Ethylene

[wannabewelder]

Hi
Does anybody know anything about the use of ethylene in welding?
SWMBO is studying floristry and was researching ethylene, which is apparently produced when flower stems or foliage are damaged and the ethylene acts to shorten the vase life of the flowers.
She checked on Wikipedia and it says "Approximately 80% of ethylene used in the United States and Europe is used to create ethylene oxide, ethylene dichloride, and polyethylene.[12] In smaller quantities, ethylene is used as an anesthetic agent (in an 85% ethylene/15% oxygen ratio), to hasten fruit ripening, as well as a welding gas.[12][13]
I presume it must be a fuel gas - but I could be wrong -- probably!!
I've checked the BOC site and can't see anything about ethylene.
Does anyone have any idea what it's used for?


Wannabewelder

 

[Hitch]

Never haers of Ethylene as a welding gas... them Americans have a different name for certain things.

The other name for Acetylene is Ethyne... Wiki explains a bit about it... Ethylene is used to make aceylene.... id think thats what they mean, perhaps.

 

[wannabewelder]

Thanks Hitch
That's probably it! I'll do a bit more research on the manufacture of acetylene.
I read the Wiki extract as that ethylene was actually used in the welding process - didn't occur that it might be used to make acetylene. Your chemistry knowledge is obviously better than mine!!

Regards

Wannabe

 

[Dangle_kt]

if it is an anesthetic then I wouldn't fancy my chances of welding straight!

 

[series2]

The other name for Acetylene is Ethyne... Wiki explains a bit about it... Ethylene is used to make aceylene.... id think thats what they mean, perhaps.

I think this is correct, the combustion products of ethylene are highly toxic.

 

[Omniata]

Ethylene is the monomer of polyethylene, two carbons linked by a double bond... Not much use in welding I'm afraid, but to the polymer industry.....

It is used for fruit ripening by exposing bananas and the like to it in chambers to increase their ripening rate...



For acetylene on the other hand is two carbons linked by a tryple bond, produced industrially at about 3 sites in the UK under license by dropping calcium carbide into water and collecting it...

One option that is offered is propene, or methyl acetylene. Accounts for about 30% of MAPP gas where another 30% is propadiene, the rest being LPG...
A safer alternative to acetylene that can be liquified as opposed to dissolved like acetylene...
The only side effect is that it's secondary flame temperature is hotter or as hot as the primary, meaning that the area around which your welding melts before the area your trying to weld

 

[chunkolini]

Sounds like another example of wikiballocks.

Chunkolini

 

[Omniata]

I tend to be very wary now on accounts some people update pages with nonsense just for the fun of it....

 

[RedOrZed]

I wouldn't believe anything on wikispodeida that I didn't already know...

 

[wannabewelder]

Thanks for all the helpful replies guys.
I find Wikipedia very useful as a rule and I can't recall any "whoopsies" in the past. It seems sad to me that anyone would want to deliberately corrupt what is an extremely useful tool - it's almost like coming on this forum and knowingly giving someone bad advice!
Thanks in particular to Omniata. I remember my father telling me about old motorbikes having acetylene lamps that required water and "carbide" and I seem to remember reading somewhere that "carbide" could be used for poaching salmon by creating underwater explosions - but perhaps we'd better not pursue that too much further!
Interesting too about the MAPP gas I didn't know of it's limitations - I just assumed that it wasn't a hot enough flame.

Wannabe

 

[pidgeon chit welder]

Thanks for all the helpful replies guys.
I find Wikipedia very useful as a rule and I can't recall any "whoopsies" in the past. It seems sad to me that anyone would want to deliberately corrupt what is an extremely useful tool - it's almost like coming on this forum and knowingly giving someone bad advice!
Thanks in particular to Omniata. I remember my father telling me about old motorbikes having acetylene lamps that required water and "carbide" and I seem to remember reading somewhere that "carbide" could be used for poaching salmon by creating underwater explosions - but perhaps we'd better not pursue that too much further!
Interesting too about the MAPP gas I didn't know of it's limitations - I just assumed that it wasn't a hot enough flame.

Wannabe

Calcium carbide used to be used in crow scarers where by water was dripped onto it , when the acetlene gas was produced at a set pressure it tripped a valve , released some gasand also caused the igniter to spark .... "Kaboom" out in the fields 24/7 in the old days .

Back in the mid 50's my old man came home with a lump about as big as his thumb .. he shoved it in a rat hole undeneath the big shed floor, chucked a can of water in it and then bunged the hole up. half an hour later he cleared the hole and threw some burning paraffin soaked sacking in the direction of the hole .. Big woof bang and bits of rats nest flew out of several holes , the sacking also came back & set fire to a heap of pig straw. Amazing stuff.

 

[scottfortune]

I too happened upon that Wikipedia article and paused to scratch my head at the mention of ethylene as a niche welding gas. But I did eventually find a plausible explanation in the form of a Japanese patent for a mixture of c. 20 percent ethylene and c. 80 hydrogen ( and "unavoidable impurities") intended to be used as safer ( especially in transportation) alternative to acetylene for use in oxy-fuel cutting, welding, brazing. This seems like a likely candidate for this reference from Wikipedia.