Page 1 of 1
Acetylene tank valve removal?
Posted: Tue Oct 25, 2011 8:51 am
by jmez1996
I got an empty 16oz acetylene gas bottle to use as a air chamber on my next gun but it has an internal valve in the stem which stops the gas escaping when there is no fitting on the bottle which i need to remove.
Anybody got any ideas how this can be done?
Can it be drilled out safely?
cheers
Posted: Tue Oct 25, 2011 8:54 am
by Alster370
I would feel safer punching the valve though, its what I did with my paintball tank. Just make sure you can get it out though, or else you are doomed to incessant rattling every time you move the tank.
Then drill the stem afterwards so that the cavity you are left with is big enough for the valve core to drop out of.
Posted: Tue Oct 25, 2011 9:38 am
by jmez1996
Alster370 wrote:I would feel safer punching the valve though, its what I did with my paintball tank. Just make sure you can get it out though, or else you are doomed to incessant rattling every time you move the tank.
Then drill the stem afterwards so that the cavity you are left with is big enough for the valve core to drop out of.
thanks! pretty much exactly what i needed to know
cheers
Posted: Tue Oct 25, 2011 9:48 am
by Gun Freak
Can you just unthread the whole valve? You may be able to find a fitting with similar threads.
Posted: Tue Oct 25, 2011 11:30 am
by wyz2285
do you mean a pin valve? the valve core can be taking out easily, but you have to remove the whole valve first
Posted: Tue Oct 25, 2011 12:20 pm
by Technician1002
Acetylene gas is dissolved in acetone. The Acetone is kept in a filter type material. The empty tank is not empty. In old tanks the filler was asbestos.
Acetylene is unstable when compressed to over ~30PSI. This is why it is dissolved instead of just compressed.
http://en.wikipedia.org/wiki/Acetylene
Acetylene is not especially toxic but when generated from calcium carbide it can contain toxic impurities such as traces of phosphine and arsine. It is also highly flammable (hence its use in welding). Its singular hazard is associated with its intrinsic instability, especially when it is pressurized. Samples of concentrated or pure acetylene can easily react in an addition-type reaction to form a number of products, typically benzene and/or vinylacetylene. This reaction is exothermic. Consequently, acetylene can explode with extreme violence if the pressure of the gas exceeds about 200 kPa (29 psi) as a gas[16] or when in liquid or solid form. It is therefore shipped and stored dissolved in acetone or dimethylformamide (DMF), contained in a metal cylinder with a porous filling (Agamassan), which renders it safe to transport and use, given proper handling.
Posted: Wed Oct 26, 2011 2:38 am
by jmez1996
Technician1002 wrote:Acetylene gas is dissolved in acetone. The Acetone is kept in a filter type material. The empty tank is not empty.
So is it safe to remove the valve inside? and use as an air tank?
Posted: Wed Oct 26, 2011 4:52 pm
by ramses
jmez1996 wrote:Technician1002 wrote:Acetylene gas is dissolved in acetone. The Acetone is kept in a filter type material. The empty tank is not empty.
So is it safe to remove the valve inside? and use as an air tank?
Probably not. It's made for about 30 PSI, but may be thicker than necessary for durability.
Posted: Wed Oct 26, 2011 5:00 pm
by Zeus
Not to mention the structure inside will restrict flow, or may exit the tank and lodge in the valve.
I'd dissolve NH<sub>4</sub>NO<sub>3</sub> in the tank and let it deposit throughout the tank, then use it for storing dry ammonia.
Also, I believe some tanks store acetylene at 150PSI, it being dissolved reduces the chance of it detonating<sup>1</sup>
<sup>1</sup> It does detonate, as opposed to burning.
Posted: Wed Oct 26, 2011 6:53 pm
by Technician1002
The tanks run about 125~160 PSI to the regulator. This is why it is important to use flashback arresters on the torch and use low gas pressure. I rarely use over 5 PSI with my torch.
