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http://www.lincolnelectric.com/en-us...on-detail.aspx I was doing some searches on options for preventing distortion or warping. One thing mentioned in this link was a water cooled jig. The concept sounds very interesting, but I haven't ever seen it or heard of it before. In fact, I don't really seem to be able to find anything else on the subject outside of this link and lots of stuff about water cooled tig torches. Does anyone have any opinion or insight into the concept? I am working on trying to implement this concept to see how it works myself, but I keep imagining either it taking away too much heat or too little. Plenty of people mention that putting water on a weld will cause the weld to become brittle, would this brittle idea occur similarly with a water cooled jig?I found a post earlier about intentionally putting water on some part of heated metal to undo warping or something like that. It sounds conflicting but there was a book suggested, maybe I'll give that a read. http://weldingweb.com/vbb/showthread.php?t=47275 This is the thread.
Reply:I was thinking about this last night oddly enough. I thought a big block with holes through it and using a torch cooler would be great for manifolds or headers to keep them from warping.Torchmate 2x2 CNC with Flashcut CNC controlsHypertherm Powermax45 Esab ET220i Razorweld 195 MigRazorweld 200ac/dc TigTormach 770, Tormach xstechRazorweld, Vipercut/Vipermig, SSC Foot Pedal Dealer
Reply:bowlingonsunshine, most jigs are sort of job specific and a water cooled clamping fixture would probably be most economical if the work were done over and over; otherwise the cost for copper, water cooled clamping or 'chilling' fixture is going to make any given weld cost higher.I'd say the more important question is "How to make a weld that is in proportion to the metal at the highest possible speed?" so the two main contributions of distortion are reduced. Dwell-time, rate of travel, duration based on arc time to weld, bead cross section versus parent metal and penetration versus bead cross section all add to the net wattage imparted to the parent metal based on the welding time and size of the weld. In my opinion, any distortion issues would be better addressed in the overall set up compared to trying to refrigerate the weld BTU's out of the parent metal.Dousing a hot weld will not necessarily reduce distortion and in many instances will create a metallurgy you won't want."Why look for an 'aspirin' for that headache, when you can just avoid the cause."cheers,Kevin MorinKenai, AK
Reply:What is it that you wanna weld? I have a large block of steel that I frequently use whe welding on a sheet of aluminum. It works to hold my material in place as well as a large heatsynch.RGRG_______________________Hobart 187Northern Tool Plasma 375Harris 85 O/A Rig (Ireland)
Reply:Most distortion is the result of the temp differential between the weld pool/HAZ and the rest of the metal. In most cases you would be better off heating the whole part and reducing that differential as much as possible.Lincoln precision TIG 275Millermatic 140 MIG
Reply:Originally Posted by yoshimitsuspeedMost distortion is the result of the temp differential between the weld pool/HAZ and the rest of the metal. In most cases you would be better off heating the whole part and reducing that differential as much as possible.
Reply:Originally Posted by bowlingonsunshineSo, you are saying that any who deal with distortion should grab a blow torch instead of a water pump.That is interesting, I've never heard of/considered that. When I think of using a blowtorch on something before welding it, I think of a really large object with an under powered welder.
Reply:Is it unwise to try and heat things up prior to welding them? I am wondering if people take a large torch to large metal things prior to welding. I imagine it would be hard to evenly heat large objects fast enough to get around distortion.I've got a 20 pound propane tank and I recently purchase some hose and a torch to attach to it, would I need anything else with it to just go to town practicing this concept? And, should I?
Reply:Personally when welding aluminum I heat it all in a oven, do all the welding I need to do, then let cool like mentioned. Welding on the part keeps it warm.Any flanges get bolted or clamped down to a good chunk of junk that is also heated with the part and holds the heat the whole while.A few good pics of jigging stuff in this thread: http://weldingweb.com/vbb/showthread.php?t=55452
Reply:Originally Posted by bowlingonsunshineI've got a 20 pound propane tank and I recently purchase some hose and a torch to attach to it, would I need anything else with it to just go to town practicing this concept? And, should I?
Reply:VPT: I've considered the idea of heating things in an oven, but the oven would need to be awfully large for many projects. Maybe a large oven will be a project in itself.Broccoli1: How exactly did you use of a mapp torch to straighten your project out?
Reply:Originally Posted by bowlingonsunshineVPT: I've considered the idea of heating things in an oven, but the oven would need to be awfully large for many projects. Maybe a large oven will be a project in itself.Broccoli1: How exactly did you use of a mapp torch to straighten your project out?
Reply:Originally Posted by bowlingonsunshineVPT: I've considered the idea of heating things in an oven, but the oven would need to be awfully large for many projects. Maybe a large oven will be a project in itself.Broccoli1: How exactly did you use of a mapp torch to straighten your project out?
Reply:The issue that keeps coming up in my mind is, wouldn't more warping create a whole lot of stress or fatigue to at least the welds themselves? Or is this simply irrelevant in steel due to fatigue limit?
Reply:Originally Posted by bowlingonsunshineThe issue that keeps coming up in my mind is, wouldn't more warping create a whole lot of stress or fatigue to at least the welds themselves? Or is this simply irrelevant in steel due to fatigue limit?
Reply:Excellent, thanks for the wisdom and guidance. |
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发表于 2021-8-31 23:30:16