directional drilling

[Ponchik]

I have a project that needs about 600 feet of PVC conduit to be installed under ground for a feeder out to a detached building.

I am assuming directional boring will work for this project because we have a wide open space. However, I don't know how the PVC conduit will get installed properly. I guess once the boring head pulls back it will pull the conduit with it and the electrician has to glue the PVC as it is being pulled??

Thanks for your replies.

 

[Buck Parrish]

I don't think they use sections of conduit. All the guys I know have large rolls of plastic conduit. But that's just me. That's such a good method. Because of the areas that I work. It's likely I have missed out on a whole new world of burial conduit.

 

[don_resqcapt19]

There is PVC made for that application and it has a locking ring. Often HPDE conduit (Article 353) is used for directional boring applications. It is a long length on a spool and there will be no joints in the run.

 

[kwired]

Directional boring crew can pull anything you want back through their hole. If you glue PVC together as it is being pulled in you may very well find joints that are not set or not strong enough for the pulling tension though. This is a case where if using standard PVC you may be better off using primers and slower setting cement just to get stronger joints, but 600 feet will require a pretty fair pull tension and maybe best to use PVC designed for the purpose or a continuous piece of HDPE. Remember the HDPE will only be allowed for the underground portion of the run and you will need to adapt to some other raceway method before emerging on both ends. Also note that though PVC fittings do fit the HDPE and sometimes are used - they are not listed for that use. There are fittings out there listed for use with HDPE.

 

[E16]

Directional boring crew can pull anything you want back through their hole. If you glue PVC together as it is being pulled in you may very well find joints that are not set or not strong enough for the pulling tension though. This is a case where if using standard PVC you may be better off using primers and slower setting cement just to get stronger joints, but 600 feet will require a pretty fair pull tension and maybe best to use PVC designed for the purpose or a continuous piece of HDPE. Remember the HDPE will only be allowed for the underground portion of the run and you will need to adapt to some other raceway method before emerging on both ends. Also note that though PVC fittings do fit the HDPE and sometimes are used - they are not listed for that use. There are fittings out there listed for use with HDPE.

:thumbsup::thumbsup:

If we had them pull in PVC we would glue it all together the day or so before to make sure it set up well. But we never did anything that long. I would agree with the HDPE in this application. Good Luck

 

[Ponchik]

Thanks for your informative replies.
I will call some companies for pricing.

 

[kwired]

Whoever you hire for directional boring likely can or will want to supply the HDPE. That is what they do, and it is usually automatic that they will install HDPE, they just need to know what size you want installed. But as mentioned they can pull just about anything that will fit in the hole. They also likely have the equipment for hauling/dispensing it, that equipment is pocket change compared to some of what they have.

There are HDPE assemblies out there with conductors already installed in them - this can be labor saving, especially for directional boring applications, but they work great for instances where you are plowing the line in instead of trenching as well.

 

[don_resqcapt19]

We did an install where they pulled a 1 1/4" rigid conduit through the bore hole. The conduit separated at a coupling while it was being pulled. The male threads just pulled out of the conduit coupling. The conduit couplings were replaced with plumbing couplings and the pull was completed without additional problems.

 

[ceb58]

I have a guy that is going to do a 100 ft run for me next week. He will go under a parking lot and side walk with 1 1/4" and I will pick up and complete the direct bury on each end. $1800.00 which I didn't think was all that bad

 

[Cow]

I would look into HDPE for boring. I haven't done electrical boring but HDPE is what all the communication guys use(those big orange reels). I would think a good boring contractor would be able to tell what would work best.

What would be really slick for you is Cablecon. It's HDPE with wires preinstalled in it. We use a TON of it for crop circles. Our local irrigation supply is where we get it from. If your boring contractor could pull this in, and pull it out long, so you have enough wire length you'd be way ahead of the game.

I have a guy that is going to do a 100 ft run for me next week. He will go under a parking lot and side walk with 1 1/4" and I will pick up and complete the direct bury on each end. $1800.00 which I didn't think was all that bad

That seems like a good price to me. I think my boss called on some boring a while back and was quoted around $23/ft.

 

[curt swartz]

For all of the job I have done with horizontal boring I tell the boring contractor what size raceway I need and they supply the material. I prefer this way so Its 100% their responsibility. Most jobs they have supplied HDPE but I have done a few jobs where they supplied 3" PVC.

Most of the time if running between building gas and water service will also be required. The GC will usually just sub all runs out to one contractor.

I have not been real impressed with the PVC to HDPE transition connectors. I usually just set Christy boxes (concrete hand holes) at each end then run PVC from there.

 

[Cow]

I have not been real impressed with the PVC to HDPE transition connectors. I usually just set Christy boxes (concrete hand holes) at each end then run PVC from there.

This is what we use when doing cablecon to pvc transitions. I like them. They have a an o-ring inside them and go in TIGHT. Then when you cinch down the hose clamp there is no way they are coming apart.

http://www.duraline.com/category/accessories-store/couplers/shur-lock™-ii