Re: Re: Reinforcement Pad Weep hole

From: <Christopher>
Date: Tue Sep 13 2005 - 12:47:00 EDT

On Sep 13, 2005, at 11:17 AM, Tony Paulin wrote:

> When we've seen this happen, the weld was started one day, and finished
> another, allowing water to collect in the pad/vessel space. Evaporating
> water during PWHT caused bulging.

Again--how do you know that the distortion wasn't caused by the welding heat? Are you telling me that any steam or hot air couldn't get out the same way the water got in? Anyone ever done a couple of simple calculations on the pressure it'd take to bulge a doubler? And whether the water would even evaporate at such a pressure? And what would happen to the pressure 10 minutes later when the weld cooled down?

And whoever started a weld on a wet surface? That's a good way to get a hydrogen embrittled weld.

Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=WP3dBxiNnSs7FgaKHrIxkj0Ju51GzYUSKX3Dmp5LxhkMf5_k5EY_JkhQp74mM3-HPpkv0bn2vNAvaIISBIw">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 Tue Sep 13 12:47:00 2005