Welding Tips and Tricks

what is the correct settings for oxygen/acetylene when using a rosebud for heating a large area? I have been told they should be the same/balanced ???????

Bobby wrote:what is the correct settings for oxygen/acetylene when using a rosebud for heating a large area? I have been told they should be the same/balanced ???????

The troubleshooter for local Airgas is good! He says 5 & 6 LBS.

Maybe you know this, but a rosebud requires a fairly large acetylene tank. I can't remember the details anymore, but you need to look at the flow of the rosebud and make sure that doesn't exceed some fraction of the capacity of the tank. Otherwise you'll start drawing acetone out of the tank which can be dangerous.

Withdrawal rates are different summer and winter, or first minute. I tend to forget that many have little tanks. Mine are the biggest I can get.

cj737 wrote:http://www.esabna.com/eu/literature/old ... -cw500.pdf

I would like to highlight pages 10-11&12 in the previously mentioned manual.

MarkL wrote:Maybe you know this, but a rosebud requires a fairly large acetylene tank. I can't remember the details anymore, but you need to look at the flow of the rosebud and make sure that doesn't exceed some fraction of the capacity of the tank. Otherwise you'll start drawing acetone out of the tank which can be dangerous.

Your referring to the 1/7th rule. This applies to everything you do with acetylene weather it be heating or cutting. This is one reason why acetylene regulators have a red line on the 15psi setting. This setting is never to be exceeded.

snoeproe wrote:Your referring to the 1/7th rule. This applies to everything you do with acetylene weather it be heating or cutting. This is one reason why acetylene regulators have a red line on the 15psi setting. This setting is never to be exceeded.

The 15psi red line on the regulator addresses a different concern. Acetylene is unstable and decomposes explosively above 15psi, that's why the red line on the regulator.

Drawing too high a flow rate (regardless of what the pressure is) causes acetone to come out of the tank, which is explosive and damages things. This motivated me to go and review the rule, turns out OSHA issued new rules in 2003, they replaced the 1/7 rule and now say no more than 1/10 the volume per hour for intermittent use and no more than 1/15 for continuous use. So for my 80cf tank I really shouldn't use a welding tip larger than #3, let alone think about a rosebud. I often use a #7 tip to heat things, guess I need to stop doing that.

or 100lbs propane tank and go up a rosebud size or two and forget about tank withdrawal rate.
i run all my oxy fuel torches on a 20lbs propane tank.. only acetylene tourch i have is a small AIR acetylene one kinda like those little propane ones u put on the disposable tanks.. that i use for automotive work.