Neglected 60gal compressor repair+testing (Quincy QE-5 1989)

[FliesLikeABrick]

For what it's worth/to close the loop with the group here - after further inspection of the tank, I have decided to try and track down a new 60 or 80 gallon tank that I can transplant all these parts over to.

 

[extropic]

For what it's worth/to close the loop with the group here - after further inspection of the tank, I have decided to try and track down a new 60 or 80 gallon tank that I can transplant all these parts over to.

You successfully hydrotested it to 240 PSIG. What further inspections did you perform and what were your findings that lead to your decision to replace?

I'm not criticizing your decision. I (and I assume others) might learn something from your inspection and decision processes.

 

[FliesLikeABrick]

Thanks for asking --

When I had drained water from it previously, including after hydrotesting it, the tank drain at the bottom kept becoming clogged with pieces of rust or other debris. I decided to stick my cheap borescope in one of the tank openings and take a look, and saw two things:
- The walls of the tank near the bottom, particularly the welds, didn't look great
- There was so much sludge (presumably 100% rust debris) that I couldn't even find the tank drain at the bottom

I ended up hooking together a bunch of fittings to feed water in, agitate it, and drain out the bottom of the tank. After doing this with probably 30 gallons of water, I finally got it to run clear -- but not until I had a *lot* of pieces of debris come out with the rust. Presumably the rusting was more than just surface rusting inside over time leading to rusty water/discharge... but actual solid pieces of rust that made me think bigger pieces were flaking off.

Here are pictures:

junk in bottom of tank before flushing (borescope):



more of the same, notice the larger chunks. These were large enough to clog the 1/8 NPT boss at the bottom of the tank, even after I removed the fittings





Some of the junk in a bucket after pouring the water off:

 

[Flyinfool]

Are there places to find used 60-80 gallon tanks that are safe? New ones are so expensive.

 

[FliesLikeABrick]

I found a surplus site online that has them new at a reasonable price, but the freight is the killer. I'm working on trying to find a local business that will let me have it delivered to their place (and drop it in my truck with a forklift) for $50, so that I can save $180 of the freight charge by not needing a liftgate and delivery to a residential area.

 

[matthewsx]

I bow to greater experience when it comes to deflecting fragments although I still believe that some obstacle is better than none. I expect the real key would be running it a lower than spec pressure. Considering that the tank was probably tested at over 200 lbs of pressure, running it at 125 or so would likely be fine. I would certainly do so with that setup.

I have an older compressor I got from a customer. After talking with the local compressor shop I dropped the max pressure down to 125psi and don't really worry about it.

Yes, they are horrible when the let go but it's a lot more likely with a horizontal tank (more area exposed to water) than a vertical one.

I would run it outside if that's possible with your setup just because it's nicer.

John

 

[lordbeezer]

I cut a lot of compressor tanks open to make grills,smokers. Some are scary rusted thin. Lots of big chunks of rusted metal. I think you made the right decision. Tank would make a good smoker or grill

 

[extropic]

I found a surplus site online that has them new at a reasonable price, but the freight is the killer. I'm working on trying to find a local business that will let me have it delivered to their place (and drop it in my truck with a forklift) for $50, so that I can save $180 of the freight charge by not needing a liftgate and delivery to a residential area.

Perhaps you could have the tank delivered to the carriers terminal nearest you (save the $50 and the LTL freight should be the lowest possible). Find out which carrier the seller will use and see if their nearest terminal makes sense for you. They have always loaded onto my pick-up. YMMV.

 

[FliesLikeABrick]

Perhaps you could have the tank delivered to the carriers terminal nearest you (save the $50 and the LTL freight should be the lowest possible). Find out which carrier the seller will use and see if their nearest terminal makes sense for you. They have always loaded onto my pick-up. YMMV.

Thanks this is an option I had not considered

 

[rwm]

If I ever build my dream shop, I am going to plan on a metal cage to situate the compressor and the dust collection vacuum in a separate closet.
If you watch the video of catastrophic tank failures they do not seem to fragment. More like one or two large flaps of sheet metal to contain.

Robert