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Electronics => Beginners => Topic started by: mike_mike on October 17, 2022, 04:56:19 pm

Title: cables blocked in corrugated tube
Post by: mike_mike on October 17, 2022, 04:56:19 pm
Hello! My problems is the following: I have a 25mm diameter and 5m length corrugated tube installed into concrete. I tried to introduce from one end to the another end of the tube 3 cables: one UTP cat 6, one coaxial cable for tv and a 3x1mmp cable for powering a router. When I installed the cables into the tube, the cables blocked and I used wd40 to lube at both ends in order to pull out the cables.
If I install now only 2 cables: the UTP cat 6 one and the coaxial one, then the WD40 that remained into the tube can harm the 2 cables ?
Title: Re: cables blocked in corrugated tube
Post by: strawberry on October 17, 2022, 05:03:42 pm
insert wire puller wire
Title: Re: cables blocked in corrugated tube
Post by: mike_mike on October 17, 2022, 05:22:51 pm
insert wire puller wire
I used wire puller wire. But the cables blocked at the tube bend.
 
Now I managed to pull them out, but I don't know if WD-40 does any harm to coaxial cable (triple shielded) and UTP cat 6 ?

I found that the coaxial cable (triple shielded) have Polyvinyl chloride coating and the UTP cat 6 have fire retardant pvc coating.

Title: Re: cables blocked in corrugated tube
Post by: strawberry on October 17, 2022, 05:54:22 pm
WD-40 may evaporate. dont know what it will do to plastics(oils might make softer). not saw problems with it... except acetone, gasoline,..
Title: Re: cables blocked in corrugated tube
Post by: jpanhalt on October 17, 2022, 06:26:56 pm
I would not use WD40.  What you  want is cable pulling lubricant available at every home improvement store.  It is basically a soap emulsion.  Some leave a residue, which is no big deal.  I typically use the Ideal brand or a yellow paste for which I don't remember the name.  Most recently, I tried a spray foam by Klein tools.  It worked OK for pulling Romax through holes in rafters, but when I pull wires through conduit (as you are doing), I think I would go with a gel or paste.

Remember it is easier to pull cooked spaghetti than to push it.  Same goes for wires.

Title: Re: cables blocked in corrugated tube
Post by: floobydust on October 17, 2022, 06:31:32 pm
OP, you're supposed to use cable soap  :P
WD-40 is mostly kerosene (jet fuel) and no good for many plastics. But it does evaporate fast, so if the conduit has some airflow allowing it to evaporate. It does have a tiny amount of some mineral oil in it as I recall.
If you bolt on the covers and trap the liquid in there, it will attack the cable's plastics.
Title: Re: cables blocked in corrugated tube
Post by: themadhippy on October 17, 2022, 07:22:57 pm
Quote
cable soap
which of course we all use,never a bit of fairy liquid or the tallow we use when cutting conduit
Title: Re: cables blocked in corrugated tube
Post by: jonpaul on October 17, 2022, 08:10:37 pm
use SCH 40 1.5" conduit, 45..90 deg sweep at bends.

The gradual curve allows many cables to turn the corner.

jon
Title: Re: cables blocked in corrugated tube
Post by: themadhippy on October 17, 2022, 09:20:09 pm
Quote
use SCH 40 1.5" conduit, 45..90 deg sweep at bends.

The gradual curve allows many cables to turn the corner.
or ,as we do in the uk have a minimum bend radius of 2.5 x the pipe diameter
Title: Re: cables blocked in corrugated tube
Post by: SmallCog on October 18, 2022, 02:24:33 am
I'd use a draw sting to pull some fabric wadding through, try and remove a bunch of the WD40

Use the correct cable lube when you do it again.

If you have trouble you could consider using PoE to power the router rather than having to pull the power cable through.

Around here you're not permitted to run power cables and data cables in the same conduit although standards obviously differ throughout the world

Title: Re: cables blocked in corrugated tube
Post by: coppercone2 on October 18, 2022, 02:36:53 am
klein tool sells a cable pulling gel

I would not worry about residual WD40 in the tube, but you can flush it with alcohol or something if you really need to

Will it really attack cables? I never heard of a small amount of grease deteriorating plastics. If its clear plastic maybe, but I thought it was PVC safe.

ima coil up a piece of PVC wire and leave it in a vial of WD40 and see what happens.
Title: Re: cables blocked in corrugated tube
Post by: floobydust on October 18, 2022, 04:19:39 am
Another issue is that Ethernet cable can get damaged if pulled on hard. Apparently the twists get stretched and ruined which causes problems with data errors.
I've read it shows up on long runs and nobody really notices the errors, just slower data rate and lots of retries but you have to dig for those stats.
Title: Re: cables blocked in corrugated tube
Post by: jonpaul on October 18, 2022, 06:02:45 am
"sweep" is a larg radius bend tube eg 1.5" dia tube with 15" bend rad.

In USA NEC, telco etc you may NOT combine mains power 120/240 in same condut as signal, cable, telco

Check you local electr code, go to an electrical distrub for SCH 40 sweeps

j
Title: Re: cables blocked in corrugated tube
Post by: Terry Bites on October 18, 2022, 06:33:02 pm
Tallow. Mmmmm
Title: Re: cables blocked in corrugated tube
Post by: floobydust on October 18, 2022, 06:53:37 pm
Think of the bugs. It's for the ants and cockroaches to eat lol.  Funny that mice and rats eat car wiring (soy-based insulation) nowadays.
Title: Re: cables blocked in corrugated tube
Post by: mike_mike on October 18, 2022, 06:54:46 pm
I tried using a piece of cloth tied up to the puller wire, and I pulled the piece of cloth from one end to the another end of the tube. Then I changed the cloth and repeated the process 2 more times.
The first time, the piece of cloth was a little wet with wd40, the second and 3rd time was not so wet.
How many days should I wait for the wd40 to evaporate until I can pull again the wires ? This time I will pull only 2 wires the coaxial one and the cat6 network cable.
Title: Re: cables blocked in corrugated tube
Post by: floobydust on October 18, 2022, 06:58:45 pm
You can blast compressed air in the conduit to increase airflow for the stuff to evaporate.
Title: Re: cables blocked in corrugated tube
Post by: Bud on October 18, 2022, 08:43:38 pm
Sorry i am just curious how using WD40 became an idea to pull cables through a conduit... :-//
Title: Re: cables blocked in corrugated tube
Post by: jpanhalt on October 18, 2022, 08:47:41 pm
https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.flickr.com%2Fphotos%2Fdullhunk%2F7214525854&psig=AOvVaw2FWtcCAATwolL2MirVm8BR&ust=1666212421884000&source=images&cd=vfe&ved=0CAgQjRxqFwoTCNisoIzT6voCFQAAAAAdAAAAABAJ (https://www.google.com/url?sa=i&url=https%3A%2F%2Fwww.flickr.com%2Fphotos%2Fdullhunk%2F7214525854&psig=AOvVaw2FWtcCAATwolL2MirVm8BR&ust=1666212421884000&source=images&cd=vfe&ved=0CAgQjRxqFwoTCNisoIzT6voCFQAAAAAdAAAAABAJ)
Title: Re: cables blocked in corrugated tube
Post by: Gyro on October 18, 2022, 09:11:33 pm
You can blast compressed air in the conduit to increase airflow for the stuff to evaporate.

Just don't try using a vacuum cleaner.  ;)
Title: Re: cables blocked in corrugated tube
Post by: Bicurico on October 18, 2022, 09:17:44 pm
The cables are through. Call it a day and live with it. Worst scenario is that you need to replace cables in a few years. By then it will be easier as you just use the existing cables to pull the new ones. These should be excessively wetted in liquid soap as used for manual dish washing. Never had problem with that and it really helps.
Next time you build a house, use a bigger tube!
Title: Re: cables blocked in corrugated tube
Post by: richnormand on October 18, 2022, 09:22:35 pm
You can blast compressed air in the conduit to increase airflow for the stuff to evaporate.

Just don't try using a vacuum cleaner.  ;)

WD-40 fumes can be explosive so vacuum cleaner is a no-no unless in reverse mode (blowing).
If a leaf blower is available I would put it against the conduit for a few minutes. Whatever is left from the wd-40 would be quickly vapourised and diluted.
Just give it a smell test afterwards.

Title: Re: cables blocked in corrugated tube
Post by: TimFox on October 18, 2022, 09:32:27 pm
Sorry i am just curious how using WD40 became an idea to pull cables through a conduit... :-//

I remember an episode of the American animated comedy "King of the Hill" where Mr Hill had difficulty using the wrong key to open a lock.
He tried to open his spray can of WD-40, but it was stuck, so he pulled out his pocket bottle of WD-40 to unstick the lid on the big can before spraying the key.

There is a theory that any mechanical problem can be solved with a Vise-GripsTM pliers, a hammer, duct tape, and WD-40.
Title: Re: cables blocked in corrugated tube
Post by: jpanhalt on October 18, 2022, 09:46:49 pm
And, "if a hammer doesn't work, you need a bigger hammer."  Said a carpenter friend of mine.
Title: Re: cables blocked in corrugated tube
Post by: Ed.Kloonk on October 18, 2022, 09:54:36 pm
Sometimes, in the past, I've had to pull things through buried regular standard conduit both straight and corrugated combined with various types of sweeping bends. What can happen is the person who places the pipe can be heavy handed with the pipe glue and a big bubble of glue lays inside the pipe near a joint.

When you come along later to rod the pipe, you awaken the skinned glue and then smear it along the inside of the pipe and on whatever is being poked through. Not nice.
Title: Re: cables blocked in corrugated tube
Post by: Gyro on October 18, 2022, 10:06:44 pm
You can blast compressed air in the conduit to increase airflow for the stuff to evaporate.

Just don't try using a vacuum cleaner.  ;)

WD-40 fumes can be explosive so vacuum cleaner is a no-no unless in reverse mode (blowing).
If a leaf blower is available I would put it against the conduit for a few minutes. Whatever is left from the wd-40 would be quickly vapourised and diluted.
Just give it a smell test afterwards.

This forum definitely needs an international humour emoji.
Title: Re: cables blocked in corrugated tube
Post by: Messtechniker on October 18, 2022, 10:11:17 pm
My experience with cable conduits:
they are never big enough. :horse:
Even when planned by professionals.
See for example, the new Berlin Brandenburg
airport (BER) amongy many others. :palm:
Title: Re: cables blocked in corrugated tube
Post by: TimFox on October 18, 2022, 10:18:13 pm
My experience with conduits embedded in concrete floors for radiation cells is that the builders are perfectly capable to fill the conduit pipes with concrete before we had a chance to pull cables.
Title: Re: cables blocked in corrugated tube
Post by: Ed.Kloonk on October 18, 2022, 10:25:11 pm
My experience with conduits embedded in concrete floors for radiation cells is that the builders are perfectly capable to fill the conduit pipes with concrete before we had a chance to pull cables.

You put on temporary risers, you tape it all up and secure it back.

"There's no way they'll get concrete in that.."

 >:(
Title: Re: cables blocked in corrugated tube
Post by: TimFox on October 18, 2022, 11:53:35 pm
My experience with conduits embedded in concrete floors for radiation cells is that the builders are perfectly capable to fill the conduit pipes with concrete before we had a chance to pull cables.

You put on temporary risers, you tape it all up and secure it back.

"There's no way they'll get concrete in that.."

 >:(

Fools are infinitely ingenious.
Title: Re: cables blocked in corrugated tube
Post by: Ed.Kloonk on October 19, 2022, 02:35:21 am
My experience with conduits embedded in concrete floors for radiation cells is that the builders are perfectly capable to fill the conduit pipes with concrete before we had a chance to pull cables.

You put on temporary risers, you tape it all up and secure it back.

"There's no way they'll get concrete in that.."

 >:(

Fools are infinitely ingenious.

One concreter I knew, with that hose, I've wondered if he thought he was putting out fire with it.

Back when video pipe inspection was still fairly new and cumbersome, I got asked by a home owner to hire and supervise a pipe inspection of a failed ducted vacuum system installation.

These are 2" pipes and sure enough somewhere under the floor the pipe was 1" off-center at a join and there was concrete in the pipe. The ducted vacuum company had sub-contracted the placement of the ducting during construction stage so that the company boss could just come in, prance around, finish off the outlets and hang the machine itself. Very lazy.

Long story short, when we tracked down the fitter fellow, he said "who the Hell uses primer on joints anyway?" Up in the roof we found a joint we could easily get to, wrenched both ends and sure enough, fell apart. When they poured the concrete, the pipe in the ground didn't stand a chance.
Title: Re: cables blocked in corrugated tube
Post by: CatalinaWOW on October 19, 2022, 03:00:08 am
I have seen evidence of insulation degradation by oils/greases on very old equipment that got generously lubed at some point in its life.  The type of degradation varies with the materials involved and includes softening and swelling, getting hard and brittle and simple discoloration.  But this is in gear that has been aging for several decades.  And in spite of the visual evidence of degradation the equipment was still working fine.  I strongly suspect that you won't see any issues in your application before the cable becomes so obsolete that it is abandoned or replaced.
Title: Re: cables blocked in corrugated tube
Post by: coppercone2 on October 19, 2022, 05:07:31 am
yeah but that applies thick, how thin is a layer of WD40 ? That stuff trickled down and left a very thin film. I think you would need a strong contact layer.. its like water

Even 3-in-1 oil is alot thicker then WD40 and thats way too thin for machinery applications