How to clean a conduit?

[PHXAZ]

I have been assigned the task of running a new 100 pr cable from one building to another in an existing 2 inch conduit.
well I just tried pulling my nule tape with the exixting jet line and even with the couduit being empty the thing won't budge.
my guess is, that the pipe has either mud, dirt, or something living in it.
whats the best way to clean whatever is in there short of digging up the parking lot and running a new pipe.

 

[misseditbythatmuch]

How long is the run ?

Do you have access to a camera snake to take a look at the obstruction ? PVC or Rigid conduit ?

I once used a septic system contractor that specialized in old systems (like they had clay tile pipe) to clear a long run conduit with a solid obstruction.

He had a camera on a snake and could look at an obstruction. He also had a variable pressure water jet on another snake that could be very gentle or dialed way up to root cutting force. Yes, it puts some water in the pipe, but you can pump it or blow it out.

He cost a few bucks, but it was worth it to know exactly where the blockage was (he had a transponder on the end of the camera snake, so we could mark the earth above it accurate to within 2 inches +/-. It is good to know if you had a collapse of the conduit or some other total compromise before you try to pull anything.

 

[mforrence]

So, you have a line thru but it won't move? New or old pull? I'd put a shop vac on one end with suction and see if you feel air movement at other end. If no air, I'd try running a hose up the pipe and flush out. Or hire it out to someone who had a rodding rig.
Even with a perfect conduit, 2'' is snug for 100 pr duct, unless it is a very straight shot.
Mike

 

[alamtnman]

the trouble with a shop vac is if the conduit has a lot of water in it the vac may not move it

I have used a large co'2 tank (high pressure) to blow it out. I think we got them from local bottling company.

If you have someone you dont like have them on the other end looking down the conduit cause when the high pressure breaks free and shoots the water out( and all outdoor conduits will have water not matter who installed them)
it will cover them and it is nasty lol


T.R.
RCDD

there may not be any stupid questions
but their is a bunch of inquizative idiots
(myself included at times)