3 replies to this topic

[FMS]

Steam traps installed at 600# header send the condensate to 150# rating condensate header which is connected with De-aerator with adequate sized PSV.  If isolation valve on 150# condensate header (upstream of De-aerator) is closed inadvertantly, then the header might get pressurized as the traps are mostly leaking.  So I want to know that what releiving rate should be selected for installing a PSV on condensate header.  Is there any Engineerin Standard which gives guidelines for such a circuit.  Secondly, as a worst case this PSV should be sized on steam (leaking traps) or condensate?

[fallah]

FMS,

 

I don't think there would be a specific engineering standard for this matter... 

 

1-Relieving rate would be based on the trap leaking rate while there is maximum pressure in upstream and the pressure in trap downstream is equal to 1.1 times of the PSV set pressure.

 

2- The PSV should be sized for two phase (steam+condensate) flow.

[Bobby Strain]

If the isolation valve is manual, then no relief valve is required. Lock open the valve if necessary. Nobody is going to go around closing valves for no reason.

Bobby

[fallah]

Bobby,

 

Not all manual valves especially those are considered to be in closed/opened position frequently, can be equipped with LO/LC facility...

Edited by fallah, 27 April 2013 - 11:35 AM.