Re: Flange Grades

From: <Christopher>
Date: Fri Sep 09 2005 - 15:06:00 EDT

On Sep 9, 2005, at 1:06 PM, Brighton Yuhoo wrote:

> 1- If a pipe and a flang to be welded to-gether, should they have
> close grade (Tensile Strength)? Is it because equal thicknesses?
Equal thicknesses help, but weld compatibility is the main driver. No point welding a stainless or Cr-Mo flange to a carbon steel pipe. The welding is a nuisance and you don't gain anything.

> 2- Which material group do Falnge WN A694 Gr.f65 & Gr.f70 belong to?
> Does F65 denote tensile strength of 65 ksi for this flange?
You should check your own set of specifications or the piping code for specification particulars. A-694 covers a lot of stuff. Your guess probably right, but the UTS may vary with thickness or processing variables.

> 3- Can pipe API 5L Gr.X70 be welded to Flange WN A350 Gr.LF6?
Sure, provided you have a qualified weld procedure and welders who are qualified to use it. I'm not finding Gr LF6 in my (old) Section II listing but it's probably an alloy steel, so a proper weld procedure is a must.

Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=NNJ7Y96qRTIH15dU33Dqk9dMpbOZPzOzmLnjhzB4zPsKCFHt1QotCRLaJO1RmdH4zgQhO9Nj-JvuXQ">chrisw@skypoint.com</a> | this distance" (last words of Gen.

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

1864)
<a href="http://www.skypoint.com/~chrisw/">http://www.skypoint.com/~chrisw/</a> Received on Fri Sep 09 15:06:00 2005