Minimum distance between sweeps in pvc conduit?

[10fords]

Is there a table or code specification for the minimum distance between 90 degree sweeps? I would like to have something to refer to when I make a tractor guy dig up their conduit because I can't get wire pulled through them, and I have been unable to find anything, other than common sense, that dictates this. Thanks from a first time poster- Scott

 

[qcroanoke]

Is there a table or code specification for the minimum distance between 90 degree sweeps? I would like to have something to refer to when I make a tractor guy dig up their conduit because I can't get wire pulled through them, and I have been unable to find anything, other than common sense, that dictates this. Thanks from a first time poster- Scott

Code allows only 360 degrees of bends in a run between pull points. How far between 90's is not discussed.

 

[petersonra]

Is there a table or code specification for the minimum distance between 90 degree sweeps? I would like to have something to refer to when I make a tractor guy dig up their conduit because I can't get wire pulled through them, and I have been unable to find anything, other than common sense, that dictates this. Thanks from a first time poster- Scott

as long as they followed the specs and/or instructions they were given, what basis is there to have them rip it out without someone paying them to do so.

 

[ActionDave]

What's the application? What size wire? What size pipe? How long of a pull?

Back to back nineties may a little difficult to pull through but not impossible.

 

[10fords]

as long as they followed the specs and/or instructions they were given, what basis is there to have them rip it out without someone paying them to do so.

Generally there are no specs as most of my work is on privately owned ranches. If I am consulted first there is rarely a problem.

 

[10fords]

What's the application? What size wire? What size pipe? How long of a pull?

Back to back nineties may a little difficult to pull through but not impossible.

The application is usually either service to a well, or a residence from the meter somewhere on the property. Wire and pipe size vary according to distance, and most of my pulls are fairly long. (just finished a 1400 foot one yesterday).

I'm well aware of the 360 degree rule, and quote it often when explaining to owners or tractor guys why I can't use the conduit they put in "as is", and was hoping there was something similar regarding distance between sweeps.
It appears that there is no NEC rules governing this though.:?:? Thanks- Scott

 

[don_resqcapt19]

...
It appears that there is no NEC rules governing this though.:?:? Thanks- Scott

Only 110.3(B), if the raceway design results in a pulling force and/or sidewall pressure that exceeds what is permitted in the manufacturer's instructions.

 

[Cow]

Are there no permits or inspections where you're at? I'm curious how farmers are laying conduit and backfilling without anyone looking at it first?

 

[10fords]

Are there no permits or inspections where you're at? I'm curious how farmers are laying conduit and backfilling without anyone looking at it first?

I wish! But I have never seen an inspector fail any installation based on the distance (or lack of) between sweeps. They don't have to pull the wire in!

I think I can conclude that as long as you are on the customer side of the utility there is no code governing distance between sweeps. I kinda hoped I had missed something in my search of the NEC so I could quote a code when I was faced with an unpullable situation, to counter the "we always do it this way" argument!

 

[ActionDave]

I wish! But I have never seen an inspector fail any installation based on the distance (or lack of) between sweeps. They don't have to pull the wire in!

I think I can conclude that as long as you are on the customer side of the utility there is no code governing distance between sweeps. I kinda hoped I had missed something in my search of the NEC so I could quote a code when I was faced with an unpullable situation, to counter the "we always do it this way" argument!

Stinker of a spot to be in when a pull goes bad, I agree....
I'm not seeing how two nineties too close together adds up to an unpullable situation though.

 

[J.P.]

Had a led billboard in front of an insurance company once.
The mason installed pipe when he built the fancy rock pedestal for the sign.

1/2" pvc thinwall water pipe with 3 water pipe 90's.......... It stubbed out horizontal about 2" under the sod. Perfect.

I wish they would have called before they had the fancy stonework done. I could have made my life so much easier.

For you situation you could install back to back to back to back 90's and pull boxes the whole distance is you were sadistic enough to do so.

Any possibility on renting a trencher and installing your own pipe on these jobs?

 

[Dennis Alwon]

I would not be surprised if they used a plumbing elbow. I have seen this many times. You cannot pull thru them or even get a fishtape thru,

 

[10fords]

Had a led billboard in front of an insurance company once.
The mason installed pipe when he built the fancy rock pedestal for the sign.

1/2" pvc thinwall water pipe with 3 water pipe 90's.......... It stubbed out horizontal about 2" under the sod. Perfect.

I wish they would have called before they had the fancy stonework done. I could have made my life so much easier.

For you situation you could install back to back to back to back 90's and pull boxes the whole distance is you were sadistic enough to do so.

Any possibility on renting a trencher and installing your own pipe on these jobs?

Been there many a time! I have a ride on ditchwitch that I use when possible, but most of the terrain in these parts requires a 4x4 backhoe.

I'm negotiating a job right now where the general contractor ran conduit from the house to the wellsite with at least 8 sweeps in a 300 foot run! He claims he can get the wire in for me no problem!

 

[growler]

Are there no permits or inspections where you're at? I'm curious how farmers are laying conduit and backfilling without anyone looking at it first?

I'm curious as to why there would be back to back 90s on an underground conduit run.

 

[Strathead]

I am just trying to figure out how this is an issue. I have, on occasion had a hard time getting a fish tape in a conduit with 90's too close to each other, especially at the far end of a run, but I have never had a problem with pulling once the rope is in, that I would attribute to the number of bends. Flattened elbows, yes, bends too tight, yes, rocks in the pipe, yes, oh a cell phone in a pipe, yes, but back to back 90's I suggest you get a better tugger, rope, or soap.

 

[Carultch]

DELETE POST PLEASE

 

[GerryB]

I'm curious as to why there would be back to back 90s on an underground conduit run.

Was thinking the same, and if there were back to back 90's you would think they would be at an end where you could catch the snake with another one.

 

[10fords]

I'm curious as to why there would be back to back 90s on an underground conduit run.

You and me both! The only reason I can think of is that when they run waterlines it doesn't matter how many 90s you have or how close they are to each other. Other than that I have no idea why.

 

[10fords]

I am just trying to figure out how this is an issue. I have, on occasion had a hard time getting a fish tape in a conduit with 90's too close to each other, especially at the far end of a run, but I have never had a problem with pulling once the rope is in, that I would attribute to the number of bends. Flattened elbows, yes, bends too tight, yes, rocks in the pipe, yes, oh a cell phone in a pipe, yes, but back to back 90's I suggest you get a better tugger, rope, or soap.

Any suggestions on a good tugger for use in the dirt? Normally I use human power or maybe a quad if it is a long pull with heavy wire. Other than that I was taught that if you need to hook a backhoe to your pull you didn't set it up properly and could overstress the wire or break the conduit. One time we used a truck on a 400 ft pull of 3@ 500mcm in a 3 inch conduit and the friction of the mule tape sawed through a sweep! I would like to hear what guys are using as I am getting older and don't have the endurance anymore for heavy pulls like I used to. I am a mostly 2 man operation with additional help when necessary so $50,000 machines aren't practical for me (assuming I could get them into where I need them).

 

[Cow]

I would try one of those maxxis tuggers that slip onto the conduit you're pulling out of. I haven't used one personally but they look like they'd work well.