Tank valve lubrication

[Volcano Divers]

Hi,

I recently brought my tanks away to get hydrostatic tested. As far as I know we only have one option here in Nicaragua which is not a company specialized in Scuba cylinders. When I got the cylinders back and opened them, I noticed they smeared some grey lubrication substance all over the valve. I read that it does not need any lubrication, I was just wondering if this would be ok. The company is hard to reach over the phone/e-mail and I would like to save myself a 3 hour drive there.

Will it be more difficult to take the valve off in the future?

Greetings Theo

 

[Scared Silly]

They probably (hopefully) used a silicon based lubricant which helps with preventing galvanic action between the cylinder and valve. Assuming the cylinder is for air only there should be nothing to worry about. Though I would probably try to find out what lubricant was used just to make sure it is compatible with breathing gas.

 

[2airishuman]

Depends what it is.

If it's pipe dope, it shouldn't be there. Pipe dope is used to seal tapered threads that do not utilize an o-ring, and is essentially a mixture of clay and oil, usually resulting in an opaque grey, white, or yellow appearance. It is not so much a lubricant as an inert compound that fills gaps where the threads do not contact each other. Tapered threads are still widely used on industrial gas cylinders, but were phased out for SCUBA cylinders by about 1970.

The straight threads now used on SCUBA are supposed to be lightly lubricated before assembly to prevent galling. I use Tribolube, but other lubricants can be used as long as the cylinders will only be used with air. Tribolube is transparent white.

 

[DEdiveguy1]

I would probably try to find out what lubricant was used just to make sure it is compatible with breathing gas.

Good advice you should follow!