Philip Poburka on fri 8 dec 00
Dear Lowell,
and all,
As it happens, the potential for Rupture of hi-pressure pnuematic containers
(or their Pipes and lines)is very much a 'danger' worthy of reflection, and
Mr. Baker, and Mr. Finkelburger are variously wise to direct our attentions
to that possible eventuality.
These things CAN happen, and sometimes 'do', and unless one has considerable
reflective or reminiscent occupations to get 'caught-up-on' whilst in
traction, some easy precautions, and pointers, may be useful to inform and
dispell our very reasonable concerns and worries.
Air Tanks can and do rust from within. Compressors have usually a little
'drain-plug' or valve (if a 'plug', put IN a 'valve')for the condensation to
be let out. It is a nice thing to have one's Compressor set up so that there
is a little 'tilt' even, on the horizontal ones, so the lowest point favors
the 'plug', or valve for letting the condensation out.
One 'should' drain off this Condensation maybe every few days, or every
week. Depends on how much one runs the thing.'Drain' it with plenty of air
behind it to dehydrate the interior - or that's what I do, anyway.
A 'new' so-to-speak 'cheap' Compressor, can, with a few years of neglect
(ie: not bleeding off, or draining the Condensation) become a pretty
effective pnuematic 'bomb', capable of presenting a memorable surprise for
young and old alike.
A hi-grade used Compressor similarly 'neglected' might take (or have taken)
several (or many) decades to approach a similar potentiality...and some of
them do.
I've been around some which dated from when the Tanks were riveted-up, and
they been chuggin steady maybe eighty ninety years...and not with the very
'best' of 'care'...but with 'enough' care. "Care" ...is sweet.
One may, for a nominal 'fee' take a compressor Tank to places that do
'Hydro-tests'(usually for 'Fire-Extinguishers' or Propane Tanks) and have an
evaluation performed which will establish that the TANK presently is happy
to hold two, or two hundred and twenty-five pounds, or whatever, and have a
'pop-off' valve set to something lower than that, and
drain it now and then and enjoy the darned thing. That and keep the Oil nice
(in the Crankcase), and be glad you have it to help you with your tasks.
One can clean out the Tank of a compressor with at least soap and water and
some gravel or similar, especially if there is a way to 'shake' it - this
will 'scour' things some, light Acid washes may also be done with 'care',
(or 'hired-out') then neutralized...and certain Industrial 'coatings' may be
introduced which (in theory) will protect the Steel Tank from further
rust...before, or after that, do your 'test, or have it done.
(And if you are in a mood to, 'do' it again in ten or twenty years.)
That or just borrow, or 'put' a gauge on it that reads up to several hundred
pounds, plug off the 'pop-off' and fill the Tank maybe 95 percent with water
- watching from a distance - let 'er pump up to maybe two hundred or
so,(this won't take long!) then ('from-a-distance')shut 'er off, and let 'er
sit a while. Heck, let 'er sit a day or two even.
Do this (if you want to!) somewhere, where if she 'blows' there will be
minimum regrets from mishap. With all that water in it, it won't 'blow' near
so bad as it would have if 'full' of air.
If it was to do anything, it would split a seam maybe, or push out some weak
spot a little bit. The pressure will 'drop' VERY fast.
If a 'bad' Tank, you can get another Tank somewhere, satisfy yourself that
IT is 'good' and put your 'Compressor' and motor elements on it, and be
fine.
The 'Compressor' and Motor parts actually do not even 'have' to be 'on' the
Tank anyway...remote Tanks are fine...hooked up by lines or hoses.
Hot water Tanks, big 'Hi-Pressure' Gas cylinders, Old 'Propane' Tanks all
are (IF in 'good' condition) willing to store or hold Compressed Air just as
nice as you please. And at one hundered and twenty five pounds of pressure,
they won't even feel like they are 'workin' after their old accustom'd
duties, they'll think they are on 'vacation'.
Drill, 'tap' and install a nice valve if needed to DRAIN OUT THE
CONDENSATION with any of these set-ups...Or have 'em 'up-side-down' with a
bleeder in the line below them, with a water collector...plenum...(make sure
they are 'hollow'! as Acetylene jugs and some others I think, are full of
clay...)
If happy with that, then you will be good for a hundred and twenty five
pounds set on your 'pop-off' in perpetuity.
You can test your 'pop-off' valve by having a decent gauge on the compressor
Tank (anyway), and just see if she 'pops' when the gauge says what ever your
choice is...hundred pounds, hundred and twenty-five.
Old style 'pop-offs' were often adjustable...I suppose modern ones are too,
or some are.
The 'Condition' of an apparatis or Machine, is a 'Consideration' far more -
I think - than that 'poor' condition is necessarily implicit with 'Age'. To
evaluate the condition, is to exercise our imagination, and our new or
practiced knowledge,(or that of our 'friends'), and to 'find-out'.
All the 'Old' Compressors (some of them 'flat-belt') that I have been around
were quite good. Their actual 'equivelents' in the modern 'lines' would be
very expensive indeed. The 'Old' ones
(do I sound 'biased'?) were often a delight of materials , form and
engineering, and were calculated to find admiration from an audience which
was more descerning and demanding than now-a-days.
I have an old 'Curtis' - 'flat - belt' made about 1928 that was used to
paint Aeroplanes, when Aeroplanes still looked good, and were SOMETHING to
'write home about'. Haven't 'seriously' run it yet, but it is 'sweet'...and
I expect it to be a joy. It pleases me that it used to earn it's keep
painting 'Planes...I like that.
It is 'portable', and weighs maybe three - four hundred pounds.
Will set 'er up on '5.50 - 18' tires...an' tow it now and then.
That and a Big ol' horizontal "Ingersoll-Rand" made in l952 that likewise is
very sweet. You can have a conversation right next to it while it's chuggin'
- it is 'quiet'...80 gallon I think...and 'comes-up' nice as you please.
....Tank was full of rust and sludge when I got it...I have only 'test' run
it so far, and I'll take 'er outside sometime and let 'er chug up to maybe
two hundred or so, and if she passes that ok, then I'll bring 'er back in
and set 'er up for maybe one hundred and twenty-five, and we'll all be
happy.
If it bursts and 'launches' over the roof,(all five or six hundred pounds of
it) or onto my landloard's Car, then I'll have a good time laughing (or
'making' solomn faces for the benifit of others...) AND a good story for my
buddies to get a chucle out of.
Maybe I'll 'chain 'er down'...just to be 'prudent'.
Or best of all...fill 'er ninety-five percent with gool ol' WATER, and be
quite 'considerate' indeed. 'Do my test'.
Many 'modern' ones are noisy, and one WANTS to keep them 'outside'...and
that ought not encourage 'neglect'.
If you 'have' one, or 'get' one Take Good Care of it!
So...'think'...learn about this stuff - it is 'fun'!
And with that...you may make good decisions...learn about what you are
looking at...use them with respect, enjoy them...they ARE a 'blessing'!, and
maybe with affection too, take 'care' of 'em!
"NEW" or 'USED' or even 'OLD'...the condition and the intrinsics of the
engineering are where it's at.
Do not use 'PVC' for air conduit.
Use honest 'Gas-Pipe', or even Water-Pipe, or even Copper pipe silver
soldered.
Hi-Pressure 'rubber' lines are wonderful for extremeties, and
tools...plugging IN to sturdy 'Lines'(as above).
"Cheap" is seldom as 'fun' as 'good'...and 'good' or even "GOOD" are a
function, not of 'price' but of your wit, and knowledge, and maybe elbow
grease...to 'see' it, or make it so.
"GOOD" - insurpassibly so, is possible for the same (Dollar) 'price' as a
'bad' nasty modern cheap outfit.
I am 'in-to' my Big ol' "Ingersoll-Rand" less than a bottom of the line 20
gallon from 'Home-Club' or similar. I'll put another 'fifty' or so into it,
maybe...'maybe'- and it might not 'need' that much. Mostly, just to
'test-it', sandblast and paint it up nice, and new Belts...thats it.
Be 'good' for a hundred years.
Dave Hendley's 'East Texas Special' is as traditional as a nice big slice of
Apple Pie, and every bit as wholesome and heart-warming.
It'll probably last for ever, and be fun the whole time...and 'it' is 'his'.
And...it is 'good'.
Re-read Vince's Posts!
'Cast-iron' versus 'alloy' and these somewhat ephemeral 'teflon' dry
'bearings' etc...'Oil'...
'All' to-a-purpose.
We are fortunate to have this Community!
Happy Pnuematics,
Phil
in Las
------Original Message------
From: LOWELL BAKER
To: CLAYART@LSV.CERAMICS.ORG
Sent: December 7, 2000 1:55:37 PM GMT
Subject: Re: Air compressors kill
I have know one person who got killed from a compressor
explosion and another who was seriously injured.
Do not screw around with compressed air.
Do not buy used compressors.
Service your compressor regularly. This includes draining the tank
and inspecting hoses and tubing.
As most of you know I love appropriate technologies, but this is a
little like finding the parts to build an airplane to fly a few hundred
miles.
New compressors are pretty cheap when you consider the
alternatives like burial expenses, hospitalization, permanent
injuries, loss of work time and not being able to visit this list.
Lowell
The University of Alabama
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