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LILGUY
04-20-2011, 06:24 PM
My home is plumbed for 125 psi air from an industrial compressor in my garage. Why is it
necessary to purchase a oil free one for the Shoebox? Thanks

redlaser666
04-20-2011, 06:45 PM
My home is plumbed for 125 psi air from an industrial compressor in my garage. Why is it
necessary to purchase a oil free one for the Shoebox? Thanks

That is nice, you should be perfectly fine using that. Just install a drier/regulator on the output line near the shoebox and set it to about 90psi and you should be set.

I wish I had a big compresor plumbed though my house :(

TomKaye
04-20-2011, 08:42 PM
We do not recommend using an oil compressor with the ShoeBox, only oil-free. If oil mist gets into the system it could explode the tank and kill you and your family. It has happened before, you have been warned.

Tom Kaye

LILGUY
04-20-2011, 10:43 PM
Thanks.Does the high pressure set off oil fumes? Any other worries about explosion? I plan on setting all this up in my Gun/Reloading room. Do not want a grenade going off in there. I'll get an oil free rig and plumb it separately.Those pumps are helatiously noisy.

TomKaye
04-21-2011, 05:16 AM
You should always be concerned when dealing with pressures in the thousands of lbs. Always use rated fittings and hoses, watch out for any contamination. I dont know what you mean by high pressure setting off oil fumes.

Tom

LILGUY
04-21-2011, 06:06 PM
Diesel engines are compression ignition systems, raise the pressure high enough on atomized fuel and it ignites without a spark ignition. What was causing the pumps to explode, oil fumes and 3000 lbs of pressure?

TomKaye
04-21-2011, 11:03 PM
Yes it will ignite just like a diesel engine. Same principle, higher pressures.

Tom

LILGUY
04-22-2011, 08:55 PM
I understand, thanks.

SiliconOrb
04-23-2011, 02:30 AM
Yes it will ignite just like a diesel engine. Same principle, higher pressures.

Tom

I'm failing to grok some things related to this concern.

The most common "White Lithium Grease" one will find in the wild is one by Panef. The datasheet is here (http://www.panefproducts.com/pdf/MSDS%20WGA-6.pdf)

It shows "mineral oil', as an ingredient that has a flash point of 320 degrees f. It is also inevitable that some of the grease will find it's way into the high pressure areas of the compressor.

So the question burning in my mind is "why does this not pose a similar explosive risk", considering that it is a source of ignition, or fuel, just like other oil? Is there a petroleum-free or non-flammable "white lithium grease" that one should be using, instead of the very common hardware store variety?

TomKaye
04-23-2011, 03:25 AM
Its the mist that tends to ignite. The solid grease makes it more difficult.

TK

SiliconOrb
04-23-2011, 04:14 AM
Its the mist that tends to ignite. The solid grease makes it more difficult.

I get that part. I guess the thing I don't quite understand is how oil mist can remain a mist through 2 separators and 40 feet of air line and hoses. I know there are machine oilers which create this mist intentionally, and that's even a challenge over that distance with no separators. Also, the one instance I have heard of an HPA tank exploding was attributed to liquid oil residue, not a "mist" (the White lithium really isn't a "solid", BTW, especially since it's often separated right out of a fresh tube.) It's also not entirely unlikely that any liquid ignition material would be immediately atomized when the high pressure air rushes past it rapidly, as that is, after all, how a liquid gets atomized.

I understand that there is a need to CYA legally, but I'm having a hard time believing that a well filtered air supply over a long distance from the pump is any riskier than the risk inherent in the lubrication used on the Shoebox itself. Regardless, I think folks need to understand the reasons these explosions occur, and take proper precautions no matter what the air source. The sudden inrush of high pressures to a low pressure container is primarily what creates the high temperatures which cause ignition, so all containers should be filled SLOWLY. I saw at least one reference state that one should not exceed 200psi per second fill rate for this reason. Also, safety dictates that folks should make sure that there is no contamination of any sort in any fill lines. Even dust can ignite and mix with all that oxygen to create an explosion.

TomKaye
04-23-2011, 07:06 AM
Well you make many good points but my lawyer will still not let me say anything but "NO OIL". What you do is up to you.
TK