I have a large shop air compressor not sure on the specs I will look soon. The air compressor was given to me and it is a Speedaire and unit is about 6' tall. They gave it to me because the top of the tank had a crack about an inch long under the compressor mounting bracket running perpendicular to the bracket. So they gave it the heave hoe at about four years old. Any precautions I should take when welding it? I assume there should be nothing in the tank except moisture and I have left the drain open when stored. I can stick weld decent but now have a small wire feed welder I was going to use on this. I may practice on something else first. Second question is I wanted to use it for yard work on my Lulls and trucks with air tools and a small sand blaster gun. I have used 110 CFM compressors to run large sand blasting gun. I wanted to use this just for small touch up areas on my equipment where I can't sand easily. Any recommendations on a small gun brand. I guess I need to know the specs on the compressor first but I forgot them at the moment. I think it was listed at Graingers at abot 2 grand when I looked. It came from a dental lab where a ton of small air tolls used it on a line hook up. Thanks for any tips!:drinkup
I've welded air compressor reservoirs before with no problems. Old units usually have some oil in the tanks because of worn rings in the compressors. If you see a lot from the drain I would probably run some CO2 or argon in the tank to purge any oxygen. Grind out the cracks, drill the ends and weld it up. Good Luck!
Grind a V in the crack past the ends of the crack and weld it up i've done it twice with no problems so far. My friend used his for 2 years before upgrading to a big boy compressor. Its a miracle he never burned up the pump or motor.
Make sure the tank is vented to the atmosphere when welding. You don't want to build any pleasure in it from the heat. The tank is what is called a pressure vessel and requires a licensed welder by law in our state but may not in yours.
Although I can weld I am no expert. I may just skid mount it like I was going to so it is easily portable and truck it to my friend who welds and has a machine shop. I guess I could get a mobile welder to come also. I will be running it off my Miller welder in the yard or job anyway. He may worry about oil in there Since it was free I have a few bucks to splurge and I can't see it costing that much to fix. Thanks for the tips guys!:drinkup
A pressure vessel, even a small one, is an incredibly dangerous thing. Down here, you not only are required to be specially qualified for the various types of pressure vessel but you may have to register the repair and have it X-rayed. Its not something you can afford to mess with unless you are very well qualified.
yes I will skip the repair by myself
It may be a pressure vessel but it holds less than 200 PSI of air pressure. You don't store anything flammable in it so there is no fuel to explode. I only suggested inert gas as a way to subdue any flames from oil that might come through the weld. Speedpup, if you are uncomfortable with doing the repair then you are wise not to attempt it. Take it to someone who is competent and experienced. Good Luck!
ONLY 200 PSI? As a journeyman pipefitter we take any pressure vessel very seriously.The stored energy in air is incredible. At as little as 5 psi in a large vessel we wont even allow personell on the site. Dont even bother with the repair yourself. The crack developed for a reason and the thought of replacement is the only one you should be entertaining. Just to clarify this is in initial test situations that we wont allow people on site.
That tank if it is 2' in dia and has 200 PSI of air in it, exerts just a little under 100,000 lb. pressure on the total (452 sqin.) top area. (90,400 lb. to be exact) Nothing to mess with. and because it is air and not a liquid when released has a lot more stored energy.
If used commercially, you weld it and it never gives any trouble, you are home free. If it for some reason it lets go at the repair weld and injures someone, you will be in a world of trouble. These tanks are manufactured in facilities that are covered by government certificates. In other words, the manufacturer has to guarantee that the tank meets federal codes and the manufacture stamp is located somewhere on the receiver tank. Commercial use compressors are supposed to be inspected by law every few years by a certified inspector. I'm trying hard to remember all I know about this, but in California, I had to schedule the guy down from San Francisco and show him every compressor and receiver tank. Each one had it's own inspection identity number, and we were required to keep records of the certifications on file in the shop office. We had about six compressors at our main yard, maybe a dozen down at the fab shop on the other end of town, and about a dozen smaller units on lube and service trucks. The inspector had to look at every one, fill out his paperwork, then write up a tag that he attached to the compressor, which was supposed to stay on the compressor until the next inspection. You can imagine how well those lasted in the sun and rain as they were only little paper tags with a wire to attach them with. The mobile units on the lube and service trucks were the hardest to find as we swapped them around continuously as the engines and compressors let go. I eventually assigned equipment numbers to every compressor unit, and to the two or three separate receivers that we had at the fab shop that were not directly connected to a compressor. So, be careful if you weld and how you use the thing afterwards. Avoid trouble that you don’t need.
Speed, just a couple of thoughts. If this is in a closed in area that is for commercial use you may have insurance issues. The tank is probably an ASME coded vessel. I would wonder why the tank failed? Is there excessive corrosion in or on it? It is amazing the stored energy in a pressured up tank. Prior to going to medical school and while doing my prep work I worked in a specialty tool and hardware store. We saw many strange things and heard of accidents involving pneumatics, power and powder actuated tools. One I remember quite well involved a trim carpenter using a 3/4hp pancake compressor. The 4.5 gal. tank had a design flaw as the stamped half had too small of a radius on it's periphery. At full pressure the area failed instantly splitting about 33% of circumference on the bottom. This propelled the compressor at an angle through the 1/2" sheetrock ceiling breaking two 2"x6" ceiling joists in the process. Imagine what a 60 or 80 gallon tank would do!
Crack is on the top of the tank below the mounting bracket and about 1" long. My guess it cracked because of vibration from the compressor :beatsme. I'll take it to a certified welder and ask what they think. I'll post a picture in a few days. I am just going to use in in my yard myself but I don't need anything unsafe I have seen oxygen bottles that were missles.
I Think taking it to a professional is the right idea. The way YOU DESCRIBED IT THERE SHOULD NOT BE A PROBLEM.( sorry about the caps - hit wrong key) When I was a pup a lot of people made compressors out of old refrigeration units, putting on as many as needed - unfortunately they sometimes used water tanks- one blew the roof completely across the street- leveled the place, killing the owner
Yep and pay with a check and get a receipt
I have never had any trouble welding air tank's.Purge,grind out the crack,and weld it up.I use 6011 rod,mig welder work's good to.Good luck with it.
I think this is it http://www.grainger.com/Grainger/items/1WD58 I see it says ASME tank. I know when I looked at replacement tank it was 1200 bucks! I don't think it was corrosion at the top and the crack looks clean no rust. Sad part is I called my welder / machinist and he died 5 months ago. I knew him since about 1983. He made stuff for my race boat and could fix about anything. Saved me thousands years back when a planatery went bad on my Lull. Guess I'll write Ray on it now. He was about 63-4. His wife got cancer then his daughter, and then him lastly. They recovered but I guess the prostrate cancer got him. He got it about a year ago or slightly longer. God Bless Ray.
Wow! I look's like everything is going up in cost.Weld up your tank or have someoune weld it for you.I have been welding on truck's and equipment for 25 years,the skill has saved me alot of time and money.I think that compressor will work on small sandblasting job's.Hope this helps.
If I try it I guess I can purge it with nitrogen I use in race car tires as it is inert? Now stick or my 110 wire feed? I have 6011 rods and 7018. I have built 3 flat bed truck bodies, mortar buggies and diesel fuel tanks over the years and all the other miscellaneous repairs. My friend Ray did the higher tech stuff. Screw it I may give it a try. Not the money just the PITA to drag it somewhere or get someone to come. I got it for nothing so if I put even 200 to have it welded it would still be a steal. No clue what to do. May have the GF look up a welder. :Banghead:Banghead:Banghead Then I need someone to wire it to run off my Miller welder generator. ointhead
Welding a air compressor tank: Hello Speedpup, If you're going to attempt a repair, and if you're fairly handy with stick welding, I think 7018 would be the best rod to use. We've got a Hobart 220/240v wire feed (Mig), and a Hobart 110v wire feed. Personally, I'd stay away from the 110v... they seem kinda harmless to me, and I really don't care for it... although, it's better than nothing, and will work in a pinch. Nitrogen is not totally inert, but it will work for your application. That looks like a really nice compressor; I checked you're link... :thumbsup But, it's got a three-phase motor... will your Miller welder generator run three-phase? The above is not necessarily meant as advice... just something to look at, or be aware of... :cool2 And, I'm very sorry to hear about your friend Ray... Be careful, and good luck, OCR...
BOARDMAN, Ore. -- A welder has died in an industrial accident at ConAgra Foods Lamb Weston in Boardman, authorities said Tuesday. Kevin Paul Gregerson, 21, of Hermiston, was reportedly buried in debris after an explosion inside a tank, reported The East Oregonian. Boardman fire and police departments, along with the Morrow County Sheriff's Office responded to a call at 12:47 p.m. Monday at the potato processing plant at 600 Columbia Ave. N.E. A small confined space rescue team also was called. Gregerson's body was recovered just after 8 p.m., the newspaper reported. Stephanie Childs, spokeswoman for ConAgra Foods, said Gregerson worked for one of the company's contractors. He reportedly worked for Northwest Metal Fabricators. "We're in the process of doing everything we can to understand what happened," Childs said. "We're definitely looking into the matter. We consider this to be a very unfortunate incident and extend our deepest sympathies to the family." Melanie Mesaros, spokeswoman for Oregon Occupational Health and Safety Administration, said officials were at the tank Tuesday investigating. Mesaros said officials would generally look into what kind of training and supervision the employee had. They would also look at the company's safety policies. Oregon OSHA has conducted three scheduled inspections at the Boardman plant since 2002, Mesaros said. No violations were found in April 2006. A serious violation related to machine guards was reported in a July 2006 inspection that resulted in a $780 penalty. In September 2007, the company received an "other than serious" citation. Violations are listed as serious or other than serious, Mesaros said. Stock
I did print a list of welders last night to call today then I can stand back. The Miller is 10,000 watts and they did say it will run on two phase also. Guess I'll get the model today and a picture. I guess I can email it to welder to get a idea and if they want to do the job without lugging it around.
Welding a air compressor tank: I'm not sure a 3-phase motor will run on 2-phase (I think 2-phase is some times called "Split-phase" ??). Any way... it seems complicated... ... not unusual for me... LOL Here's 2 good links to enhance the confusion level... LOL http://www.engineeringtalk.com/news/abb/abb258.html http://en.wikipedia.org/wiki/Split_phase_electric_power I'm going to "favoritetize" the first link... seems to be pretty interesting... Call the Miller place again and make sure your machine will put out 3-phase . Or, see if the motor will work on 2-phase. OCR...
I was told the motor will run on 2 phase. I didn't look at the model number of what I have yesterday but it is in the catalog when I looked few months ago. I guess that wil tell me in the catalog if it work. Thanks for your help.
Welding a air compressor tank: Speedpup, I just got back from plowing snow, so I thought I'd check up on the new threads, and I noticed something rather peculiar... Look at the Grainger link you posted, it shows "Grainger/items/1WD58" . Now look at the link that 25c copied and quoted from your post. It shows "Grainger/items/4XA61" ... how did that happen??? LOL You have two different items that you're looking at, or I'm looking at, or somebody's looking at... :cool2 If you have Item # 4XA61... it has a 1-phase motor on it... :thumbsup Basically the same compressors, just different motors... OCR...
Dwan pointed out what I was going to say 200 PSI doesn't sound like a lot but that is 200 PSi on ONE saqare inch of area if you calculate how much area the tank has (the actual metal surface area) you get big numbers very quick. I'm a decent welder and I wont try welding on a pressure vessel. Find someone that Really knows what they're doing or you could be towing around a bomb... literally. For an example check out that Mythbusters episode where they actually shot a water heater a hundred or two feet in the air, very dangerous stuff.
I was just really showing the tank to give people an idea. I won't know till I look at it again and see what model it really is. I'll take a picture if the crack too and post it.
Crack pictures [img=http://img18.imageshack.us/img18/3256/crack2h.th.jpg] [img=http://img7.imageshack.us/img7/193/crack3a.th.jpg] Looks like it is three phase only? Wonder if my Miller welder / generator will run it? I have Bobcat Miller. [img=http://img6.imageshack.us/img6/7078/modelnumberwiring.th.jpg] ....
I know of a incident that happened with a portable air tank,some refer to them as a pig. The little air tank that you put air in and walk out and blow up a tire. Well it had a leak,someone welded it,the tank was used several times,until ! the last time,It blew the investigation revealed that it only had 120 to 125 psi. It almost decapatated the man next to it,and broke the legs of the man carrying it. Undisclosed settlement,the guy that welded it lost everything. Charged with involentary manslaughter.
Well after all this I am told I need 80 amps to start it up that I don't have.
After seeing the pictures of the crack, it doesn't look so simple to fix. If the crack extends under the motor mounting bracket, one would have to cut off the motor mount before welding up the crack. Obviously that creates other problems and increases the size and challenge of the repair job. Would you trust the tank when under pressure after extensive cutting and welding? Whoever you got this from likely made the correct decision when they decided not to repair it. I suppose you could always repair it and then sue the seller when it blows up, if you are still alive.:badidea Maybe you can put the motor and compressor onto another tank - that is if you can supply the three phase power. Three phase motors are a real pain in the **** To rewind motors or to buy phase converters are deal breakers.
Welding a air compressor tank: Dang... looks like you're running out of options... as far as keeping it a freebee. You could replace the 5 horse 3-phase with a 5 horse single-phase... but I think a 5 horse single-phase motor is a lot more money??... :beatsme And you have that crack you have to deal with... You do have a good compressor though.... Not sure which way I'd go?? OCR On edit: "You do have a good compressor though." Maybe not?? If something is wrong with the compressor... it might have vibrated enough to cause the crack in the first place???
well I thought I finally got something for nothing except for a punch in the face. Guess I'll ebay it or give it away:beatsme
80 amps is way to high a figure for a 5 horse compressor - check tag on motor
let me know what you think? http://img6.imageshack.us/my.php?image=modelnumberwiring.jpg I just sent it to an electrician I know. Thanks!
If I am reading that tag right it says Max. circuit size 80amps- Min, 31Amps For your application would it be practical to drive air pump from welder motor? You could get some black large black iron pipe, put side by side would serve as mounting frame ,as well as air tank. you would need some sort of speed reduction- Trans, belts,etc. Also a continuous run unloader- some can be set either way This would solve 3 phase -bad tank Miller sold a lg diesel welder with a vane comp. attached yrs ago(may still)
Thanks for the help but it is not worth all that trouble for me.
speedpup you are right ,its probably a vibration crack. not rusted out .take it to a certified welder its an easy fix .I am certified and have welded a few your bigger problem will be purchasing an inverter to go from three phase to single.I have plumbed a ball valve to the bottom of my tank so i can just kick it with my foot to bleed off the air pressure each time im finished with the air compresser. your compresser should cut off at approx 120 psi good luck chuck jacobs
SPEEDPUP i use a miller aead 200le 200 amp welder, it has a 30 amp recepticle on the front. that should be plenty to run an air compresser
Chuck I have a Miller Bobcat 225 9500 constant 10,000 surge. Thanks any tips where to buy an inverter to go from three phase to single? I'll try google too. The motor is 7.5 HP 3 phase. Thanks Chuck. I can see in the crack it is not rusted. found this http://www.temcophaseconverter.com/three-phase-converters.html Not really sure what I am looking at or need. found this Typical Equipment Power Usage -------------------------------------------------------------------------------- Bobcats and Trailblazers will easily start and run the following equipment: Farm Equipment Starting Watts Running Watts Barn cleaner (5HP) 11,600 3000 Silo unloader (5HP) 12,200 4300 Portable Conveyer (½ HP) 3400 1000 Milker (5HP) 10,500 2800 Contractor Tools Hand drill (½ in) 600 600 Circular saw (8¼ in) 1400 1400 Air compressor (1¼ in) 8200 2200 What is 1-1/4" the piston size of the compressor? Flood lights (vapor) 1250 1000 Household Refrigerator/freezer 2200 700 Sump pump 1300 800 Welding/Cutting Equipment Millermatic®212 MIG welder, 30-210 A, 230 V 6500 6500 Spectrum®625 30 A, 230V, ½ in cut 6900 6900
Welding a air compressor tank: Every time I open that ImageShack web page, it greets me with... Hey Dummy !! I wonder how they found out???........ :lmao Thought you were going to give her up, Speedpup? Look here if you think you might want to change motors... from 3-pahse to single-phase. http://www.nextag.com/7-5HP-Leeson-Single-545651712/prices-html Looks like the three Phase Converter is about the same price, which might be the way to go... you should always be able to run a 3-phase device, if the issue comes up again. Anyway, again... good luck, OCR...
If you are considering a phase convertor make sure that it is not the type (static) that results in horsepower loss. Your compressor may not work right if the motor loses 1/4 or 1/3 of its horsepower.
I have an eletric motor guy I use for my masonry saws he can tell me my options and do what is required. Fist I'll see how much to have it welded. Then tackle the electric end. Thanks all for all the time and help!