# Compressor exploded



## RYAN S (Jun 11, 2019)

A good friend sent me this picture of his step fathers 40 year old air compressor that exploded today. As far as I know he is alright after a trip to the ER for stitches. From what I gather he had not drained the tank in thirty years or so, it got to 95psi and went boom.  Probably a good reminder to drain and check our tanks regularly.


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## Shootymacshootface (Jun 11, 2019)

That is scary as all hell.


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## ttabbal (Jun 12, 2019)

Yikes! I installed a pipe on the bottom that comes out to a ball valve. Makes draining a lot easier. I don't often get much, low humidity most of the time here, but I like knowing it's been done. Mine is an 80 gallon vertical, so there's a lot of energy in there. Might be a good idea to enclose it a bit...


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## Janderso (Jun 12, 2019)

Ouch, how many of us have old compressors and have no idea of the condition of the tank.
At work we have OSHA come in every 5 years to certify.
Glad he didn’t get hurt too bad?


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## matthewsx (Jun 12, 2019)

There's a similar tank outside the compressor service place in town. I also did the valve piped from the bottom of mine since I don't have much info on how it was treated before I got it. I also installed a lower shutoff pressure switch when I had to replace it this year. The guy at the shop said draining should make a big difference and dropping it down to 125psi was a good idea for the motor and pump as well as less pressure in the tank.

Be careful out there....

John


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## bakrch (Jun 12, 2019)

Pretty sure I left my compressor on last night, and now I'm 68 miles away from it ... gah. Luckily it is new, probably okay for now.


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## Ken from ontario (Jun 12, 2019)

bakrch said:


> Pretty sure I left my compressor on last night, and now I'm 68 miles away from it ... gah. Luckily it is new, probably okay for now.


The worst case scenario is that the hose leaks a bit of air and your compressor goes on/off ,it might be annoying to your neighbors during the night.


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## Bob Korves (Jun 12, 2019)

For helping us to drain them more often, the method big trucks use to drain their air tanks is simple, cheap, and more likely to be used often:




__





						Search results for: 'ri r95512103'
					






					peterbiltparts.com
				



Pull the cable sideways to the pipe thread in any direction to drain.  Spring loaded to return to air tight.  Reliable.


There are also automatic drain valves that work with compressor unloaders:


			http://www.plazafleetparts.com/uploads/2/1/9/0/2190100/dv-2_drain_valve_installation.pdf
		



Which can also be bought with the manual drain valve pictured above already installed.  They are not expensive, and are robust.  All mechanical, no electricity needed.  A version with a 12VDC heater is also available for use in freezing conditions.  Proven on millions of trucks running in all kinds of extreme conditions.  They are available at any store that sells heavy truck parts.  1/4" NPT mounting threads.


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## Ken from ontario (Jun 12, 2019)

Janderso said:


> Ouch, how many of us have old compressors and have no idea of the condition of the tank.


And how many of us see these 40 /50 year old compressors for sale and think , wow what a great deal.


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## dlane (Jun 12, 2019)

I had a used 80 gal vert IR given to me a while back , there was signs of rust in the tank drain bung, I opened the side 2” bung and sprayed way oil into the tank with a paint spray rig till a fog was in the tank thinking it would slow the rust down
I would think coating the inside of the tank with rust preventing paint from the factory would be a good idea .
I did lower the pressure to 125 from 180 and put it out side the shop in its own inclosure with a filter/regulator on it plumbed thru the wall , think it’ll be ok for a while.


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## Flyinfool (Jun 12, 2019)

I wonder if it would work to use one of the treatments that are made for sealing gas tanks that are rusting from the inside. This would kill any rust living in the tank and leave a coating to help prevent further rust.

I had been looking at getting a automatic drain kit for my 40 year old compressor.








						Timed Electric Auto Drain Valve Compressor Gas Tank Automatic 2 Way AC 110v for sale online | eBay
					

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This has a timer that will drain the water after an amount of run time that you set. So the more I use it the more often it will drain itself.
After seeing this I think I will order that now. And maybe a coating kit for the inside too.


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## astjp2 (Jun 12, 2019)

Janderso said:


> Ouch, how many of us have old compressors and have no idea of the condition of the tank.
> At work we have OSHA come in every 5 years to certify.
> Glad he didn’t get hurt too bad?


OSHA does not certify tanks...they are a government agency who investigates and inspects...


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## north1 (Jun 12, 2019)

Never, ever leave your compressor switch on for an extended time frame.  Know of two neighbors who lost their shops to fire because of compressors.  Leak, faulty valve and or regulators fail.  Then your compressor runs until it has no oil and burns up causing a fire.


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## astjp2 (Jun 12, 2019)

My shop compressor has not been turned off in 8 years...


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## MikeInOr (Jun 12, 2019)

I haven't drained my compressor since I got it.  When I got it I put on one of these HF $7.49 auto drain valves and the tank is drained at the end of every cycle:
https://www.harborfreight.com/automatic-compressor-drain-kit-68244.html 


I actually built my compressor out of a nice old industrial compressor pump with a rusted out tank and the 40 gal tank from a direct drive compressor with a bad direct drive pump.  When I did the transplant I put a little liquefied (heated) heavy cosmoline grease in the bottom of the tank and swished it around a bit to help prevent rusting.  The old compressor leaked profusely through many pin holes in the bottom of the tank... I guess the previous owner was lucky the tank didn't explode on him.


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## cjtoombs (Jun 12, 2019)

I have an automatic drain valve on mine, it cycles every hour or so whether the compressor is running or not.


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## stioc (Jun 12, 2019)

Is there a way to tell the inside condition of a tank? While I've always drained my 25 gal craftsman after every use, still, it is about 20 yrs old now (but looks brand new since it hasn't been used all that much).


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## astjp2 (Jun 12, 2019)

Borescope or hydrostatic test.  MY compressor tank is from the 60's


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## Superburban (Jun 12, 2019)

stioc said:


> Is there a way to tell the inside condition of a tank? While I've always drained my 25 gal craftsman after every use, still, it is about 20 yrs old now (but looks brand new since it hasn't been used all that much).


 There is several videos on Youtube (I think Keith Rucker has one), that show how to do a hydro test, using a pressure washer to build up the pressure.




MikeInOr said:


> I haven't drained my compressor since I got it.  When I got it I put on one of these HF $7.49 auto drain valves and the tank is drained at the end of every cycle:
> https://www.harborfreight.com/automatic-compressor-drain-kit-68244.html


Thats what I use. Since I do not use the air for painting, I have it set up so that I can spray some oil (Usually marvel mystery oil) into the tank. I have the auto drain kit, drain into a small pan, so I can look for water in the oil, which Has always been dry (love living in a desert).


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## silence dogood (Jun 12, 2019)

The tank is not the only thing to check.  MY neighbor's blew a crank and left pieces on his garage floor. Fortunately, no one got hurt.


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## BGHansen (Jun 12, 2019)

Good thing no one was seriously injured.  Lot of energy stored in that tank when it went.

My dad has an old Sears compressor used for painting though he only used it to pressurize the chemical tanks on a Sickles E-4 film processor.  I used it for air nailers back in the day.  Very quiet compressor, maybe a 1/2 HP motor, then I started hearing a "hiss" after it hit pressure.  Tank had rotted through at the bottom.  You guessed it, compressor had never been drained in 20+ years.  I tried MIG'ing the thin spots to plug them, but kept burning through.  I patched the holes with JB weld and welded a piece of 16-gauge stock well past the thin spots, has held up to very limited (tire pumping) use sense.  But I think we'll retire it and use a $40 import after seeing these photos.

Bruce


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## MontanaLon (Jun 12, 2019)

Had an acquaintance who said his compressor was acting weird. Big 80 gallon thing. Would run and register pressure and then shut off but would only run his impact wrench for about 30 seconds before it kicked on again. Would fill up really quick and shut off and it seemed as soon as he started to work it would kick on again. Went to check it out and found it was still bolted to the shipping pallet. I told him he really needed to bolt it to the floor so it didn't get knocked over and pushed on it. Thing didn't budge even a millimeter. Pushed harder and it weighed a lot more than it should have. Reached under and cracked the drain valve open and then watched as 79.5 gallons of rusty sludge spewed out on the floor of his shop and snaked toward the drain that was 3 feet away. I should have known when he said, "Whatcha doin?" when I reached under it, then I realized, there was no rust stain on the floor. He didn't know the thing had a drain on it. Had bought it 20 some years before and it sat in an unheated garage undrained ever since. He had maintained it well otherwise. Oil changes, filter changes, belts etc.

I unplugged it and told him he needed to have it checked as the tank was no longer safe and I didn't want to be around if it let go. He told me later he had a guy come and pressure test it and the tank failed at 158 pounds of pressure. I'm not sure what the pop off valve on it was but I think the pressure on the gauge when I got there was at 140 pounds. He ended up buying a new tank for it and getting an automatic drain valve too.

I know another guy that was nearly killed by a beer keg that busted by being over pressurized hooking it to an air compressor for "extra capacity" on his shop compressor. You don't mess with compressed air, it can kill you.


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## Cadillac (Jun 12, 2019)

I have a 2 stage 60gal compressor on the floor of my garage and another 60gal reservoir tank in the rafters drywalled ceilings. Garage is plumbed with d.o.t. 5/8 air line with push connect fittings for all connections. Have air connections every eight feet on the walls and two drops in the ceiling. I use to leave the compressor on all the time until one morning. I’m leaving for work passing the garage and I hear the compressor running. I unlock the door and open and the whole garage was filled with a oily smoke. I immediately ran and shut down the compressor. Found the tank fill line had broke right above the unloader valve on top the tank. Luckily nothing bad happened garage stunk for weeks. I replaced that hard line with a braided flex line which had been running strong for about 10yrs. 
 I do drain my tank every so often and don’t get much water maybe a cup. My problem is valve on bottom of tank gets gunked up not liking to drain well.


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## Boswell (Jun 12, 2019)

this is a wake up call for me. I have an old Curtis make in the late 50's with the original tank. I drain it often but we have enough humidity that there is always water when I drain it. It is always rusty water. I always thought the failure mode would be a pinhole leak and it would just not hold air anymore. Now I think I should be looking at a new tank. Soon.


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## hman (Jun 13, 2019)

Cadillac said:


> Found the tank fill line had broke right above the unloader valve on top the tank. Luckily nothing bad happened garage stunk for weeks. I replaced that hard line with a braided flex line which had been running strong for about 10yrs.


When I bought my house/shop, the P.O. left his 5HP compressor in the small attached room behind the shop.  It was a beast, very old, crusty with a mix of dust and oil.  Dragged it out of the "building" with a come-along.  Opened the tank drain, and it must have had 2 gallons of water inside.  I gave it to another member of the local machinists' club, who said he'd dump the tank and keep the pump.

I did notice one very good feature of the original installation - the output air line was a 3 foot length of hydraulic hose - great vibration isolation between the tank and the (copper) air pipe into the shop.  When it came time to install my own (~2 year old) compressor, I went to Tractor Supply and bought a new hydraulic hose to connect it with.  I also cobbled up an automatic drain valve, which opens for about 30 seconds every time the compressor starts.


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## MikeInOr (Jun 13, 2019)

hman said:


> When I bought my house/shop, the P.O. left his 5HP compressor in the small attached room behind the shop.  It was a beast, very old, crusty with a mix of dust and oil.  Dragged it out of the "building" with a come-along.  Opened the tank drain, and it must have had 2 gallons of water inside.  I gave it to another member of the local machinists' club, who said he'd dump the tank and keep the pump.
> 
> I did notice one very good feature of the original installation - the output air line was a 3 foot length of hydraulic hose - great vibration isolation between the tank and the (copper) air pipe into the shop.  When it came time to install my own (~2 year old) compressor, I went to Tractor Supply and bought a new hydraulic hose to connect it with.  I also cobbled up an automatic drain valve, which opens for about 30 seconds every time the compressor starts.



When I grafted my old industrial pump on its new tank I also went with hydraulic hose and AN connectors between the pump and the tank.  That was about 15 years ago and it has been holding up great!  The local CarQuest auto parts store had a great selection of AN connectors and cloth jacketed hydraulic hose... they made for very easy sturdy DIY custom hoses.


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## bretthl (Jun 14, 2019)

That exploded compressor looks familiar ... thanks for the reminder.


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## NortonDommi (Jun 14, 2019)

When I built mine up I gave it three coats of PA 10 and two coats of International 2K bottom paint on the inside, custom made tank with 1/2" wall. 42 years and the drain water comes out clean.  I have bought a new bigger compressor and the tank has much thinner walls so I'll be doing the same before putting into service.
  I've seen inside some old tanks and most have had about an 1/2" - 1" of water sitting them during use and you can see a line of pitting all around the tank.  I've never seen a tank painted/sealed from the factory.


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## Flyinfool (Jun 14, 2019)

I contacted Red-Kote tank repair and they said that their product is made to be resistant to gas and all of its additives but is water soluble. Back to looking for something else to pour into my tank to kill the rust and coat it to prevent further rust.

Or I may just start shopping for a new bigger tank. As long as I drain it regularly it will outlive me.


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## DiscoDan (Jun 14, 2019)

I just went out and drained my ancient Craftsman and as always, water comes out clean. Not a speck of rust. Like others, I added a ball valve to mine as well as a short extension to get it out where I can easily get to it.


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## Boswell (Jun 14, 2019)

If you go out to Compressor world and want to order a tank. They give some choices on coatings.  You can get it powder coated (Interior,  Exterior or both), you can get it Galvanized (interior and exterior) Both options are expensive with galvanizing 1/3 MORE than the cost of the tank.  Anyone have opinions on if either treatment is worth the significant extra cost?


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## Flyinfool (Jun 14, 2019)

Any coating on the inside should be an increase in tank life. the best coating in the world does not save you from having to drain the water.


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## Superburban (Jun 14, 2019)

I think the galvanizing would be better, But they cannot galvanize, or powder coat the threads for the drain valve, so there will always be a place for rust to start. Thats why I add some oil to the line going into the tank every month or so. Except maybe for tires, there is nothing that I use the air for that the oil will hurt.

The coolest setup I have seen, and what I will someday copy. A truck maintenance shop in Pa, had two compressors, each fed into its own 15  or so gal tank, which then fed into a large 50 gal tank. Had a setup so that each compressor alternated which one started each time, and if the air dropped enough, both kicked in. From each compressor to the small tank, was over 10 feet or so of pipe, which he had wire wrapped around, to help it shed off some heat. most of the moisture settled out in the pipe, and small tanks.


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## Dabbler (Jun 14, 2019)

I found a piston compressor for my friend at a garage sale for $10, running.  before we used it, I made sure we checked the tank for corrosion and condition - it turns out it hasn't been run hardly at all, so was in like new3 condition.  It is a 1968 piston compressor, and now that we've checked it out, it runs like a top. 

- IF YOU BUY USED, ALWAYS DO A THOROUGH CHECK OF THE TANK!


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## RYAN S (Jun 14, 2019)

I finally found out that the guys tank who exploded is OK, he got very lucky. Six inch gash in his arm about an inch deep, missed all of the arteries, bone, and ligaments.  He does have some hearing damage.  He was bent over the compressor plugging in a hose when it went. Sounds like he had put a new speed aire pump on two years ago.  About a month ago he looked into a new tank and decided against it. (Bad decision) Apparently it did have a pinhole leak due to rust that would “come and go”.

The thing that surprises me the most is the catastrophic failure of the metal.  The area along the burst line looks like uniform thickness. Almost makes me think the pressure shut off switch malfunctioned.

Hope everyone has a fun and safe Father’s Day weekend!

Ryan


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## Shootymacshootface (Jun 15, 2019)

I was thinking the same thing about the catastrophic failure.


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## Superburban (Jun 15, 2019)

A few things that I see that would be great to get a better look. * The failure is an inch or two from the drain valve. Was the vavlve at the lowest point on the tank? or has there always been an inch or so of water left inside the tank. I do not see where the failure began. so both could just be side issues. *Looks like two metal straps were installed around the tank.  What is their purpose? My first impression is they were installed as abn attempt to keep a rusting tank in use?  * where are the wheels, or feet? The tank looks to have lots of rust/ water on the inside what is now the bottom.

I hope no one takes this as poking fingers, that is not my intention.  Just trying to learn, and help others learn. Any compressed gas is noi\t any thing to mess wiyh.


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## whitmore (Jun 15, 2019)

Ken from ontario said:


> And how many of us see these 40 /50 year old compressors for sale and think , wow what a great deal.


If you want to use an old TANK, it makes sense to pressure-test regularly (fill with WATER for the test, so
there's no stored energy if it breaks).   The compressor isn't what failed, the tank did.

With regular presure-tests, the 2kpsi bottles for compressed gasses can last a LONG time, and they stay safe.


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## Ken from ontario (Jun 15, 2019)

I know many of us here have tons of respect for Tubalcain(Mr. Pete) any enjoy watching his videos, here the one I remember watching that made realize how important it is to make a habit of emptying the tank daily, of course it's easy when the compressor tank is small


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## Bob Korves (Jun 15, 2019)

MikeInOr said:


> I haven't drained my compressor since I got it. When I got it I put on one of these HF $7.49 auto drain valves and the tank is drained at the end of every cycle:
> https://www.harborfreight.com/automatic-compressor-drain-kit-68244.html


Lots of poor reviews...  (???)


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## cjtoombs (Jun 15, 2019)

Superburban said:


> I think the galvanizing would be better, But they cannot galvanize, or powder coat the threads for the drain valve, so there will always be a place for rust to start. Thats why I add some oil to the line going into the tank every month or so. Except maybe for tires, there is nothing that I use the air for that the oil will hurt.
> 
> The coolest setup I have seen, and what I will someday copy. A truck maintenance shop in Pa, had two compressors, each fed into its own 15  or so gal tank, which then fed into a large 50 gal tank. Had a setup so that each compressor alternated which one started each time, and if the air dropped enough, both kicked in. From each compressor to the small tank, was over 10 feet or so of pipe, which he had wire wrapped around, to help it shed off some heat. most of the moisture settled out in the pipe, and small tanks.



The nice thing about galvanizing is that it basically coats the metal with a anodic protection, so it will protect areas that are uncoated, so long as they are close to the coating, so the threaded areas may not be a problem.


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## Jim Dobson (Jun 15, 2019)

I see a fair few aluminium tanks for sale on new compressors here in Oz.


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## TQA222 (Jun 15, 2019)

It seems to me that there will always be some water in the tank even if you drain it daily, So over time there will be corrosion. Will there be more and deeper corrosion if the tank is left half full of water maybe a little but maybe not. 

I used to run a large garage and we had several compressors. Our insurance co required that they be inspected every year and they all had inspection ports maybe 6" x 4" over a 15 year period we had one tank condemned. It was wartime marine stock and came from Rosyth dockyard from a scrapped ship. 

If I had an old air tank I would buy a borescope and do an annual inspection. 

BTW Thin steel ranks scare me see here LINK


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## Superburban (Jun 15, 2019)

Only thing, is a bore scope can miss or just not see a lot of the pitting. Thats why I squirt oil in every month or so, hopefully it keeps the moisture away from the metal. I also have a water separator between the pump, and tank. I think another good idea is a long metal line between the pump and tank, to dissipate some of the heat.


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## whitmore (Jun 15, 2019)

TQA222 said:


> It seems to me that there will always be some water in the tank even if you drain it daily, So over time there will be corrosion.
> BTW Thin steel ranks scare me see here LINK


And, even thick tanks, if not properly engineered and inspected, have a dismal history of accidents: case in point  <https://en.wikipedia.org/wiki/Great_Molasses_Flood>


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## Boswell (Jun 15, 2019)

Perhaps a small (to keep the cost down) aluminum tank for the first tank where most of the water will collect and a larger tank for air volume?


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## hman (Jun 16, 2019)

Superburban said:


> Thats why I squirt oil in every month or so, hopefully it keeps the moisture away from the metal.


OK, just spitballing here ... but because oil floats atop water, I'd be concerned that the moisture on the surface of the tank will somehow keep the oil from getting where it's needed.  But what if you squirted in a bit of a soluble oil (like Kool Mist) instead?  Among other things, it supposedly prevents rusting of machine ways, etc.  

As I said, just a random thought I had.  I'll leave the evaluation/discussion to folks more knowledgable than I am.


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## MikeInOr (Jun 16, 2019)

Bob Korves said:


> Lots of poor reviews...  (???)



Yep, there seems to be several.  I bought mine 15 years ago and the only time I had a problem with it was when I scraped the belly of my compressor over a 2x4 and had to replace an air line.  It is probably not the best for a portable compressor but for my mostly stationary compressor it works fine.


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## mmcmdl (Jun 16, 2019)

All of this makes me want to just live with my leaking tractor tires .


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## Bob Korves (Jun 16, 2019)

mmcmdl said:


> All of this makes me want to just live with my leaking tractor tires .


Get the tires foam filled and forget about them.


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## fixit (Jun 16, 2019)

I worked for 33 years in glass manufacturing.  Compressed air operated the product forming machines. I was a maintenance supervisor in several plants & had air compressor maintenance responsibility on a corporate level for a time. Each plant normally required 3000 t0 5500 horsepower of air compressors online 24/7/365. Draining the air receivers & low points was a major problem. I used automatic valves of all types, electric solenoid, electric motorized valves, float valves, timer controlled air cylinder valves, etc but it still took a person to daily check them. Even then I found people just cracked the bypass valve & let it blow 24/7. One time I estimated we used 500 to 800 HP of air to get rid of water in the lines. I had a solution figured out but corporate would not take the chance. I was going to DEHUMIDIFY the air at the intakes. "Less water in equals less water out." So if you want less water in your air tank, Air condition your shop, get the humidity below 45% you will see a big difference, plus less rust, & you will feel cooler.  Problem solved!


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## Cadillac (Jun 16, 2019)

Por15 is a awesome rust prevention paint. Eastwood company has a comparable frame paint. It’s like a epoxy very durable. Painted dirt bike frames, four wheelers, and work benches. This stuff does not chip off you get on your skin you have to wear it off does not come off naturally. Grreeaatt stuff


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## jdedmon91 (Jun 16, 2019)

Here is what happened to mine 





Sent from my iPhone using Tapatalk


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## pdentrem (Jun 16, 2019)

My dad worked at Harbour Draw swing bridge at Blackrock Buffalo NY, that allowed the railroad to cross the Niagara River and Erie Barge canal. The bridge used air for certain systems and the compressor and tank was mounted in the control house. It was a large tank with thick walls. Every year there was an inspection and on occasion the service staff would drill a blind hole in the side to a certain depth. They said that this would be the weak point if the tank was to over pressure and fail. Eventually they condemned the tank and dad kept the plate.
Pierre


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## Flyinfool (Jun 18, 2019)

With new tanks running in the $300-$600 range (Although if I do go new I will get a bigger tank.) I tried contacting some local places to see if someone would hydro test my tank. I found no takers. 

So I started to look at acquiring an ultrasonic tester to see how much wall I have left. There are a bunch on ebay for around $100.
I was looking at one for $79 (or $54 if I want to have it shipped direct from China). But 1.2mm (0.048 inch) is the thinnest it will measure.








						BENETECH Digital Ultrasonic Thickness Gauge Meter Tester Sound Velocity Meter DR  | eBay
					

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I would hope that my tank is a lot thicker than .050 inch. But many electronic instruments are less accurate when at near the limits of their measuring range. These ultrasonic testers even show that in the specs. ±1% for over 20mm and ±5% for under 20mm. To get to much thinner is a BIG price jump.

Plan B is to buy a pressure washer to build my own pressure tester. I have more other uses for a pressure washer than I do a thickness meter ........... Decisions..........

Yes I am now officially worried about my 35 year old Craftsman 20 gallon tank.


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## f350ca (Jun 18, 2019)

We did a LOT of pressure testing well head equipment up to 20,000 psi. We used an air powered piston pump to slowly build up pressure after you'd filled the gear with a garden hose. We had a regulator feeding the air cylinder that moved the high pressure water cylinder. You could get one stroke at a time to control the high pressure. Can't imagine controlling a pressure washer pump to regulate a couple of hundred psi. A portable hand hydraulic pump would be all you need to build pressure once the tank is filled with water.

Greg


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## MontanaLon (Jun 18, 2019)

It isn't that hard to use a power washer to test with. They have a large pressure but a small volume so you can control it pretty well just bumping the trigger. 

When they hydro tested our SCBA tanks at the FD it wasn't a much more complicated machine that did those. As I recall it had a lower RPM motor than a pressure washer and it was automated so you didn't have to control the pressure yourself but it wasn't some great NASA contraption that they used. 

But it did have a higher pressure than a pressure washer. It went up to at least 6,000 psi and probably higher as the guy was able to run it up to failure on a tank we had that was past its' lifespan. That tank made some weird noises as it exited the world. But overall it was pretty tame compared to a bottle full of air failing.


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## Flyinfool (Jun 18, 2019)

f350ca said:


> A portable hand hydraulic pump would be all you need to build pressure once the tank is filled with water.
> 
> Greg



I like this idea. I just ordered one of these..... It is at least designed to pump water, has a gauge, and can hit up to 1000 psi. All I should need is an adapter hose to connect it once I see what threads are needed.








						Hydraulic Pressure Test Pump 69Bar Hand Pump Manual 1000psi For  water, oil US  | eBay
					

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Now I can host a tank testing party....


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## f350ca (Jun 18, 2019)

That should more than do the job. Arrange the tank to get your inlet at the top and fill with a garden hose,
It was a pump like this we used.
https://www.haskel.com/products/pneumatic-pumps/liquid-pumps/#benefits
A styrofoam cup inside the the riser we would test would come out looking like a shot glass after it saw 20,000 psi.

Greg


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## Flyinfool (Jun 18, 2019)

First I have to disassemble, and do it without air tools.......

We used to test items that went thru the hull of a nuke submarine. Those were real interesting pressure tests. half the time it would blow the gasket on the pressure vessel before we reached test pressure. That was always fun.


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## cjtoombs (Jun 19, 2019)

Jim Dobson said:


> I see a fair few aluminium tanks for sale on new compressors here in Oz.



Aluminum may be better for corrosion, but it has no lower fatigue limit like steel does, which is to say, every time the compressor cycles you are removing fatigue life from the tank.  It will eventually fatigue out and fail, probably catastrophically.  I suspect that they have taken that into account by ensuring that the life of the compressor is short enough not to get to that point, or they plan to be out of business before they start failing, either way there's no problem for the manufacturer.


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## Dabbler (Jun 19, 2019)

Both steel and aluminum have an elastic range that will allow movement without appreciable stress fracturing.  In aluminum it is much lower than steel.  By designing it correctly and aluminum tank can last as long as steel.  Now for the design of consumer products... well, just don't get me started...


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## pontiac428 (Jun 19, 2019)

I'm getting scared for y'all with these home hydrostatic tests with no means of pressure measurement or control.  At least fill the tank with water and immerse it in a bath (or horse trough or swimming pool) when you put the pressure to it.  That way if it blows up, er, fails, it'll just go flub and that's it.


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## TQA222 (Jun 19, 2019)

Keith Rucker diy hydro test using a pressure washer


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## Flyinfool (Jun 19, 2019)

pontiac428 said:


> I'm getting scared for y'all with these home hydrostatic tests with no means of pressure measurement or control.  At least fill the tank with water and immerse it in a bath (or horse trough or swimming pool) when you put the pressure to it.  That way if it blows up, er, fails, it'll just go flub and that's it.



Not trying to make light of your concern. Just trying to address it.
The very definition of hydro static test is to fill it with water. I did not see anyone post about not using a gauge for measurement.
If you put the tank being tested into a bigger tank of water, how do you spot a leak that is not a catastrophic failure? If the tank is full of water it will not fail spectacularly.


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## Superburban (Jun 19, 2019)

So how come water heaters go bang.


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## Bob Korves (Jun 19, 2019)

TQA222 said:


> Keith Rucker diy hydro test using a pressure washer


That test was widely criticized by viewers, whether right or wrong...  Read the comments to the video.


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## Flyinfool (Jun 19, 2019)

Superburban said:


> So how come water heaters go bang.



Because it is no longer filled with water, the water has become steam which is way more dangerous than air.


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## Superburban (Jun 19, 2019)

Flyinfool said:


> Because it is no longer filled with water, the water has become steam which is way more dangerous than air.


Thats it, I was having a brain fart, and could not think of it.  Thanks


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## Boswell (Jun 20, 2019)

I worked for a company that made industrial sized heat exchangers. Every one was hydrostatically tested.  They just filled them with water and then used high pressure air to apply the test pressure.  The very small amount of compressible air was not enough to be dangerous if the pressure vessel failed.  They did this several times a week in the middle of the shop floor.


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## Bob Korves (Jun 20, 2019)

Boswell said:


> The very small amount of compressible air was not enough to be dangerous if the pressure vessel failed.


Air storage tanks hold well more than enough air to be mortally dangerous.


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## Boswell (Jun 20, 2019)

Bob Korves said:


> Air storage tanks hold well more than enough air to be mortally dangerous.


I probably did not state it well. The tanks were full of water and then air pressure was applied. The only air was the air in the supply line to the tank under pressure. So the volume of air was what was between the regulator and the tank. I think in this case about a foot. Critical of course that the tank be 100% full of non-compressible (water) the tiny amount of air just provided the pressure


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## Bob Korves (Jun 20, 2019)

Boswell said:


> I probably did not state it well. The tanks were full of water and then air pressure was applied. The only air was the air in the supply line to the tank under pressure. So the volume of air was what was between the regulator and the tank. I think in this case about a foot. Critical of course that the tank be 100% full of non-compressible (water) the tiny amount of air just provided the pressure


You stated it correctly, Boswell.  Heat exchangers have a relatively small volume, and when full of water are not likely very dangerous at all.  Tanks that store compressed air have a much larger volume of air and are quite dangerous if not used and cared for with respect for the danger.  I was trying to press home that what you posted is quite different than a shop air tank.  Of course, anytime you are working with compressed air there is a chance of something failing, and it is smart to respect it and at least wear safety glasses in the area.


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## cjtoombs (Jun 20, 2019)

I know they test high pressure cylinders in a water bath, but the purpose of that is to measure the level in the bath at unpressurized and pressurized condition, then they calculate the volume displaced by the cylinder, there is a no-go expansion amount at which the cylinder is scrapped.  As stated above, it isn't necessary for safety.


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## Hellkell (Jun 23, 2019)

I always considered putting some Ospho in my compressor. That should help considerably.


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## Superburban (Jun 23, 2019)

Hellkell said:


> I always considered putting some Ospho in my compressor. That should help considerably.


The tank, I hope.


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## pontiac428 (Jun 23, 2019)

Hellkell said:


> I always considered putting some Ospho in my compressor. That should help considerably.


Ospho would bed cheap and easy. Followed with some enamel it should be good for the long haul.

Edit:  Probably should degrease the heck out of it first.


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## C-Bag (Jun 23, 2019)

jdedmon91 said:


> Here is what happened to mine
> 
> 
> 
> ...


I can see the logic of putting a compressor outside. But he doesn't say if he ever drained the tank and I didn't see one. To me that's outta sight, outta mind. I don't leave my old IR plugged in and it's set at 125psi. And I drain it every use. I've never seen rust come out of it. I do think putting some water soluble oil periodically is sound advise as I've had engines that got rust started in the cooling systems and ate the headgaskets away because of it and the only thing that stopped it was water soluble oil.


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