NYC steam line rupture

From: <Christopher>
Date: Sat Jul 21 2007 - 12:13:00 EDT

I'm surprised there's been so little comment about the pipe that ruptured in New York. Does everyone realize what happened and that it's serious damn business?

Anyway one thing puzzles me. The cause of the rupture has been postulated as 'condensate hammer'--condensate slammed around which overloads the pipe. That's the first time I've ever run into, and I don't understand it. Supposedly the line runs at about 200 psi. The only way you can have any significant amount of condensate is if the steam is saturated--at a temperature of about 381F. If it cools even a little you get condensation and if the temperature goes up even a little the condensate flashes to steam. It's not apparent to me that you can have condensate and steam in the same line for any appreciable time. Can anyone explain how this happens?

OTOH, given that the line is about 80 years old, it seems a lot more likely that corrosion or settlement is the cause.

Christopher Wright P.E. |"They couldn't hit an elephant at <a href="/group/PipingDesign/post?postID=u1O1rckIs7d3o2uTJLI3GFdyBHygUcVcXo1jpopbSc6if2trLQlU0QvMVMK2tVVosmYlz7386LDNw0k">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 Sat Jul 21 12:13:00 2007