Ball valve qualification test for vacuum service

Does any one know of any qualification tests as required by a standard for ball valves designed to full vacuum.

The standard API and EN valve standards does not address it.

There used to be a Shell SPE addressing this. But it is now not listed in the current version.

I found these threads at eng-tips,
http://www.eng-tips.com/viewthread.cfm?qid=93211&page=9 http://www.eng-tips.com/viewthread.cfm?qid=150132

Sajit Received on Thu Feb 07 22:55:00 2008