View Full Version : solder joint failure?

11-24-2008, 09:36 AM
Hi all,
I have done a fair amount of plumbing at home, my question is about a brass gate valve i installed to replace an old frozen (from hard water build up) one. I cleaned the pipe after removal with fine sandpaper, but got distracted and never cleaned the brass valve. I used plenty of flux on both sides, sweated them together, and have no drips. I am just worried that the joint is weak and the valve might come off, anyone ever see this? No one is home for 8 hours so a failure would be horrific. I have to believe a valve will drip first before failing so catastrophically, right now i turn the water off when i leave the house.

Can I reheat the valve and maybe rotate it 360 degrees and let it cool? I am sure if i remove it I will not be able to clean it to get it back on. appreciate any feedback.

sleepless in NJ

11-24-2008, 09:41 AM
Unless the valve's socket was very dirty or oxidized, it was probably as clean as if you had prepared it. If that is the case, don't worry about it. In any case, just reheating it and rotating it would not make a better joint than you have now. Worse case, if you do remove it you should not have any problem cleaning it and reinstalling it, assuming you do not overheat it and damage the internal seals.

11-25-2008, 11:28 AM
You are probably OK. But you would never know unless you ultrasonically tested the joint ( non destructive test) or cut the joint lengthwise ( destructive test)

In 1963, after the loss of the submarine Thresher ( SSN-593) the Navy went back and started inspecting silverbraze joints in stainless steel and monel sea water pipes. Found many instances of WAY to little penetration of the filler. Good enough to pass pressure test, but add a little vibration, etc, and pretty soon you have water in the people tank, which is a VERY BAD THING!

ALL piping on all submarine was redone WELDED. Boats had their operating depth restricted by half until the retrofits were done.l

Joe the Plumber
11-25-2008, 01:05 PM
Like hj, I've never recleaned an already clean brass valve for soldering.
I pull em out of the wrapper, flux em and solder em.

This isn't silverbrazing joints in stainless steel and monel sea water pipes.
It's jus solderein' with Lead Free residential copper tubin'.

Soldered with No-Lead Solder