what is the difference between API 6D and API 600

[Vinzzzz]

hi

a direct question, what is the difference between API 6D and API 600 for gate valves?

It is possible, that the only difference is due to the fact that API 6D shall be referred only to Pipeline Valves?
If the response is negative, is it possible that one code is more restrictive than the other and the valves costs become higher?

thanks in advance

Regards Vinz

 

[reverman]

API 6D does have some different design requirements I believe the port diameters are different, and the required pressure testing is quite different. API 6D is not limited to Gate valves, API 600 is only bolted bonnet steel gate valves.

API 6D is preferred for upstream pipeline valves. API 600 is written more in mind of downstream piping.

to produce API 6D valves the manufacture needs to have the API 6D monogram. API 600 also has a monogram program but it's still optional and most manufactures have not done it yet. This is a bit of a sore subject at API meetings now. API is pushing the monogram program forward for API 594, 600, 602, and 603. The manufactures are resisting since it seems to just be a API money grab and the end users are not demanding it yet.

 

[reverman]

API 6D is also only parallel slide gate valves and it requires bonnet venting for certain services