o/a torch problem

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I used my o/a rig this weekend... I had not used it in a couple of months, but there has never been a problem. I mounted the gauges and set them up like usual I set the oxy first and noticed the regulator just keep going and going. It pegged all the way. I had to open the valve on the torch to relieve the pressure. If I leave the valve open a little it will regulate if I close the valve it pegs out and finally relieves inside the regulator. I did the same w/ accetylene side same thing happened. What is the problem? What did I do now?
Reply:Did you clear the bottle valve before you turned it on? Sounds like trash in the valve.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:If you are getting pressure at the output hose and gauge when the adjuster screw is turned outward, your valve seat is leaking. As stated above, you might have dirt blocking the seal, or the seal may have hardened or cracked and be incapable of sealing. What brand of regulators have you, are they new or old, single or two stage, and were they still installed on cylinders or sitting in a box with the hoses also disconnected?
Reply:Lugweld, I did not clear it before installing! They had been sitting in a box for a couple of months.Update: I just went out in the plant and removed them blew them out and reinstalled. The oxy side is still not regulating. The acc. side is working properly. Sounds like I still have a problem.The brand is Smiths equipment. I am not sure if they are single or two stage. How can I tell? They are pretty old but we keep them in a controlled environment.
Reply:Nest step disassemble and blow out parts.  Re assemble carefully.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:I wouldn't recommend blowing out an oxygen regulator.  Any oil mist in your compressed air, left behind, can become explosive in the presence of pure oxygen at high pressure.
Reply:True. Use an oiless compressor.Esab Migmaster 250Lincoln SA 200Lincoln Ranger 8Smith Oxy Fuel setupEverlast PowerPlasma 80Everlast Power iMIG 160Everlast Power iMIG 205 Everlast Power iMIG 140EEverlast PowerARC 300Everlast PowerARC 140STEverlast PowerTIG 255EXT
Reply:Happened to me once.  Turned out to be bad seals on the valve seat.  Replace the seals.  Then always leave the valve turned in a bit to put pressure on the spring when you leave it stored or unused.  Close the tank valve, purge the lines, back the adjuster on the regulator off, then turn it in to put a little presure on the spring.  It keeps the seat seal from sticking, and tearing over time.Got this advice years ago, and I've never had to replace a seal since."Any day above ground is a good day"http://www.farmersamm.com/
Reply:COuld be as simple as a spider made a home in the hose. It happens. Clear the lines and you can clear the regs with one of those canned airs. Just dont turn the can upside down.
Reply:If you do try to blow it out, first crank the adjusting screw in to open the valve so anything caught there can be blown away. Do you have compressed CO2 you can use for it? Also blow in the hose outlet, but don't use too high a pressure doing it that direction.Two stage units have a second diaphragm section which reduces the tank pressure to an intermediate level which remains nearly constant until the tank is almost empty, so the delivery pressure doesn't change much with changing tank pressure.Samm is right about leaving a bit of pressure on the adjusting spring; it pushes against the closing spring, thus holds the seal(er) off the seat, [hope you don't mind my nomenclature].Last edited by Oldiron2; 01-05-2009 at 08:09 PM.Reason: Credit given to Samm!
Reply:Thanks, for ALL of your help. I'll give it a go today...I'll let you know what happens. I do have some canned air I can use.
Reply:We sent in a box of various regulators to be repaired a few months ago and ended up with 3 oxygen and 1 acetylene being bad.  Turns out that the diaphragms in that batch were bad.. It's taken us a few months to find them all.  Hopefully they are all gone because I have run into them in the field.  And I always crack my oxygen bottle before attaching the regulators to blow out debris.Common sense in an uncommon degree is what the world calls wisdom.
Reply:Well, I pulled the reg, apart and found no obstructions and found no bad looking seal. I guess I'll hit the lws and let them look at it.
Reply:I took the reg. to lws and they said the diaphragm needed to be replaced. $50.00 and a week to get it fixed. I wish I was pulling more jobs in right now to help cover the unexpected cost..... but what do ya do.
Reply:Mine does the same from time to time.  It sticks open (leaks) but all I do is take apart the regulator and wipe down the seal "guide" and put everything back together...dry.  It usually stops doing that the first time.  The guide is a little piece that sticks into the body that keeps the seal from wobbling around...kinda like a tire valve.