Re: [PipingDesign] Flange Material

On Oct 9, 2008, at 11:36 AM, <alimalvi300@hotmail.com> <alimalvi300@hotmail.com> wrote:

> I want to ask about flange material. We have received piping
> material spec. in which flange material is specified as "size
> range 24 inch and larger, Material A36, FF SO ASME CL 150. But as
> per ASTM A36 this material is for structural plate and also
> required impact test. I want to know can we use A36 material for
> large diameter flat face flanges used for cooling water.
Sounds like you didn't believe me the first time I told you this--it hasn't changed. The ASME Code Section VIII requires that flanges be forged or made from bar (including bar cut from plate) rolled and butt welded with the plate rolling direction oriented circumferentially. The butt weld must have complete joint penetration. You can't use rings cut from plate.

So, yes, you can use A-36 for flanges but only if you fabricate the ring as stated. You'll also have to run calculations to show the A-36 meets the requirements of Appendix 2 of Section VIII. It's far more practical to use forged flanges

Christopher Wright P.E. |"They couldn't hit an elephant at chrisw@skypoint.com | this distance" (last words of Gen.

.......................................| John Sedgwick, Spotsylvania