6 replies to this topic

[RUBABU]

Wish to know about the recommended bypass piping configuration for a Fuel Gas Scrubber please. Choices are

1. bypass line with isolation valve

2. bypass line with isolation valve and spectacle blind upstream & downstream of isolation valve

3. bypass line with double isolation valve with one spectacle blind in between 

[fallah]

RUBABU,

 

It depends on the maximum upstream pressure, the safety issue(s) of fuel leakage to downstream, bypass line main function,...

[RUBABU]

a. Maximum upstream pressure is 180 psig.

b. no safety issue of FG leakage to downstream since downstream facilities consist of FG manifold for distributing FG to consumers. i.e. it is okay if bypass valve leaks (valve passing)

c. bypass line main function is to release the vessel for maintenance and to operate the vessel in bypass mode for a short period.

[fallah]

a. Maximum upstream pressure is 180 psig.

b. no safety issue of FG leakage to downstream since downstream facilities consist of FG manifold for distributing FG to consumers. i.e. it is okay if bypass valve leaks (valve passing)

c. bypass line main function is to release the vessel for maintenance and to operate the vessel in bypass mode for a short period.

 

RUBABU,

 

Then, I think a bypass line with an isolation valve and a spectacle blind at its downstream would be adequate...
 

[RUBABU]

In that case the downstream spectacle blind would be used only for positive isolation of downstream section. i.e. the downstream section need to be shutdown to change position of spectacle blind from normal 'Blind Out' position to 'Blind In' position. right?

[fallah]

In that case the downstream spectacle blind would be used only for positive isolation of downstream section. i.e. the downstream section need to be shutdown to change position of spectacle blind from normal 'Blind Out' position to 'Blind In' position. right?

 

Yes, that's right...

[RUBABU]

Thanks for the feedback Sir.