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I am just getting into oxy-acetylene welding/cutting (I have yet to strike a flame, maybe because I'm overly cautious, especially with the noises I've encountered)To start, I have a full 80cf oxy tank and a full 40cf acetylene tank. I bought the basic, Harbor Freight welding kit ($149, #98959). I heard enough good reviews and even had it in our local Airgas shop where the guy said "this is really nice," for what that's worth. While at Airgas, I picked up a set of Radnor/Western Enterprises flashback arrestors. The Airgas sales guy suggested removing the check valves that come installed on the HF torch body and only using the flashback arrestors so I wasn't restricting flow too much. I figured, "why not double my safety and just leave the check valve on." Maybe this is my problem.I got everything all hooked up, but when I went to purge the the hoses/torch, I got this clattering or gurgling, almost bubbling sound coming from the vicinity of the check valves/flashback arrestors installed at the torch body. It occurred on both the oxygen and the acetylene side individually. I was freaked out, shut everything down, purged everything, back to zero. I did a little tightening and started over. Same result.Thinking something was defective, I returned my kit to HF for an exchange. Of course, the regular kit is out of stock and none on order. My option was to drive to the next closest store (not that close) or upgrade to the Heavy Duty/Industrial torch kit. I bit the bullet and paid the extra.Day 2, Take 2 - I go through all the set-up with the new kit. Go to purge the hoses/torch. Same gurgling noises. This time I leave everything pressurized and check every connection for leaks (like 8 times on every connection). No leaks.So my question is, should I not have the check valve and flashback arrestor in series? Does that cause a problem? Are the noises anything to be concerned about? I found one other reference to this and it seemed like they were told by the company that this wasn't a big deal.Because I'm new, I feel like I'm standing 6 inches from two bombs even though I've seen so many videos of experienced welders nonchalantly going about their business, all using slightly different methods and start-up and shut-down procedures. I'm just someone who wants to know every little detail and this noise is bugging/concerning me.-dan
Reply:Flashback arrestors have check valves in them as well so you can take the other ones off. Did you get flashback arrestors for the torch or the regulators? Reason I ask is because they are one way and can't be interchanged. Try the torch the way it came first. If that's OK, then take the check valves off and try it with the flashback's.
Reply:It's great that you're being so cautious...too many people are the exact opposite!! Like Dave said make sure you have them installed on the right end of the hose. I would leave the origional ones off and give it a shot. I'm assuming when you were messing with it and then bleeding it off you were getting flow, otherwise it wouldn't have bled off. In this case there's no reason it shouldn't work!!Good Luck and have fun!!-DoogieMiller 350PMiller Trailblazer 325 EFI w/ Excel PowerLincoln LN25 suitcase welderXMT 304/22a feederMiller Syncrowave 350LXMiller EconotigHobart Handler 140(2) Uni-Hydro 42-14Hypertherm 65 plasmaWEBB Gap bed lathe
Reply:Originally Posted by Welder DaveFlashback arrestors have check valves in them as well so you can take the other ones off. Did you get flashback arrestors for the torch or the regulators? Reason I ask is because they are one way and can't be interchanged. Try the torch the way it came first. If that's OK, then take the check valves off and try it with the flashback's.
Reply:Originally Posted by derekpfeifferIt's great that you're being so cautious...too many people are the exact opposite!! Like Dave said make sure you have them installed on the right end of the hose. I would leave the origional ones off and give it a shot. I'm assuming when you were messing with it and then bleeding it off you were getting flow, otherwise it wouldn't have bled off. In this case there's no reason it shouldn't work!!Good Luck and have fun!!
Reply:That also leads me to another question, and this could also be related to the check valve plus flashback arrestors restricting flow. My working pressure dropped significantly when I opened the lines to purge. Like most of the instructional things I read and watched, they tell you to dial in your working pressure. Then they go about their purge but no one ever addresses what will (or won't) happen on your gauges.I took the drop as a leak, but as I said, I did so many leak tests that, even being completely new, I'm confident that there are no leaks.I then finally found one instructional video where they cracked the torch valves BEFORE they dialed in the working pressure to allow for, what they made seem like, an inevitable pressure drop when you open your torch valves. I was under the impression that the working pressure gauge should stay rock-solid when you purge your lines, but maybe I'm mistaken. In this video, they showed the gauges and I finally was able to see the needle drop drop a couple psi when the valves were opened.Possibly the double safety devices are exacerbating this pressure problem which is leading to less pressure and the gurgling.I'll definitely try to run the the set-up with only the original check valves and go through the purging and see if it eliminates the noises. If so, I'll then swap the check valves for the flashback arrestors and redo the purge and see if that works.Thanks guys.-dan
Reply:Yes you will loose pressure when you open the valves.-DoogieMiller 350PMiller Trailblazer 325 EFI w/ Excel PowerLincoln LN25 suitcase welderXMT 304/22a feederMiller Syncrowave 350LXMiller EconotigHobart Handler 140(2) Uni-Hydro 42-14Hypertherm 65 plasmaWEBB Gap bed lathe
Reply:Originally Posted by derekpfeifferYes you will loose pressure when you open the valves.
Reply:Just to eliminate some variables, how about removing both the check valves AND the arrestors. Then you can see if the torch makes the noise... then add check valves to see if they make the noise... then remove check valves and add arrestors to see if they make the noise.
Reply:Originally Posted by sndngrvlSo should I compensate for that when I set the working pressure? For example, if I want to use 7psi acetylene, should it be set to 9psi, etc., assuming I'm going to lose a couple psi when the valves are open?
Reply:there is a website called tinmantech..look there for a description of how to light a torch. your caution is to be applauded.
Reply:Thanks for the replies. I haven't had a chance to test the different set-ups yet today. I feel comfortable with all the hook-ups and I have a good grasp, at least informationally, about lighting and adjusting the flame. It's just these couple middle stage, uncertainties (the noises and the pressure drop upon valve opening) that has me in temporary limbo. I'm heading out now to try the different check valve/arrestor configurations. I shall report back.-dan
Reply:The only time you'll ever need more than about 4 PSI acetylene is with a rosebud. What are you trying to do with your new torch, weld or cut? If you want to balance your tip for welding, there's a better technique than what's posted in your owners manual that doesn't rely on what your regulators say. I think I told another poster on here how a couple weeks ago.
Reply:Originally Posted by Welder DaveThe only time you'll ever need more than about 4 PSI acetylene is with a rosebud. What are you trying to do with your new torch, weld or cut? If you want to balance your tip for welding, there's a better technique than what's posted in your owners manual that doesn't rely on what your regulators say. I think I told another poster on here how a couple weeks ago.
Reply:UPDATE: I did manage to get out yesterday and try the different check valve/arrestor combos. I first removed the arrestors and pressurized the system with just the pre-installed check valves. There was a similar quick gurgle but it seemed to mostly subside.I then removed the check valves and installed only the arrestors and there didn't really seem to be much, if any, of the original unsettling gurgle. The one change I did make when trying both set-ups was to crack the valves on the torch as I was dialing in my working pressure. For example, with the acetylene valve on the torch cracked, I dialed it in until I got 5psi. When I closed the acetylene valve on the torch, it bumped up to about 7psi. (same procedure with oxy - dialed into 15 psi with the valve cracked and it jumped to 25 once I closed the valve)I have a hunch that the check valve + the arrestors original set-up was stealing too much pressure and the combo was creating the problem because I wasn't starting with enough pressure anyway (just dialing in working pressure with the torch valves closed).I did get 'brave' and light the acetylene and adjust it to the proper, non-sooty state but the wind was pretty gusty and the flame was whipping around pretty good so I called it off before I started messing with the oxygen. I'm not sure what amount of wind, if any, is acceptable when working outside, but I didn't want to take any chances.I feel one step closer, though.
Reply:You may want to invest in the smaller size cutting tip. A 40 cf acetylene cylinder doesn't have much volume in it. The general rule is to stay below 1/7th the cylinder size for withdrawal so the acetylene can "boil" out of solution without becoming unstable, or sucking the acetone out of the cylinder. The acetone is hard on the soft reg parts.I don't have the link to the flow chart for various victor style tips on this computer, but my 75cf cylinder is borderline for anything bigger than the smallest 2 sizes IIRC. If I get a chance when I get home tonight, I'll post the link I have on that computer.You are fine as long as you aren't cutting continuously and give the cylinder a chance to recover between uses by shutting down when you aren't actually cutting. With welding/brazing light stuff, you shouldn't have any issues, but rosebuds draw more than even my set up can supply except for very short uses..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I do still have an extra #0 tip I bought for the first torch kit. Is that still overkill, or borderline acceptable? I looked up the Victor chart and it lists a 00 tip for 1/4", however, I also threw out 1/4" as a guess for the thickness. I've never actually measured it but it's pretty close. I'll measure it to be sure.If a #00 tip is the correct choice, I'll have to run out tomorrow and get it since our Airgas isn't open today.-dan
Reply:You should be OK. You don't have to turn the acetylene all the way up, just enough to get rid of the black soot and then add oxygen. It's common for regulators to read slightly higher when the torch valves are closed. 00 tip would be kind of small.
Reply:On of teh tings we did when I took my 1st welding class eons ago was to learn to cut with an OA torch. After we had welded up a chunk of 3x3 angle doing pads with stick, we'd cut the angle into 2" pieces to practice OA cutting. Part of the "trick" was being able to cut from thin top thick by changing travel speeds and warming up the stock 1st. Even though a small tip like a 00 or 0 wasn't rated for 2 1/2" thick or so, we could still cut thru it without too much trouble as long as you didn't get ahead of yourself and loose your puddle. It's the O that really does the cutting, not the acetylene. In fact the instructor did that same cut by turning the acetylene off after he got the puddle running to show it could be done..No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:I've never heard a torch gurgle but I've only used victor in class and smith at home. That creeps me out. Almost wonder if you got reverse flow from maybe oxygen back into acetylene. Don't necessarily trust the check valves - they are mechanical. Flashback arrestors are a screen that snuffs a flame. If You bought kit 98958 (there is no 98959 on the website) then your original torch came with FBAs and check valves. Adding any more is dangerous. Glad you stopped.The industrial version says it has "blow-back check valves" - that's redundant and weird. And that raises the hair on my neck and makes me wonder what is actually built in (victor builds in combo FB/cv) or installed on the torch. Hfreight vendors make so many things and change stuff without warning. If it were me (and I know it's not) I'd go get a name brand Harris, smith, victor, etc torch and work from there. Oh, and a good set of regulators. They will last forever. Call me a p-ssy but I'm generally okay with knock offs for band saws, hammers, band aides, and t shirts. Not so much with elevator cables, heart implants, and OA torches and regulators. One other, not sure about your neck of the woods, but most of the big name counter staff in my area knows less than nothing about OA equipment. The vendors tech reps do know and should be your source for any add on flashback arrestors and check valves, including replacements.Stay safe!
Reply:Originally Posted by RodJHfreight vendors make so many things and change stuff without warning. If it were me (and I know it's not) I'd go get a name brand Harris, smith, victor, etc torch and work from there. Oh, and a good set of regulators. They will last forever. One other, not sure about your neck of the woods, but most of the big name counter staff in my area knows less than nothing about OA equipment. The vendors tech reps do know and should be your source for any add on flashback arrestors and check valves, including replacements.Stay safe!
Reply:UPDATE: (FINALLY!) I actually got everything fired up today. I downsized to a #0 cutting tip and I managed to cut one 3"x3"x12 foot section of angle iron from my truck. It required 5 cuts (or 10?) because I had to cut the steel in 2 dimensions in 5 places.Calling it a 'cut' might be pushing it. These were the jankiest, most jagged things you've ever seen. I feel confident in saying that they were the worst cuts any person who has ever used a cutting torch has ever made. Seriously. That's barely a joke. Granted, my last few cuts were slightly 'better' but I had slag everywhere and plenty of spots that had re-welded themselves. I had to give most of the connection spots a whack with a sledge to break it free, but it's no longer attached to the truck so maybe that's something. The steel also has a thick coat of metal primer paint (which I tried to remove as best I could) so I think that affected some of the cuts. Also, this was all done at really awkward angles so I feel like I could do better if the steel was just sitting on a work bench, like every instructional video I've ever seen, but all I care about is getting the steel off the truck and I can be fussier later when I need the steel for a project.Would I prefer not to have what amounts to razor wire at every one of my cut locations? Absolutely. But the fact that one piece of my truck is now detached and is sitting in a pile for later re-purposing is a start.Thanks to everyone that was nice enough to chime in. I've put every little bit of that info to use so far.-dan
Reply:check-valves rattle. your h/f checks are probly very basic "spring-checks"since you bought what im assuming to be good flash arrestors, ditch the check-valves and you'll have a quiet setup.not that the spring-checks are hurting you otherwise, just imagine your reg set and line pressurized, valve off. when you open the valve, the gas overcomes the spring pressure, goes through the valve, and begins depleting line-pressure until your check audibly closes. your reg decides its not keeping up and gives you more gas and the check opens.depending on line pressure vs spring-rate, this noise can be a clack-clack-clack, a gurgle, a buzz, i have heard them all in the wide world of ill-designed piping systems. wind is a non-issue. light up and burn some metal!bosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:good to hear your doing it!!just remember, that these setups are very simple and fairly safe once you understand them. nothing burns without oxygen, and oxygen doesn't burn without fuel. your checks and flash-arrestors are in place for freak accidents, a seal failure or maybe clogged tip can cause your 25psi oxy to back-flow into your 7psi fuel, making an explosive mix in you're lines.i have experienced all kinds of failures with torches, and worst case has so-far been a hot torch and loud whisteling noisebosses stuff:trailblazer 325maxstar 200my stuff:sa 200fronius transpocket 180100 amp Lincoln w/f97 f350 DITKevin
Reply:I bought a similar kit to what you have from Princess Auto up here north of the border and got less than stellar results. Keep checking that hose for cracks and leaks...mine lasted less than 2 yrs and was not in the sunlight. The regulators are nicely chrome plated and have lots of metal, but that just makes them pretty, not good. I also noticed that the regulators dropped significantly in pressure when the valves were cracked so like you, I did final adjustments with them open. Double check your instructions for the proper pressures for the tips you are using... your O2 sounds a little low compared to what I've been using. The same tips for the Chinese lookalikes may say "Victor style", but that doesn't make them rated the same as the real Victors. You may find their pressure recommendations higher than a Victor tip of the same number. My biggest complaint was the seal ( or lack of ) at the levered O2 valve. I came to the conclusion that it was a bigger fire hazard than it was worth. I still use the Chinese handles for welding, but I tossed the cutting torch and regulators after fighting with them for a couple years and got a new set directly from Victor.250 amp Miller DialArc AC/DC StickF-225 amp Forney AC Stick230 amp Sears AC StickLincoln 180C MIGVictor Medalist 350 O/ACut 50 PlasmaLesOriginally Posted by 92dlxmangood to hear your doing it!!just remember, that these setups are very simple and fairly safe once you understand them. nothing burns without oxygen, and oxygen doesn't burn without fuel. your checks and flash-arrestors are in place for freak accidents, a seal failure or maybe clogged tip can cause your 25psi oxy to back-flow into your 7psi fuel, making an explosive mix in you're lines.i have experienced all kinds of failures with torches, and worst case has so-far been a hot torch and loud whisteling noise
Reply:Originally Posted by whtbaronI bought a similar kit to what you have from Princess Auto up here north of the border and got less than stellar results. Keep checking that hose for cracks and leaks...mine lasted less than 2 yrs and was not in the sunlight. The regulators are nicely chrome plated and have lots of metal, but that just makes them pretty, not good. I also noticed that the regulators dropped significantly in pressure when the valves were cracked so like you, I did final adjustments with them open. Double check your instructions for the proper pressures for the tips you are using... your O2 sounds a little low compared to what I've been using.
Reply:@ 92dlxmanYour use of the word 'buzz' might also be a good descriptor, close to what I called gurgling. It happened as I initially purged the hoses. I increased the pressure a couple psi and it seemed to mostly alleviate the sound. I never mentioned it, but I could also feel it as a bit of vibration. I would relate it to after you do some plumbing work and have to purge the air out of the pipes (or a garden hose with air). Until the last air bubbles get out, it's just not smooth and kind of sputtery. Maybe it's as simple as that. I didn't notice it at all when I had the torch fired up.And I think I did pretty well adjusting my flame (this actually seemed like the easiest part, to me). I sharpened up my pre-heat cones and when I hit the oxy lever, they didn't budge.The one thing I was surprised about was how quiet it actually was. I was expecting a roar like when a hot air balloon hits the gas. Or like my propane weed torch I use, which I wear ear protection for because it's pretty loud. This was almost nothing and even a smooth and quiet "ssssssssssss" as I was cutting. And again, I use the word cutting loosely. It's really more, as I created slaggy, serrated edges on everything.-dan
Reply:I can't remember if anyone has mentioned this or not yet in this thread. You might want to look at this thread and see if some of the info helps. Wayne did a great job on the videos.http://weldingweb.com/vbb/showthread.php...-cutting-torch.No government ever voluntarily reduces itself in size. Government programs, once launched, never disappear. Actually, a government bureau is the nearest thing to eternal life we'll ever see on this earth! Ronald Reagan
Reply:Originally Posted by DSWI can't remember if anyone has mentioned this or not yet in this thread. You might want to look at this thread and see if some of the info helps. Wayne did a great job on the videos.http://weldingweb.com/vbb/showthread.php...-cutting-torch |
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发表于 2021-8-31 22:40:45