Electrical Conduit Question

[Tractors4u]

Construction started today on our new house, at least they started digging the basement today. We chose to run the power line underground from the road. The local utility company set the pole at the road but the require me to dig a trench 4 feet deep, lay the conduit from the pole to the transformer pad and then cover it up. They will pull the cable through the conduit and connect it to the pole at the road. However to pull the cable through they require me to string a small rope through the conduit that they will use to pull a 5/8th diameter rope through which in turn will be used to pull the cable through. The conduit is 3 inch diameter, schedule 40 and comes in 10 foot sections. Question is, what is the best way to get my small rope through? I'm thinking of attaching the rope to a short piece of repar that I have and giving it a good shove through 10ft of pipe, glue the pipe, repeat and repeat. So what do you think? The engineer used the term "blow it in" a couple times, but I didn't get to ask him what he meant. Anybody know what he meant? I am gonna call him tomorrow and ask.

 

[SPIKER]

what is done is use a styro-foam plug which is blown through the pipe yhe plug is often called a PIG but a wad of light cloth wirks well too. use leaf blower to blow it into the pipe with a fish line attached (some 50 lbn pull at least, then use the fish line to pull in a heavier rope.) I used this technic to pull using the SUCTION side of my wood working dust collector to SUCK a rag & kite string through 180' of 4" coragated pipe. the smooth conduit should pull even easier.

anyhow the idea is set and easy to figure out shop vac usually does not move enough air, you need to move high volume of low pressure so compressor is not a good bet either.

MarkM

 

[GerardC]

When I ran the wire for my Video Phone from the driveway gate to the house (about 300 feet), I glued 4 pieces of conduit together at a time, ran my 50' wire fish through, pulled my wires 'til they came out, then glued another 4 pieces and pulled the wires through, at this point I glued the two 40' sections together and repeated the process until I was done. Worked like a charm.

 

[SCB]

I have been told to use a plastic grocery bag with the sting tied to it and then suck it through with the shopvac. I will be testing what I have been told soon. My run will only be about 120 feet. I think that my shopvac should have no problems.

 

[hobbyfarm]

Tractors4u,
Do you have a shop vac? Assemble the whole length and then vacuum the pull string through. (Greenlee #430) It takes no special plug to vacuum through. We typically use a Wal-Mart bag tied to your fish string. Once the light string is through the conduit, pull larger pieces of cord through. Usually Mule tape is the last thing left in the conduit. This is then ready for the utility company.
When you are using a vacuum on one end, have a helper feed the plug and provide slack. Also, on the vacuum end, get the best seal to the pipe you can. Vacuum until you hear the vac change tone from being plugged up. And you're done. Don't forget to tie off the string so it doesn't get pulled into the pipe.
To give you an idea, look at the <font color="green">Greenlee</font> product catalog on <font color="orange">Fishing/Cable Pulling/Material Handling</font> This PDF has the tools for this project.
This has a brief description of what you need to do: <font color="teal">Mule Tape</font>
This website has <font color="red">CablePulling Tape</font> (AKA mule tape)
Good luck!

 

[hobbyfarm]

</font><font color="blue" class="small">( When I ran the wire for my Video Phone from the driveway gate to the house (about 300 feet), I glued 4 pieces of conduit together at a time, ran my 50' wire fish through, pulled my wires 'til they came out, then glued another 4 pieces and pulled the wires through, at this point I glued the two 40' sections together and repeated the process until I was done. Worked like a charm. )</font>

GerardC,
Boy, that's the hard way. The technique I described above always works. I've pulled a wally-world bag through 750' of 4" conduit with no problem. It didn't take two minutes start to finish! It always takes more time to setup than to do the job.

 

[Soundguy]

Y ou are getting good advice. When we lay chase pipe for audio cable.. we blow a thin string thre. .the small plug with the line attatched to it works great.. then you pull a heavier cord thru.. then the wire..

Common practice...

For shorter runs.. steel tape fish / snakes also work.

Soundguy

 

[GerardC]

<font color="blue"> GerardC,
Boy, that's the hard way. The technique I described above always works. I've pulled a wally-world bag through 750' of 4" conduit with no problem. It didn't take two minutes start to finish! It always takes more time to setup than to do the job. </font>

Would this technique work well on 1/2" diameter conduit? That's what I used as the wire is door bell wire.

 

[Freds]

The electrician that wired my business layed all the conduit in the trench and used a small weight on the end of a string. He would lift one end of a 10' section, put the weight in and let it slide out the other end. The he would fit the pipe, but I don't remember if he glued it.
When I ran my driveway sensor in underground conduit I sucked the string through with a shop vac. It came through without needing a bag, plug or anything.
I am just amazed that they will pull the wire for you. The electric company here had us pull the wire and leave enough at the bottom of the pole for them to hook up. It was no easy task pulling that wire, but they probably use a winch or something.

 

[BB_TX]

I wondered the same thing when I had conduit run from a pole about 150' to my building. My neighbor was an old TXU lineman. He told me to bring him a tennis ball, some nylon cord, and my shop vac. He wrapped the cord around the tennis ball (which just happen to be the right size to go thru the conduit), put a little tape on it to hold the cord, and told me to feed the cord as it pulled thru. He took the shop vac to the other end (had a temporary power plug at the pole), put the hose to the conduit, wrapped a rag around it to seal it and turned the vac on. I actually got rope burns from the cord sliding thru my fingers so fast. /forums/images/graemlins/blush.gif
That was all the power company needed. They used the nylon cord to pull their pull rope thru the conduit.