The issue between the nominal pressure of the pipe and the maximum allowable pressure of the fittings (common problem)
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Direct example: The design pressure of the steam pipeline is 1.1 MPa, and the design temperature is 200℃； The nominal pressure was originally set at PN16 ； The maximum allowable operating pressure for steel pipe flanges (20#) at 200°C is 12.6 MPa ； At room temperature, it is 14.7 MPa. According to the specifications, the hydrostatic test pressure is 1.74 MPa, which exceeds the maximum allowable operating pressure for steel pipe flanges! Are flange connections on the steam piping really okay? Some people say it’s possible, but where is the basis for that? HCBBS has had similar posts, but it seems no consensus was reached! Do not water!
Generally, the allowable stress for the materials we use is 0.6 times the material’s minimum yield strength, which is considered quite safe; the value of 1.5 times the design pressure for hydrostatic testing comes from this principle.
No problem, the nominal pressure margin is quite large
Your requirement is just normal low-pressure steam; there’s no problem with that, right? ? ? ? ?
Did the original poster make a mistake in writing? It's 1.26 MPa and 1.47 MPa, right?
I also think he wrote it wrong. MPa and bar are being used interchangeably, right?