Propane tank receiver

[normspanners]

I am not saying they do not explode but it is not very common, I dont think and I wouldnt want to be holding it if it did ------but. I had a brand new dunlop tyre blow over the outer rim on me at about 50 odd psi and that was interesting, compressed air does have some force though

 

[MattF]

Before I look at that, it isn't another shot of you semi naked, is it?

Regarding the explosions, I seem to recall some study being done on that point in America, and I'm almost certain the conclusion was that it was more likely due to oil combusting within the tank/system, for whatever reason, than being caused by tank deterioration. I could be mistaken however, as it was several years ago that I noted it.

 

[brightspark]

a rotten tank will pinhole and leak before anything more serious happens . a 1 gallon oil can can hold 50 psi before the crimped ends fly off

 

[Burdekin]

My job is to make sure oil and gas stays in the pipes and vessels. Never seen a pressure vessel or pipe explode, leak, yes unfortunately. A hole means a leak not a catastrophic explosion, welds failing due to corrosion or cracking are the biggest danger of a possible imediate release.

 

[Bill Edwards]

I too have only ever known corrosion causing leaks, never catastrophic failure. But I am well aware of the huge force that's unleashed if compressed air manages to blow something apart (tyres) and this is always in mind.

 

[Kent]

Yes very dangerous, but don’t understand how the propane contaminates the metal ??

Be interested to understand how this happens

I’ve made quite a few BBQs out of cylinders, no issues to date

The way I understand it is that's what happens. I have seen this with a far less flammable substance (dewaterering oil actually ) I don't know if you remember but there was a very big case in the press about a fella working on some road project a year or two back. They wanted him to cut up a drum that had been cleared of a fuel with a pressure washer but it was then left.
The injury was horrific one of those sort of things when you ask yourself - would I want to survive that?

 

[Kent]

Yes very dangerous, but don’t understand how the propane contaminates the metal ??

Be interested to understand how this happens

I’ve made quite a few BBQs out of cylinders, no issues to date

Come on you of all people know better than use done it before excuses

 

[brightspark]

all I can say is if u don't feel comfortable don't do it . bottles washed out and filled with water when welding are going nowhere

 

[Parm]

Come on you of all people know better than use done it before excuses

Yes I do know, I fact I have a very relevant case that I’m investigating

I never make excuses, there is a safe way to do it

 

[Parm]

all I can say is if u don't feel comfortable don't do it . bottles washed out and filled with water when welding are going nowhere

I agree, while I never advocate ditch H and S

You also need to have the confidence to do something off the track

 

[Parm]

No more shop talk from me today

 

[normspanners]

Fuel tanks can hold gases, but that is usually in the seams havnt heard of it impregnating the steel, it can plastic or rubber hose that is why you cant paint some motorcycle fuel tanks, well you can paint them, it just wont stay on and 'bubbles' in places, so I wouldnt want to weld a plastic tank but havnt got the right rods anyway!

A paper on the subject from MOD if it helps
https://assets.publishing.service.g...uploads/attachment_data/file/33546/spec31.pdf

 

[normspanners]

I remember a story and seeing a picture about works bmc mini rally team that the fuel tank bracket had broken and needed welding they didnt have the time to drain and clean so they filled it FULL on the premise that a full tank cant explode. coz there is no air to cause an explosion .Not something I would like to test on the side of the road but they did it ! in the same way that an intank motor doesnt explode even though the brushes etc is in the fuel. I have stripped several tanks that the wiring has literally burnt through and stopped the car the wires in free air above the fuel level so there must have been an almighty spark when that let go but nothing happened.

 

[Bsmith]

There were often new tapping stubs welded on 'live' gas vessels and pipework at an oil terminal that I worked on, safe enough as no air present in them. If I remember right, think it takes 1 part fuel and 11 parts oxygen for combustion/explosion to take place.

 

[daleyd]

There were often new tapping stubs welded on 'live' gas vessels and pipework at an oil terminal that I worked on, safe enough as no air present in them. If I remember right, think it takes 1 part fuel and 11 parts oxygen for combustion/explosion to take place.

It changes for different types of flammable gases, but there is a lower explosive limit (LEL) and upper explosive limit (UEL) sometimes referred to as upper lower flammable limits .

If there’s not enough flammable material present to reach the LEL then your ok, and equally if there’s too much (more than UEL), then it’s also “safe” (though I wouldn’t like to test this theory for myself!!)

In between these limits then that’s where the problems occur. I used to work with dryers that dried solvents and it was critical that we didn’t go near the LEL, we did this either through design (minimum flow rates for exhaust fans, plc’s that double checked flow rates etc) and/or by having an LEL monitor that sampled the air inside - if we got more than 25% of the LEL then the machine and process would shut down.

 

[Maker]

and equally if there’s too much (more than UEL), then it’s also “safe” (though I wouldn’t like to test this theory for myself!!)

Cody's lab proved this, yesterday in fact, by burning oxygen in a propane atmosphere.

 

[daleyd]

Cody's lab proved this, yesterday in fact, by burning oxygen in a propane atmosphere.

I’ve no reason to doubt it’s not true, I just wouldn’t want to try it myself!!

With a “lean” mix as long as you introduce no more flammable gas then your ok, with a “rich” mixture I imagine it could quite easily dilute without you knowing. Hats off to the guys that work on stuff where it has to be done this way