Pulling wire too hard or through too many bends

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Shawn4280

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Hi folks, I have been on job where the boss don’t believe in pull boxes. He had apprentices pulling 10 - #12THHN stranded through 3/4” emt over 100’ long and well over 360 degrees of bends. These apprentices were struggling it was a very hard pull. My question is can this hurt or damage the wire from the tension of the pull? And compromise the outer sheathing?
 
First, 360 degrees is the limit. So your boss is telling the workers to violate code. Secondly, yes, this can cause damage. The tension can cause the wires to snap. Also, rubbing the insulation against the inside of the conduit can scrape away some of the insulation.

Welcome to the forum.
 
10 stranded #12s in a 3/4 EMT isn't so bad if the nose is made properly and some pulling lube is used. Yes if there is more than 360° of bend it's a code violation but that doesn't mean that it will automatically damage the conductors.
 
infinity said:
Yes if there is more than 360° of bend it's a code violation but that doesn't mean that it will automatically damage the conductors.
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I agree because we have all done it at one time or the other and not turned into pumpkins and you will still see this in old building and still working just fine.

To be on the safe side it's cheaper to install a C-condulet as a pull point if needed and made things code compliant.
 
I’ve worked with a few guys who won’t spend the few extra dollars for pull boxes, LB’s or C’s. Also didn’t want to buy box extensions. Why spend that money when you can beat wire in with a hammer? It doesn’t really need a cover anyway if it isn’t in plain sight. I hated working with such guys & don’t miss them a bit.
 
Pulling over 360 degrees is done often to save time, but there’s a limit.
The stranded wire should have eased the pull, but I bet pulling soap was NOT used.
 
Shawn4280 said:
Hi folks, I have been on job where the boss don’t believe in pull boxes. He had apprentices pulling 10 - #12THHN stranded through 3/4” emt over 100’ long and well over 360 degrees of bends. These apprentices were struggling it was a very hard pull. My question is can this hurt or damage the wire from the tension of the pull? And compromise the outer sheathing?
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Running conduit with well over 360 can't be helped sometimes, but it usually takes very little effort to cut a pulling C in too when you need a pull point.

I never really understood why folks would run conduit like that, it usually only makes the pulling more difficult and sometimes the fishtape doesn't want to go through all the bends. Sets a bad example for the employees to follow too.
 
The code is the minimum requirement. For longer pulls IMO one should go easy on the bends and the pipe fill.

As others have stated, we have all been there, but I prefer to sleep soundly and not wonder if everything was pulled too tight and/or damaged in that last install.
 
BTW, the code only states you need a pull point every 360 degrees, it’s states nothing about pulling wire thru 400 degrees as being a violation.
 
jusme123 said:
BTW, the code only states you need a pull point every 360 degrees, it’s states nothing about pulling wire thru 400 degrees as being a violation.
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If that’s true, that’s kinda funny and I never thought about it. It makes you have the pull points there, but doesn’t mean you have to to use it...
 
Shawn4280 said:
Hi folks, I have been on job where the boss don’t believe in pull boxes. He had apprentices pulling 10 - #12THHN stranded through 3/4” emt over 100’ long and well over 360 degrees of bends. These apprentices were struggling it was a very hard pull. My question is can this hurt or damage the wire from the tension of the pull? And compromise the outer sheathing?
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The conduit run can be 300’ with no pull boxes and be code compliant, length has nothing to do with it. Some specs or company policies call for a pull point every100’, but it is not a NEC requirement
 
bwat said:
If that’s true, that’s kinda funny and I never thought about it. It makes you have the pull points there, but doesn’t mean you have to to use it...
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Some put the pull points in long strait runs (200’+) solely for the purpose of lubing the wire with soap (Pulling compound) as it passes by
 
My understanding is that even though the code specifies a maximum of 360 degrees of bend between pull points there is no prohibition of pulling straight through one or more pull points as long as the allowed wire tension and sidewall pressure on the conduit are not exceeded.

Putting in a pull point is relatively cheap even if the extra time and effort to pull at an extra point are not.
 
GoldDigger said:
My understanding is that even though the code specifies a maximum of 360 degrees of bend between pull points there is no prohibition of pulling straight through one or more pull points as long as the allowed wire tension and sidewall pressure on the conduit are not exceeded.

Putting in a pull point is relatively cheap even if the extra time and effort to pull at an extra point are not.
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That's true. With the run mentioned in the OP even if it had a pull point in the middle I would first attempt to pull it in one shot from the end. If it were too difficult then I would pull from the center pull point.
 
Do you know how to run pipe?
Do you know how to pull wire?
Do you know how to FEED wire?
100' isn't very long, how many degrees are you talking about?
 
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