Long conductor pull

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nickelec

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Good evening all I have a project coming up where I need to pull 2500' of 250mcm for a feeder.

This is longer the anything I've ever done. Any advice, tips, things to consider?

I'm thinking of doing it in two maybe three pulls and splicing it

I'm assuming a roll of 1250' of 250s would be extremely hard to handle .

Braking it down to 500 or 600 foot pulse may be a bit easier to manage logistically


I also don'tknd renting a truck for a wire reels of you all think it could be done in one pull

Come to think of it I don't think iwv seen pulling ropes longer then 600. Can you put two together? I've never done that..

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There is pulling software from south wire that will tell you how long a pull can be done based on wire, bends etc.
we have many here who have done similar pulls, wait for those comments
 
As Tom said, you need to do a pull calculation. If this is mostly straight, you can probably do it without an issue. If there are 90s, especially near the pulling end of the pull, you will likely have issues with the sidewall pressure part of the pulling calculation. That is the crushing force placed on the conductor insulation as the pulling force pushed the conductor against the inside wall of the bend. You can reduce this crushing force by using a larger radius bend as the crushing pressure is the pulling tension in pounds divided by the radius of the bend in feet.


I always try to avoid splices if there is any way to do that. At times you would set up the spools at a manhole near the center of the run, pull one direction off the spools, then take the rest of the wire off the spools and lay it out and then feed the other end in. There is risk every time you handle the wire and this method takes a lot of manpower to avoid conductor damage. It becomes a judgement on the part of the installer to do this or to make a splice.

Also check the specs, as sometimes they are written to prohibit splices.
 
I'd say it depends. I agree with Don if it's straight and a pretty good non wavy trench bottom, I think one pull would be no problem. I remember this time we pulled about 700 feet of 500 URD in 4". We left the ends not made up so it was all straight except for very long gradual bends , no 90's. After we pulled it in we thought out of curiosity let's just see if we can pull it by hand. Two of us pulled it quite easily. If you start getting into a crappy uneven trench and 90s or bends in the run it can be a whole different ball game in friction intention can add up extremely quickly and you're going to want to be careful and/or do a calculation, break up the pull etc.

On Long pulls like this, watch out for the rope chewing through '90s.

If you want to break it up, an alternative to having a vault or hand hole is to leave say a 10-ft break where you're going to repull, and sleeve a larger piece over (maybe in your case 3 1/2 inch?) To sleeve over once you've pulled the wire back through.
 
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