help with pulling calc

[electrofelon]

So due to all the material availability/cost issues, Ive got something unconventional brewing. IVe got about 1900' of 15kv CN primary to run. How far can I pull this in 1.5" SDR 17 conduit? The run would be essentially straight, just maybe 30 degree of very gradual bend. The cable is pretty much an inch on the money and .54 pounds/foot. Anyone got experience with something like this and/or can run the calc for me? I can get the SDR with a 1000# tape installed. How much length will that get me? I have pulled around 800 feet, but cant recall ever breaking the 1000' barrier......

 

[masterinbama]

I would set two pull points in this run. That would give you 3 roughly 650' pulls.

I would use above ground sectionalizing cabinets with spare conduits stubbed out for future use.




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[electrofelon]

I would set two pull points in this run. That would give you 3 roughly 650' pulls.

I would use above ground sectionalizing cabinets with spare conduits stubbed out for future use.




Sent from my moto e using Tapatalk

I had considered breaking it into two or three sections.

 

[Cow]

If the cable is 1" OD, I would not run anything smaller than 2".

We've done pulls up to 1600', but we usually break them up if they are over 1000'. I haven't pulled MV cable at long distances, so I can't speak to specifics on that. It always been thhn, xhhw, or similar on our long pulls.

My gut says if you only have 30 degrees of bends overall, I'd probably put one pull point/sectional/vault in the middle. Should be two easy pulls at 950'.

 

[Hv&Lv]

So due to all the material availability/cost issues, Ive got something unconventional brewing. IVe got about 1900' of 15kv CN primary to run. How far can I pull this in 1.5" SDR 17 conduit? The run would be essentially straight, just maybe 30 degree of very gradual bend. The cable is pretty much an inch on the money and .54 pounds/foot. Anyone got experience with something like this and/or can run the calc for me? I can get the SDR with a 1000# tape installed. How much length will that get me? I have pulled around 800 feet, but cant recall ever breaking the 1000' barrier......

Any bends at all on beginning or end? Lube? The 30 degree of bend, it’s just a slow gradual sweep over a large distance? Say 8-900’? Any grade? Positive. Uphill or downhill.. Just a simple straight pull comes up to about 454 lbs.

FWIW, I’ve pulled in >1200’ of 1/0 XLPE JCN cable with a bend at each end. Set up properly with a guy at the beginning pulling it off the reel and another helping it in the pipe with a little push. The pull went very easy and was done in about 10 minutes.

 

[electrofelon]

If the cable is 1" OD, I would not run anything smaller than 2".

We've done pulls up to 1600', but we usually break them up if they are over 1000'. I haven't pulled MV cable at long distances, so I can't speak to specifics on that. It always been thhn, xhhw, or similar on our long pulls.

My gut says if you only have 30 degrees of bends overall, I'd probably put one pull point/sectional/vault in the middle. Should be two easy pulls at 950'.

That was my first gut thought was put a pull point in the middle.

 

[electrofelon]

Any bends at all on beginning or end? Lube? The 30 degree of bend, it’s just a slow gradual sweep over a large distance? Say 8-900’? Any grade? Positive. Uphill or downhill.. Just a simple straight pull comes up to about 454 lbs.

FWIW, I’ve pulled in >1200’ of 1/0 XLPE JCN cable with a bend at each end. Set up properly with a guy at the beginning pulling it off the reel and another helping it in the pipe with a little push. The pull went very easy and was done in about 10 minutes.

There is some gradual undulation in the terrain, but yes very long gradual sweeping bends over hundreds of feet. I'd be willing to pull straight in and out at the ends to avoid sweeps there. I know the SDR is pretty smooth inside, I would likely use lube just to be safe.

 

[Fred B]

There is some gradual undulation in the terrain, but yes very long gradual sweeping bends over hundreds of feet. I'd be willing to pull straight in and out at the ends to avoid sweeps there. I know the SDR is pretty smooth inside, I would likely use lube just to be safe.

Question, so when you have these gradual bends like you describe, do they count into the max degrees of bend allowed between points?

 

[Dell3c]

So due to all the material availability/cost issues, Ive got something unconventional brewing. IVe got about 1900' of 15kv CN primary to run. How far can I pull this in 1.5" SDR 17 conduit? The run would be essentially straight, just maybe 30 degree of very gradual bend. The cable is pretty much an inch on the money and .54 pounds/foot. Anyone got experience with something like this and/or can run the calc for me? I can get the SDR with a 1000# tape installed. How much length will that get me? I have pulled around 800 feet, but cant recall ever breaking the 1000' barrier......

Having a hand in MV pull (500's in parallel) about 2(+) yrs ago, pull was somewhere, just under 2600ft @ data center. Seems the pull point(s) somewhere in neighborhood 550-600ft. Employed use of cable pusher(s) between set pull points. No splices were allowed in cable.

 

[electrofelon]

Question, so when you have these gradual bends like you describe, do they count into the max degrees of bend allowed between points?

Theoretically yes.

 

[electrofelon]

Having a hand in MV pull (500's in parallel) about 2(+) yrs ago, pull was somewhere, just under 2600ft @ data center. Seems the pull point(s) somewhere in neighborhood 550-600ft. Employed use of cable pusher(s) between set pull points. No splices were allowed in cable.

This cable is relatively light, it's a number two aluminum with a concentric #4 copper...... And a bunch of plastic

 

[ramsy]

I can get the SDR with a 1000# tape installed. How much length will that get me?

Can it be ordered with two 1000# tapes installed?

 

[electrofelon]

Can it be ordered with two 1000# tapes installed?

I am not sure.....I could of course pull in a stronger tape, not really a huge deal in the scheme of things I guess.

 

[Dell3c]

This was AL also. The cable reels, standing about 8ft tall. One 90 degree sweep, between vault @ street and first straight run(s) along long entry driveway, to the data center. Cable manufacturer would certify cable, up to certain tension (max) during the pull. Had to employ use of pull tension meter during pull, which recording the max pull tension, during pull(s). Cable was very heavy with "wraps" on reels, and concerns were about "cable flatting" on the inner wrap(s) of the reels.

 

[electrofelon]

This was AL also. The cable reels, standing about 8ft tall. One 90 degree sweep, between vault @ street and first straight run(s) along long entry driveway, to the data center. Cable manufacturer would certify cable, up to certain tension (max) during the pull. Had to employ use of pull tension meter during pull, which recording the max pull tension, during pull(s). Cable was very heavy with "wraps" on reels, and concerns were about "cable flatting" on the inner wrap(s) of the reels.

I thought a saw a figure for this cable that said allowed pulling tension was 350#, but I cant for the life of me find it now. Seemed a bit low to me.

 

[Hv&Lv]

There is some gradual undulation in the terrain, but yes very long gradual sweeping bends over hundreds of feet. I'd be willing to pull straight in and out at the ends to avoid sweeps there. I know the SDR is pretty smooth inside, I would likely use lube just to be safe.

Ok.
1900*.54= 1026 lbs
1026 * .5(cof of well lubed pvc) = 513lbs. That is for a flat conduit with no bends, therefore no sidewall pressure.
Weight correction factor will be 1 since there is only one cable in the conduit. Also no jam factor since there is only one cable.
The only thing that would make it easier is bigger conduit. The conduit inside diameter is close to the cable outside diameter, so there is more surface area between the cable and the inside of the pipe. A 2” pipe would be less surface area..

 

[Hv&Lv]

I thought a saw a figure for this cable that said allowed pulling tension was 350#, but I cant for the life of me find it now. Seemed a bit low to me.

That’s probably right. What size cable?

#2 AL (hard) is 66360 cmil stress is something like .005.
That’s 331 lbs
I got a book somewhere, I’ll look for it

 

[Dell3c]

I don't remember, the pull tension (set allowance) on these pull(s). But having take pull-meter into office, for download & recording afterward of the pull(s). On a personal note, I'd certainly look into "cable pushers" along a 1900ft pull-run.

 

[electrofelon]

That’s probably right. What size cable?

#2 AL (hard) is 66360 cmil stress is something like .005.
That’s 331 lbs
I got a book somewhere, I’ll look for it

Thanks! #2 Al 15KV URD, full neutal. I can certainly go bigger on the conduit, although fairly big price jump and would have to dig more to get the length with 2". I think Id rather go 1.5" and break into 2 or three pulls.

 

[Hv&Lv]

Thanks! #2 Al 15KV URD, full neutal. I can certainly go bigger on the conduit, although fairly big price jump and would have to dig more to get the length with 2". I think Id rather go 1.5" and break into 2 or three pulls.

I would also. At least in half..

In looking I realized I gave the book to the guy that took over my crew many years ago. He “borrowed” if about 5-7 years ago.
Probably never get it back now...

I did manage to find it online.

https://www.anixter.com/content/dam/Suppliers/Southwire/Literature/envirotectPowerCableInstallManual.pdf