The two safety valves have the same model, but their capacity at 10% over pressure differs – are they the same safety valve?
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This post was last edited by fpspaul on 2016-7-21 09:23. As the title suggests, it involves 2 safety valves; their model, structure, set pressure, test pressure, and all other specifications are identical (FARRIS ENGINEERING)； TYPE：26EA10L-140/SP ； SIZE AND ORIFICE ：1 E 2 ； SET PRESS: 7 BARG ； COLD DIFF. TEST PRESS: 7 BARG;） That means the capacity is 10% higher at increased pressure. Are these safety valves of the same model? Or, can they be used interchangeably? One is 223 L/MIN WATER, and the other is 368 L/MIN WATER. Also, regarding the safety valve, which value – the set pressure or the nominal pressure – is closer to the design pressure of the safety valve? What is the difference between these three?
The flow capacity of the two valves is different; the nominal pressure is related to the structural dimensions, while the set pressure is determined based on the process operating pressure.
In national standards, Set Pressure is translated as \"set pressure\" (it is also referred to as \"adjustable pressure\"). The definition of this term in the recommended standards GB/T12241-2005 or GB/T1242-2005 is similar to that in the European standard ISO 4216; however, it is rather vague and not practical for use. In the mandatory standard GB12241-89, set pressure is defined as the opening pressure. Generally, in accordance with the definition provided by ASME PTC-25, the set pressure of a regular safety valve – which in American standards includes three types of pressure relief valves: release valves, safety relief valves, and safety valves – serves as the opening pressure in gases or liquids, and as the popping pressure in steam media. I found this online. Can it be assumed that the design pressure is essentially the set pressure?