Leaving air compressor full of air

Discussion in 'Tools and Materials' started by iwaters, 20 Sep 2010.

  1. iwaters

    iwaters

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    Is it safe to leave an air compressor full of compressed air or should I empty the cylinder when I have finished with it?
     
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  3. Stivino

    Stivino

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    It must be safe because it's designed to withstand pressure. I leave mine full with the air valve closed when I'm finished with it, so that there's instant pressure the next time I use it. None of the places I've worked in, that had compressors, released the pressure at the end of the day.
     
  4. Richard C

    Richard C

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    If you use the compressor infrequently I would advise you empty the cylinder when you’ve finished. Whilst it is quiet safe to leave the cylinder under pressure, a by-product of compressing air is water; the pressure will most likely drain away after a few days anyway but the water will sit in the bottom of the cylinder & cause internal corrosion.

    I use my 10 cfm unit infrequently & always leave it with the drain cock open; if used every day, a drain down one a week is OK.
     
  5. joe-90

    joe-90

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    Richards right. Richard's the daddy. It's the water that is the issue.
     
  6. sparkiedave

    sparkiedave

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    I'd also be a bit more wary if you use air fed breathing gear, stale damp air that has once been warm isn't a good thinhg to be breathing in
     
  7. Stivino

    Stivino

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    Whilst water is an issue, it's more of an issue to the air tools being used than the inside of the receiver. Even if you do drain the receiver daily/weekly etc.the inside of the receiver will still be damp.
    I drain mine before I use it, and, in the fifteen years that I've had it, I'll bet the total amount I've drained from it will be about 10cc of water. Even if you do keep the pressure in it, you should be able to keep the water to a very little amount.
     
  8. ColJack

    ColJack

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    I suppose it would depend, if it's a compressor for your garage etc then I can't see the harm, if it's in the back of a van going from place to place then empty it just in case..
     
  9. mattylad

    mattylad

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    NO wonder I'm short of breath, you buggers have got the air all hidden away in your compressors :D
     
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  11. Richard C

    Richard C

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    I suppose it depends on what compressor you have & if it gets any serious use but you should never run air tools without an in-line filter/regulator; they are not expensive but your air tools will have a very short life if you don’t have one; & don’t even think about paint spraying without one.

    10cc was a band & a very good one at that; I assume you mean 10cl ;) . You should drain the tank AFTER you use it not before; if you leave the water in there it probably accounts for why you’ve seen so little when you drain it, it’s already converted to ferric oxide inside your tank! Either that or you have a very small compressor.
     
  12. Hitachimad

    Hitachimad

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    Unless you have perfect pipes/fittings/valves, it will probably empty itself over a few days anyway. You should probably drain it down to prlong the life of the pressure gauge. I dont know anyone that bothers :LOL:
     
  13. Richard C

    Richard C

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    How does that drain the water residue from the bottom of the pressure vessel :confused:

    Prolong the life of the pressure gauge :eek:

    How many do you know then :?: have you ever owned/worked in a professional machine/work shop. ;)
     
  14. Stivino

    Stivino

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    I drain it before I use it to make sure there is no water getting into my tools. If I drain it beforehand, I know it's empty during use. It gets very little use, I only use it a couple of times a year.
    And, I meant 10cc, as in 10ml or 10cm³.
     
  15. Hitachimad

    Hitachimad

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    Open the drain tap on the receiver :rolleyes: and drains at lowest points on pipework.
    I didnt mean draing the water, i was talking about the pressureised air.


    Applies to a regulator setup, having the regulator under contant pressure will reduce its accuracy over a long period of time. Draining down pressurised systems when not in use is what is supposed to be done.

    And yes, most working days for some years now as it happens. Again, i'm talking about air NOT water. :rolleyes:
     
  16. Richard C

    Richard C

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    That’s what I already advised; you said no one bothers :rolleyes:

    Well that’s obvious but it’s the build up of water in the receiver that will cause most problems, not leaving the receiver full of air under pressure which, as weve both said, will drain away.

    I agree & is what I originally recommended.

    We seem to have got a little crossed up here but now you’ve made your post clearer, it does make more sense. ;)
     
  17. Burnerman

    Burnerman

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    I drain mine about once a month - and get a fair bit of water out. I usually do this with the tank under pressure and after the water has bled out, I remove the drain cock, set the thing going and blow out any excess that way - I can just about lift one end up to allow the water to flow.
    The water that comes out has a rusty tinge and no doubt, some day the tank will give up the ghost.
    Can anyone recommend quality 10mm hose with 1/4 BSP ends? machine mart stuff is very poor.
    John :)
     
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