We have a Cnc plasma at work and we have the compressor connected via approx 20m of John guest plastic pipe 28mm dia, we have approx 2 bar pressure drop over this distance, if I double up on the 28mm pipe and complete a ring circuit back to the compressor will this reduce the pressure drop, we need to maintain about 8 bar at machine and although compressor maintains 9 bar we are seeing about 7 at regulator by machine, I am hoping that by effectively doubling pipe area by a ring being 2 pipes from compressor it would reduce the drop, does this sound correct.
- Thread starter Daz1968
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brightspark
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are u sure your loosing the the pressure in the pipe or through the regulator at the end.i ran one either end of my blasting pot and noticed the loss having both in line . took one out and it was noticably improved
captain-destructo
all the gear no idea
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hi there
is the flow of air restricted where it go's from the compressor to the pipework?
this may sound stupid but how is it connected to the reciever? 28mm to ???BSP
is the flow of air restricted where it go's from the compressor to the pipework?
this may sound stupid but how is it connected to the reciever? 28mm to ???BSP
The plasma uses very little, we only have a 3hp compressor and it keeps up with it with a reasonable duty cycle, I have a 1/2 bsp tap on receiver that has a step up adaptor to 3/4 bsp for the 28mm pipework then 28mm to within 3 foot of regulator where it drops to 15mm to the 1/2 bsp regulator, its just on compressor it shows 11bar when it cuts out but we only have 9 bar on regulator, we do our cut stream on plasma with oxygen for steel and nitrogen for stainless so not really sure what the air shield does tbh, it's a 150ltr receiver. We also have very few bends in pipe work to minimise pressure drop, never had an issue when compressor was close to machine just moved it further away because of noise and to help get the air dry which is why I fitted the regulator.
normspanners
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You should never get that amount of pressure drop on 28mm pipe it actually should work as a reservoir, I would do away with the first reg but dont forget pressure gauges are not all equal it could be that the one gauge is showing low.
To stop water your main should run with a slight downward fall to the end and carry on past the last QR outlet, that outlet should be a tee but facing so that the outlet is upwards, then turn pipework down through 180deg to your QR coupling, that is done so that the water will condense in the main pipe run along the bottom to the end where it should turn 90 deg down to a tap to drain water out, and then no water gets to the QR.
To stop water your main should run with a slight downward fall to the end and carry on past the last QR outlet, that outlet should be a tee but facing so that the outlet is upwards, then turn pipework down through 180deg to your QR coupling, that is done so that the water will condense in the main pipe run along the bottom to the end where it should turn 90 deg down to a tap to drain water out, and then no water gets to the QR.
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I might leave the regulator for a blow gun and take another drop leg just before the existing one down to a coupling and try the plasma without the regulator, there is no regulator at the compressor the pipework comes straight out receiver so agree the pipework should just add to the receiver capacity, if that doesn't work will try completing a ring with the 28mm pipework. It's annoying really as I also thought 28mm pipe for the amount of air it uses should be plenty, I only have 22mm at home and get no pressure drop although I have a different regulator, maybe pcl are not as good as the smc one that I have.
normspanners
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try to make sure your dropleg is taken from the top of the main.
normspanners
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I think you may have a bad connection to the compressor tank, unscrew the JG pipe and check the tap if there is one (there should be H&S) if the connection is black iron not galv it will be rusty but it may have rusted and sludged up to the point of partial blockage, I have seen galv ones block for similiar reasons.
Forming a ring will not improve your situation unless connected to another port in the cyl
the jet in your plasma will only be very small less than 1mm so even a10mm pipe over 20m should flow enough air with no drop.
At the moment I am using big high CFM 1/2" air tools about 40m away at 10bar on 10mm rubber hose with a few QRs in that, the only trouble I have had is when it was freezing then I was suffering ice blockage.
Forming a ring will not improve your situation unless connected to another port in the cyl
the jet in your plasma will only be very small less than 1mm so even a10mm pipe over 20m should flow enough air with no drop.
At the moment I am using big high CFM 1/2" air tools about 40m away at 10bar on 10mm rubber hose with a few QRs in that, the only trouble I have had is when it was freezing then I was suffering ice blockage.
I've had a regulator start freezing on me midway through spraying - blumin maddening! On that particular job I set up a fan heater pointing at the airtank and one at the regulator...
Julian.
