Oxy-Fuel Cutting

[Liquid_Pyro]

When setting up an oxy-acetylene torch, the recommended procedure is to only open the acetylene cylinder a 1/4 to 1/2 turn and the oxygen cylinder open all the way.

What about other fuel cylinders like propane, "MAPP" and propylene?

I believe oxygen is to be opened all the way due to the fact that the oxygen can leak past the valve if not fully open or closed.

Cracking fuel cylinders a recommended practice?

Also do all fuel cylinders have fusible plugs built into them? (even a BBQ propane tank?) and do all oxygen cylinders have a bursting disk?

Thanks

[Liquid_Pyro]

No one?

[Stick-man]

I use propane and I only open (any) fuel cylinders partially. This is so in an emergency, should I have the nads to go and shut off the fuel, I can shut it off quickly!

Yes, the oxy valve is prone to leakage if it is not fully opened.

[DSW]

...and do all oxygen cylinders have a bursting disk?

In the US, all high pressure gas cylinders will have a burst disk. The disk is usually rated at roughly the hydro pressure of the cylinder. The disks are garanteed to blow at or BELOW the rated pressure for the disk. It's not uncommon for disks that have been subjected to multiple fills to go at signifigantly less than the rated pressure. In Europe however, I don't believe burst disks are required.

[forhire]

Not to state the obvious. When opening a cylinder full open, I always turn it back a little... so nobody comes along later and attempts to "open" an already open cylinder This prevents valve damage.

[Liquid_Pyro]

What about propane cylinders, should they be open all the way? I know acetylene is only a 1/4 turn, but I dont know if that applies to all types of fuel....

[mckutzy]

I have a corollary to the previous statement by Liquid_Pyro - Should Propane cylinders be fully open when using a torch or a roofing torch that isnt necessarily using oxy. A roofing friend stated that they were having to open the valve fully open in order to use there torches cause of freezing and flow restrictions. Iam of a welding background and know the rule of thumb just crack the fuel bottle/oxy full open and this is because of safety in an emergency, but Propane is a different gas than Acetylene?

I still think his way is wrong and I even practice the standard rule even using the BBQ, I am wrong?

[farmall]

If you get enough flow for your application, then there is clearly no problem with not opening LP valves all the way. I don't open mine fully either but I'm not running monster rosebuds or anything requiring lots of flow.