Replies

1. 
   sschefer | Jul 17, 2002 07:09pm | #1

   This question was asked a while back when it was reported that a person narrowly escaped death from an exploding tank. The general concensous was that it was a good idea to drain it down to get rid of the water. I drain mine about once a week under heavy use and once a month under light use.

   Here's a link to an article that discusses a problem that Ingersol-Rand discovered. You'll need adobe acrobat reader to open it. Go to http://www.adobe.com for the reader if you don't already have it. The recall article is on page four.

   http://www.cslb.ca.gov/forms/clcspr2002.pdf

   Steve - in Northern California

   
   

   ---

   Edited 7/17/2002 12:13:37 PM ET by Steve Schefer

1. 
   DelDollens | Jul 17, 2002 07:22pm | #2

   I have a good size compressor and live in missouri where the air is fairly humid.  Combine those two and you have a lot of water in your tank.  I finally put a timer relay and hydraulic solenoid valve on the unit so that it exhausts the water out of the drain valve for a brief period after each cycle.

   Other than the build-up of water in your tank, I would think leaving the compressed air in you tank is safe.

   -Del

2. 
   forestgirl | Jul 17, 2002 07:35pm | #3

   Scoot, I'm surprised the answer to your question isn't in your owner's manual.  My PorterCable manual is very specific about draining the tank, and I do it every time.  Lots of workers out there are now laughing out loud, 'cause they never drain theirs, but I want mine to last as long as possible, and don't want it rusting through and exploding on me some day, much as I'd like a new garage.  (pardon the hyperbole)

   I do hope you read the manual, since your compressor may well have a break-in procedure that's explained in there also.

   Have fun with it!  They're handy little outfits.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

3. 
   JET | Jul 17, 2002 08:11pm | #4

   Also see the responses in the same post you left in homebuilding

4. 
   TKanzler | Jul 17, 2002 08:33pm | #5

   Drain the water, leave the air.  Residual air pressure won't hurt anything (steel doesn't get tired holding a load; it gets tired from changing loads, which is called fatigue).  For stationary compressors, you can use an automatic condensate drain or a truck air horn valve with sash chain lanyard for manual draining without bending down.  But in your case, if you're concerned about a child messing with it, by all means vent it down.  There's quite a bit of stored energy in there, depending on receiver size and pressure, and it does need to be treated with a bit of respect.

    

   Be seeing you...

1. 
   sbrunhgtv | Jul 17, 2002 09:24pm | #6

   Thanks for your reply.  I guess my biggest concern is not with children messing with the compresser, but with me transporting it in my SUV.  I don't really have a permanent "shop" that I use it in.  I'm always taking it on the road to different job sites.

   Thanks again for your tips.

   Scoot

1. 
   sschefer | Jul 17, 2002 09:31pm | #7

   Oh... that's says a lot more about the issue. Drain it completely of air before transporting it. All of the contractors that I have been involved with do this. If you have an accident and the tank is impacted it could eaisly explode and kill you and your occupants. I have the same compressor that you do and I never, repeat, never transport it while its pressurized. Steve - in Northern California

2. 
   Elcoholic | Jul 17, 2002 10:47pm | #8

   Big time no no in the SUV!  A friend of mine who considers himself a serious off-roader followed some pretty bad advice about using the inside spare tire as an air reservoir.  The theory at work here was that a tire could be over-inflated since it wasn't bearing the weight of the vehicle.  One day shortly after picking up a client from LAX and delivering him to his hotel the tire let go.  It blew out the widows after bulging the roof and body panels BEYOND REPAIR.  It totaled a late model Grand Cherokee Ltd. and left said friend with moderate permanent hearing damage.  Imagine the same event with a some chisels and a box or two of drywall screws nicely nestled around your compressor when you get rear ended.John O'Connell - JKO Handcrafted Woodworking

   Life is tough.  It's tougher if you're stupid - John Wayne

1. 
   TKanzler | Jul 17, 2002 11:14pm | #9

   I didn't realize you were transporting it in your vehicle.  I agree with the two posts above completely.  Vent it down.  As I said before, there's potentially a lot of stored energy in that receiver, and you don't need that danger in addition to the dangers of driving. 

   Be seeing you...

1. 
   dhpascoe | Jul 18, 2002 04:37am | #10

   At the usual 125-150psi range of most compressors, I hardly think an air tank is explosive. If it ruptured it sure would scare the hell out of you, and maybe propell itself a little bit, but it's not going to explode and make shrapnel. The only way a tank could possibly explode would be if the  compressor limit switch failed but I doubt that most pumps could even reach those kind of pressures. They have soft copper pipes from compressor to tank that will blow out long before the tank does.

   Dave

2. 
   forestgirl | Jul 18, 2002 05:09am | #11

   Here's a quote from the letter in Issue 156, Fine WWing (page 10):

   A number of years ago, I had the experience of having an air-compressor tank explode inside my two-car garage workshop.  The explosion blew the double garage doors into the driveway and sprayed shattered glass into the street.  The drywall inside the shop was collapsed between the studs, and the stucco outer wall had large cracks and a prominent bulge.  If I had been in the shop when it happened, I would surely have been killed or seriously injured.

   ...the [fire department] told me that the tank had corroded from the inside, thus becoming weak along a welded seam.

   The writer goes on to say that it was recommended his next compressor come with an ASME certified tank, evidently a requirement for commercial shops. 

   Granted, the chances of this happening are not great, but the consequences are pretty serious.  It takes me all of 30 seconds to drain my compressor, no biggie.forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

3. 
   gerry001 | Jul 18, 2002 02:53pm | #12

   I remember that FineWW letter, also. It did strike me as a little odd. It's unlikely the tank was overpressured, since there is an overpressure valve that would have opened if the limit switch failed. Then I recalled all the stories about static explosion in a small shop dust collection system, none of which was ever confirmed. Now, could this happen? Sure; anything could happen. But, what would it take? Remember, you haven't seen many of these stories around.

   Well, a small hole rusted out anywhere wouldn't do it. Ever miss while pushing an air coupling on a nail gun? Are you still standing when the hiss dies out? No, as was mentioned by the fire department, you need to have a complete failure in a major seam. Do that and you have an air-propelled rocket and, with a fair sized compressor, that could certainly pack a wallop. Also, apparently it wasn't ASME certified, so they may have cut some corners in the construction.

   Regarding fatigue, I'd offer that constant draining and filling is far worse than just leaving it filled. Still, for these pressures and typical home usage, I doubt it makes any practical difference. (Any ME's out there differ?)

   Still, there's some amount of danger, and it's always worthwhile to maintain your tools. I've got a 26 gal unit, and I tend to partially open the drain for a few seconds after a day's use, to spit out any collected water. As long as the unit is level, I don't see any reason to fully drain it. I'll note that larger units will often have a permanent water collector installed, that holds the water and allows you to see when it needs to be emptied.

   Gerry

4. 
   Jimma | Jul 18, 2002 05:42pm | #13

   It's a bit off-topic, maybe, but in the interest of helping someone here's how I deal with the "problem" of pooled moisture in my 60-gallon stationary shop compressor. It was suggested by a technician at Campbell-Hausfeld. Replace the drain #### at the bottom of the tank with a short 1/2 inch pipe (I use galvanized) which is then connected to a horizontal piece of pipe long enough to run outboard of the tank; this is then connected to a vertical piece 7 or 8 inches long which brings the pipe to a level above the bottom of the tank. A short piece of horizontal pipe is then fitted with a brass valve and an elbow to allow moisture to be exhausted into a bucket. In other words, it's a kind of U-shaped assembly with a valve that allows the moisture to collect in the pipe (instead of the tank) and be blown out at the end of the day -- or whenever. Ideally, instead of exhausting the moisture into a bucket, it could be exhausted to the outside, but my installation doesn't lend itself to that very well. You don't have to get on the floor to twist the factory-supplied drain #### and you get the moisture where you want it.

5. 
   Jimma | Jul 18, 2002 05:49pm | #14

   Can you believe what this lilly pure website does? In my post it has substituted #### for the four-letter word that normally follows drain- when referring to that little piece of plumbing that allows the thing to be opened or closed. Worse than Victorian, Tim. You guys should be ashamed of yourselves!

6. 
   forestgirl | Jul 18, 2002 06:31pm | #15

   Yep, the censors do it again!  Little word-puzzle for us.  I'm going to try making it all one word, and see if that works:  The #### is G-rated.

   Oh well, didn't work.  They're clever, those protectors of ours.

   forestgirl -- you can take the girl out of the forest, but you can't take the forest out of the girl   ;-)

   Edited 7/18/2002 11:32:33 AM ET by forest_girl

7. 
   Jimma | Jul 19, 2002 03:26am | #16

   Try ####.

8. 
   Elcoholic | Jul 26, 2002 10:44pm | #17

   Wasn't John #### allowed to sign the Declaration of Independence?  John Han pound pound pound pound just doesn't have the same ring to it.

   From now on let that draining device be known as the drainpud.

   Let's try a couple others - motor terminal boxes are known as peckerheads.  Insulators on guy wires are known as johnny balls.

   Sorry, I just couldn't resist.

   John O'Connell - JKO Handcrafted Woodworking

   Life is tough.  It's tougher if you're stupid - John Wayne

   Edited 7/26/2002 3:49:14 PM ET by ELCOHOLIC

9. 
   Jimma | Jul 26, 2002 11:28pm | #18

   Yuk,yuk! Maybe #####willow is on the list, too.

10. 
    BarryO | Jul 28, 2002 08:45am | #19

    Are you trying to say d r a i n c o c k ? 

    Yea, this sure is infantile.  Don't you appreciate being treated like you're in kndergarten?