Double offset and concentric butterfly valves are usually soft seated containing some thermoplastic or elastomer seat. This results in temperature limitations and chemical compatibility concerns. However soft seated valves provide better seal performance. The triple offset valve design allows...
I am mistaken. I was looking at the coldworked condition. The mechanical of the annealed condition are identical. I still question why the deviation from the recommended rolled bar in API 600. Is the forged material superior in some way? More machinable, less likelihood of defects, etc.?
Understood, but reviewing the specification the A276 material seems to have a higher tensile and yield strength requirements which would make me think it would be a superior material for a stem. Am I missing something?
I have noticed that the bill of material for many API 603 valve manufactures specifies a ASTM A182 316 stem material. However in API 600 trim designations, the stainless trim stem material recommended is ASTM A276 316. I am curious why the deviation for API 603 valves? Is there some corrosion...
I am curious if anyone has any experience with NI hardened CF8M in amine service. I am aware that nitrided SS has decreased corrosion resistance but cant find any information on if it is still suitable for some services. Also if if NI hardened CF8M has begun to rust will it continue or is the...