Oxy Propane

[IDP]

Greetings,

Some advice please!

I have an oxy / acetylene torch which I use for boiler bashing, I am thinking of replacing the acetylene with propane which is cheaper and easier to obtain in my neck of the woods. I did take some advice from local dealers, one of which suggested I needed a new gun or at least a new mixing chamber, the other stated that the gun used with acetylene would be fine with propane without any modification.

Does anyone have any experience or advice to offer.

Regards,

IDP

 

[Kermit]

http://www.cousesteel.com/AndysPlace/PropaneAcetylene.html


have a look at this.

Kermit

 

[kf2qd]

Oxy/Propane works fine for heating and cutting, but doesn't work very well for welding and fine work.

The difference is that the heat in the acetylene flame is oncentrated in the inner flame and thus is easier to pinpoint and controll for welding. The propane flame has as much heat in the outer flame as in the inner flame so it spreads the heat out more. There is more heat in propane for a given volume of gas burned, but since it is not as concentrated it does not perform as well for welding. I have made a rather ugly weld on 3/8 steel with oxy/propane but it would not have worked on thinner material. I have used oxy/acetylene to weld tin can material because I could control the amount of heat input. Cutting tips are different for propane and acetylene.

Personally I like my propane torch for cutting and heating much more than an acetylene torch. Still use acetylene for welding and brazing of small pieces because I have more control over the flame and heat.

You will need to replace parts in your torch, different mixer and tips, or better yet get a new torch for working with propane then you can use whichever you decide works best for the job.

 

[Stan]

I have a Victor 100 torch head that was formerly used on acetylene. When I changed to propane (about 1960), I bought a couple of propane cutting tips. The propane cutting tips are completely different construction (two piece) but fit the same way as the original acetylene tips. The propane tips are easily damaged if you are cutting overhead and slag falls on the tip.

I actually prefer propane for cutting although the preheat time to start the cut is longer. For simple brazing jobs I just use the cutting torch for heat. For silver soldering anything that is too big for the propane throwaway bottles I use the propane cutting torch. I bought one of the small plumber bottles of acetylene to use if I really have to gas weld.

 

[lordedmond]

propane has to much carbon in it for use as a welding gas , has stated above fine for cutting and heating but no good for welding.

its a dirty gas thats the reason its cheaper

 

[IDP]

Folks,

The reason I posed this question :~ I have acetylene which is great for brazing copper boilers etc but I may not be able to easily get my bottle refilled when it's empty. There is no problem with my bottle but the local supplier requires a rental contract the cost of which is prohibitive for the amount of brazing I actually do.

I was thinking that maybe oxy / propane would do the job for me but as it's a dirtier gas then I guess it might not be the best way forward for brazing loco boilers ~~~~looks like paying the bottle rental!

Regards,

IDP

 

[PTsideshow]

As been stated in previous posts, you can not achieve a neutral flame with the oxygen/propane. Thus causing contaminates in the weld join. Leading to problems.

Acetylene is the only gas that can be used for welding.

The other consideration if one chances, from acetylene to another fuel gas is the type or grade of hoses.

Grades R, RM, or T can be used with Acetylene gas.

Use grade T hose ONLY with MAPP,PROPANE,PROPYLENE

As the ingredients used in the gas attack and can cause a failure in the hose.

If your LWS, won't exchange the acetylene cylinder, then they will do the same with the oxygen cylinder.

As it may be a case of the prevailing practices in your area that the size of the cylinders that you have are rentals/leases only and available for (private ownership) as most area deal with the two largest sized ones.
The name of the company that owns them will be around the neck of the cylinder.

In the US it is against the law for a gas supplier to have a foreign cylinder (non owned by them on their property) The LWS i use has 25 single 8x10 pages of named cylinders the company owns. (Airgas)

I understand that Praxair has about the same.
;D

 

[Stan]

IDP: I don't think you would have a problem with joint integrity using oxy/propane to silver solder. The flame is used strictly as a source of heat and when done properly the flame is not in contact with the metal where the joint is being made. The heat should be applied away from the joint so that the molten silver solder is drawn toward the heat.

When I have to silver solder a piece of metal that is too large for the throwaway propane bottles but not large enough to warrant a trip to the cold garage to use oxy/propane, I just set the workpiece on the cook stove burner.

In my previous post, I mentioned buying a plumber's acetylene bottle. Laws and rules are different in every area but where I live plumbers use an acetylene/air torch when using higher temperature solders for things like air conditioning lines. They buy these bottles and return them for exchange without needing a gas bottle contract. I think they are 40 cubic feet (about 20" tall by 6" diameter).

 

[PTsideshow]

The acetylene cylinders, Stan is referring to next to the old style tall thow away cylinders.

Here is the adapter that you will need if you get the MC cylinder (motor cycle)
The B cylinder (bus cylinder) doesn't need any adpater for the air/acetylene torch kit.

To different brands of the same style Prest-o-lite torches