Cracked Control Valve

[BAS_man]

Hi I am new to the forum, I friend recommend me to post this question here. I just installed some control valves in a chilled water system, 44 Deg F, no Glycol and some are leaking, and I found this problem. Has anybody seen this before? Could it be that I over used the Teflon tape?
Thanks a lot for your help.

[GA FRANK]

My guess would be that these are imports.China possibly.

[flange]

overtightened. a properly made connection should be hand tight in two to three turns, and require around another half turn to seat. this appears to be driven home using a wrench that was too big. threads are tapered, the more you push them in, the more the fitting expands, it cracks when it has had enough.

[mallron]

What flange said. That valve looks like it's almost fully seated on that union even though there's a nipple in-between.

[Octopus]

overtightened. a properly made connection should be hand tight in two to three turns, and require around another half turn to seat. this appears to be driven home using a wrench that was too big. threads are tapered, the more you push them in, the more the fitting expands, it cracks when it has had enough.

Flange is correct.

You could have a bad thread on your pipe or in the casting of that valve if you didn't over tighten.

[BKS60]

I have had a rash of valves cracking on an islolated location recently. All have been on hot water valves and when I started diagnosing the problem I found the PRV on the system was 100# on a two story building and the secondary pumps bumping another 20#.

I will be replacing the PRV next week and will see if the valve failures stop.

[manny238]

Belimo Valve??? Looks like its over tighten...Ive done this many times with a 24" pipe wrench.

[Control Man]

In the original posting the valves were over tightened , see that a lot with muscle bound plumbers / fitters and not just valves but TEES , unions ecte.

BKS60 what type of valves are cracking on your job ? , 120# is not that severe for bronze body valve.

[BKS60]

Delta control Products. None have seemed to be what I would call extremely tight and they have O-ring seats but they all are cracking at the thread section of the valve.

Maybe a bad batch who knows! They are all about 6 years old.

[BAS_man]

Thanks a lot guys!!! flange described it very well I think I overdrove it.