soldering ball valve worry

Royboy

is what powers my torch. I'm guessing that not many of you guys use that, but its worked OK for me and I do 98% of my work with 1/2" & 3/4" tube. probably ought to give mapp a try one of these days, though. ;<)

Royboy

I've always had this nagging spooky sense

when soldering ball valves in particular, of the potential of some sort of explosion from pressure building up in the valve mechanism. nothing's ever happened but I often get this little voice-in-the-ear sort of awareness that there is danger ...

today I was building up a manifold using a bunch of 1/2" Hammond ball valves - which I have recently switched to. I generally solder with valves open and part way down the line I heard a distinct pop as I was soldering one. nothing visible. I kept going and a couple vlaves later there was a similar and much louder pop, and the pex adapter that I was sweating into the top of the valve flew up about a foot in the air. I jumped! looking down into the now-exposed valve passage I saw a loop of the seal around the ball protruding into the flow-passage. after it cooled, I closed the valve and it seemed to pop back into its proper configuration.

so ... from this experience I am thinking that perhaps it's better to solder ball valves half open, so the cavity around the ball is open to atmosphere. wondering if this is a standard practice that I wasn't aware of (one the hazards of being a one-man self-taught operation) - and also intrigued that I've soldered hundreds/thousands of ball valves without this happening, but today twice ...

go figure - Roy

lchmb

I was

I was taught to alway's solder with the ball valve half open/closed. Never had a problem doing it so I guess I'll stick with it...

Rich Kontny_5

I learned from..

One of the best mechanics I ever have worked with to leave the ball valves about half way open instead of all the way open.If you think about it, it makes great sense because moisture can be trapped in the void between the valve housing and ball. This moisture depending on the make or style can be enough to become superheated to create enough steam pressure to rupture the valve's side wall.

In other words leave the handle in between parallel and perpendicular. You sholud not have any further problems.

Rich K.

Royboy

yeah ... that's kind of what I had concluded

and despite that persistant nagging worry, had never thought about the valve construction enough to realize why it was a good concern. half open henceforth.

hr

another thing about ball valves

once they have had water in them, and you turn them to the off position to solder, or un-solder... If you get them too hot the water in the ball expands, or turns to steam and pops the seals out. Usually they are done after that pop. Never to shut off completely again.

1/2 and 1/2 is the safest position, unless you have a very low temperature solder.

The thin walled brass ball valves don't take much heat to solder. Not like the cast brass versions, anyways.

hot rod

To Learn More About This Professional, Click Here to Visit Their Ad in "Find A Professional"

Lyle C

1/2 & 1/2

Don,t forget when you winterize a system the same is true. I have seen a lot of cracked ball valves on very costly RPZ's.

Cosmo_3

been lucky so far

As far as soldering, many times I have soldered one side of a ball valve while holding back public water supply pressure in service situations, it is actually common practice when using a jet-swet.

Proper soldering techniques I am sure prevents blowing out seals most of the time I think, as well as tighter machining like HR says.

Never, never, never underestimate the power of steam....



Just a question, do you use air-acetylene or propane/mapp?

Maybe the tighter flame characteristics of air-acetylene torch tips contribute to less over heating by keeping the heat where it is needed instead of all over like a dog lickin' your face!!!!


Cosmo

MIke_Jonas

you could always....

use ProPress. No flux no solder no gas no problems!!