Purging butane cylinders

[guest27]

I have a couple of non-standard butane cylinders that I think I will struggle to swap for Calor ones, not to worry I want to use one as a res for a vacuum pump.

Does the valve just thread into thte top?  how do I purge the residual gas - water. carbon monoxiode or just throw a match at it.. he he he

Any ideas on the thread form if it is threaded

Any thoughts on a manual valve for it ?

Thanks

R

[Richard]

I just fill them with water, to the brim, and drain them off.  Then I attak them with angle grinders.

[guest27]

Perfect - thanks.

R

[johnr]

youd be better purging with nitrogen than using water. theres no way of removing the residual water from the inside of the tank and then vac it out. (steel tank?)

[guest27]

Yup - steel tanks.

No nitrogen - cept in the atmosphere but I have a source of air with all  the oxygen removed - car exhaust.  Mind if the water proves to be a problem I guess I can put the tank on the bonfire for a bit - having purged it and removed the top....

R

[guest18]

Drop in some dessicant bags? iirc you find them in new trainers, could maybe blag some free from a shoe shop if you pass one?
edited to add, I mean for getting rid of the water not the gas!!

[Jez F]

As Butane and Propane are both heavier than air, why not remove the valve( make sure it's empty first!!) and stand it upside down, a few inches off the ground outside for a couple of days, should save messing around with water and having to dry it out.
 Jez