16: The safety-relief device that is referred to as a non-reclosing pressure relief device is a: A - Pilot-operated pressure-relief valve B - Relief valve C - Water sealed safety-relief device D - Rupture disk _______________________________________________

Question 17: Rupture disks are used to protect:

A - The upstream side of pressure valves against corrosion by the system fluid B - The downstream side of pressure relief valves against atmospheric corrosion C - Pressure relief valves against plugging or clogging by viscous fluids D - All of the above _______________________________________________

Question 18: The safety valve has a valve disk that is held firmly on its seat by: A - A carbon-steel casing welded directly to the pipe B - Two adjustable nuts that are equipped with locknuts C - The pressure of the process flow D - The pressure of a heavy coil spring _______________________________________________

Question 19: When maximum pressure is reached, the metal membrane of a rupture disk fails and: A - Blows apart in fragments B - Dissolves C - Gradually relieves the pressure D - Peels open _______________________________________________

Question 20: The force of the pressure acting on the safety valve disk is a function of: A - Seat diameter B - Spring tension C - Disk area D - Percentage of valve opening