Hi Jason,
That sounds like a really tricky problem you have there. I would think you might be better heading over to the Materials Engineering forum with this question (Metal and Metallurgy section. As well as talking to a local Materials Engineer. They might be able to advise if the material...
Hi AP
I have had to make a couple of assumptions here, however I will do my best to try and assist.
You are correct (as far as I can see) that there is no listing in API600 for "Extended Body Design" valves, nor is there any listing for them in the referenced specification for end to end...