POTD- PROJECT OF THE DAY: What Did You Make In Your Shop Today?

Nice compressor, but how is the tank? Have you checked the wall thickness at the bottom or checked for corrosion thinning of the tank?

Dependant on that, consider derating it a couple bar. Old air tanks = Trouble due to unknown history unless properly inspected.
 
Braeden P said:
I picked up a 120 gallon air compressor a few weeks ago. It’s rated for 20CFM at 125PSI and weights over 1,500lbs. It had a bad 5hp baldor so it was super cheap. It’s got an ingersoll rand 253 two stage pump. The thing is massive. I’ve got a 7.5hp three phase with the same RPM so I’m throwing that on it. It’s got the same exact bolt pattern luckily but I did need to bore the pulley out slightly. I wired up the contacter but still need to connect the motor. 5lb dead blow for scale. I like the look of it with the new motor over the finless baldor.View attachment 488003
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Can you do a hydraulic water test on the tank?
 
There is sight holes that I will inspect the inside before running it. I drained the water which was about a few ounces with no discoloration. The tank looks horrible on the outside due to a bad paint job. Underneath that is good paint with almost no rust. I’ll see if I can do a hydraulic test on it.
 
woodchucker said:
Can you do a hydraulic water test on the tank?
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Hydro usually go above rated spec by a specific percentage based on rated pressure, then once at that pressure it has to sit and hold that pressure for a specified time without leakdown to prove soundness.

Once that is done, drying the inside of the tank is a bear as is trying to prevent corrosion because normally, the inside of the tank is bare metal.

I was taught, at least on easily portable tanks, to use a (custom made) spray bar through the inspection ports on the end of the tank and spray anti-corrosion product on the inside of the tank walls if it was going to sit for a while not in use to prevent corrosion. Side effect? none. Benefit? a (semi) protected tank.
 
Braeden P said:
I picked up a 120 gallon air compressor a few weeks ago. It’s rated for 20CFM at 125PSI and weights over 1,500lbs. It had a bad 5hp baldor so it was super cheap. It’s got an ingersoll rand 253 two stage pump. The thing is massive. I’ve got a 7.5hp three phase with the same RPM so I’m throwing that on it. It’s got the same exact bolt pattern luckily but I did need to bore the pulley out slightly. I wired up the contacter but still need to connect the motor. 5lb dead blow for scale. I like the look of it with the new motor over the finless baldor.View attachment 488003
Click to expand...
Nice,

You might want to pressure test the tank if you're planning on running at full pressure and will keep it a while. Regardless, change the pressure relief valve. Cheap insurance.

John

Looks like they beat me to it....
 
Why is this an issue? "drying the inside of the tank is a bear". There is always condensate inside a tank.
 
matthewsx said:
Nice,

You might want to pressure test the tank if you're planning on running at full pressure and will keep it a while. Regardless, change the pressure relief valve. Cheap insurance.

John

Looks like they beat me to it....
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Good call on the relief valve.

Always one of the first things to do.

Talking of insurance, in the UK, any pressure vessel over a specific capacity and age (over 500 Bar litres* and 3 years old, but it has been a while since I checked), has to have an annual pressure test and the owner of said tank must have the certificate to gain the required insurance coverage. Not sure on what the situation is outside the UK though?

A pressure tank explosive failure can cause serious damage, injury and even death.

Bar Litres = Tank capacity in litres x Pressure. Therefore a 50 litre tank at 10 bar = 500 bar litres.

1 litre at 1 bar = 1 bar litre, 1 litre at 2 bar = 2 bar litres, 1 litrre at 3 bar = 3 bar litres and so on.
 
rwm said:
Why is this an issue? "drying the inside of the tank is a bear". There is always condensate inside a tank.
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Condensate can be dealt with. filling a tank with water and pressurising it is different.

Drying the tank after a hydro test and using anti-corrosive helps stop corrosion forming quickly. Most decent compressors have a drier between the compressor head and tank to prevent moisture entering the tank to extend tank life and prevent corrosion.

Many people, myself included will fit one if the compressor is supplied without one between the compressor head and tank.

It is about protecting the tank but most of all it is about protecting yourself from the consequences of preventable premature tank failure.

Yes, condensate is a part of life when atmospheric air is compressed. Removing that condensate before it gets to the tank is the difference between a clean tank and one that has corrosion erosion (wall thinning) issues.
 
srfallsallot said:
Hydrostatic testing to 1.5 times the operating pressure is what is required. There are several videos on how to do it. Google. This is not a place to say good enough.
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Absolutely correct. 100%

NEVER take a risk with a compressor tank. If you buy pre-owned, inspect the tank BEFORE purchase (internal visual + ultrasonic wall thickness check + hydro test). If that inspection is refused, walk away. No point in "taking a risk" that it is safe.

I have sold TWO compressors in the last 8 years, both less than 3 years old at the time. Advised the buyers to have tests done BEFORE purchase to ensure safety and as proof there was no shennanigans going on, they did that, had proof tank was ok and purchased the compressors without issue.

I will be replacing my current compressor again next year (like-for-like) so again, I will be sellin the one I currently have.

Long story, but there is a reason behind why I buy new every two or three years.
 
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