Torque of K-Valves...
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As tight as you can get it by hand.
R
redacted
Guest
At working pressures, you won't move that valve. Drain the tank and valve removal might require a light tap from a rubber mallet. Lub the O-ring before you assemble.
The 0-ring provides the seal and the presure holds it tight. I think a more accurate answer would be to tighten it to a torque of one grunt. I use a wrench but choke way up on it and give it about a grunts worth.
The Chairman
Chairman of the Board
Please check the manufacturer of your particular tank for torque specifications. That is always wise...
1) USE A WRENCH! There is very, very little supporting the valve stem... it is NOT supported by it's threads as it would seem to be. If you have ever taken a valve apart, you will realise that the valving mechanism is in two parts... the part that screws in and out, and the stem that merely turns it. You can ruin it easily if you "tap" on the handle. DON'T DO IT!
2) Most static O-rings require a preload for them to withstand 3000 psi and more. If you look at your tank, you will find that the O-ring groove has been fly cut, or recessed into the tank. The O-ring will not extrude IF the valve body is flush with the upper portion of the neck. Using a wrench and a few whacks ON THE WRENCH will seat the o-ring properly in most cases.
3) DO NOT LUBE THE O-RING!!! It is static and does not need to slip. That being said, put a little of Dow Corning's lube (for air) or Krysto-Lube (for NitrOx) on the THREADS of the K-Valve to keep the chromed steel from galling the aluminum over time. BTW, you DO have to lube the #10 O-ring that seals the valve stem if you choose to rebuild it. It is dynamic, and should be replaced yearly as well.
4) Did I mention that you should find your manufacturer's torque specs???
Tanks are simple; Use the Right Tool (URT) and you will not damage your equipment. Take short cuts and you could lose air at depth... Don't let your desire to play things fast and loose compromise your safety.
1) USE A WRENCH! There is very, very little supporting the valve stem... it is NOT supported by it's threads as it would seem to be. If you have ever taken a valve apart, you will realise that the valving mechanism is in two parts... the part that screws in and out, and the stem that merely turns it. You can ruin it easily if you "tap" on the handle. DON'T DO IT!
2) Most static O-rings require a preload for them to withstand 3000 psi and more. If you look at your tank, you will find that the O-ring groove has been fly cut, or recessed into the tank. The O-ring will not extrude IF the valve body is flush with the upper portion of the neck. Using a wrench and a few whacks ON THE WRENCH will seat the o-ring properly in most cases.
3) DO NOT LUBE THE O-RING!!! It is static and does not need to slip. That being said, put a little of Dow Corning's lube (for air) or Krysto-Lube (for NitrOx) on the THREADS of the K-Valve to keep the chromed steel from galling the aluminum over time. BTW, you DO have to lube the #10 O-ring that seals the valve stem if you choose to rebuild it. It is dynamic, and should be replaced yearly as well.
4) Did I mention that you should find your manufacturer's torque specs???
Tanks are simple; Use the Right Tool (URT) and you will not damage your equipment. Take short cuts and you could lose air at depth... Don't let your desire to play things fast and loose compromise your safety.
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