Screwdriver
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Ah. I see so you are telling me it didn't happen?
I am telling you it did. One of us is wrong and it isn't me.
- Thread starter LeviPrince123
- Start date
Ah. I see so you are telling me it didn't happen?
I am telling you it did. One of us is wrong and it isn't me.
Kayos
Gone......
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Send me a picture, I'm heading to a gas training centre next week and I'm sure they would love to see how you defied the laws of both physics and chemistry. I sure would
Screwdriver
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I am searching now but I know for sure I don't have a picture of the actual slush.
I inverted a Calor gas bottle with a screwdriver jammed in the valve and left it to empty. It formed a puddle underneath on the cold concrete "paddock" area outside my shed. The puddle had an island mound of white slush which I assumed was frozen propane. I threw a match on it to test the theory and it went off in a giant ball of flame.
That is my sworn statement of events, the rest of the "story" is me attempting to understand what happened. The link above suggests that propane gas can form a crystalline hydrate at "considerably above" the freezing point of water. You might want to investigate that before casting aspersions. It might also add a bit of spice to your gas training. Forewarned is forearmed and unless your training course covers propane hydrate, you might end up looking somewhat better informed.
I posted a link above. Well worth flicking though before you automatically assume I am wrong or lying about what I saw.
maz0
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The FIL likes to cut them up with the airhose method. He did explain a time though when he was plasma cutting a cylinder and it made a bang like someone hit it with a sledge hammer and gave him a squeeky bum moment. Some things which may have contributed... He vented and filled with water then drained, forgot about it leaving it outside for a few days, when he did cut it open he found the inside had a decent rust coating which may be the “pockets” that the liquid soaks into. Hes got no reason to tell fibs, hes far from a safety nanny and has cut loads up so I do believe him.
If you follow the advice on here so far you will be fine though.
If you follow the advice on here so far you will be fine though.
Pete.
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I think that seamed containers pose more of a risk than welded ones. They also tend to be higher volume so more capacity for an explosive mixture.
The number of things I have welded or oxy-fuel cut that were apparently 'clean' but issued forth a large volume of smoke says that it's quite possible to have enough residual stuff inside a drum even after 'cleaning' to form an explosive mix. The 'heavier' the content i.e. oil versus fuel or LPG, the higher the risk of non-evaporated fuel.
It takes very little gas to make a rather large bang as I have found out several times in my youth. It also takes not much liquid to make quite a lot of gas. You just have to pick your fights carefully.
The number of things I have welded or oxy-fuel cut that were apparently 'clean' but issued forth a large volume of smoke says that it's quite possible to have enough residual stuff inside a drum even after 'cleaning' to form an explosive mix. The 'heavier' the content i.e. oil versus fuel or LPG, the higher the risk of non-evaporated fuel.
It takes very little gas to make a rather large bang as I have found out several times in my youth. It also takes not much liquid to make quite a lot of gas. You just have to pick your fights carefully.
daleyd
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I would think leaving a cylinder open at ambient temperature for any length of time (ie overnight) would see any hydrates evaporate away, as it’s no longer under pressure and the boiling point of it would be well below zero. My understanding is that it’s the pressure which causes the hydrates to form and a vented cylinder at ambient wouldn’t allow them to remain for long 
. I would think this followed by a good purge with water or air would get rid of the majority.
Although I’m a complete ignoramus when it comes to this I did write some software for an oil platform when they were extracting high pressure gas from an oil well cap, and the temperature and pressure were part of the safety checks - of either were likely to cause hydrates a heating solution was routed through the valve train.
. I would think this followed by a good purge with water or air would get rid of the majority. Although I’m a complete ignoramus when it comes to this I did write some software for an oil platform when they were extracting high pressure gas from an oil well cap, and the temperature and pressure were part of the safety checks - of either were likely to cause hydrates a heating solution was routed through the valve train.
slim_boy_fat
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Has the OP posted again in his thread? Might have scared him off with conflicting and contradictory input from Members?
Parm
Respect The Sound System
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Spot On. Exactly the reason why there has been some high profile "BANGS"
The situation im looking at involves 200 l oil drums. They were filled with petrol and then drained. No Liquid remained.
It was the residual vapor inside the closed drums that violently exploded as soon as the plasma pierced the lid
I have a fairly weighty report from our scientists that conducted experiments to confirm the situation as all the evidence was destroyed in the explosion
They worked out the exact stoichiometric ratio required. In lay mans terms it amounts to half a teaspoon of petrol
daleyd
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I can’t remember if I still have the video but I used to work in the printing industry - one of the products we made was hot air dryers for heat set magazine printing. The exhaust rates were calculated with safety factors included and they were worked out as something like 4 x the amount of ink/solvent the press would deposit when running at full speed - which basically meant the flammability level should never be more than 25% of the LEL (lower explosive limit).
Which is all great until a printer comes along with a squirty bottle of solvent to clean the plates with paper still going through the dryer
. It was from a cctv system and you could see the guy doing it, and shortly after the pressure relief doors parting company with the dryer 
maz0
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He will soon learn, its one of mig-welding forums favourite horses to flog! Lab coats and spectacles come out.Has the OP posted again in his thread? Might have scared him off with conflicting and contradictory input from Members?
Hopefuldave
Intergalactic pot-mender
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https://ps.uci.edu/scholar/sites/default/files/understanding_a_clathrate_hydrate_2010_1.pdf is a brief but (pop-science) educational resource on clathrates - it's suggested that the Deep Water Horizon drilling rig was victim of a clathrate explosion...
Dave H. (the other one)
Dave H. (the other one)
Parm
Respect The Sound System
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I can’t remember if I still have the video but I used to work in the printing industry - one of the products we made was hot air dryers for heat set magazine printing. The exhaust rates were calculated with safety factors included and they were worked out as something like 4 x the amount of ink/solvent the press would deposit when running at full speed - which basically meant the flammability level should never be more than 25% of the LEL (lower explosive limit).
Which is all great until a printer comes along with a squirty bottle of solvent to clean the plates with paper still going through the dryer
CCTV is brilliant. Fortunately for me, but unfortunately for the deceased et al, I’ve got full video of the man being killed from the drum explosion. It was instant
brightspark
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cant press the like button. not good when something like that happens. we all have made mistakes . some we get away with and some we don't
Parm
Respect The Sound System
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That’s just plain stupid
Memmeddu
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Surely it's not advertisable but it's the only way to be sure that there is nothing left inside
Parm
Respect The Sound System
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Lol, not the only way
Memmeddu
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Probably right
