2 replies to this topic

[jawa]

Dear All,

I am in a situation to confirm the Design Temperature downstream choke valve in a well head platform. The maximum temperature upstream choke is 110 degC.

Please advise a procedure/concept to establish this Design condition.

This wellhead platform exports 120 mmscfd of gas through a sealine and the pipeline group requires me to confirm the design temperature at export conditions.

While performing the steady state analysis of this export pipeline on Pipephase it was assumed the gas is at 120 degC. Please advise if design or operating temperature should be used for these Steady state simulations.

Your prompt advise will be much appreciated.

Regards,

Jawa

[JoeWong]

Jawa,

Establish a maximum operating temperature downstream of the choke throughout the production life. Maximum Design temperature would be the maximum temperature plus a design margin.

As mentioned, it is a wellhead platform. Do you heat the gas before export ? The choke upstream temperature is only 110 degC, so why do you need to consider 120 degC on the export end ?

For a pipeline, I would think the maximum operating temperature would be considered.

[jawa]

Joe,

Thanks for your prompt reply.

Designing on a conservative basis and comparing with previous design it was decided the Design Temperature downstream of choke shall be 125 degC. However, the pipeline group went ahead with a Design Temperature of 120 degC for the export pipeline as they did not want to redesign the pipeline as many manhours were already spent.

As a Process engineer, I realize that this situation is acceptable, as long as the client would not disapprove, and basically a difference of 5 degC may not impact the design of pipeline to a large extent.

Please share your opinion.

Regards

Jawa