[TowerTalk] burying conduit Re: TowerTalk Digest, Vol 224, Issue 15

[Steve Davis | Davis RF]

burying conduit vs pulling when (STEPHEN L SALA)


Steve,

What is the make and part # of the cable   ?
What OD is the cable   ?
What is the ID of the conduit  ?
What type of bends (angle)    ?


Without knowing these answers, but assuming the ID is  at least twice the OD of the cable, and with sweeping bends vs. right angles (you need to know the min. bend radius of the cable and limit the bends to that), then I would say run a rope thru the sections as you cement them together, let he cement set, then pull the cable thru.

Running the cable thru ea section , and gluing, not a good idea. The cement won't effect the electicals but you are apt to cement the cable inside the conduit.

Most commercial insallations are done with the cable buried first, then pull thru.   But not an issue if you want to pulll it thru the conduit, right next to the  ditch, then roll it in and back fill.

Also, you can put both ends of the conduit slightly below the middle. Drill holes in bottom of conduit on each end and allow to leach out moisture into a small gravel dry well of sorts under the hole.   This assumes a water table will not get as high as the conduit.  But if you are using certain cables, like RFS or Heliax, the outer conductor is PE, impervious to water, oil, gas and certain chem's.

Having said all that, it is best if you tell me the above info so I can better address the application.

73  Steve,   K1PEK   DAVIS RF Co.       DAVIS ROPE and Cable Assembly, LLC



Message: 1
Date: Sun, 15 Aug 2021 18:25:39 +0000
From: STEPHEN L SALA < >
To: "towertalk at contesting.com" <towertalk at contesting.com>
Subject: [TowerTalk] burying  conduit vs pulling when
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I see that there several methods of putting heliax, coax, and control cables in conduit (a pair of 3 or 4 inch PVC) buried in the ground.


  1.  Glue ten foot sections together as you pull the cables through each ten foot section and then bury it all.  Might get glue on cables?
  2.  Glue  the entire conduit first  together and leave it unburied until the cables are pulled, then bury conduit.  Because there is no weight of dirt on the conduit, does that method affect the pulling  on the conduit structure?
  3.  Glue the entire conduit run together, but then bury it before pulling cables.  the burying of the conduct first should keep the conduit from coming apart or out of the ground?

Since my trenches are in fractured basalt, but already dug, and I have gophers/voles in that area that mess up the open trenches now, I probably will do the following:

Lay down about 1 inch of sand to even out the trench bottoms.
Install conduit(s)
pour a few bags of gopher repellent around the conduit
Fill in trench with 5/8 crushed gravel, then an inch of dirt on top so it looks like the land around it.

Any comments please?


73
Stephen Sala K7AWB


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