Api 6a Trim Material

[yalkamer]

I have been searching the web for locating the correct definitions of different trim material options defined by api6a but many different sources indicate something else. Is there anyone that can inform me about the accurate trim materials defined by api 6a?

I am trying to select a correct api 6a gate valve for 550F steam application.

Thanks in advanced

 

[yalkamer]

One further question, does anyone know what kind of classification is T3 geothermal trim selection?

 

[texag]

yalkamer

API 6A material classes are broken up in to two basic groups; general service and sour service. A sour service environment contains H2S. The 6A specification defers further definition of sour service to NACE MR0175.

Do you have exposure to H2S or will there be free Hydrogen?

 

[yalkamer]

I am not sure. The valves will be used for wellhead of geothermal wells. If you can advise for both cases that would be highly appreciated. Regards

 

[texag]

Given the termperature you listed, the valve would fall into the "Y" temperature class of API 6A, which is 0F-650F.

I am not too familiar with geothermal wells but aren't those closed loop systems where you are simply exchanging heat with the large heat sink that is earth? Therefore, you should not have exposure, at the surface anyway, to H2S gas.

You may run into H2S when drilling the well.