Sachin,
The by-pass has reasons that the valve (trap) will never understand.
In case the steam trap fails, the by-pass can (with all its considerations) be used has a manual trap or if left partially open (bleeding) has a semi trap. The problem is not how long it takes to replace the fault trap, the problem is how long it takes to start doing the replacement and having a waste in steam mean while.
Steam is a hard fluid to handle, there fore, the trap will fail. (Specially if you do not install the by-pass).
Regards, Arturo Murillo
Tuberias Visa , México
sachin.pawar@fluor.com wrote:
> In process of PID updation, Process Dept. deleted the By pass line along
> with block valve.
> I went through search engine & found that there are steam traps designed
> to work 3 in 1 (Trap, Bypass line and stop valve, 3 functions in one unit)
>
> Probably it may be one of reason. I am interested to know more possible
> reasons.
The bypass for a steam trap only exists so that the trap can be replaced in case it malfunctions while the plant is still in operation. I suppose the thinking is that the trap can be isolated and the bypass valve can be cracked open until the trap can be replaced. This will waste steam.
Almost all facilities will have replacement traps in stock, so the real issue is how much steam condensate will build up upstream before the malfunction is noticed or during the time it takes to replace the faulty trap. In my opinion, the bypass is unnecessary but you still need up and downstream block valves for changeout.
I'm no steam system or operations expert though, maybe someone else can correct me or add more info.
Paul
[Non-text portions of this message have been removed] Received on Thu Oct 18 11:26:00 2007
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