I had a good chat to the man who does the insurance inspection on our compressors at work... he used a thickness tester and a camera to check them out every year. The big one was made in the 60's . He said they will normally blow a pin hole in the tank when corrode badly and very rarely explode.. Only after people have tried to repair the tanks by welding up the pin holes and of patching in new steel and drain fittings do they generally become dangerous due to the heat from welding and the stresses caused by it..
the guy on youtube that had his explode did so for the very reason you mentioned, it rusted out on the bottom, started leaking and he welded a patch over it, the air compressor ended up exploding..
Black coating you called protective coating is really just mill scale. It’s iron oxide that bonds to the surface of hot rolled steel. It protects if from atmospheric corrosion.
I bought an old one, a Clark Tiger or something. It was £50. I probably spent about the same replacing valves and stuff. It vibrated so much when it was charging the tank it would roll across the floor. The wheels had fallen off so it achieved decent movement purely by vibration. I sold it for about 100, bought an electric nailer. Which has since broken. Now I use a hammer and nails.
"HYD" refers to hydrostatic pressure testing. They fill the tank with water and pressurize it to 250 PSI. They use water so if the tank ruptures, there is no explosive release of pressure.
I rebuild air compressors here in the mountains of Colorado. My preferred method is to take all of the fittings out of a pressure tank, and look inside it. Light it up from inside with a very small bulb that will fit into any one of the half inch or 3/4 inch holes. Then drop an assortment of bolts and nuts inside it, with a solvent like lacquer thinner or just about any other type of a solvent fluid. Rattle it around as long as you can stand it until your arms get sore, and then dump everything out, pull the hardware out with a magnet. Then the tank will look much cleaner inside, if there was any rust. Colorado is west of the hundredth Meridian in the US, so it is very dry here. Relative humidity is very low compared to the eastern part of the US. So rust as you see, in the British Isles, is simply non-existent here in the West. Lucky for us. And then if I really want to get carried away I will pour paint inside it, the best rust resistant oil resistant paint that I can find, and slosh it around to make sure all of the bottom of the tank is completely covered. Let it dry, run some air into it and leave one of the holes open, so that the air can get out, to help it dry quickly. Assemble everything, and you have an essentially brand new air tank.
I was thinking do same thing. But thinking a bit I decided it doesn't worth it. You have many mistakes in your thinking. You can't clean all the rust from inside. No matter what you do the metal will have spots covered with rust. Did you see this guys was grinding and he still has had some dots covered with rust.If you paint over with some rust guard paint it ideally should soak till the metal through the rust to avoid further corrosion. That's unlikely to happen. So eventually it will continue to rust in some bad areas. The best you can do is put it in a cage run test to max possible pressure and then use regulator to reduce max pressure so that it does cut of earlier than the pressure you have tested. I've made decision to go cage route as cage needed anyway for the case if I get a faulty tank.
@@GosforthHandyman Is it not dangerous to use grinding discs for cutting and cutting discs for grinding? I’m a complete novice and this is a genuine question not a criticism.
@@markharrisllb you certainly shouldn't use a cutting disc for grinding, the disc isn't designed to take the side loading. Cutting with a grinding disc is slow because your removing more metal than you need but no real reason why you shouldn't.
@@markharrisllb Exactly what David Quirk said. Cutting discs are thin and meant to remove as little metal as possible in order to make a cut. Grinding discs are thick and are used for material removal, as opposed to making cuts. The thin discs are prone to explosion if too much pressure parallel to the axis and can be very dangerous in that situation. Be careful in general.
Functionally operates just as it should th-cam.com/users/postUgkxiiMg_x4gIWeXMWfBnDdRnME4qJUAva4w holds pressure perfectly when not in use. Glad one of the other reviews pointed out that the bottom pressure release valve was open; thought it was defective at first.
I purchased a 2nd hand air compressor that was in "good condition" from an auction. I was shocked to find that it was 1/3 full of water. You just never know how the last owner treated it. I was able to pull it to bits, clean and inspect the tank visually and hydrostatic pressure test it. I was happy to keep using it. However during transport the water with iron particles contaminated the high pressure line from the compressor pump and the non-return valve would get dirty and not seal. I was able to clean these lines and fix the problem. However had I known that original state of it, there is no way I would have purchased it.
Appreciate that you took the time to diagnose, film, and put it out to inform us. ** never weld a tank, they are heat treated after all welding is complete so the tank can "breath" like a lung with pressure changes.
@@fredhinck9685 Heat treatment is often applied to relieve any internal stresses within the metal caused by the welding process. Done after all attachments are welded.
This one would have probably lasted longer than your new one! Quality of these things now, is very poor. I bet your new tank was not that thick. Thanks for your video. It was very interesting.
Water is a solvent, especially when it's full of atmospheric particles or debris suspended in your workshop air. Over enough compression cycles and repeated condensation, that layer would be eaten through no matter what, faster than you would imagine. Believe it or not aluminum would be even worse due to its reactivity. And while yes, that would lead to eventual tank compromise, what would happen first is that layer would break down into little chunks in particulate that would ruin your air tools paint, and anything else you're blowing the air at. It seems like an obvious and logical thing to do - but that's a hint somebody else already thought of it and there's a reason why it's not done.
@@sklikizos Well to be fair, more often than not these days that "reason" is money and not wanting to spend any more of it than they absolutely have to to make a product.
Interesting video . My compressor is 20 years old . Must admit when not in use . The drain is left open . The motor and pump on yours has still got life . Both could have potentially been refurbished and built onto a new tank . Cool video
When I score a compressor with a questionable tank I slice off the mounting deck using a 6" thin kerf cutoff wheel. I also slice off the wheel mounts with the wheels if they are any good. Then if the tank seems worthy I slice the tank horizontally and use the halves for other purposes. Large tanks sell or barter easily to people welding pig cookers so nothing is wasted. What few remember is the motor/pump deck is mounted to the tank for convenience and some compressors came with NO tank from the factory (I've an old military example which works well). You can and I do run compressors separate from tanks and that makes large units easy to move. Thanks to cheap consumer junk integral pump/motor units I regularly find good tanks (I use a USB borescope with my shop computer so I've a large display) to use with frequently superior old pumps. I crack all my drain valves on installation since I don't need to store air between uses. I've no condensation buildup that's not promptly blown out at first start. Discarded systems rarely failed as a system. This goes for computers, compressors, cars, trucks, and much more. I dont prettify anything I repair or rearrange, I do ensure it's safe to use. Note that just a nice coat of paint does NOT restore machinery. Overhauls do because the innards are what functionally matters. Want a ten horse and can't afford the wiring etc? Two fives are a common commercial solution and I only run a single when not blasting.
I've got a Kellog American Compressor, the date on the ASME certification tag says 1940, shell thickness is 13/64inch. I use it nearly every day and keep her filled to 140psi at all times! I certainly don't stand next to it and watch it fill up though. It's kept in a side compartment of my shed, so hopefully the chip board and drywall will keep the shrapnel contained, should it ever let loose.
I cut metal all the time with a grinder, but I use a really thin diamond coated metal cutting blade from Lennox. That super-wide disk ground away about 6X as much metal as the blade I use. I also use gloves, goggles AND a face shield. Yes, that is two things to keep crap out of my eyes. I learned the hard way the value of a second level of protection for your eyes. Kind of like still using a condom even if she says that she is on the pill. Better safe than sorry.
Hyd will be with water. It’s much safer to test with water a pressure as there is much less stored energy. If we are testing with air on site we have to set up exclusion zone and all sorts of things. If we test with a fluid we don’t have to.
@@KiboTennis This might be proof that it isn't, surely, plus the water drains out of their sinks the wrong way round, but I guess the Kangaroo puppies would fall out their mum's pouch, so much contradicting evidence!
All air receivers are prone to condensation inside, which causes rusting from the inside (which cannot be detected from the outside)... At the end of the day the water should be drained via a tap at the bottom, preferably with the cylinder still under pressure to blow out the water... It should then be left open until the compressor is next used. All cylinders should be visually checked on a regular basis (a cheap video camera can be used inside the tank), and pressure tested at least once every two years, using water (not air) and a boiler test pump to 2X (or better still 3X) the normal working pressure... Any weaknesses , or thin spots, will then show as water leaks - if you tried the same test using air the cylinder coud explode (as seen in another YT video, caught on security camera)... Compressed air has immense stored energy, whereas water is virtually impossible to compress. so doesn't store energy.. Having said that I have an old riveted cylinder, so at least pre WW2 - I know it has rusted through as it sits on a block of wood with a piece of rubber between - it blows off at about 50psi..... I've just bought a newer replacement, and will pressure test that before I use it.... The old cylinder will become a garden BBQ or fire-pit....
I used a compressor and nail gun in a loft conversion once and forgot to turn it off after work. It started up at 2am and scared the shit out of the clients living there😂 don’t use it now after getting a Ryobi battery nailer
Andy, watched the video this morning and this afternoon when running up my 20 year old Axminster compressor a rusty pin hole blew out , no explosion just a lot of hissing, time for a new one I think
I have been in the air compressor business since 1979 I wish people would realize that an air tank is actually stored energy! and it is so important to drain the tank regularly. and never buy a compressor that does not have a certification tag ( the welded 3x5 ") metal tag on the tank, this tank was a certified tank and still had great damage from neglect. good video. THE Compressor Guru
This video is an eye opener for me. I own 2 "aged" compressors I've been using off and on lately. They were given to me to use at my shop. I've repaired both and thought they were in good condition. Well, I'm going to re-think if I should consider scrapping them. I viewed your video with attention to details you explained very well. Thank You. Regards, Bert from 'Bama USA
I believe that is leaded steel; similar to that used in automobile fuel tanks - it is non-sparking. OSHA in the US had a case they thought a leaking o-ring or seal let too much compressor oil into the tank and the oil mist ignited when the compressor heated up in normal operation. So a fuel type explosion, not just rusty tank. 30 weight motor oil not particularly flammable unless it is in an aerosol
hyd probably stands for hydro, usual way of testing pressure vesels - it gets filled with water not air, that way if vesel fails it is much less dangerous
The condition of this tank is really not that bad given its age. The thing to have done would be to have it hydraulically tested "HYD" is hydraulically tested to 225psi. I am lucky that I have a pressure vessel tester at the bottom of my road. I may be wrong, but I believe a pressure vessel such as this should be re-tested after it reaches 10 years of age... but it does depend on the size of the vessel and what use/working pressure it is being put to.
I recently heard about a guy’s compressor exploding & nearly destroying everything within 6 ft of it. I was not aware this was even a problem, but clearly, it is. This begs the question as to why compressor manufacturers don’t heavily treat the inside of these tanks or use a liner of some sort? Have there not been any liability lawsuits from people injured or damage to property? One would think there would be a standard of time or use to go by…
I used to sell these (at Machine Mart) if you have a compressor ten years past the test date stamped on the tank, be careful, they should be tested. Or you can buy new tanks separately, these old pumps and motors are far more reliable than the new ones. We would scrap loads of compressors with burnt out motors or seized pumps (most only 2,3 years old) so speak nicely to the staff.
Just watched two vids on someone who's compressor exploded a week ago. The tank ripped apart like a bomb and the guy is lucky to be alive. Great vid and appreciate the advice and inspection tips.
Nice tank 👍 Well designed and built. The welded seam is in great shape. This tank would likely fail via pinholes on the bottom centerline. Yes, horizontal tanks get a fair amount of rust on the top.
The one you have there is from an old range which has what we used to call a ‘T-pump’. That’s a pre-1990 machine and the pump will be mainly cast iron. Around ‘90-‘91 these gave way to a cheaper, lighter Italian-made (Fini) pump which was nowhere near as durable - especially the valve plate. A lot of the larger air receivers were made by Rednal Pneumatics in Shropshire and they were proper quality. The Rednal ones usually carried the name etc on the end. 50/60 litres was the transition between Rednal tanks and imported ones. If I remember right, petrol portables used Rednal tanks but electrics used imports - definitely lesser quality!!
I have a similar one from 1962! I have been watching some tube videos and have decided not to use it anymore though it still works fine. I have drained the tank often but very dry here,not much humidity just the water created from compressing the air. I think I will cut mine open as well.
I just took my compressor apart and sent the tank to compressor heaven as well. I bought it new in 1987. Speedaire compressor on a Melben tank made in Leitchfield KY, USA. Man that thing pumped a lot of air over the years. So I got about 36 years out of the tank. It wound up with a pin hole in the bottom of its 30 gal vertical tank. After debating on trying to fix the tank, and seeing so many people on the TH-cam say not to do it, I took their advise and condemned it. I bought a used 60 gal vertical tank compressor that has a stamp on the tank plate saying 2018. Supposedly it hasn't been used in a year, so it should only have about 5 years on it. It was in an unconditioned garage, so it wasn't used during the cold Southern Ontario winters here because compressor condensate freezes things up. I'm going to try and stick a camera of sorts into the tank and check the rust, and possibly try to rust proof it with something. I might make a video of that and post it on my channel. Thanks for your video, it was interesting to see the rust in an old tank.
That was interesting, I own a stand up compressor, I keep the drain valve open at all times. I was wondering if the stand up type would be better because the condensation would drain out better.
These are better for several reasons. Water collects mostly in the lower dome. The domes are stronger than the cylinder section. The dome weld is far away from the water. Any failures should occur at the bottom, and resulting thrust should be vertical (like a rocket taking off). The compressor weight, plus the anchor bolt strength will likely resist that thrust (I've done the calculations). Also, with a vertical tank, the air discharge port is further from the water on the bottom, so you get much less water in the air. I run spray guns, and water is a huge issue. Not great for your aluminum turbine tools, either.
Hydro testing is worthless on a rusted tank, they can easily hold the testing pressure but if there is rust inside and the compressor is back in use water will stay on that rust longer like a paper towel holds onto water and it will make it rust 10 times faster.
It might hold pressure but that’s the problem. You will never be able to predict when the walls of the tank have a thin spot from corrosion/rust. The more resistance to a burst, the more pressure it will take to burst, and thus the more explosive that burst will be. Take a bicycle inner tube and fill it till it pops. It’s a pretty strong pop. And that’s with thin rubber. Now do the same with an air compressor tank. What pressure will be too much? 80psi? 100? 120? 140? Care to try it out? Check out pics and videos of the results and you will not want to push your luck. One guy had massive damage to his garage from the air pressure. His garage door was even open, and it knocked it off the tracks, knocked the door rail anchors out of the concrete, broke every window, pushed out the window frame closest to the compressor, and basically knocked down or broke anything with any cross section in the garage. His wife was in the house and she said it shook the ground as much as any earthquake she had ever felt. If anyone had been adjacent to the compressor it would have surely killed them. The tank shot straight up to the ceiling/garage door tracks/door btw. Knowing that and seeing the damage was shocking.
@@andrewhigdon8346 That's why you test tanks with water rather than air. Water doesn't compress, so if the tank does pop, all you get is a bit of a splash rather than an explosion. And you test it to well above its rated pressure to make sure it won't fail under normal operating conditions. I'm not 100% confident I'd try this myself but I've seen it done and it seems reasonable.
The HD stamp is hydro test , in order for any tank to be allowed as a compressor it has to be tested using water or glycol . that was my job when I worked on oil seperators, we would have to fill the tank from the bottom (if done from the top you will have air and will not be able to test) we had to test 1 1/2 times the working pressure which is where the 225 stamp comes in. It's a max psi of 150 so 150 +75 =225 . it has to hold that pressure for 15 min. And all welds are checked for any leak. By law anything over 110 psi has to be filled with liquid so that if there is a stress crack , or a faulty weld you take a quick shower otherwise goid chance your not going to be around for any other test as it will explode like a grenade shooting metal into whoever is near the tank. If a tank gets to thin from water, rust you can cut a section out and basically put a new piece in a band aid . the second serial no. Is logged into a federal data base which is a paper trailall the numbers on that tag will tell you where that steel waa milled and when , who welded on that tank , who pressure tested that tank and who did the final inspection giving that tank a pass to become a compressor. So all them tags and numbers are it's birth certificate if you will.
I think i depends on how will you take care of it. If you put a water separator / dryer in right after the pump. It could last for a very long time. That is what I am planing on doing when I get my big compressor.
Interesting to see the condition of the inside of the tank. In the future you could remove the fixtures, hook up a pressure gauge, fill it with water then hook up a pressure washer to hydro test it yourself. Also you can get a boroscope camera that hooks up to your phone for less than $20.
I would have thought an explosion most unlikely, one of those pits would get so weak it would just give way and you'd hear a nice hissing. Also why would it crack, unless you'd damaged the outside severely somehow, since it has been clearly ok for 37 years? Elf and safety gone mad sir!
37 is nothing we have two 250 litre ones the youngest one is 55 years old. The other is much older. Both pass inspection every year. I was just thinking how sad it was to cut this up. What a waste. Out side in a shelter that would contain it if they popped it wouldn’t be a problem anyway.
Yeah I think most explosions would be due to the pressure regulator or pressure relief valve not working properly combined with a rusty old tank. Oh hold on... 😂👍
@@GosforthHandyman ive had tanks rist through they hissed i welded the hole shut to get the job done and didn't remember till the next year when another spot rusted through lol
@@timjohnson6864 Then watch this, and think again..... l.facebook.com/l.php?u=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DKVP_A7eGYxw%26feature%3Demb_logo%26fbclid%3DIwAR08LhsBqi-LhRGkrIcYJCxBlpxMp9UNZ7JNoyTOGGeL7b06-R-P80GhC48&h=AT1-eecFdf5AqjejmEptqbJ_rCO_78f9XJXGmlphoi4TA_xm-7PqRsmYxuoq_C0SceRo8pN9ntij7LQKxZoqdiFpjIomxUrZ1tEDltvGNrxywXfTcnAkpGEIn0ldutSmKx41_QC0JVsgrn0Y
I did have a tank rust out on me and it didn't explode. It was the small 10/15L type and was about 15 years old. What actually happened was.. as you show.. a ribbon of rust pits or holes along the bottom inside of the cylinder and evenually one breaks through so you get a small whistle and obviously it doesn't hold the full pressure any more.. The first hole is probably only a pin hole but does make you aware... so you explore and quickly find the offending area.. You think about repairs.. bit of welding (can't do that..) an epoxy patch.. (nah..) screw a plate of metal over the area.. (probably the best option.. ) Have a cuppa tea.. think.. Snip off any extraneous useful looking bits and kick it to the curb.. Hello Machine mart.. whatchgotonoffer..?
At work I took over responsibility for an at least ten year old clark whisssper all in one compressor. I could hear water sloshing about inside the tank. I removed the drain tap and strangely no air or water came out. on further investigation I found that although the drain threaded boss had been welded to the tank the tank had not been drilled by the manufacturer. I returned the unit to Clarks R & D dept. it came back a few weeks later with a hole drilled through the drain boss so the drain tap worked. strangely enough it failed completely a few weeks later. I wondered how many of that batch hadn't had the drain hole drilled through at manufacture.
I worked for a company that used air compressors to operate gas/air pumps, and the compressors had to be serviced regularly ie change pressure valves,air filters etc and replaced every ten years.So you got good service from your old one, but definitely time for a new one.
Large ones in industrial plant I have seen them up to 60 years old and still in use. They get hydro tested every year during shutdown (regulations say every 5 years, but they are figuring as the plant is being shut down might as well do it as well) as to replace them will mean dismantling large chunks of buildings and removing plant and roof to get cranes in. Tossing after 10 years on a small one is possible, as the test after that time, and fixing it, probably is approaching the cost of a new one anyway. But on large units you will want those parts to last a long time, so regular service of the compressors, change oil regular and so on.
It really depends on how well the tank has been taken care of and the quality. My dad‘s old speed air lasted 30 years and it still works. I’m just afraid to use it anymore and it has not been taken care of very well to be quite honest, I think you just comes down to quality in this case in this case
You could have made a small forge of the tank if you're into that sort of things. Pask Makes did a forge pig to heat treat steel to make his own tools etc. The motor is also still usable to make other machinery.
For anybody interested, the formula used to calculate the hoop stress in a cylinder, (the most heavily stressed part being the parallel sided portion) is PD/2T, i.e. internal pressure x diameter divided by twice the wall thickness. With deep drawn cylinders the burst failure is normally a straight line down the longitudinal axis; with welded (rusty) tanks it can be more chaotic but it is surprising what decent steel can withstand. Even the humble 15mm copper pipe can theoretically withstand more than 20 bar of internal pressure, though I don't think I'd like to cycle it too often!!
I don't know why more compressors don't come with a 1/4 turn valve for draining. I have a 1/4turn on my big compressor and a screw type on my small compressor. The big one gets drained everytime I use it, the small one gets drained about once a year.
I have a soviet compressor, an old man used it für 40 yrs and i borrowed it für one day and end of the day the tank started to leake air at the welds, turned out its lifespan was exacly 40 yrs.
This definitely has me thinking about my compressor. It is at least 12 years old and has a broken wheel on it that I have been meaning to repair but maybe it isn’t even worth it. I didn’t even think that it would have a short life span.
You could have used this as a secondary air tank for your new compressor Andy, You get more air flow then, just fill a check valve, look up on YT about it
That’s actually pretty thick tank in comparison to the small twin tank units the real shame is how much longer that compressor would have worked if the manufacturer had spent even a few seconds to spray some self etching weld through primer inside it prior to it being welded together. My next tank have powder coating inside - u can’t expect bar steel to survive
Yes that is plain hot rolled steel scale, if they had at least done an acid etch on the inside after welding, and a quick thin electrogalvanise coating on the whole unit, followed by a bake to get the hydrogen out, it would last a really long time, or just have a sacrificial anode rod on the bottom that you can unscrew and replace every few years.
Powder coating acts as a scab at first penetration then traps moisture. I've seen it on many pieces of coated equipment bought at auction. Consider self-etching (powder coat is not) paint/primer instead.
Great video. Pretty scary when you think about it. I’m not sure I even trust brand new tanks considering the quality of manufacture on everything nowadays. I’m going to make sure mine is far enough away from me in a worst case scenario.
Great video, very informative! If that's used at home, there's no regulation (other than the usual CE Marking for supply) that mandates any regular inspection. But if it's used in a workplace, and the volume x pressure is more than 250 Bar Litres (excluding the 24 Litre, 10 Bar "Hobby Compressors"), it would legally need a WSE (Written Scheme of Examination) under PSSR (Pressure Systems Safety Regulation):2000, which would dictate (certified by a "competent person", based on a risk assessment) what degree of inspection (typically ultrasonic thickness test for the receiver and a pressure test of the PRV and Gauges against a calibrated gauge). The receivers ("pressure vessels") are always supplied against a design code (should be stated on teh data plate!) which specifies the minimum design thickness, plus a corrosion allowance (EN 286-1 is typically 2mm + 0.5mm for steel, but older codes had a greater thickness). That one was probably the older BS 5169, possibly with 3mm + 0.75mm corrosion allowance. Life expectancy will depend on how often the condensate is drained from the receiver and often it's the compressor (especially if not regularly maintained) that limits the life... Modern industrial compressors tend to be coupled with an automatic timed or zero-loss drain, so you don't have to remember to do it manually.
Its old machinery, of course it still works. No PCB board, no pre-installed failures... Solid item. Personally, I have always been terrified of air compressors, as well as flammable gases . Worst of all, flammable compressed gases (propane tanks, butane cans) and I have always wondered why these aren't made of stainless steel, or at least coated internally with a paint or protectant to prevent rust... I mean, the inside is never touched by solids, it wouldnt degrade at all presumably...
@@coldblu357 I've always wondered how moisture gets out of a compressor. You drain all the water out but the humidity stays in there unless it somehow evaporates out of that tiny valve hole. You may not have standing water but you'd have to leave the tank out in the sun for quite a long time for it to actually dry out inside.
@@randywl8925 When the air gets pumped in hot it creates moisture. Some people coil the feed line from the pump to the tank or add an air cooler in line to help with moisture. I learned it from the guys that paint, they know all the cool tricks.
3:14 Hydraulic test. it's a test where you add water under pressure and see until where it can hold that pressure. I've done it in a boiler with a manual pump and let me tell you it's not a small feat. Generally the hydraulic test is done @ 200%- 250% the real working pressure
The correct way to do this would have been to perform a 'house' hydraulic test first, then open it up and see how the steel was, thus establishing at least some correlation. As it is we have no actual information, though given the 2.4mm residual thickness I agree with a prior commenter, it would probably last about as much at is already has at least.
Hyd. test is probably hydrostatic test pressure. Filled with water and pressurised. I did this sort of testing as part of my fitter / machinist apprenticeship. Company manufactured flow control and safety release valves.
I think that small pressure tanks are supposed to be replaced after ten years from test date,in industrial and commercial use they have to inspected on a regular basis by a competent person like once a year, insurance companies will usually arrange this.
Actually I've done that, A mate got one a fair few years back and due to his own stupidity he ran it without oil, so he gave it to me to turn it into a bbq (I do the same with Gas Bottles) and the Aldi tank was in really decent condition with the wall thickness around 3mm I believe, which is the same for calor gas bottles.
Hyd. stands for hydraulic. As other comments have said, liquid (hydraulic) testing is much safer than gas (air) testing 'cos if it fails it won't explode - but you might get wet!
HYD means that they filled it with liquid or hydraulically tested it to that pressure so that if the tank did let go it was with water or oil that is not compressible so their is no violent explosion. Just a mild pop of liquid that would startle you but not violently blow the windows out of your shed and send the tank through your roof They always test at higher pressure with liquid filling the tank. I have tested tanks using water and a grease gun to pressurize it.
I just adjusted my cut out down to 50 lbs, only doing tires occasionally. I don't need 150 lbs out of my old Craftsman. I guess I feel a bit safer, after seeing the explosion videos.
Why don't they line the inside where condensation begins. Or line the in side with stainless I don't know but anything might be better than a material that gets rusty you think.
In a commercial setting this tank would be classified as a pressure vessel subject to statutory inspection by a competent person. There’s so many small DIY / trade vessels it’s impractical to have them inspected as they should be. Most comments focused on a corrosion pit failing to a simple leak. That does happen and it has to be your luckiest day when you discover it. Very few suggested rupture of the vessel. This is the reason for statutory inspection. While industrial size vessels can destroy buildings, small vessels are used in the same room as the user. Personal injury is likely, so I would worry the growing and aging fleet of small cheap compressors is a growing risk. First, look at your use. If it’s running every day you should get serious about inspection, get an expert technician on board or become one as best you can. Less frequent use; be sure to drain fully after use, maybe open the vent plugs to dry the tank, peer into the vent holes looking for rust along the waterline per this video. Either way you won’t have the ultrasonic gear to properly inspect for wastage of the tank due to inevitable corrosion. Above all, don’t prolong the life of the vessel beyond a sensible period. Some of the ages quoted above are nuts, given the potential risk. Buy a new one as soon as you get any excuse.
I need to get a bore scope so can look inside mine. It's a 60 gallon Coleman I bought new in 2000 at CostCo. It only gets occasional use, but I live in a very wet and cold climate. It'll be interesting to see inside.
My Campbell Hausfield was purchased in 2000. It developed a pin hole leak in 2017 were the longitudinal weld meets the end bell weld. Tha autopsy revealed little rust were the pin hole developed but a heavy belt of rust along the bottom. The 13 gallon tank walls were only 3/32 inch metal.
You get a lot of condensation inside any pressure vessel. The shorthand life of a pressure vessel is ten years, then inspection is required... Most of us get complacent enough with gas bottles, so unfortunately air bottles seem to get ignored until something goes wrong.
Because standards have changed over the last half century, you just sacrificed a really well manufactured product for one that begins life at 1/8 the thickness. If you were worried about the state there ways to measure and determine metal thickness.
So true. I have an old Craftsman with a DeVilbiss tank, and an old Ingersoll Rand with (believe it or not) an Ingersoll Rand tank and a mag starter. Bought the Rand at Home Depot! The industrial brands are still good, just hella expensive. I don't think any of those guys (Schulz, et al.) make small portable units. Let me know if you see one. I'll recommend it.
Next time Hydo test, read the inspection label on tank for max psi. Fill tank full of water, install 2x psi gauge, hook pressure wash wand to tank and pressuruze tank to 2x rating.
I've seen comments from people who did that and it was ineffective. High end brands, like Schulz, powder coat the tank inner walls at the factory. Don't worry about your Makita. The drain water will be rusty from day one. I have a 30 year old Ingersoll Rand (U.S. made back then). It's drain water appearance has been consistent over the decades.
No Andy... it isn't heavier... we're _older_ now :^) Even draining regularly I won't keep compressors around forever. Just not worth the risk over time. EDIT: Can't find it now, but looking at compressors recently I recall one of them said to replace after 5 years of service. They have expiry dates on the tags now like gas cylinders.
In Europe there is no official age limit, however commercially used compressors have to be checked by hydro test every 10 years. Tanks which are coated inside can withstand decades without corrosion, you can recognize it if the water you drain is white, or rusty. Big tanks here have a hole which can be opened for seeing inside the tank.
Just found mine has recently gone, got a hairline crack at the top where the motor bracket welds to the tank is. I guess the motor vibration added to that. I picked it up second hand around 8-9 years ago, didnt know the history of it but have been meaning to replace it as whenever i drain it, rusty coloured water. Took the motor and fittings off it, and been thinking about converting a gas bottle. But will probably end up buying a brand new one. Think i might cut the remains of mine open now, see how bad it is.
I have an uncle who build his own compressor with a fridge engine or motor (I'm French so sorry for bad English). And I think the tank was a large scuba tank.
I dont think many people realise the danger of a compressed air tank or how they can be safely pressure checked. Hydro testing is a safe way to check the soundness of an air tank. Water wont explode if a seam seperates it just splits open and the water drains out.... So if you fill your compressor tank with water and have a way to overpressure the vessel, thats how its done. I usually check my tanks at 100 to 150 percent over rated pressure.
I found your video most interesting as I have exactly the same compressor which I purchased from Machine Mart in 1983 - it has the same datte of test etc. It has served me well and continues to do so never missing a beat they were made in Italy as was my MIG welder. Everything seems to be made in China now.
Just before you start cutting is where you hope it was actually dead... extremely interesting to see just what happens in there and how well the airmaster compressors were made. But I am now thinking about the old one I just replaced and thinking I should recycle it.
![BOWKYLION - วิงวอน (ex-change) [Official MV]](http://i.ytimg.com/vi/cLdnZWDaO-w/mqdefault.jpg)
I had a good chat to the man who does the insurance inspection on our compressors at work... he used a thickness tester and a camera to check them out every year. The big one was made in the 60's . He said they will normally blow a pin hole in the tank when corrode badly and very rarely explode.. Only after people have tried to repair the tanks by welding up the pin holes and of patching in new steel and drain fittings do they generally become dangerous due to the heat from welding and the stresses caused by it..
Thats true for the old massive tanks. New ones are thin sheet metal that will explode without much warning.
thats what inspection guy at work told me to
@@derektaylor2941So you’re saying don’t risk using an old compressor ?
This one exploded.. th-cam.com/video/W2LbTHfU5fQ/w-d-xo.html
the guy on youtube that had his explode did so for the very reason you mentioned, it rusted out on the bottom, started leaking and he welded a patch over it, the air compressor ended up exploding..
Black coating you called protective coating is really just mill scale. It’s iron oxide that bonds to the surface of hot rolled steel. It protects if from atmospheric corrosion.
I bought an old one, a Clark Tiger or something. It was £50. I probably spent about the same replacing valves and stuff. It vibrated so much when it was charging the tank it would roll across the floor. The wheels had fallen off so it achieved decent movement purely by vibration.
I sold it for about 100, bought an electric nailer. Which has since broken. Now I use a hammer and nails.
None of my tools break, largely because I don't use them very often😆
Sounds like evolution in reverse, lol.
"HYD" refers to hydrostatic pressure testing. They fill the tank with water and pressurize it to 250 PSI. They use water so if the tank ruptures, there is no explosive release of pressure.
Used to do this for a living. Built all sorts of tanks and I was lead inspector plug it and fill it.
Only ever had one explode, it sent the plug over a football field length through the shop and out the sheet metal wall it went.
Just like scuba tanks, they have t be "hydroed" on schedule
I rebuild air compressors here in the mountains of Colorado. My preferred method is to take all of the fittings out of a pressure tank, and look inside it. Light it up from inside with a very small bulb that will fit into any one of the half inch or 3/4 inch holes. Then drop an assortment of bolts and nuts inside it, with a solvent like lacquer thinner or just about any other type of a solvent fluid. Rattle it around as long as you can stand it until your arms get sore, and then dump everything out, pull the hardware out with a magnet. Then the tank will look much cleaner inside, if there was any rust. Colorado is west of the hundredth Meridian in the US, so it is very dry here. Relative humidity is very low compared to the eastern part of the US. So rust as you see, in the British Isles, is simply non-existent here in the West. Lucky for us. And then if I really want to get carried away I will pour paint inside it, the best rust resistant oil resistant paint that I can find, and slosh it around to make sure all of the bottom of the tank is completely covered. Let it dry, run some air into it and leave one of the holes open, so that the air can get out, to help it dry quickly. Assemble everything, and you have an essentially brand new air tank.
Though I have to add that it's still a good idea to have it pressure tested if your tank is more than ten or twenty years old.
I was thinking do same thing. But thinking a bit I decided it doesn't worth it. You have many mistakes in your thinking. You can't clean all the rust from inside. No matter what you do the metal will have spots covered with rust. Did you see this guys was grinding and he still has had some dots covered with rust.If you paint over with some rust guard paint it ideally should soak till the metal through the rust to avoid further corrosion. That's unlikely to happen. So eventually it will continue to rust in some bad areas. The best you can do is put it in a cage run test to max possible pressure and then use regulator to reduce max pressure so that it does cut of earlier than the pressure you have tested. I've made decision to go cage route as cage needed anyway for the case if I get a faulty tank.
Had you not got no cutting discs, hard work with the grinding disc you used to cut it open
Better sparks for the vid. You'll see I'm doing 45 degree grinding passes to try and thin the material a bit around the cut. 👍
@@GosforthHandyman Is it not dangerous to use grinding discs for cutting and cutting discs for grinding? I’m a complete novice and this is a genuine question not a criticism.
@@markharrisllb you certainly shouldn't use a cutting disc for grinding, the disc isn't designed to take the side loading. Cutting with a grinding disc is slow because your removing more metal than you need but no real reason why you shouldn't.
@@markharrisllb Exactly what David Quirk said. Cutting discs are thin and meant to remove as little metal as possible in order to make a cut. Grinding discs are thick and are used for material removal, as opposed to making cuts. The thin discs are prone to explosion if too much pressure parallel to the axis and can be very dangerous in that situation. Be careful in general.
Functionally operates just as it should th-cam.com/users/postUgkxiiMg_x4gIWeXMWfBnDdRnME4qJUAva4w holds pressure perfectly when not in use. Glad one of the other reviews pointed out that the bottom pressure release valve was open; thought it was defective at first.
I purchased a 2nd hand air compressor that was in "good condition" from an auction. I was shocked to find that it was 1/3 full of water. You just never know how the last owner treated it.
I was able to pull it to bits, clean and inspect the tank visually and hydrostatic pressure test it. I was happy to keep using it.
However during transport the water with iron particles contaminated the high pressure line from the compressor pump and the non-return valve would get dirty and not seal. I was able to clean these lines and fix the problem.
However had I known that original state of it, there is no way I would have purchased it.
It probably last longer without regular draining as corrosion needs air and water
Appreciate that you took the time to diagnose, film, and put it out to inform us.
** never weld a tank, they are heat treated after all welding is complete so the tank can "breath" like a lung with pressure changes.
Perhaps, i would think Hydrostatic test every few years would be a better way to operate.
Doubt very much the heat treating is done after the wheels and motor and pump supports are " WELDED " on.
@@fredhinck9685 Heat treatment is often applied to relieve any internal stresses within the metal caused by the welding process. Done after all attachments are welded.
This one would have probably lasted longer than your new one! Quality of these things now, is very poor. I bet your new tank was not that thick. Thanks for your video. It was very interesting.
I don't see why compressor tanks don't have some kind of coating inside either aluminum or stainless. Or some kind of rubber to help extend the life.
Water is a solvent, especially when it's full of atmospheric particles or debris suspended in your workshop air. Over enough compression cycles and repeated condensation, that layer would be eaten through no matter what, faster than you would imagine. Believe it or not aluminum would be even worse due to its reactivity. And while yes, that would lead to eventual tank compromise, what would happen first is that layer would break down into little chunks in particulate that would ruin your air tools paint, and anything else you're blowing the air at. It seems like an obvious and logical thing to do - but that's a hint somebody else already thought of it and there's a reason why it's not done.
@@sklikizos Well to be fair, more often than not these days that "reason" is money and not wanting to spend any more of it than they absolutely have to to make a product.
Interesting video . My compressor is 20 years old . Must admit when not in use . The drain is left open .
The motor and pump on yours has still got life .
Both could have potentially been refurbished and built onto a new tank .
Cool video
When I score a compressor with a questionable tank I slice off the mounting deck using a 6" thin kerf cutoff wheel. I also slice off the wheel mounts with the wheels if they are any good.
Then if the tank seems worthy I slice the tank horizontally and use the halves for other purposes. Large tanks sell or barter easily to people welding pig cookers so nothing is wasted.
What few remember is the motor/pump deck is mounted to the tank for convenience and some compressors came with NO tank from the factory (I've an old military example which works well). You can and I do run compressors separate from tanks and that makes large units easy to move. Thanks to cheap consumer junk integral pump/motor units I regularly find good tanks (I use a USB borescope with my shop computer so I've a large display) to use with frequently superior old pumps.
I crack all my drain valves on installation since I don't need to store air between uses. I've no condensation buildup that's not promptly blown out at first start.
Discarded systems rarely failed as a system. This goes for computers, compressors, cars, trucks, and much more. I dont prettify anything I repair or rearrange, I do ensure it's safe to use.
Note that just a nice coat of paint does NOT restore machinery. Overhauls do because the innards are what functionally matters.
Want a ten horse and can't afford the wiring etc? Two fives are a common commercial solution and I only run a single when not blasting.
I've got a Kellog American Compressor, the date on the ASME certification tag says 1940, shell thickness is 13/64inch. I use it nearly every day and keep her filled to 140psi at all times! I certainly don't stand next to it and watch it fill up though. It's kept in a side compartment of my shed, so hopefully the chip board and drywall will keep the shrapnel contained, should it ever let loose.
Good video but I have never seen anyone try and cut metal with a grinding disc like that.
Me neither
What i can to say
I cut metal all the time with a grinder, but I use a really thin diamond coated metal cutting blade from Lennox. That super-wide disk ground away about 6X as much metal as the blade I use. I also use gloves, goggles AND a face shield. Yes, that is two things to keep crap out of my eyes. I learned the hard way the value of a second level of protection for your eyes. Kind of like still using a condom even if she says that she is on the pill. Better safe than sorry.
Absolutely, talk about make work for yourself!!!!
Probably took hours to cut that open!!
Hyd will be with water. It’s much safer to test with water a pressure as there is much less stored energy. If we are testing with air on site we have to set up exclusion zone and all sorts of things. If we test with a fluid we don’t have to.
That corrosion on the top side of the tank obviously meant it was used in Australia at some point.
Superior Being why would that matter? The earth is flat. 😉
@@KiboTennis This might be proof that it isn't, surely, plus the water drains out of their sinks the wrong way round, but I guess the Kangaroo puppies would fall out their mum's pouch, so much contradicting evidence!
Kangaroos have joeys, not puppies!
Superior Being - 😆
@@samuelfellows6923 I realise now that that Kangaroo is carrying a Kangapotamoose calf, my bad!
All air receivers are prone to condensation inside, which causes rusting from the inside (which cannot be detected from the outside)... At the end of the day the water should be drained via a tap at the bottom, preferably with the cylinder still under pressure to blow out the water... It should then be left open until the compressor is next used. All cylinders should be visually checked on a regular basis (a cheap video camera can be used inside the tank), and pressure tested at least once every two years, using water (not air) and a boiler test pump to 2X (or better still 3X) the normal working pressure... Any weaknesses , or thin spots, will then show as water leaks - if you tried the same test using air the cylinder coud explode (as seen in another YT video, caught on security camera)... Compressed air has immense stored energy, whereas water is virtually impossible to compress. so doesn't store energy.. Having said that I have an old riveted cylinder, so at least pre WW2 - I know it has rusted through as it sits on a block of wood with a piece of rubber between - it blows off at about 50psi..... I've just bought a newer replacement, and will pressure test that before I use it.... The old cylinder will become a garden BBQ or fire-pit....
the top is where water drops settle when water accumulates inside
I used a compressor and nail gun in a loft conversion once and forgot to turn it off after work. It started up at 2am and scared the shit out of the clients living there😂 don’t use it now after getting a Ryobi battery nailer
🤣
😂😆
I can imagine that 🤣😂
Andy, watched the video this morning and this afternoon when running up my 20 year old Axminster compressor a rusty pin hole blew out , no explosion just a lot of hissing, time for a new one I think
Wow What timing. Your very lucky.
@@andrewhigdon8346 * you're
I have been in the air compressor business since 1979 I wish people would realize that an air tank is actually stored energy! and it is so important to drain the tank regularly. and never buy a compressor that does not have a certification tag ( the welded 3x5 ") metal tag on the tank, this tank was a certified tank and still had great damage from neglect. good video.
THE Compressor Guru
This video is an eye opener for me. I own 2 "aged" compressors I've been using off and on lately. They were given to me to use at my shop. I've repaired both and thought they were in good condition. Well, I'm going to re-think if I should consider scrapping them. I viewed your video with attention to details you explained very well. Thank You. Regards, Bert from 'Bama USA
I believe that is leaded steel; similar to that used in automobile fuel tanks - it is non-sparking. OSHA in the US had a case they thought a leaking o-ring or seal let too much compressor oil into the tank and the oil mist ignited when the compressor heated up in normal operation. So a fuel type explosion, not just rusty tank. 30 weight motor oil not particularly flammable unless it is in an aerosol
hyd probably stands for hydro, usual way of testing pressure vesels - it gets filled with water not air, that way if vesel fails it is much less dangerous
Davorin Ruševljan Hyd stands for hydraulic as in hydraulic test pressure
Thanks!
The condition of this tank is really not that bad given its age. The thing to have done would be to have it hydraulically tested "HYD" is hydraulically tested to 225psi. I am lucky that I have a pressure vessel tester at the bottom of my road. I may be wrong, but I believe a pressure vessel such as this should be re-tested after it reaches 10 years of age... but it does depend on the size of the vessel and what use/working pressure it is being put to.
i have one of those mine was never checked and after i saw another one explode,,,, i wont be using it in the house again!
I recently heard about a guy’s compressor exploding & nearly destroying everything within 6 ft of it. I was not aware this was even a problem, but clearly, it is. This begs the question as to why compressor manufacturers don’t heavily treat the inside of these tanks or use a liner of some sort? Have there not been any liability lawsuits from people injured or damage to property? One would think there would be a standard of time or use to go by…
I used to sell these (at Machine Mart) if you have a compressor ten years past the test date stamped on the tank, be careful, they should be tested.
Or you can buy new tanks separately, these old pumps and motors are far more reliable than the new ones. We would scrap loads of compressors with burnt out motors or seized pumps (most only 2,3 years old) so speak nicely to the staff.
Just watched two vids on someone who's compressor exploded a week ago. The tank ripped apart like a bomb and the guy is lucky to be alive. Great vid and appreciate the advice and inspection tips.
Nice tank 👍 Well designed and built. The welded seam is in great shape. This tank would likely fail via pinholes on the bottom centerline.
Yes, horizontal tanks get a fair amount of rust on the top.
The one you have there is from an old range which has what we used to call a ‘T-pump’. That’s a pre-1990 machine and the pump will be mainly cast iron. Around ‘90-‘91 these gave way to a cheaper, lighter Italian-made (Fini) pump which was nowhere near as durable - especially the valve plate.
A lot of the larger air receivers were made by Rednal Pneumatics in Shropshire and they were proper quality. The Rednal ones usually carried the name etc on the end.
50/60 litres was the transition between Rednal tanks and imported ones. If I remember right, petrol portables used Rednal tanks but electrics used imports - definitely lesser quality!!
I have a similar one from 1962! I have been watching some tube videos and have decided not to use it anymore though it still works fine. I have drained the tank often but very dry here,not much humidity just the water created from compressing the air. I think I will cut mine open as well.
A cut off wheel instead of a grinding disc cuts a LOT more efficiently
I just took my compressor apart and sent the tank to compressor heaven as well. I bought it new in 1987. Speedaire compressor on a Melben tank made in Leitchfield KY, USA. Man that thing pumped a lot of air over the years. So I got about 36 years out of the tank. It wound up with a pin hole in the bottom of its 30 gal vertical tank. After debating on trying to fix the tank, and seeing so many people on the TH-cam say not to do it, I took their advise and condemned it. I bought a used 60 gal vertical tank compressor that has a stamp on the tank plate saying 2018. Supposedly it hasn't been used in a year, so it should only have about 5 years on it. It was in an unconditioned garage, so it wasn't used during the cold Southern Ontario winters here because compressor condensate freezes things up. I'm going to try and stick a camera of sorts into the tank and check the rust, and possibly try to rust proof it with something. I might make a video of that and post it on my channel. Thanks for your video, it was interesting to see the rust in an old tank.
That was interesting, I own a stand up compressor, I keep the drain valve open at all times. I was wondering if the stand up type would be better because the condensation would drain out better.
These are better for several reasons. Water collects mostly in the lower dome. The domes are stronger than the cylinder section. The dome weld is far away from the water. Any failures should occur at the bottom, and resulting thrust should be vertical (like a rocket taking off). The compressor weight, plus the anchor bolt strength will likely resist that thrust (I've done the calculations).
Also, with a vertical tank, the air discharge port is further from the water on the bottom, so you get much less water in the air. I run spray guns, and water is a huge issue. Not great for your aluminum turbine tools, either.
If you depressurize the tank when not in use, you'll never have an issue. Significant rust only occurs at high pressures.
Thanks for all the information, good to know
Why would rust be pressure dependent?
@@MrKentaroMotoPI yes condensation forms from change in temperature
Hyd means that the tank was hydro pressure tested with water. This is the correct and only safe way to pressure test a tank.
Hydro testing is worthless on a rusted tank, they can easily hold the testing pressure but if there is rust inside and the compressor is back in use water will stay on that rust longer like a paper towel holds onto water and it will make it rust 10 times faster.
Hydraulic testing, fill with water and pressurize and see if it holds for a specific period of time.
It might hold pressure but that’s the problem. You will never be able to predict when the walls of the tank have a thin spot from corrosion/rust. The more resistance to a burst, the more pressure it will take to burst, and thus the more explosive that burst will be. Take a bicycle inner tube and fill it till it pops. It’s a pretty strong pop. And that’s with thin rubber. Now do the same with an air compressor tank. What pressure will be too much? 80psi? 100? 120? 140? Care to try it out? Check out pics and videos of the results and you will not want to push your luck. One guy had massive damage to his garage from the air pressure. His garage door was even open, and it knocked it off the tracks, knocked the door rail anchors out of the concrete, broke every window, pushed out the window frame closest to the compressor, and basically knocked down or broke anything with any cross section in the garage. His wife was in the house and she said it shook the ground as much as any earthquake she had ever felt. If anyone had been adjacent to the compressor it would have surely killed them. The tank shot straight up to the ceiling/garage door tracks/door btw. Knowing that and seeing the damage was shocking.
@@andrewhigdon8346 That's why you test tanks with water rather than air. Water doesn't compress, so if the tank does pop, all you get is a bit of a splash rather than an explosion. And you test it to well above its rated pressure to make sure it won't fail under normal operating conditions. I'm not 100% confident I'd try this myself but I've seen it done and it seems reasonable.
The HD stamp is hydro test , in order for any tank to be allowed as a compressor it has to be tested using water or glycol . that was my job when I worked on oil seperators, we would have to fill the tank from the bottom (if done from the top you will have air and will not be able to test) we had to test 1 1/2 times the working pressure which is where the 225 stamp comes in. It's a max psi of 150 so 150 +75 =225 . it has to hold that pressure for 15 min. And all welds are checked for any leak.
By law anything over 110 psi has to be filled with liquid so that if there is a stress crack , or a faulty weld you take a quick shower otherwise goid chance your not going to be around for any other test as it will explode like a grenade shooting metal into whoever is near the tank. If a tank gets to thin from water, rust you can cut a section out and basically put a new piece in a band aid . the second serial no. Is logged into a federal data base which is a paper trailall the numbers on that tag will tell you where that steel waa milled and when , who welded on that tank , who pressure tested that tank and who did the final inspection giving that tank a pass to become a compressor.
So all them tags and numbers are it's birth certificate if you will.
I think i depends on how will you take care of it. If you put a water separator / dryer in right after the pump. It could last for a very long time. That is what I am planing on doing when I get my big compressor.
Interesting to see the condition of the inside of the tank. In the future you could remove the fixtures, hook up a pressure gauge, fill it with water then hook up a pressure washer to hydro test it yourself. Also you can get a boroscope camera that hooks up to your phone for less than $20.
Someone in another video mentioned that along with HD testing a tank. His EXPLODED..
I would have thought an explosion most unlikely, one of those pits would get so weak it would just give way and you'd hear a nice hissing. Also why would it crack, unless you'd damaged the outside severely somehow, since it has been clearly ok for 37 years? Elf and safety gone mad sir!
37 is nothing we have two 250 litre ones the youngest one is 55 years old. The other is much older. Both pass inspection every year. I was just thinking how sad it was to cut this up. What a waste. Out side in a shelter that would contain it if they popped it wouldn’t be a problem anyway.
Yeah I think most explosions would be due to the pressure regulator or pressure relief valve not working properly combined with a rusty old tank. Oh hold on... 😂👍
@@GosforthHandyman ive had tanks rist through they hissed i welded the hole shut to get the job done and didn't remember till the next year when another spot rusted through lol
@@timjohnson6864 Then watch this, and think again..... l.facebook.com/l.php?u=https%3A%2F%2Fwww.youtube.com%2Fwatch%3Fv%3DKVP_A7eGYxw%26feature%3Demb_logo%26fbclid%3DIwAR08LhsBqi-LhRGkrIcYJCxBlpxMp9UNZ7JNoyTOGGeL7b06-R-P80GhC48&h=AT1-eecFdf5AqjejmEptqbJ_rCO_78f9XJXGmlphoi4TA_xm-7PqRsmYxuoq_C0SceRo8pN9ntij7LQKxZoqdiFpjIomxUrZ1tEDltvGNrxywXfTcnAkpGEIn0ldutSmKx41_QC0JVsgrn0Y
An explosion may be rare, but it does happen. Hydro-test results save you from injuries.
I did have a tank rust out on me and it didn't explode. It was the small 10/15L type and was about 15 years old. What actually happened was.. as you show.. a ribbon of rust pits or holes along the bottom inside of the cylinder and evenually one breaks through so you get a small whistle and obviously it doesn't hold the full pressure any more.. The first hole is probably only a pin hole but does make you aware... so you explore and quickly find the offending area.. You think about repairs.. bit of welding (can't do that..) an epoxy patch.. (nah..) screw a plate of metal over the area.. (probably the best option.. ) Have a cuppa tea.. think.. Snip off any extraneous useful looking bits and kick it to the curb.. Hello Machine mart.. whatchgotonoffer..?
you got away lucky some of the units went off link a granade im a small closed garage blowing out all windows imagne you stand next to it
th-cam.com/video/W2LbTHfU5fQ/w-d-xo.html
All Compressors have a Safety Valve. The tanks are designed to take at least 600psi which is probably 3 x the pressure your engine/pump could deliver.
At work I took over responsibility for an at least ten year old clark whisssper all in one compressor. I could hear water sloshing about inside the tank. I removed the drain tap and strangely no air or water came out. on further investigation I found that although the drain threaded boss had been welded to the tank the tank had not been drilled by the manufacturer. I returned the unit to Clarks R & D dept. it came back a few weeks later with a hole drilled through the drain boss so the drain tap worked. strangely enough it failed completely a few weeks later. I wondered how many of that batch hadn't had the drain hole drilled through at manufacture.
wow... good to know which brand I'm NOT goung to buy from. thanks
I worked for a company that used air compressors to operate gas/air pumps, and the compressors had to be serviced regularly ie change pressure valves,air filters etc and replaced every ten years.So you got good service from your old one, but definitely time for a new one.
Large ones in industrial plant I have seen them up to 60 years old and still in use. They get hydro tested every year during shutdown (regulations say every 5 years, but they are figuring as the plant is being shut down might as well do it as well) as to replace them will mean dismantling large chunks of buildings and removing plant and roof to get cranes in. Tossing after 10 years on a small one is possible, as the test after that time, and fixing it, probably is approaching the cost of a new one anyway. But on large units you will want those parts to last a long time, so regular service of the compressors, change oil regular and so on.
It really depends on how well the tank has been taken care of and the quality. My dad‘s old speed air lasted 30 years and it still works. I’m just afraid to use it anymore and it has not been taken care of very well to be quite honest, I think you just comes down to quality in this case in this case
"The prime directive - we do not fuck with pressure vessels."
You could have made a small forge of the tank if you're into that sort of things. Pask Makes did a forge pig to heat treat steel to make his own tools etc. The motor is also still usable to make other machinery.
I bought a Kobalt 26 gallon one. Its 15 years old but looks fine on the outside. Think in should look inside?
was he cutting into that with a grinding disk?
Hyd probably means hydraulic. It was probably filled with fluid, and pressurised in the same way as scuba tanks are.
For anybody interested, the formula used to calculate the hoop stress in a cylinder, (the most heavily stressed part being the parallel sided portion) is PD/2T, i.e. internal pressure x diameter divided by twice the wall thickness. With deep drawn cylinders the burst failure is normally a straight line down the longitudinal axis; with welded (rusty) tanks it can be more chaotic but it is surprising what decent steel can withstand. Even the humble 15mm copper pipe can theoretically withstand more than 20 bar of internal pressure, though I don't think I'd like to cycle it too often!!
I don't know why more compressors don't come with a 1/4 turn valve for draining. I have a 1/4turn on my big compressor and a screw type on my small compressor. The big one gets drained everytime I use it, the small one gets drained about once a year.
I have a soviet compressor, an old man used it für 40 yrs and i borrowed it für one day and end of the day the tank started to leake air at the welds, turned out its lifespan was exacly 40 yrs.
This definitely has me thinking about my compressor. It is at least 12 years old and has a broken wheel on it that I have been meaning to repair but maybe it isn’t even worth it. I didn’t even think that it would have a short life span.
You could have used this as a secondary air tank for your new compressor Andy,
You get more air flow then, just fill a check valve, look up on YT about it
That’s actually pretty thick tank in comparison to the small twin tank units the real shame is how much longer that compressor would have worked if the manufacturer had spent even a few seconds to spray some self etching weld through primer inside it prior to it being welded together. My next tank have powder coating inside - u can’t expect bar steel to survive
Yes that is plain hot rolled steel scale, if they had at least done an acid etch on the inside after welding, and a quick thin electrogalvanise coating on the whole unit, followed by a bake to get the hydrogen out, it would last a really long time, or just have a sacrificial anode rod on the bottom that you can unscrew and replace every few years.
Powder coating acts as a scab at first penetration then traps moisture. I've seen it on many pieces of coated equipment bought at auction. Consider self-etching (powder coat is not) paint/primer instead.
I would have removed the end plug and used a lighted scope to check the interior .
Great video. Pretty scary when you think about it. I’m not sure I even trust brand new tanks considering the quality of manufacture on everything nowadays. I’m going to make sure mine is far enough away from me in a worst case scenario.
Seeing a pressure vessel tag welded to the tank is a higher quality tank also bung plugs welded to the tank
the tank was tested to like twice it's operating pressure, so it should be fine with like half the metal gone even.
Great video, very informative!
If that's used at home, there's no regulation (other than the usual CE Marking for supply) that mandates any regular inspection.
But if it's used in a workplace, and the volume x pressure is more than 250 Bar Litres (excluding the 24 Litre, 10 Bar "Hobby Compressors"), it would legally need a WSE (Written Scheme of Examination) under PSSR (Pressure Systems Safety Regulation):2000, which would dictate (certified by a "competent person", based on a risk assessment) what degree of inspection (typically ultrasonic thickness test for the receiver and a pressure test of the PRV and Gauges against a calibrated gauge).
The receivers ("pressure vessels") are always supplied against a design code (should be stated on teh data plate!) which specifies the minimum design thickness, plus a corrosion allowance (EN 286-1 is typically 2mm + 0.5mm for steel, but older codes had a greater thickness).
That one was probably the older BS 5169, possibly with 3mm + 0.75mm corrosion allowance.
Life expectancy will depend on how often the condensate is drained from the receiver and often it's the compressor (especially if not regularly maintained) that limits the life...
Modern industrial compressors tend to be coupled with an automatic timed or zero-loss drain, so you don't have to remember to do it manually.
Its old machinery, of course it still works. No PCB board, no pre-installed failures... Solid item.
Personally, I have always been terrified of air compressors, as well as flammable gases . Worst of all, flammable compressed gases (propane tanks, butane cans) and I have always wondered why these aren't made of stainless steel, or at least coated internally with a paint or protectant to prevent rust... I mean, the inside is never touched by solids, it wouldnt degrade at all presumably...
That reminds me. I've not drained mine for a couple of years. Maybe that's why it acts more like a pressure washer than a compressor :)
Funny that, mine gets drained fairly often and it's more of a pressure washer too
@@coldblu357 I've always wondered how moisture gets out of a compressor. You drain all the water out but the humidity stays in there unless it somehow evaporates out of that tiny valve hole. You may not have standing water but you'd have to leave the tank out in the sun for quite a long time for it to actually dry out inside.
@@randywl8925 When the air gets pumped in hot it creates moisture. Some people coil the feed line from the pump to the tank or add an air cooler in line to help with moisture. I learned it from the guys that paint, they know all the cool tricks.
Years of life left in that
3:14 Hydraulic test. it's a test where you add water under pressure and see until where it can hold that pressure. I've done it in a boiler with a manual pump and let me tell you it's not a small feat. Generally the hydraulic test is done @ 200%- 250% the real working pressure
The correct way to do this would have been to perform a 'house' hydraulic test first, then open it up and see how the steel was, thus establishing at least some correlation. As it is we have no actual information, though given the 2.4mm residual thickness I agree with a prior commenter, it would probably last about as much at is already has at least.
Hyd. test is probably hydrostatic test pressure. Filled with water and pressurised. I did this sort of testing as part of my fitter / machinist apprenticeship. Company manufactured flow control and safety release valves.
Stainless Steel tanks can be used right to avoid corrosion?
I doubt they make them anywhere near that wall thickness anymore.
I think that small pressure tanks are supposed to be replaced after ten years from test date,in industrial and commercial use they have to inspected on a regular basis by a competent person like once a year, insurance companies will usually arrange this.
Now to cut open a brand new ALDI compressor and see what's better!
Actually I've done that, A mate got one a fair few years back and due to his own stupidity he ran it without oil, so he gave it to me to turn it into a bbq (I do the same with Gas Bottles) and the Aldi tank was in really decent condition with the wall thickness around 3mm I believe, which is the same for calor gas bottles.
Hyd. stands for hydraulic. As other comments have said, liquid (hydraulic) testing is much safer than gas (air) testing 'cos if it fails it won't explode - but you might get wet!
Using a grinding disc instead of a cutoff disc?
HYD means that they filled it with liquid or hydraulically tested it to that pressure so that if the tank did let go it was with water or oil that is not compressible so their is no violent explosion. Just a mild pop of liquid that would startle you but not violently blow the windows out of your shed and send the tank through your roof They always test at higher pressure with liquid filling the tank. I have tested tanks using water and a grease gun to pressurize it.
Condensation is corrosive. And since the compressed air is warm. It's going to raise to the top. Thats just my thoughts
I just adjusted my cut out down to 50 lbs, only doing tires occasionally. I don't need 150 lbs out of my old Craftsman. I guess I feel a bit safer, after seeing the explosion videos.
Why don't they line the inside where condensation begins.
Or line the in side with stainless I don't know but anything might be better than a material that gets rusty you think.
In a commercial setting this tank would be classified as a pressure vessel subject to statutory inspection by a competent person. There’s so many small DIY / trade vessels it’s impractical to have them inspected as they should be.
Most comments focused on a corrosion pit failing to a simple leak. That does happen and it has to be your luckiest day when you discover it.
Very few suggested rupture of the vessel. This is the reason for statutory inspection. While industrial size vessels can destroy buildings, small vessels are used in the same room as the user. Personal injury is likely, so I would worry the growing and aging fleet of small cheap compressors is a growing risk.
First, look at your use. If it’s running every day you should get serious about inspection, get an expert technician on board or become one as best you can. Less frequent use; be sure to drain fully after use, maybe open the vent plugs to dry the tank, peer into the vent holes looking for rust along the waterline per this video. Either way you won’t have the ultrasonic gear to properly inspect for wastage of the tank due to inevitable corrosion.
Above all, don’t prolong the life of the vessel beyond a sensible period. Some of the ages quoted above are nuts, given the potential risk. Buy a new one as soon as you get any excuse.
Yup - I think the attitude of "it'll be fine, what a waste" etc. is a very bad message to put out. Great comments Jim. 👍
I need to get a bore scope so can look inside mine. It's a 60 gallon Coleman I bought new in 2000 at CostCo. It only gets occasional use, but I live in a very wet and cold climate. It'll be interesting to see inside.
My Campbell Hausfield was purchased in 2000. It developed a pin hole leak in 2017 were the longitudinal weld meets the end bell weld. Tha autopsy revealed little rust were the pin hole developed but a heavy belt of rust along the bottom. The 13 gallon tank walls were only 3/32 inch metal.
Wow, for 37 yrs that is fantastic.Doesn't owe anything
Yup - it's done well!! 👍👊
You get a lot of condensation inside any pressure vessel. The shorthand life of a pressure vessel is ten years, then inspection is required... Most of us get complacent enough with gas bottles, so unfortunately air bottles seem to get ignored until something goes wrong.
Because standards have changed over the last half century, you just sacrificed a really well manufactured product for one that begins life at 1/8 the thickness.
If you were worried about the state there ways to measure and determine metal thickness.
So true. I have an old Craftsman with a DeVilbiss tank, and an old Ingersoll Rand with (believe it or not) an Ingersoll Rand tank and a mag starter. Bought the Rand at Home Depot!
The industrial brands are still good, just hella expensive. I don't think any of those guys (Schulz, et al.) make small portable units. Let me know if you see one. I'll recommend it.
Next time Hydo test, read the inspection label on tank for max psi. Fill tank full of water, install 2x psi gauge, hook pressure wash wand to tank and pressuruze tank to 2x rating.
I have and use a 50+ year old 60 gallon 2-stage. I've had fittings fail, but never an issue with the tank or welded bungs.
Can you treat the in side with an rust prohibitor ?
I bought a new Makita air compressor I see rusty water come out when I drain it .
I've seen comments from people who did that and it was ineffective. High end brands, like Schulz, powder coat the tank inner walls at the factory.
Don't worry about your Makita. The drain water will be rusty from day one. I have a 30 year old Ingersoll Rand (U.S. made back then). It's drain water appearance has been consistent over the decades.
A galvanized tank is advised, Elmag makes ones with 15 years warranty o the tank.
No Andy... it isn't heavier... we're _older_ now :^)
Even draining regularly I won't keep compressors around forever. Just not worth the risk over time.
EDIT: Can't find it now, but looking at compressors recently I recall one of them said to replace after 5 years of service. They have expiry dates on the tags now like gas cylinders.
Yeah I'm sure I've seen the 5 year thing mentioned somewhere too - probably to keep them in business but even so 37 yrs is probably pushing it. 😂👍
@@GosforthHandyman in canada they require hydro test at every five year of service in commercial environnement,
In Europe there is no official age limit, however commercially used compressors have to be checked by hydro test every 10 years.
Tanks which are coated inside can withstand decades without corrosion, you can recognize it if the water you drain is white, or rusty. Big tanks here have a hole which can be opened for seeing inside the tank.
Just found mine has recently gone, got a hairline crack at the top where the motor bracket welds to the tank is. I guess the motor vibration added to that. I picked it up second hand around 8-9 years ago, didnt know the history of it but have been meaning to replace it as whenever i drain it, rusty coloured water. Took the motor and fittings off it, and been thinking about converting a gas bottle. But will probably end up buying a brand new one.
Think i might cut the remains of mine open now, see how bad it is.
High cycle fatigue. Like an old aircraft. Get rid of it.
I have an uncle who build his own compressor with a fridge engine or motor (I'm French so sorry for bad English).
And I think the tank was a large scuba tank.
I've had my compressor since 2004...........never drained the tank!!, the last time I had a go the drain valve was seized, should I stop using it?
How come they don't galvanize the insides of the tanks?
Good question. Galvanizing may not be effective at high pressures. There are powder coated tanks.
I dont think many people realise the danger of a compressed air tank or how they can be safely pressure checked.
Hydro testing is a safe way to check the soundness of an air tank. Water wont explode if a seam seperates it just splits open and the water drains out.... So if you fill your compressor tank with water and have a way to overpressure the vessel, thats how its done. I usually check my tanks at 100 to 150 percent over rated pressure.
I found your video most interesting as I have exactly the same compressor which I purchased from Machine Mart in 1983 - it has the same datte of test etc. It has served me well and continues to do so never missing a beat they were made in Italy as was my MIG welder. Everything seems to be made in China now.
My POS porter cable pancake actually has a 'don't use tanker after' date stamped on the bottom. That date is 2022 so I'm shopping for a new one.
This old one it was fine in your shop 5 yrs ? 15 yrs ?
How often was the water bleed from the compressor
Just before you start cutting is where you hope it was actually dead... extremely interesting to see just what happens in there and how well the airmaster compressors were made. But I am now thinking about the old one I just replaced and thinking I should recycle it.