In article <[email protected]>, Max
<[email protected]> wrote:
> Is there any consensus on whether or not to use PVC or CPVC for air lines?
If you like the idea of PVC shards being driven about the shop by 150
psi pressure, I say go fer it.
How about nylon tubing? This is similar to what I use:
http://www.wicksaircraft.com/catalog/product_cat.php/subid=1745/
425psi working pressure, 1700psi burst, it connects easily with brass
compression fittings and it's flexible making routing easy. All for
$0.91/ft.
-Brian
Max wrote:
> Is there any consensus on whether or not to use PVC or CPVC for air lines?
> My compressor is capable of 150psi.
> I already have copper for most of my distribution system but I need to add a
> branch and the copper prices are profanity inducing.
>
> Max
On Dec 4, 9:05 pm, "Bill" <[email protected]> wrote:
> PVC that gets bumped becomes a schrapnel (sp?) bomb.
>
Only if you fill the cavity with an explosive mixture.
Air pressure alone will not have that catastrophic an effect.
At worst, the 'shrapnel' will fall at your feet.
Hollywood has completely distorted the concept of 'explosions'.
On Dec 6, 12:35 am, Lew Hodgett <[email protected]> wrote:
> Robatoy wrote: > Only if you fill the cavity with an explosive mixture.
> > Air pressure alone will not have that catastrophic an effect.
> > At worst, the 'shrapnel' will fall at your feet.
>
> BULL SHIT! !
>
Find me one report/link to an accident that didn't involve air
pressures greater than 150 psig or an explosive (oil) mixture.
One!
On Dec 6, 12:10 am, "CW" <[email protected]> wrote:
> Think again. Explosion due to rupture of a vessel containing a compressed
> gas is extremely violent. High pressure gas cylinders are pressure tested
> with a non compressible liquid for this reason.
Don't change the subject with 'high pressure gas cylinders'. Keep the
discussion at shop air pressures of max 150 psig.
And I know that a vessel with 3000 psig worth of steam can level a
generating station. Boilers can throw an entire ship in the air.....I
am talking about 150 psig worth of shop air.
I am talking about a garden hose and you're switching the discussion
over to the Hoover Dam bursting.
Find me an accident report. No explosive gasses.....air. 150 psig max.
I've heard of shops using PEX for air lines. It's really easy to work
with. Not rated for air or areas exposed to sun light, but if it
explodes it won't turn into shrapnel like PVC does.
Max wrote:
> Is there any consensus on whether or not to use PVC or CPVC for air lines?
> My compressor is capable of 150psi.
> I already have copper for most of my distribution system but I need to add a
> branch and the copper prices are profanity inducing.
>
> Max
On Dec 6, 8:40 am, "Mortimer Schnerd, RN" <mschnerdatcarolina.rr.com>
wrote:
> Robatoy wrote:
> > Find me one report/link to an accident that didn't involve air
> > pressures greater than 150 psig or an explosive (oil) mixture.
>
> > One!The very first listing from googling "shop air explosion" revealed one occasion
> where 140psi of air was accidentally put in a truck tire which then exploded,
> killing the worker. No explosive mixture... just air pressure less than 150
> psi.
That's not a shop-air explosion. That is an idiot overinflating a tire.
Using that barometer (I made a funny), I am sure there are many
air-related accidents.
Put 30 psi in your ears, and you'll get hurt. 5 psig through an
intravenous needle into your bloodstream and you're toast. How many
accidents have been reported where somebody has blown dirt into their
eyes? That happens all the time.
Compressed air can hurt you.
I want to see a report where it states that an air distribution line
exploded, pvc, copper. rubber... anything. My old shop has a large 3/4"
PVC airline distribution system. A dozen drops. Never had an issue for
20 years. Had a crimp come off a cheap airline once.. chased one of the
guys around the paintbooth real good.. he had some welts on the back of
his legs and a bruised ego..we had a huge laugh...(Could have been more
serious, we were lucky.. but you need full-tilt air to blow off dirt
particles)
With all due respect,
r
Robatoy wrote:
Had a crimp come off a cheap airline once.. chased one of the
> guys around the paint-booth real good..
which reminded me....
Same guy took a full swing with a #1 wood at a golf-ball in his tiled
bathroom.
33 cuts, 112 contusions and 44 lacerations.
Good thing his roommate heard the commotion and opened the door to let
the ball out.
So, does this mean that my potato cannon constructed out of schedule 40
PVC is now to be considered "unsafe"? I wrapped a few layers of duct
tape around the combustion chamber, just in case of a blow out - no
problems yet.
BTW, I've got a great book on the subject called "Backyard
Ballistics". All kinds of fun projects involving PVC.
Robatoy wrote:
> On Dec 6, 12:35 am, Lew Hodgett <[email protected]> wrote:
> > Robatoy wrote: > Only if you fill the cavity with an explosive mixture.
> > > Air pressure alone will not have that catastrophic an effect.
> > > At worst, the 'shrapnel' will fall at your feet.
> >
> > BULL SHIT! !
> >
> Find me one report/link to an accident that didn't involve air
> pressures greater than 150 psig or an explosive (oil) mixture.
>
Anecdotal only. My boss at my old job had a neighbor
who tired to inflate a space-saver spare tire to 32 psig
or so instead of the rated maximum.
It separated from the rim and the blast of air blew his
face off of his skull.
That's not a terribly good analog to the present discussion.
What size pipe is pretty important in this context.
IIRC, plastic soda-pop bottles are rated for about 150 psig.
So you could take a small one, put some vinegar in it and
then drop in some baking soda wrapped in wax paper,
screw on the cap and put it somewhere safe to see how
big a bang it makes.
Please note, this may be illegal in your locale. If that is
the case, don't do it.
--
FF
Mortimer Schnerd, RN wrote:
> Frank Stutzman wrote:
> > Anybody wager a guess if an exploding 1 inch PVC pipe could go through 1/2
> > inch plywood? The pipes couldn't be hit by anything, but summer heat
> > might soften the PVC to the point it would burst
>
>
> Summer heat will do a lot more than soften PVC; it will raise the pressure of
> the compressed gas.
>
If you've kept the same gas compressed in the same pipe since
winter....
--
FF
Mortimer Schnerd, RN wrote:
> Robatoy wrote:
> >> Robatoy wrote:
> >>> Find me one report/link to an accident that didn't involve air
> >>> pressures greater than 150 psig or an explosive (oil) mixture.
> >>
> >>> One!The very first listing from googling "shop air explosion" revealed one
> >>> occasion
> >> where 140psi of air was accidentally put in a truck tire which then exploded,
> >> killing the worker. No explosive mixture... just air pressure less than 150
> >> psi.
> >
> > That's not a shop-air explosion. That is an idiot overinflating a tire.
> > Using that barometer (I made a funny), I am sure there are many
> > air-related accidents.
>
>
> Look at the first line you wrote above: I met every criteria you asked for.
> Now you're adding conditions?
You did not meet the criteria. You did not point to a situation where
the PVC pipe had exploded... it was a truck tire. The topic here is PVC
piping.
Having said that, I have discovered one of the errors of mine and that
is the air plumbing in the old shop is in fact ABS. My apologies.
I also read the other links that kind Wreckers have posted. I would
never even think of PVC in an industrial application. Service air
systems in my history have been driven by 100 HP rotary vane
compressors at pressures of 300 PSIG and higher. 4" lines are not
uncommon in power generation.
To be blowing craters of the dimensions stated in some of the reports,
one needs a whole lot more than a basic wood-workers' compressor.
Therefore the parallels are ridiculous.
Even though, in one of the reports it states "Gas Transmission and
Distribution Piping Systems Standard, limit the operating pressure of
plastic piping distribution systems to 100 pounds per inch (psi)",
which makes me think that PVC isn't as fragile as some think it is, it
obviously isn't worth taking a chance on PVC. I hereby retract my
careless endorsement of PVC and suggest we stick to copper, ABS or
other stuff I have never heard of before.
Lesson learned, ABS isn't PVC and you can't get anything past this
alert crew of wreckers.
Thanks for the corrections.
r
Leon wrote:
> <[email protected]> wrote in message
> news:[email protected]...
> >
> > Anecdotal only. My boss at my old job had a neighbor
> > who tired to inflate a space-saver spare tire to 32 psig
> > or so instead of the rated maximum.
>
> Moden day space saver tires are usually inflated in excess of 50lbs. I
> suspect his spave saver tire was old and rottten.
Old yes. Not rotten. The original ones were only to be inflated
to 12 psig or something like that. Accidents of the sort described
are why those are no longer available.
Memory dims but I think they were collapsible with the tire folded
into the rim.
--
FF
Leon wrote:
>
> Yes those were the original space savers with a canister of air for filling.
The 2006 Porsche Carrera GT comes with a can of puncture fix. No spare.
Reason being, that there is no room for a spare..even a small temporary
one, but most of all there certainly isn't any room to put any of the
wheel/tires that would come off the car... even when flat. HUGE rear
wheels. (335/30 ZR20 got to get them 600 ponies to the street somehow,
eh?)
Don't need no steeenking spares....
"[email protected]" <[email protected]> writes:
>How about nylon tubing? This is similar to what I use:
>http://www.wicksaircraft.com/catalog/product_cat.php/subid=1745/
>425psi working pressure, 1700psi burst, it connects easily with brass
>compression fittings and it's flexible making routing easy. All for
>$0.91/ft.
There is also DOT air hose used in trucks/buses with air brakes. You can
buy it at any heavy truck dealer and you can also get compression
fittings. The 1/2" diameter should carry enough air for the average shop.
Brian Elfert
"Mike Marlow" <[email protected]> writes:
>> There is also DOT air hose used in trucks/buses with air brakes. You can
>> buy it at any heavy truck dealer and you can also get compression
>> fittings. The 1/2" diameter should carry enough air for the average shop.
>>
>Holy Cow Brian... $$$$$$$$
I just did a quick search online and found 1/2" DOT air line for 71 cents
per foot. This was at a street rod place, so a truck dealer should be
less.
71 cents a foot is a lot less than copper. don't know what black pipe
goes for these days.
There is a 500 foot roll on ebay for 35 cents a foot plus shipping.
Brian Elfert
B A R R Y wrote:
> Robatoy wrote:
>
>>
>> That's not a shop-air explosion.
>
> <http://www.osha.gov/dts/hib/hib_data/hib19880520.html>
With all due deference, the operating pressure of the exploded line was
not given. However, there is no reason for presuming that it exceeded
the pressure under discussion, either. Moreover, further down in the
page a restriction of 100 psi was imposed ... well below your postulated
150 psi.
One of the additional links DID relate specifically to shop-level
pressure and a couple of clearly dangerous failures.
ABS, apparently, ruptures. PVC, just as apparently, shatters rather
dramatically.
Under the banner of erring on the side of caution, would it not make
sense to eschew pvc in favor of one of the other, commonly used, materials?
Your pvc has flexed each time the pressure has changed. That's a lot of
cycles over the lifetime you told us about. The course of prudence would
be to at least shield it.
Bill
Mike wrote:
> So, does this mean that my potato cannon constructed out of schedule 40
> PVC is now to be considered "unsafe"? I wrapped a few layers of duct
> tape around the combustion chamber, just in case of a blow out - no
> problems yet.
>
> BTW, I've got a great book on the subject called "Backyard
> Ballistics". All kinds of fun projects involving PVC.
>
When I worked for the railroad the car knockers would drop a lit fusee
into a pipe they had rigged up to a glad-hand and kick the valve on the
ground air open.
Probably got a good 100 ft or so altitude ... maybe twice that
horizontally.
;-)
I think that they used them to signal each other. The fusee goes out
when it strikes anything hard (a gentle sideways tap is sufficient to
extinguish them) so they are actually pretty safe for that use.
Bill
"B A R R Y" <[email protected]> wrote in message
news:[email protected]...
> Mike Marlow wrote:
> >
> > Lots of guys want to do spray painting and that kind of delivery
capacity,
> > especially with smaller compressors, will hurt their efforts.
>
> Mike, I have spray painted with that setup. <G>
How much? I have to admit that I tend to think in bigger terms than
woodworking, owing to the type of painting I do, so that's my shortcoming in
a discussion like this. I suppose for typical small scale painting it could
be ok.
How much small diameter hose do you have in your delivery system? Do you so
small scale spraying? Are you getting good atomization and patterning? I
guess if you're getting good results, that's all that really matters for
your application.
--
-Mike-
[email protected]
Frank Stutzman <[email protected]> wrote in
news:[email protected]:
> I did my air in black iron pipe, mostly because of the dangers of
> exploding PVC as already mentioned by other posters. In hindsight,
> I'm wondering if I might have done better with PVC.
You're better without the PVC. If for nothing else but it allowing you
to be lazy.
> All of my lines are in the walls of my shop. There is 1/2 inch
> plywood on one side of them and steel siding on the other. I'd do
> black iron pipe where it came through the wall, but other than that
> the PVC would be well protected.
How are you going to show that off to friends that drop by?
> Anybody wager a guess if an exploding 1 inch PVC pipe could go through
> 1/2 inch plywood? The pipes couldn't be hit by anything, but summer
> heat might soften the PVC to the point it would burst
When that happens and you want to use the air again, you're probably
going to be quite impatient.
> --
> Frank Stutzman
>
Hm... looks like the virtues of a Perl programmer apply to more than just
Perl. :-)
http://www.netropolis.org/hash/perl/virtue.html (An explanation)
Puckdropper
--
Wise is the man who attempts to answer his question before asking it.
To email me directly, send a message to puckdropper (at) fastmail.fm
Frank Stutzman <[email protected]> wrote in
news:[email protected]:
> Puckdropper <[email protected]> wrote:
>> Frank Stutzman <[email protected]> wrote in
>> news:[email protected]:
>>
>>> I did my air in black iron pipe, mostly because of the dangers of
>>> exploding PVC as already mentioned by other posters. In hindsight,
>>> I'm wondering if I might have done better with PVC.
>>
>> You're better without the PVC. If for nothing else but it allowing
>> you to be lazy.
>
> And you are implying that there is something wrong with being lazy?
>
> Besides allowing me to be lazy, the PVC would also allow me to be
> cheap. Cheap AND lazy. Be still my beating heart ;-)
>
>>> All of my lines are in the walls of my shop. There is 1/2 inch
>>> plywood on one side of them and steel siding on the other. I'd do
>>> black iron pipe where it came through the wall, but other than that
>>> the PVC would be well protected.
>>
>> How are you going to show that off to friends that drop by?
>
> As you implied, I'm lazy. When friends drop by the shop, we drink
> beer. Beer + whirling sharp things means missing fingers, which
> is a shop verboten ("ten in, ten out" is written on the door).
>
> Doubt if any of the beer swillers really give a damn what my plumbing
> is like. Pneumatic plumbing.
>
>>> Anybody wager a guess if an exploding 1 inch PVC pipe could go
>>> through 1/2 inch plywood? The pipes couldn't be hit by anything,
>>> but summer heat might soften the PVC to the point it would burst
>>
>> When that happens and you want to use the air again, you're probably
>> going to be quite impatient.
>
> True. But I spent better than a week cutting, threading and cursing
> that black pipe. I could have done the PVC thing in a few hours.
> Could have made a lot of sawdust in that week. If the heat caused a
> failure once in 10 years then maybe the trade off might be worth it.
>
>> Hm... looks like the virtues of a Perl programmer apply to more than
>> just Perl. :-)
>>
>> http://www.netropolis.org/hash/perl/virtue.html (An explanation)
>
> Again, you imply being lazy, impatient and full of hubris is a bad
> thing. Its worked for me for 45 years.
Do I? The intent was to point out that doing it well ("right" is
ambiguous here) the first time allows you to be lazy, impatient, and full
of hubris. Oh well, refer to the sky color on Usenet and someone will
think you meant grey instead of blue.
*snip*
Puckdropper
--
Wise is the man who attempts to answer his question before asking it.
To email me directly, send a message to puckdropper (at) fastmail.fm
<[email protected]> wrote in message
news:[email protected]...
>
> Anecdotal only. My boss at my old job had a neighbor
> who tired to inflate a space-saver spare tire to 32 psig
> or so instead of the rated maximum.
Moden day space saver tires are usually inflated in excess of 50lbs. I
suspect his spave saver tire was old and rottten.
On Tue, 5 Dec 2006 19:32:17 +0000 (UTC), Frank Stutzman
<[email protected]> wrote:
>True. But I spent better than a week cutting, threading and cursing that
>black pipe. I could have done the PVC thing in a few hours. Could have
>made a lot of sawdust in that week. If the heat caused a failure once in
>10 years then maybe the trade off might be worth it.
A week! How big is your shop anyway? I've plumbed an entire house with
galvanized in less than a week.
--
"We need to make a sacrifice to the gods, find me a young virgin... oh, and bring something to kill"
Tim Douglass
http://www.DouglassClan.com
Doug Miller wrote:
> In article <[email protected]>, "Robatoy"
> <[email protected]> wrote:
>
>> I want to see a report where it states that an air distribution line
>> exploded, pvc, copper. rubber... anything.
>
> If you hadn't found any such reports... it's because you didn't look. This is
> the very *first* hit turned up by a Google search on
> <"compressed air" pvc explosion>
>
> Here ya go...
> http://www.osha.gov/dts/hib/hib_data/hib19880520.html
>
> Here's another:
> http://www.woodworkersjournal.com/ezine/archive/159/readers.cfm
Of course he didn't look. He was hoping you wouldn't, either. Now he's
probably going to claim these don't count because the ambient temperature was
beyond parameters, or it was the wrong phase of the moon, or whatever.
You can rub this one all day but you can't put a polish on a turd. PVC line for
compressed gases is a dangerous game. Just because he's gotten away with it for
a lengthy period of time doesn't mean it's not ready to fail later today... or
tomorrow... with disasterous results.
--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com
"Frank Stutzman" <[email protected]> wrote in message
news:[email protected]...
> Max <[email protected]> wrote:
> > Is there any consensus on whether or not to use PVC or CPVC for air
lines?
>
> I did my air in black iron pipe, mostly because of the dangers of
> exploding PVC as already mentioned by other posters. In hindsight, I'm
> wondering if I might have done better with PVC.
>
> All of my lines are in the walls of my shop. There is 1/2 inch plywood on
> one side of them and steel siding on the other. I'd do black iron pipe
> where it came through the wall, but other than that the PVC would be
> well protected.
>
> Anybody wager a guess if an exploding 1 inch PVC pipe could go through 1/2
> inch plywood? The pipes couldn't be hit by anything, but summer heat
> might soften the PVC to the point it would burst
>
I doubt it would go through, but why would you want to do it anyway? Your
chances of a PVC failure or a glue joint failure are pretty high - very high
compared to black pipe or copper. Even if you don't get hurt by it, you
still have to deal with the repair to the lines.
--
-Mike-
[email protected]
"Brian Elfert" <[email protected]> wrote in message
news:[email protected]...
> "Mike Marlow" <[email protected]> writes:
>
>
> >> There is also DOT air hose used in trucks/buses with air brakes. You
can
> >> buy it at any heavy truck dealer and you can also get compression
> >> fittings. The 1/2" diameter should carry enough air for the average
shop.
> >>
>
> >Holy Cow Brian... $$$$$$$$
>
> I just did a quick search online and found 1/2" DOT air line for 71 cents
> per foot. This was at a street rod place, so a truck dealer should be
> less.
>
> 71 cents a foot is a lot less than copper. don't know what black pipe
> goes for these days.
>
> There is a 500 foot roll on ebay for 35 cents a foot plus shipping.
>
Yeahbut, how much for getting connectors crimped on? Maybe in bulk it
really won't be so bad, but my first reaction was to the thought of what a
simple short length of pre-made air line can cost. I still would not go
with 1/2" line - too much air restriction over length.
--
-Mike-
[email protected]
[email protected] wrote:
> IIRC, plastic soda-pop bottles are rated for about 150 psig.
> So you could take a small one, put some vinegar in it and
> then drop in some baking soda wrapped in wax paper,
> screw on the cap and put it somewhere safe to see how
> big a bang it makes.
When I was a kid, would use a glass Mason jar, put in a rock for
weight, some carbide and water, then screw on lid and toss in the creek.
The carbide and water combined to produce acetylene gas which would
expand and cause the glass jar to burst while under water.
Any fish would float to the surface for easy pickings.
Lew
"B A R R Y" <[email protected]> wrote in message
news:[email protected]...
> Mike Marlow wrote:
> >
> > Wasn't the original post referring to 1/2" air hose?
> >
>
> I didn't think so. My original mention of flexible hose simply stated
> "air hose".
Ok - assumption on my part.
> The stuff in the bike shop is a product that I think comes
> from the commercial beverage dispensing industry. FWIW, this is a big
> bike shop, with lots of repair / build stations in multiple rooms, not
> what you'd typically see. Their usual use of compressed air is blow
> guns, so the demand can be pretty good during peak tune / clean season.
>
Pretty low demand by air compressor/delivery system standards.
> I'm with you all the way if the line is driving die grinders, air
> routers, and sanders all day long. I'd probably just run a pipe to that
> work area. For the average one or two person shop we talk about here,
> even 1/2" hose should be fine.
Lots of guys want to do spray painting and that kind of delivery capacity,
especially with smaller compressors, will hurt their efforts. For a small
operation like most folks here have, and some simple blow gun, air nailer,
etc., low air volume operations, I agree it could be suitable. If they
envision larger air volume requirements though, I'd suggest some pipe - and
these days that pipe would be copper. Mine is a black pipe system, and if I
had it to do over again, I'd go copper.
--
-Mike-
[email protected]
"B A R R Y" <[email protected]> wrote in message
news:[email protected]...
> Mike Marlow wrote:
> >
> >
> > Depends on what you want to do with the air. If you're planning on
running
> > some demanding air tools or painting, then this won't work very well.
Too
> > much restriction which results in poor delivery and pressure loss.
>
> Depends on the size of the hose. <G>
Wasn't the original post referring to 1/2" air hose?
--
-Mike-
[email protected]
"J. Clarke" <[email protected]> wrote in message
news:[email protected]...
> On Wed, 06 Dec 2006 08:40:18 -0500, Mortimer Schnerd, RN wrote:
>
>
> Truck tire "explosions" are common--it's not the tire that explodes but an
> improperly assembled rim that separates, and if one of the pieces hits
> someone he generally gets hurt--truck wheels are rather large and the rims
> are rather heavy.
>>
If you are actually mounting a tire on a split rim you have the very real
possibility of the ring coming off and causing damage. Additionally it is
becoming less common to see split rim wheels and tires do explode when being
seated on regular one piece wheels.
Mike Marlow wrote:
>
> I doubt it would go through, but why would you want to do it anyway?
Me too, but as I think about this something else comes to mind...
If the PVC failed, and the wall was tightly constructed, the inside of
the wall would become quickly pressurized. If the airline was fed from
a larger capacity tank that didn't run out of air as the air expanded to
fill the wall, the would thing episode make for some interesting results.
The scary stuff would probably be contained, but I wouldn't want to be
next to it when it went, or with my hands near a spinning blade. At the
least, I'd have dirty underwear. <G>
One alternative not yet mentioned is plumbing with actual air hose.
My buddies large bicycle shop is done that way, as there were enough
funky curves to make it worthwhile. He's got 10-12 outlets tee'd off of
a basement compressor.
My own shop has a centrally located 50 foot hose reel hanging from the
ceiling, with vinyl coated bicycle hooks strategically located. I just
pull the hose to where I need it and put it in some hooks to keep it out
of the way.
FWIW, the hooks are also great for temporary power cables, hanging
bungee pickups for handheld tool dust hoses, etc...
"Dave Balderstone" wrote
Max wrote:
>
>> Is there any consensus on whether or not to use PVC or CPVC for air
>> lines?
>
> If you like the idea of PVC shards being driven about the shop by 150
> psi pressure, I say go fer it.
Sounds fascinating but I think I'll pass.
I considered black pipe but it's heavy, ugly, and a hassle to cut and thread
even though I have the required tools.
Over a hundred bucks for the copper choice but what the hell, it's only
money.
Max (bemoaning the price of copper)
In article <[email protected]>, "Max" <[email protected]> wrote:
>Is there any consensus on whether or not to use PVC or CPVC for air lines?
Yes, there is -- don't.
>My compressor is capable of 150psi.
>I already have copper for most of my distribution system but I need to add a
>branch and the copper prices are profanity inducing.
So use steel. Never, never, never, never use PVC/CPVC for compressed air. It's
been discussed here a number of times before. Do a Google Groups search on
this newsgroup, and I'm sure you'll find a few horror stories.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
In article <[email protected]>, "Robatoy" <[email protected]> wrote:
>I want to see a report where it states that an air distribution line
>exploded, pvc, copper. rubber... anything.
If you hadn't found any such reports... it's because you didn't look. This is
the very *first* hit turned up by a Google search on
<"compressed air" pvc explosion>
Here ya go...
http://www.osha.gov/dts/hib/hib_data/hib19880520.html
Here's another:
http://www.woodworkersjournal.com/ezine/archive/159/readers.cfm
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
Robatoy wrote:
> Find me one report/link to an accident that didn't involve air
> pressures greater than 150 psig or an explosive (oil) mixture.
>
> One!
The very first listing from googling "shop air explosion" revealed one occasion
where 140psi of air was accidentally put in a truck tire which then exploded,
killing the worker. No explosive mixture... just air pressure less than 150
psi.
http://www.state.nj.us/health/eoh/survweb/01nj108.pdf .
Compressed air is nothing to play with.
--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com
"Brian Elfert" <[email protected]> wrote in message
news:[email protected]...
> "[email protected]" <[email protected]> writes:
>
>>How about nylon tubing? This is similar to what I use:
>
>>http://www.wicksaircraft.com/catalog/product_cat.php/subid=1745/
>
>>425psi working pressure, 1700psi burst, it connects easily with brass
>>compression fittings and it's flexible making routing easy. All for
>>$0.91/ft.
>
> There is also DOT air hose used in trucks/buses with air brakes. You can
> buy it at any heavy truck dealer and you can also get compression
> fittings. The 1/2" diameter should carry enough air for the average shop.
>
> Brian Elfert
Good thought, Brian. Wish I had waited a couple days. Already about half
finished with the air line branch......in copper.
Max
Think again. Explosion due to rupture of a vessel containing a compressed
gas is extremely violent. High pressure gas cylinders are pressure tested
with a non compressible liquid for this reason.
"Robatoy" <[email protected]> wrote in message
news:[email protected]...
>
> Only if you fill the cavity with an explosive mixture.
> Air pressure alone will not have that catastrophic an effect.
> At worst, the 'shrapnel' will fall at your feet.
>
Robatoy wrote:
> Leon wrote:
>
>
>>Yes those were the original space savers with a canister of air for filling.
>
>
> The 2006 Porsche Carrera GT comes with a can of puncture fix. No spare.
> Reason being, that there is no room for a spare..even a small temporary
> one, but most of all there certainly isn't any room to put any of the
> wheel/tires that would come off the car... even when flat. HUGE rear
> wheels. (335/30 ZR20 got to get them 600 ponies to the street somehow,
> eh?)
>
> Don't need no steeenking spares....
>
If you can afford the car you don't need a spare. Two phone calls, one
to your limo drive to pick you up and one to "Estate Maintenance" to
came and get the car.
--
Jack Novak
Buffalo, NY - USA
[email protected]
I already bought the damn copper!!!
That stuff sure looks like the way to go though.
Max (wishing he wasn't so impulsive)
<[email protected]> wrote in message
news:[email protected]...
> How about nylon tubing? This is similar to what I use:
>
> http://www.wicksaircraft.com/catalog/product_cat.php/subid=1745/
>
> 425psi working pressure, 1700psi burst, it connects easily with brass
> compression fittings and it's flexible making routing easy. All for
> $0.91/ft.
>
> -Brian
>
> Max wrote:
>> Is there any consensus on whether or not to use PVC or CPVC for air
>> lines?
>> My compressor is capable of 150psi.
>> I already have copper for most of my distribution system but I need to
>> add a
>> branch and the copper prices are profanity inducing.
>>
>> Max
"Robatoy" <[email protected]> wrote in news:1165417304.856433.40150
@l12g2000cwl.googlegroups.com:
>
> Robatoy wrote:
> Had a crimp come off a cheap airline once.. chased one of the
>> guys around the paint-booth real good..
>
> which reminded me....
>
>
> Same guy took a full swing with a #1 wood at a golf-ball in his tiled
> bathroom.
> 33 cuts, 112 contusions and 44 lacerations.
> Good thing his roommate heard the commotion and opened the door to let
> the ball out.
>
>
Bright fellow, no?
Patriarch
In article <[email protected]>,
Max <[email protected]> wrote:
>Is there any consensus on whether or not to use PVC or CPVC for air lines?
>My compressor is capable of 150psi.
>I already have copper for most of my distribution system but I need to add a
>branch and the copper prices are profanity inducing.
>
>Max
>
>
Neither PVC nor CPVC is considered safe for compressed air service.
This is according to both OSHA and the pipe manufacturers. There are
some flexible plastic products that can be used for air lines, i don't
know how they price compared to copper.
--
For every complicated, difficult problem, there is a simple, easy
solution that does not work.
Larry Wasserman - Baltimore Maryland - [email protected]
On 4 Dec 2006 18:05:43 -0800, "Bill" <[email protected]> wrote:
>
>PVC that gets bumped becomes a schrapnel (sp?) bomb.
>
>Bill in WNC mountains
...uh, so would you like to provide some context with that?
[I've got quite a few feet of PVC pipe in my drip system that I've bumped a
few thousand times and thus far, no shrapnel]
+--------------------------------------------------------------------------------+
If you're gonna be dumb, you better be tough
+--------------------------------------------------------------------------------+
In article <[email protected]>, Frank Stutzman <[email protected]> wrote:
>True. But I spent better than a week cutting, threading and cursing that
>black pipe. I could have done the PVC thing in a few hours. Could have
>made a lot of sawdust in that week. If the heat caused a failure once in
>10 years then maybe the trade off might be worth it.
Probably not. DAGS. The failure of PVC pipe with compressed air is pretty
dramatic. The potential for injury and property damage is real.
--
Regards,
Doug Miller (alphageek at milmac dot com)
It's time to throw all their damned tea in the harbor again.
On Fri, 8 Dec 2006 00:31:28 +0000 (UTC), Frank Stutzman
<[email protected]> wrote:
>Tim Douglass <[email protected]> wrote:
>> On Tue, 5 Dec 2006 19:32:17 +0000 (UTC), Frank Stutzman
>> <[email protected]> wrote:
>>
>>>True. But I spent better than a week cutting, threading and cursing that
>>>black pipe. I could have done the PVC thing in a few hours. Could have
>>>made a lot of sawdust in that week. If the heat caused a failure once in
>>>10 years then maybe the trade off might be worth it.
>>
>> A week! How big is your shop anyway? I've plumbed an entire house with
>> galvanized in less than a week.
>
>1,400 sq ft.
Huh! That's bigger than my house.
>In my defense, I had never worked with black pipe before and I was probably
>not so effecient with the cutting and threading. Also didn't help that
>I changed by design once or twice while doing it.
We'll go with the changing design excuse. That one always seems to
work well for me. ;-)
--
"We need to make a sacrifice to the gods, find me a young virgin... oh, and bring something to kill"
Tim Douglass
http://www.DouglassClan.com
Mike Marlow wrote:
>
> Wasn't the original post referring to 1/2" air hose?
>
I didn't think so. My original mention of flexible hose simply stated
"air hose". The stuff in the bike shop is a product that I think comes
from the commercial beverage dispensing industry. FWIW, this is a big
bike shop, with lots of repair / build stations in multiple rooms, not
what you'd typically see. Their usual use of compressed air is blow
guns, so the demand can be pretty good during peak tune / clean season.
I'm with you all the way if the line is driving die grinders, air
routers, and sanders all day long. I'd probably just run a pipe to that
work area. For the average one or two person shop we talk about here,
even 1/2" hose should be fine.
"B A R R Y" <[email protected]> wrote in message
news:[email protected]...
>
> The main delivery tubing is some sort of 1/2" to 5/8" ID plastic hose,
> tee'd off with barbed and clamped fittings. The main line is 100 to 125
> feet long, with 8 or 9 20-30' 3/8" air hose drops terminated with Milton
> quick connects. The whole rig is run by an Ingersoll Rand 80 gallon
> 220v compressor. I don't know the HP rating of the compressor, but the
> airline is typically charged to 125 PSI.
>
> I connected a standard, 50' x 3/8" hose to the final connector so I
> could spray in the parking lot behind the building. Several large
> items were sprayed this way. Spray results were as good as I get with
> my Fuji 4 stage HVLP rig. However, nobody else was using air. I don't
> believe this setup would have worked if others were using air, nor would
> I install it in a professional finishing shop or auto paint shop.
Pretty interesting Barry. You've got the pressure and likely, the delivery
capacity in the compressor to somewhat compensate for the friction
loss/restriction in the hose so you're probably ok - or so I would guess. I
really don't stay up late at night calculating these things...
--
-Mike-
[email protected]
"DJ Delorie" <[email protected]> wrote in message
news:[email protected]...
>
> "J. Clarke" <[email protected]> writes:
> > How much is it going to cost you to tear the wall out and replace a
busted
> > pipe?
>
> Assuming the explosion doesn't tear the wall out for you ;-)
>
> Think "pipe bomb".
I think a pipe bomb has quite a bit more than 120 or so psi behind it.
--
-Mike-
[email protected]
"B A R R Y" <[email protected]> wrote in message
news:[email protected]...
> One alternative not yet mentioned is plumbing with actual air hose.
>
> My buddies large bicycle shop is done that way, as there were enough
> funky curves to make it worthwhile. He's got 10-12 outlets tee'd off of
> a basement compressor.
>
Depends on what you want to do with the air. If you're planning on running
some demanding air tools or painting, then this won't work very well. Too
much restriction which results in poor delivery and pressure loss. For a
bike shop that might be ok, but for some of the common tools found in a
shop/garage it wouldn't be a very good solution.
--
-Mike-
[email protected]
"Brian Elfert" <[email protected]> wrote in message
news:[email protected]...
> "[email protected]" <[email protected]> writes:
>
> >How about nylon tubing? This is similar to what I use:
>
> >http://www.wicksaircraft.com/catalog/product_cat.php/subid=1745/
>
> >425psi working pressure, 1700psi burst, it connects easily with brass
> >compression fittings and it's flexible making routing easy. All for
> >$0.91/ft.
>
> There is also DOT air hose used in trucks/buses with air brakes. You can
> buy it at any heavy truck dealer and you can also get compression
> fittings. The 1/2" diameter should carry enough air for the average shop.
>
Holy Cow Brian... $$$$$$$$
--
-Mike-
[email protected]
Max <[email protected]> wrote:
> Is there any consensus on whether or not to use PVC or CPVC for air lines?
I did my air in black iron pipe, mostly because of the dangers of
exploding PVC as already mentioned by other posters. In hindsight, I'm
wondering if I might have done better with PVC.
All of my lines are in the walls of my shop. There is 1/2 inch plywood on
one side of them and steel siding on the other. I'd do black iron pipe
where it came through the wall, but other than that the PVC would be
well protected.
Anybody wager a guess if an exploding 1 inch PVC pipe could go through 1/2
inch plywood? The pipes couldn't be hit by anything, but summer heat
might soften the PVC to the point it would burst
--
Frank Stutzman
On Tue, 05 Dec 2006 18:16:36 +0000, Frank Stutzman wrote:
> Max <[email protected]> wrote:
>> Is there any consensus on whether or not to use PVC or CPVC for air lines?
>
> I did my air in black iron pipe, mostly because of the dangers of
> exploding PVC as already mentioned by other posters. In hindsight, I'm
> wondering if I might have done better with PVC.
>
> All of my lines are in the walls of my shop. There is 1/2 inch plywood on
> one side of them and steel siding on the other. I'd do black iron pipe
> where it came through the wall, but other than that the PVC would be
> well protected.
>
> Anybody wager a guess if an exploding 1 inch PVC pipe could go through 1/2
> inch plywood? The pipes couldn't be hit by anything, but summer heat
> might soften the PVC to the point it would burst
How much is it going to cost you to tear the wall out and replace a busted
pipe?
> --
> Frank Stutzman
Puckdropper <[email protected]> wrote:
> Frank Stutzman <[email protected]> wrote in
> news:[email protected]:
>
>> I did my air in black iron pipe, mostly because of the dangers of
>> exploding PVC as already mentioned by other posters. In hindsight,
>> I'm wondering if I might have done better with PVC.
>
> You're better without the PVC. If for nothing else but it allowing you
> to be lazy.
And you are implying that there is something wrong with being lazy?
Besides allowing me to be lazy, the PVC would also allow me to be
cheap. Cheap AND lazy. Be still my beating heart ;-)
>> All of my lines are in the walls of my shop. There is 1/2 inch
>> plywood on one side of them and steel siding on the other. I'd do
>> black iron pipe where it came through the wall, but other than that
>> the PVC would be well protected.
>
> How are you going to show that off to friends that drop by?
As you implied, I'm lazy. When friends drop by the shop, we drink
beer. Beer + whirling sharp things means missing fingers, which
is a shop verboten ("ten in, ten out" is written on the door).
Doubt if any of the beer swillers really give a damn what my plumbing is
like. Pneumatic plumbing.
>> Anybody wager a guess if an exploding 1 inch PVC pipe could go through
>> 1/2 inch plywood? The pipes couldn't be hit by anything, but summer
>> heat might soften the PVC to the point it would burst
>
> When that happens and you want to use the air again, you're probably
> going to be quite impatient.
True. But I spent better than a week cutting, threading and cursing that
black pipe. I could have done the PVC thing in a few hours. Could have
made a lot of sawdust in that week. If the heat caused a failure once in
10 years then maybe the trade off might be worth it.
> Hm... looks like the virtues of a Perl programmer apply to more than just
> Perl. :-)
>
> http://www.netropolis.org/hash/perl/virtue.html (An explanation)
Again, you imply being lazy, impatient and full of hubris is a bad thing.
Its worked for me for 45 years.
(what is really scary is I knew exactly what you were talking about without
even looking at that URL).
--
Frank Stutzman
On Tue, 05 Dec 2006 14:33:14 -0500, DJ Delorie wrote:
> "Mike Marlow" <[email protected]> writes:
>> I think a pipe bomb has quite a bit more than 120 or so psi behind it.
>
> Yeah, but the failure modes are the same. Copper, however, doesn't
> fracture at shop pressures - it peels back, which is a "safe" way to
> fail in a shop, since there's no flying shrapnel.
On the other hand, the ballistic coefficient of PVC shards is going
to be pretty low.
This would be a good one for "Mythbusters".
On Wed, 06 Dec 2006 08:40:18 -0500, Mortimer Schnerd, RN wrote:
> Robatoy wrote:
>> Find me one report/link to an accident that didn't involve air
>> pressures greater than 150 psig or an explosive (oil) mixture.
>>
>> One!
>
>
> The very first listing from googling "shop air explosion" revealed one occasion
> where 140psi of air was accidentally put in a truck tire which then exploded,
> killing the worker. No explosive mixture... just air pressure less than 150
> psi.
>
> http://www.state.nj.us/health/eoh/survweb/01nj108.pdf .
>
> Compressed air is nothing to play with.
Truck tire "explosions" are common--it's not the tire that explodes but an
improperly assembled rim that separates, and if one of the pieces hits
someone he generally gets hurt--truck wheels are rather large and the rims
are rather heavy.
>
>
>
--
--John
to email, dial "usenet" and validate
(was jclarke at eye bee em dot net)
Tim Douglass <[email protected]> wrote:
> On Tue, 5 Dec 2006 19:32:17 +0000 (UTC), Frank Stutzman
> <[email protected]> wrote:
>
>>True. But I spent better than a week cutting, threading and cursing that
>>black pipe. I could have done the PVC thing in a few hours. Could have
>>made a lot of sawdust in that week. If the heat caused a failure once in
>>10 years then maybe the trade off might be worth it.
>
> A week! How big is your shop anyway? I've plumbed an entire house with
> galvanized in less than a week.
1,400 sq ft.
In my defense, I had never worked with black pipe before and I was probably
not so effecient with the cutting and threading. Also didn't help that
I changed by design once or twice while doing it.
--
Frank Stutzman
Robatoy wrote:
>> Robatoy wrote:
>>> Find me one report/link to an accident that didn't involve air
>>> pressures greater than 150 psig or an explosive (oil) mixture.
>>
>>> One!The very first listing from googling "shop air explosion" revealed one
>>> occasion
>> where 140psi of air was accidentally put in a truck tire which then exploded,
>> killing the worker. No explosive mixture... just air pressure less than 150
>> psi.
>
> That's not a shop-air explosion. That is an idiot overinflating a tire.
> Using that barometer (I made a funny), I am sure there are many
> air-related accidents.
Look at the first line you wrote above: I met every criteria you asked for.
Now you're adding conditions?
--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com
"Lew Hodgett" <[email protected]> wrote in message
news:[email protected]...
> Robatoy wrote:
>
> > Only if you fill the cavity with an explosive mixture.
> > Air pressure alone will not have that catastrophic an effect.
> > At worst, the 'shrapnel' will fall at your feet.
>
> BULL SHIT! !
>
> Lew
Oh yeah!! That stuff can serve as shrapnel too. Ever heard the expression,
"When the shit hit the fan".
Max
"Lew Hodgett" <[email protected]> wrote in message
news:[email protected]...
> Robatoy wrote:
>
> > Find me one report/link to an accident that didn't involve air
> > pressures greater than 150 psig or an explosive (oil) mixture.
>
> Why would you expect to find reports of something that isn't done?
>
> Lew
I would like to see a *reliable* report of schedule 40 PVC exploding at an
air pressure of 150 psi. Note the "reliable".
Max (who is satisfied that it just might be possible)
<[email protected]> wrote in message
news:[email protected]...
>
> Leon wrote:
>> <[email protected]> wrote in message
>> news:[email protected]...
>> >
>> > Anecdotal only. My boss at my old job had a neighbor
>> > who tired to inflate a space-saver spare tire to 32 psig
>> > or so instead of the rated maximum.
>>
>> Moden day space saver tires are usually inflated in excess of 50lbs. I
>> suspect his spave saver tire was old and rottten.
>
> Old yes. Not rotten. The original ones were only to be inflated
> to 12 psig or something like that. Accidents of the sort described
> are why those are no longer available.
>
> Memory dims but I think they were collapsible with the tire folded
> into the rim.
Yes those were the original space savers with a canister of air for filling.
The consensus in many previous threads is to *never* use PVC for air.
jc
"Max" <[email protected]> wrote in message
news:[email protected]...
> Is there any consensus on whether or not to use PVC or CPVC for air lines?
> My compressor is capable of 150ps.
> I already have copper for most of my distribution system but I need to add
> a branch and the copper prices are profanity inducing.
>
> Max
>
>
"Mark & Juanita" <[email protected]> wrote in message
news:[email protected]...
> On 4 Dec 2006 18:05:43 -0800, "Bill" <[email protected]> wrote:
>
>>
>>PVC that gets bumped becomes a schrapnel (sp?) bomb.
>>
>>Bill in WNC mountains
>
> ...uh, so would you like to provide some context with that?
>
> [I've got quite a few feet of PVC pipe in my drip system that I've bumped
> a
> few thousand times and thus far, no shrapnel]
You might want to keep an eye on it. I have seen it become very brittle and
shatter with no air pressure when I was attempting to cut it.
Frank Stutzman wrote:
> Anybody wager a guess if an exploding 1 inch PVC pipe could go through 1/2
> inch plywood? The pipes couldn't be hit by anything, but summer heat
> might soften the PVC to the point it would burst
Summer heat will do a lot more than soften PVC; it will raise the pressure of
the compressed gas.
--
Mortimer Schnerd, RN
mschnerdatcarolina.rr.com
Mike Marlow wrote:
> "B A R R Y" <[email protected]> wrote in message
>> Mike, I have spray painted with that setup. <G>
>
> How much? I have to admit that I tend to think in bigger terms than
> woodworking, owing to the type of painting I do, so that's my shortcoming in
> a discussion like this. I suppose for typical small scale painting it could
> be ok.
>
> How much small diameter hose do you have in your delivery system? Do you so
> small scale spraying? Are you getting good atomization and patterning? I
> guess if you're getting good results, that's all that really matters for
> your application.
>
The main delivery tubing is some sort of 1/2" to 5/8" ID plastic hose,
tee'd off with barbed and clamped fittings. The main line is 100 to 125
feet long, with 8 or 9 20-30' 3/8" air hose drops terminated with Milton
quick connects. The whole rig is run by an Ingersoll Rand 80 gallon
220v compressor. I don't know the HP rating of the compressor, but the
airline is typically charged to 125 PSI.
I connected a standard, 50' x 3/8" hose to the final connector so I
could spray in the parking lot behind the building. Several large
items were sprayed this way. Spray results were as good as I get with
my Fuji 4 stage HVLP rig. However, nobody else was using air. I don't
believe this setup would have worked if others were using air, nor would
I install it in a professional finishing shop or auto paint shop.
<[email protected]> wrote in message
news:[email protected]...
> How about nylon tubing? This is similar to what I use:
>
> http://www.wicksaircraft.com/catalog/product_cat.php/subid=1745/
>
> 425psi working pressure, 1700psi burst, it connects easily with brass
> compression fittings and it's flexible making routing easy. All for
> $0.91/ft.
>
> -Brian
Not bad for a snub or whip hose, but at only .279" ID, not a lot of air is
going to get thru it to the tool where it's needed.
Mike
"Mike Marlow" <[email protected]> writes:
> I think a pipe bomb has quite a bit more than 120 or so psi behind it.
Yeah, but the failure modes are the same. Copper, however, doesn't
fracture at shop pressures - it peels back, which is a "safe" way to
fail in a shop, since there's no flying shrapnel.
"J. Clarke" <[email protected]> writes:
> How much is it going to cost you to tear the wall out and replace a busted
> pipe?
Assuming the explosion doesn't tear the wall out for you ;-)
Think "pipe bomb".