Air compressor project

[Al Strachan]

yup, you've nailed that! well done

 

[Sam0117]

Small update

managed to get the pressure switch done, nothing really wrong with this just a clean up an paint and reassemble, I tried to paint the detail plate but it’s not fully flat so I took the paint back off and it’s looks alright…… next step the tank, this may take me awhile lol

 

[Sam0117]

So a long overdue update. been 5 months but with work and young kids don't get a lot of time to work on my own stuff but I'm in no rush so bear with me.

So the tank is a big part and I wanted to do it right, the biggest problem I faced was the amount of old oil and water and rust in the tank.

So the bottom left of the picture is the bottom of the tank, the tank is currently on its end hence why the lose oil and water is at the very end but all that rust build up got me worried this tank maybe scrap. I was thinking of different ways to clean the inside of the tank as best as possible and as cheap as possible, spoke to local tank refurb company who said they would cut one end open to clean it out and the reweld the end back on, yeah as you can bet they was expensive (most likely just for me to say no). obvious access was hard as the end ports are only 2". I drained the tank of all the old oil in old oil drums and got ride via a friend, I've mentioned him previously. now how best to clean the rest of the rust out, I saw an interesting video of a guy using electrolysis to clean a small air compressor tank out and I was settled on that, cheap easy and I've never done it before so was interested to see how it worked.



I managed to get hold of some scrap aluminum profile from work and a couple of brackets to build a frame that would hold up the tank vertically to make this easier for rigging up and eventually cleaning and painting.



I plugged off all the ports barring the top and the bottom I put a 1/2" ball valve to allow me to drain the tank afterwards. Borrowed a battery charger from my dad and brought some washing soda from the shop and I was set. filled the tank with water and put the sodium carbonate in a separate bucket to dissolve before I put it in the tank. Had a piece of 1" square tube to use as my anode ( cant remember if it cathode or anode ) hooked the positive up to the 1" and the negative to the body of the tank and lets the process run.

I had a quick check after 15 minutes just to see if it was working


Looking good, I gave it 24 hours and came back to see this.



I was blown away, wiped the rod clean and put it back in, repeated this every 3-4 hours from this point until I was happy, gotta admit I was very surprised at how the tank turned out, ill take a pic next time I'm in the garage.
Draining the tank was a pain I'll admit as bits of rust managed to keep blocking the hose tail so that took awhile but it was well worth it, got the jet was inside as best as I could and blast the remaining rust off, I would recommend this for anyone who wants to try it. now the tank is as clean as I could possibly get it next job was to pressure test it as the tank is from the 60's and I don't want it to explode in my garage.

 

[Sam0117]

Now according to the tank tag is was pressure tested to 300psi back in 1960, and for my own sanity I wanted to do my own to make sure its all good and not scrap now all that rust and crap is out of it.


Blocked all the plugs and filled it up with water ready to test, I managed to borrow this testing unit from my old work which they hadn't used for a while so I was a bit worried about the gauge on the unit so I put a smaller pressure gauge on the tank just to double check the unit one was ok, they were spot on so took my little one off and went for it, and I had a leak at just under 200psi, luckily it was a plug leaking had to drain the whole tank to undo the plug and reseal and then fill back up again, got to 300psi, it this held for 20 minutes so SUPER HAPPY . had a slight weep on another plug so it dropped a small amount



I'm gonna call that good and as it'll never go above 8-9 bar so its nice an safe, cant beat how they built things like this, now I've got the fun of stripping the paint off and repainting, one step closer to being done .

Hopefully the next update wont be 5 months but we shall see.

Hope your all well and thank you again for reading my progress.

 

[GraemeVW]

Interesting on the tank test.
I just did the same as you with a 1975 broomwade, but without the 're paint.

Tank had slight rust inside but is very thick and looked good.
Not took it over 90psi yet though as I really don't want it to explode!
I had been wondering about a home done hydraulic test.
Can you tell me more about the pump?
Not sure how I can create the needed hydraulic pressure.

 

[brightspark]

it wont explode . if it was badly corroded it would pinhole at the bottom and you would hear a slight hiss of air or it would pee a bit of water out if there was any in under pressure

 

[GraemeVW]

it wont explode . if it was badly corroded it would pinhole at the bottom and you would hear a slight hiss of air or it would pee a bit of water out if there was any in under pressure

Deep down I know I'm over thinking it and worrying too much.
From what I've read tank explosions are normally thin tanks and flammable gasses inside the receiver igniting.
Don't think ive ever seen pics, or a report, of a tank that has exploded due to rust.

Still want to put it outside before I turn it up to its 150psi working pressure though

 

[brightspark]

a 1 gallon oil can with crimped ends on can go to 50 psi pressure before the ends fly off and it bursts open

 

[GraemeVW]

a 1 gallon oil can with crimped ends on can go to 50 psi pressure before the ends fly off and it bursts open

Thanks for the perspective.
I'll stop spamming OPs fantastic resto now!

 

[brightspark]

the only thing i have had burst was about 4 air hoses .they blow up like a balloon then let go. it puts the sh....its up you when they go off quite close and dont expect it

 

[GraemeVW]

the only thing i have had burst was about 4 air hoses .they blow up like a balloon then let go. it puts the sh....its up you when they go off quite close and dont expect it

If I could post emoji, you would see I'm laughing!

 

[daleyd]

Just had a read through this, good job !!

I can confirm J&E Hall are still going, I did a job with them for a pharma company over in Ireland last year, they supplied 2 massive chillers for the entire facility (can’t remember off the top of my head but I think the motors on each one were something like 700kw?? Will have a check through the docs next week when back in work)

 

[Bornfree]

Just had a read through this, good job !!

I can confirm J&E Hall are still going, I did a job with them for a pharma company over in Ireland last year, they supplied 2 massive chillers for the entire facility (can’t remember off the top of my head but I think the motors on each one were something like 700kw?? Will have a check through the docs next week when back in work)

I did my refrigeration training at j&e hall at Dartford

 

[Sam0117]

Interesting on the tank test.
I just did the same as you with a 1975 broomwade, but without the 're paint.

Tank had slight rust inside but is very thick and looked good.
Not took it over 90psi yet though as I really don't want it to explode!
I had been wondering about a home done hydraulic test.
Can you tell me more about the pump?
Not sure how I can create the needed hydraulic pressure.

The pump is a rothenberger pump

Manual Hydraulic Pressure Test Pump 50 Bar for Pipeline Container Irrigation UK | eBay

Find many great new & used options and get the best deals for Manual Hydraulic Pressure Test Pump 50 Bar for Pipeline Container Irrigation UK at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

that’s a link to one that’s similar, in honestly I’m glad I tested it just out of peace of mind. And like you said I’ve never heard of a air receiver exploding unless it’s new thin one but this thing is heavy, thanks for saying it’s fantastic, I’m trying to do my best with what I’ve got available I know it could be better but that’s time an money I don’t currently have.

 

[not done it yet]

it wont explode . if it was badly corroded it would pinhole at the bottom and you would hear a slight hiss of air or it would pee a bit of water out if there was any in under pressure

You only need to watch the accidents shown on youtube to understand that they can fail catastrophically - and make a big mess when they do.

Here is an example :

Insurance companies would not bother with regular tests/checks if they always failed safe (a small leak).

A pump is good for testing. I used a grease gun to test mine the first time (about 30 years ago). A hydraulic press pump can be used (the oil used is not important) or a bleed from a pressure washer is often the pressure source. The grease gun was slow - any air pocket, however small, needs filling and the tank will expand as the pressure rises, but it got there.

 

[GraemeVW]

The pump is a rothenberger pump

Manual Hydraulic Pressure Test Pump 50 Bar for Pipeline Container Irrigation UK | eBay

Find many great new & used options and get the best deals for Manual Hydraulic Pressure Test Pump 50 Bar for Pipeline Container Irrigation UK at the best online prices at eBay! Free delivery for many products.

www.ebay.co.uk

that’s a link to one that’s similar, in honestly I’m glad I tested it just out of peace of mind. And like you said I’ve never heard of a air receiver exploding unless it’s new thin one but this thing is heavy, thanks for saying it’s fantastic, I’m trying to do my best with what I’ve got available I know it could be better but that’s time an money I don’t currently have.

Everything could always be better. That's what makes us strive to achieve.
When you stop thinking things could be better you may as well give up.

 

[GraemeVW]

You only need to watch the accidents shown on youtube to understand that they can fail catastrophically - and make a big mess when they do.

Here is an example :

Insurance companies would not bother with regular tests/checks if they always failed safe (a small leak)

Yeah, but look how thin the tank is!
It doesn't look particularly rusty inside either. So just a poor tank, hugely over pressure, or explosive gasses inside?

The vid may explain, but I can't really watch it right now.

 

[Sam0117]

Just had a read through this, good job !!

I can confirm J&E Hall are still going, I did a job with them for a pharma company over in Ireland last year, they supplied 2 massive chillers for the entire facility (can’t remember off the top of my head but I think the motors on each one were something like 700kw?? Will have a check through the docs next week when back in work)

Thanks Daleyd, man 700kw that’s a lot of juice, would use a lot of space in my tiny garage to get that in lol

 

[brightspark]

You only need to watch the accidents shown on youtube to understand that they can fail catastrophically - and make a big mess when they do.

Here is an example :

Insurance companies would not bother with regular tests/checks if they always failed safe (a small leak).

A pump is good for testing. I used a grease gun to test mine the first time (about 30 years ago). A hydraulic press pump can be used (the oil used is not important) or a bleed from a pressure washer is often the pressure source. The grease gun was slow - any air pocket, however small, needs filling and the tank will expand as the pressure rises, but it got there.

thats ******

 

[daleyd]

Thanks Daleyd, man 700kw that’s a lot of juice, would use a lot of space in my tiny garage to get that in lol

Yeah they did sound pretty hefty, though I worked on the job for about 3 months and never saw anything more than a whole load of documents and some screens on a computer system that I drew for them!! I never got to see it actually running