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Speedy
Canada
4194 Posts |
 Posted - 02/26/2010 : 21:40:18
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http://www.youtube.com/watch?v=EU_u5lXcnUI
I do not condone this method. A pressure washer should have been used, not compressed air. This proves the violence of 120 PSI compressed air in the wrong hands. Even 500 PSI of water would not be this explosive. |
If you can't fix it with a hammer....you've got an electrical problem. |
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ericicf
Canada
1164 Posts |
Posted - 02/27/2010 : 19:48:23
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What is the correct pressure washer hook-up?
How do you relieve pressure on the feed side? |
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Speedy
Canada
4194 Posts |
Posted - 02/27/2010 : 20:25:09
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You must temper this procedure with the knowledge of how sound your pipes are.
Quick couplers are available to attach different spray tips to the wand of a pressure washer (Princess Auto, Harbor Freight or Northern Tool)
Build a blow-out cap to use with the p/w. A pressure gauge would be a good idea, if it doesn't move with 500 psi, it's a total loss. In the above case, it is frozen mud, not hot mud that flashed. Once it starts thawing, there is water and paste available to lube. Heating the pipe from the outside would also expand it's circumference, loosening the slug of mud inside. |
If you can't fix it with a hammer....you've got an electrical problem. |
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06savana
220 Posts |
Posted - 02/27/2010 : 21:04:39
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Well I do not understand why this is not the way to clean out frozen pipe. I have done it this way before on a boom. The rule is do not aim it at anything you do not want to kill, just like a gun.
You could use a pressure washer but I would much rather use air at 120psi than a pressure washer at 500psi. I do not think all blow out caps are good for anything over 150psi.
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Speedy
Canada
4194 Posts |
Posted - 02/27/2010 : 21:25:34
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I do not like air. The reason being the stored energy in the compressed air.
With water, you are forcing the slug out with volume, not pressure. Sure, it takes pressure to get it to move (overcome friction), but as soon as it does, the pressure instantaneously drops.
As far as a rating on the blow-out cap, I'm not a fan of a flat plate welded on the end of a pipe, I'd rather see a manufactured weldable steel reducer with properly sized fittings. Clamps seem to handle 1000psi+ pumping pressure, but I'd be concerned about the potential for disaster with a pressure washer capable of 3,000psi or more. |
If you can't fix it with a hammer....you've got an electrical problem. |
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Godfather
USA
1909 Posts |
Posted - 02/28/2010 : 04:35:45
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If you have a pressure washer, add lengths of steel tubing, threaded between the trigger nozzle ass'y and the nozzle tip. Call the assembly a LANCE
Speedy, remember that you rigged a pipe rinse rack on the front of your old Mack cab.
Secure a plugged pipe on a slope, one end higher than the other. Slope could be the way you park the truck, or on a concrete driveway.
My preference is to work standing up, therefore a fork lift is my adjustable height slope
Run the Lance into the low end of the pipe; let the nozzle tip high pressure water do the demolition job. The cuttings rinse down the invert, onto the ground. Don't use the 50 dollar nozzle tip as a chipping tool.
Too simple? No brainer!
Go there, do that and more: bore a tunnel under a concrete sidewalk with a pressure washer.
For liability reasons, experienced mfg'rs and re-sellers won't assemble blow-out cap ass'ys.
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b.alto
USA
1001 Posts |
Posted - 02/28/2010 : 07:22:22
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| 3000 psi per lineal inch of pipe? that adds up quick. Per square inch x the circumference or say 12 inches around = 36000 pounds of pressure per lineal foot. Wear you safety glasses! Or maybe your bomb suit. |
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b.alto
USA
1001 Posts |
Posted - 02/28/2010 : 07:23:58
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| I meant 36000 per lineal inch. |
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Godfather
USA
1909 Posts |
Posted - 02/28/2010 : 09:03:18
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If you're disputing my write, please recognze that the pipe is OPEN ENDED!
THERE AIN'T NO PRESSURE IN THE PIPE except the fan spray at the tip of the lance. The fan spray cuts away the face of the "tunnel", reduces the tunnel face to coarse and fines which dribble out at your feet.
Potato Guns are more fun! |
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Speedy
Canada
4194 Posts |
Posted - 02/28/2010 : 09:27:28
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| Frozen mud is different than set mud. It would be easy to blast out with the p/w nozzle, especially the 'turbo' style. It would be messy though. To push it out with pressurized air is quicker. Done properly, it is safe. Using air is spectacular and 'fun' but infinitely more dangerous. |
If you can't fix it with a hammer....you've got an electrical problem. |
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06savana
220 Posts |
Posted - 02/28/2010 : 10:12:50
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I use to figure some of the total pressures and you can get some awesome pressures in a 5 inch pipe. Even a pumping pressure of 1000psi you will get 3600lbs of actual push.
I agree just using a pressure washer is what I would do if I was back at the shop and had only 3meter or less pieces of pipe. When I did it the pipe was still on the boom and having a 4meter long lance would have been a problem. I also had to have the truck inside to thaw out the concrete so it would have made a hell of a mess.
Did any of you see the thread, I think it was on the farsite about using a pressure washer to push set up concrete out of pipe. They clammed it worked almost every time and it did not make any difference how old the mud was. The main problem was it may push the lining right out of the pipe. Would be interesting to try if a guy has some not so old pipe with set up concrete in it. |
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b.alto
USA
1001 Posts |
Posted - 02/28/2010 : 10:52:43
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| GF I was not disputing what you stated. I was discussing the technique of pressuring out the whole clump of mud in one push. I see now what you are talking about using the pressure washer and a lance to clean out the pipe, that makes good sense. 3000- 2000 pressure water would chew up some mud, and back wash out with an angle. And be much safer! Probably even day old green mud. |
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curlyred
86 Posts |
Posted - 02/28/2010 : 18:09:39
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| Better yet....A stick of dynamite shoved in the pipe close the end and a bunker would have been safer. |
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Speedy
Canada
4194 Posts |
Posted - 02/28/2010 : 18:38:48
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| Curlyred, we're going to have to send to back to safety class. |
If you can't fix it with a hammer....you've got an electrical problem. |
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Digger
Australia
168 Posts |
Posted - 02/28/2010 : 20:48:21
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I had a 28 metre 4 stage boom working on a site on a 35 degree C summer day. They served up a hot load and he looked like doing his complete boom pipes. Called us for a larger blowout cap to reverse blowout with air. I put together a water blaster cap. The mud was 2.5 hours old by the time we got to the boom. Set up his on board hyd water blaster to the cap, inserted a sponge, started the blaster. It went to 1,500 psi before the mud started to move, but it blew the line clear thru all the 90's and straight pipes. You could sit on the slugs.
It saved the system, so now a water blaster blow out cap is a standard accessory in most pumps now. Any one with a hydraulic water blaster fitted to their pump should have a cap for water. |
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curlyred
86 Posts |
Posted - 03/01/2010 : 20:15:45
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| A set up with controlled pressure, pressure release and maybe a gauge would be nice to have. I have thought about the pressure washer idea before, never done it. |
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Topic |
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Blowing out frozen system
