2 replies to this topic

[manuelh]

Good morning.

I have a cleaver brooks CB-600-600-150 st 600 HP

For procuce saturated steam

 

Design pressure:10.5 kg/cm2(149.34 psi)

Safety operation pressure: 9.5 kg/cm2(135psi)

Safety valves adjust:10.5 kg/cm2(149.34 psi)

 

What is the typical pressure for the boiler? Te safety operation pressure or typical is less?

Thanks

 

Manuel

 

[Saml]

What code is the boiler built to? ASME I?

 

If that is the case, you don't have names like "Safety Operation Pressure". You have Maximum Allowable Working Pressure (or some call it Design Pressure). You can operate as close as you want  to this value depending your risk tolerance for spurious pressure relief valves actuation.

 

10% margin is generally accepted as "safe" from the point of view of avoiding spurious relief events. But this is also dictated by:

 

- How confident you are about the valves calibration.

- How frequently you calibrate/maintain them.

- How stable your operation is. If the boiler is working at a very steady regime, you may get closer to the MAWP. If the seam demand is fluctuates in short term spans, 10% may not be sufficient.

.- The consequences of an spurious event. 

[manuelh]

Good afternoon Saml. Is ASME, you are right. I tried to explain better the term but only confuse. It´s maximum allowable working pressure(135 psi) and design pressure(149.34psi)

 

Thanks

Manuel