5 replies to this topic

[roshimessi]

Dears i want to know what is the hot bypass line in compressor. when is it use?

is it surge line?

it use for all type of compressor or not?

(Centrifugal and reciprocate)

 

thanks in advance

[Art Montemayor]

Please be specific when describing your query.  Our members need as much detailed information as possible in order to respond with the correct and accurate answer.

If you are referring to an air conditioning system, then:

 

Hot gas external bypass is recommended when the load on a refrigeration evaporator varies and the operation of an air conditioning system is desired at lower than design conditions.  Additionally, hot gas bypass is used when the evaporator coil is designed for comfort cooling (latent and sensible loads) versus precision cooling (all sensible loading).  If return air conditions will be 72 °F / 50% RH or lower, the unit should incorporate the hot gas bypass option.

 

Hot gas bypass provides an artificial load on the evaporator by introducing a portion of high pressure, high temperature compressor discharge gas to the evaporator / suction side of the system.

 

[roshimessi]

Dear art

thanks for your reply

in the plant operator told me that for start up of the reciprocate  compressor or in shut down case we open hot bypass line this line is from

discharge line of the compressor to suction line. it use  for equalizing .

i think the function of this line is like surge line in centrifiugal compressor.

 

thanks alot

[Bobby Strain]

Actually, the line is open only for starting, and must be closed immediately. Usually this valve control is incorporated in the compressor load controller. It's typically used on centrifugal compressors as well; not for surge control, but for starting.

 

Bobby

[fallah]

Hi,

 

The discussions in below link of this site can help you out to understand the hot gas by pass valve/line in the compressors:

 

 

http://www.cheresour...s-bypass-valve/

[sanchit_11]

Dear Roshimessi,

 

If your question is with respect to Centrifugal Process Gas Compressor then answer is as follows:

 

Hot gas bypass line in centrifugal process gas compressors are provided with sole intent of preventing hydrate formation at downstream of Anti-surge/Recycle valve which can occur due to large pressure difference between upstream and downstream pressure across Anti-Surge or Recycle valve.

 

The anti-surge/recycle lines are tapped from downstream of compressor discharge gas cooler and carry cold gas through them. In view of the same hot gas bypass line is tapped from upstream of compressor discharge gas cooler and connected to upstream of  Anti-surge / Recycle Valve. It serve to increase temperature of cold recycle gas by certain degrees to prevent hydrate formation.

 

Hot gas bypass lines are of much smaller in size in comparison to main recycle line and usually have RO for restriction of flow.

 

I hope this answered you query.

 

regards

Sanchit