Cable Pulling

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faresos

Senior Member
I'm working on a very large building (about 900ft Long) and the service entrance equipment is located at the corner of the building. I have a veruios cables to run, the cable sizes varies from #3 to #500kcmil. My question is, can we pull those cables (underground in PVC conduit) without having any handholes or manholes? Those runs will not have more than (3)-90 degree bends and the longest run is about 900ft.

Thanks for your thoughts..
 

roger

Moderator
Staff member
Location
Fl
Occupation
Retired Electrician
Yes, they can be pulled that distance but it will take some serious equipment and people experienced in these type of pulls. (a pull of this length and size is not a task to take on for learning the ropes)

The contractor perfoming the work should have some input.

If I had a choice I would put at least 2 pull points in runs of this distance.

Roger
 

bob

Senior Member
Location
Alabama
faresos said:
I'm working on a very large building (about 900ft Long) and the service entrance equipment is located at the corner of the building. I have a veruios cables to run, the cable sizes varies from #3 to #500kcmil. My question is, can we pull those cables (underground in PVC conduit) without having any handholes or manholes? Those runs will not have more than (3)-90 degree bends and the longest run is about 900ft.

Thanks for your thoughts..
You can not make that determination with out making the PULLING CACULATIONS. The 3 90's complicate the problem.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
PVC 90s are often a problem in this type of pull even where the pull calculations say that the wire can be pulled without damage.
Don
 

faresos

Senior Member
don_resqcapt19 said:
PVC 90s are often a problem in this type of pull even where the pull calculations say that the wire can be pulled without damage.
Don


I always use GRC 90's when I run PVC, that way it won't damage the 90 degree elbow.
 

ramsy

Roger Ruhle dba NoFixNoPay
Location
LA basin, CA
Occupation
Service Electrician 2020 NEC
faresos said:
I always use GRC 90's when I run PVC, that way it won't damage the 90 degree elbow.

Wish I knew which type of pull rope does not burns thru PVC like butter. I might consider such rope with long PVC sweeps, rather than GRC 90's. Either way I believe lots of lube, and simultaneous pushing with the pulls can improve the pull-force calcs.
 

John Valdes

Senior Member
Location
SC.
Occupation
Retired Electrician
Use a tugger or get several people on each end. I also would use two pull boxes for this distance. Three 90s? I hope you have some way to blow or suck a string through this conduit. Then pull your rope in. LUBE, LUBE, LUBE.
 

don_resqcapt19

Moderator
Staff member
Location
Illinois
Occupation
retired electrician
faresos,
I always use GRC 90's when I run PVC, that way it won't damage the 90 degree elbow.
How do you make the required bonding connection to the GRC 90?, or are they always under 18" of earth or 2" of concrete?
Don
 

mdshunk

Senior Member
Location
Right here.
It helps some to pull a lube saturated swab through the pulls that you know will be hard. PVC 90's in long heavy runs?? Eeek.. that sends chills down my spine. I've burned through my share of PVC 90's until I learned my lesson. Hate to suggest it, because it sorta screws things up for the next guy, but if you lube your rope up good too as you pull it through with your pull string, that works better too. Takes a couple extra wraps on the tugger capstan though to get good traction with a lubed rope.
 

tonyou812

Senior Member
Location
North New Jersey
why would you want to stress yourself like that? is there any reason for no pull points? 3 90's on a run like that would require a bit more than the ol "station wagon"
 

Davis9

Senior Member
Location
MA,NH
I watched a local utility pull in some primary cables(long runs) and they used some sort of lube bag on the head of the wire. I think they had on attached farther up the rope as well, maybe this would help.

Tom
 

hardworkingstiff

Senior Member
Location
Wilmington, NC
I'd rather pull the long run than work the pull boxes. If you don't make joints in the pull boxes, I don't believe you gain much (and actually I think it is more work).

That Greenlee Ultra Tugger will do a powerful amount of work. Like others have stated, make sure the pulling calculations work out before roughing in the conduits. Make sure they stay clean and clear. Experienced workers with proper equipment should have no problem.

Tugger, feeder, radios, lube, lube, lube, men, men, men. Make sure everyone understands how the whole pull will go prior to starting and you should be fine. Planning is everything (starting before the rough-in).
 

mdshunk

Senior Member
Location
Right here.
hardworkingstiff said:
Make sure they stay clean and clear.
I've been picking away at making a company standards book. I do have "all conduits shall be swabbed to clear potential debris prior to pulling" as one of them. I'm constantly amazed at how gravel, cans, and cigarette butts, and human waste end up in conduits.
 

Tori

Senior Member
Location
Maryland
I have much experiance in this area. Pre pulling lube is a bad idea because your rope will be worthless on the tugger. three 90 s are nothing - lol pulled through many more than that -straight through J boxes , manholes etc.
you have to consider the forces involved , bracing boxes , chaining pipe at stress points, the tugger can pull 10,000 pounds of pressure, red lines at 7000,, tuggers in series , winches, things start groaning and popping at that kind of pressure, ropes need to sized right, tuggers need to be moutd SECURELY - this is NOT for a first timer -
people can be hurt, equipment can be damaged.
Make sure you tie the basket correctly or we will be pulling the wire out -BAD -VERY BAD- they do have some newer methods of securing the cables, like little missles that are staggered and secure the wire and upon pressure dig into the copper itself.
I have seen enough go wrong and some terrifying stories of bad pulls to know how to do it . Notice I did not say the correct way or safe way -everyone is different and everyones degree of safety is different.
They have some mechanical feeders out there can be rented -worth the money can take the place of 4 men when pulling 500 mcm and up.
Stay safe !!
 

Smart $

Esteemed Member
Location
Ohio
hardworkingstiff said:
I'd rather pull the long run than work the pull boxes. If you don't make joints in the pull boxes, I don't believe you gain much (and actually I think it is more work).
Hand holes are put in long, fairly straight runs quite often simply for access, not as pull points... unless absolutely necessary. In swabbing the run, these allow for major debris if any to exit without traveling the entire length. The farther debris has to travel, the more likely the swab will pass over it along the way. Access also provides additional lube points. Entering and exiting conduits should be exactly inline across from each other.

Here's a jobsite I was on a few years back.

panorama.jpg


Among other things, we put in a new underground 12kv loop around the facility. Unfortunately, the downsized image loses it's grandness.
 

Nick

Senior Member
I have to disagree with the pre lubing and lubing the rope. I tried it once on a difficult pull using an ultra tugger. I had every wrap on the capstan it would take and all the force I could muster to get the rope to grab. The Polywater bags you tie on the rope at the head look like a much better option.
 
Use lots of lube

Use lots of lube

This sounds like a tough pull, I don't know how many of these conductors you are pulling or what size the conduit is, but if you are maxing out the limitations of the allowable conduit fill you will have your work cut out for you with no middle pull points. In my experience with these types of pulls the best type of lube is dynalube. You can get it in 5gal. pales and it works great.
 

e57

Senior Member
Steel 90's on super-sized conduit, and I will second (or third) not lubing the rope... Have some beer on hand for AFTER, it's gonna be a long day... (or two)
 
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