air compressor inspection plug removal

[coeperc]

This is the easiest way I found to remove stuck 2" inspection plugs in an air compressor. I have a 1967 Kellogg American and these plugs would just not move. They had obviously not been removed since installation back in 1967! I tried heat with Acetylene, a 3 foot breaker bar and sockets, and an impact gun and could not get them to move at all. I also tried tightening them first to break them free as that will sometimes work, but no luck. So, I ended up drilling several holes along the perimeter close to the threads and they finally came out! My next step if the holes didn't work was to use a sawzall to cut the plugs in half, but I was afraid of going too far with the saw and into the threads on the tank. Luckily I didn't have to use the sawzall at all! By drilling the holes I had more control with the placement of the drill so as not to get into the tank threads. In case you are having problems removing your plugs, this is the way to go! I've also learned a lot about measuring NPT threads, here is a good chart: http://www.engineersedge.com/hardware/taper-pipe-threads.htm

Now I need to decide if liquid PTFE sealant will work better than teflon tape when re-installing new plugs. Anyone have any advice? Would no sealant at all be preferable?

-Matt

 

[sberry]

Was something telling you not to mess with it? My neighbor essentially ruined a tank after reading a few forum posts, was nothing wrong with it to start with.

 

[coeperc]

No I had to get them open as the tank needed to be cleaned out. I've done enough of this kind of work to know when I 'might' have a chance at ruining something and I knew that would not happen.

-Matt

 

[CNGsaves]

Did you use boroscope to check out inside looking for rust damage??

What did you find??

You going forward with hydro or ultrasonic test ??

Please don't tell us you've got pin hole leaks and trying to weld it !!

Thanks for posting info on your methods to remove ********* plug . . . and Welcome to GJ !

Update your GJ Profile with City / State / Country.

 

[Jswain]

This is when it is nice to have access to hammer wrenches and 48" pipe wrenches with as much snipe as required. Glad you got them out!

 

[coeperc]

Yes I did use a boroscope first. Saw lots of oil and gunk and knew I needed to get the plugs out. Rust is not very bad (thanks to oil coating the tank I suppose!). There are no pinholes and nope I'm not doing any welding to the tank. I may have it hydro tested but doubtful. This was removed working fine from an auto shop so I'm not too worried about it, just want to get it all cleaned out and the pump overhauled. The air intake filter looks as if it was never cleaned or replaced in 30+ years so I'm sure working in a very grimy and dusty auto shop led to lots of dirt and **** getting into the tank.

-Matt

 

[CNGsaves]

Sounds good. Good luck restoring the compressor back to top shape.

Start a thread for your work on your 1967 Kellogg American . . . . GJ loves PICS showing off great compressors being brought back into their prime.

 

[sberry]

I have holesawed plugs out also.

 

[Packard V8]

Now I need to decide if liquid PTFE sealant will work better than teflon tape when re-installing new plugs.

FWIW, my father was a union pipefitter/steamfitter and he used both tape and liquid sealer. He never wanted to see a problem in that particular joint again.

jack vines

 

[tdkkart]

I'm not sure what sort of problems a bit of rusty/oily gun in the bottom of the tank will cause, unless it getting stuck in the drain valve. Bore scope really tells you nothing because you can't tell with any accuracy how much wall thickness has been lost.