Oxy-Acetylene torch safety question

To meet the utmost in safety requirements, you should have flashback valves installed at both ends of the O2 and the C2H2 hose connections. There is a small arrow that indicates direction of flow stamped into the valve. Keep in mind that flashback valves only stop reverse flow of the explosive gas mixture during a backfire. They DO NOT stop a flame. To do that you need to install flame arrestors. You can buy flame arrestors with flashback valves built-in.

We also equip our customers with quick release chucks ( similar to an air chuck) that have flashback valves built-in. Handy if you frequently swap out torches. (Cutting torch to welding torch or powder torch)

Victor makes a Vangaurd series that has flame arrestors and flashback valves built into the handle.

You can check to see if you have flashback valves in your handle by peering into the end of the handle where the hose connections are. You would see a small flat plate that is spring mounted on the blind side. It just slams shut during a 'pop' or backfire.

The after market flashback valves look like a small nut with an arrow on it. These don't last a lifetime either. You should replace them at some point.

There is too much additional info to list here regarding handling of the cylinders and so forth. It takes me two hours to go over this in a safety seminar. Perhaps I'll prepare a torch safety page for our web site at some point.

4. Don't draw more gas out of the Acetylene tank that it is rated for - whatever volume that is?

(I'm a dummy on these safty issues as well, but this stuff is contained within a resin in the tank, and really bad things happen if these 2 rules aren't followed. - I run oxy-propane myself.)

--->Paul

Why take the chance?

The flame arresters came out in the 70's because of accidents. I've seen three types but there could be more. One is style is located built-in on the mixing body just ahead of of the gas valves. They'll have a large plug that screws into the mixing body.

Another style attachs to the mixing body hose couplers before the gas hoses are attached then the gas hoses attach to the flame arrester. There made of brass.

The other style attachs on the gas regulators output flow nipple then the hose attaches to the flame arrester. There also made of brass.

T_Bone

Personally, I use LP for 100% of my cutting work. It's safer, cheaper, cleaner and faster than acet if used properly with the right equipment. Many will beg to differ on this and I don't want to get into a battle over fuel gases here.

I have both flow direction check valves and flash back arrestors on all my torch equipment. Like T_Bone said, the old ones went between the regulator and hoses or mixing vlaves and torch tip. New ones, both flame arrestors and check valves are made to screw in-line with the hoses and have the appropriate thread for gas and O2.

Flame arrestors will run about 15-20 bucks a set and check valves around 12-18 bucks a set depending on size, type and mfg. Personally, I use Western brand as they are commonly available here. "Flame arrestors" and "check valves" are two different devices. Flame arrestors have a fusible link that will melt when exposed to a per-determined heat causing the unit to stop gas flow. These are one-time use items, they melt shut, they get replaced. "Check valves" unless damaged by a fire or physically will work over and over again. They are nothing more than a spring loaded valve, just like those used in water lines, that limit flow to only one direction.

Suggested set up for use is as follows: Flame arrestor is attached to hose thread at regulator. Flow check valve is attached to hose connection on flame arrestor. Hose is attached to hose connection on check valve. Second check valve is then attached to hose connection on torch. Second flame arrestor is attached to check valve at torch, then the hose is attached to the flame arrestor. Duplicate for both fuel and O2 connections.

The reason for using both is to double the safety value of the equipment. If the torch "pops" and back pressure tries to push either fuel and or O2 back into the hoses, the check valves should function to stop the flow fast enough to snuff the fire inside the torch handle. If the check valves fail to snuff the fire, the flame arrestor should burn shut closing the flow of fuel/O2. If a sufficient amount of pressure is developed at the torch which causes the failure of the first combination of check valve and flame arrestor allowing flame to enter the hoses, the second combination of check valve and flame arrestor should prevent fire from entering the tanks causing a serious explosion.

If you have a flash back or hose fire, you should remove all equipment from service and have it checked and tested by an approved repair/testing facility. With the low cost of most smaller torch equipment, sometimes the most economical choice is to just replace it with new.

Don't take chances with safety. The small price to pay for a couple sets of check valves and flame arrestors is nothing compared to the price you will pay in being seriously burned or killed.