Pulling 16mm SWA through 150 M of conduit?

[1Justin]

Edited- I was talking nonsense but can't delete this message. Blah Blah.
Mine is black no sugar. Ta...

 

[HandySparks]

Since the cable will be down there in 100% humidity anyhow, maybe not a practical problem...

OK, since water's been mentioned, if the ducting is lying at low level or the ends are upturned and not capped, there's a fair chance of some water in the duct. This leads me to ask whether anyone's tried deliberately filing a duct with water before pulling a cable through. It would provide some lubrication (although not as good as a proper lubricant) and, maybe more importantly, it would reduce the effective weight of the cable. Any thoughts?

 

[telectrix]

OK, since water's been mentioned, if the ducting is lying at low level or the ends are upturned and not capped, there's a fair chance of some water in the duct. This leads me to ask whether anyone's tried deliberately filing a duct with water before pulling a cable through. It would provide some lubrication (although not as good as a proper lubricant) and, maybe more importantly, it would reduce the effective weight of the cable. Any thoughts?

sounds a bit wet to me.

 

[Guest55]

not read the whole thread , understandably at 5 pages long , but i'd want an access point left dug open every 20-30 mtrs.
trying 150mts in a single pull would be insane.

 

[High Tower]

If a couple of labours can get enough purchase on a bit of rope to stretch that piece of armoured I will eat my hat !!! I am not talking about yanking the hell out of it , and assume a modicum of sense is being applied to the pull and the cable is correctly secured , having said that .

Unroll 150m of 16mm 3 core on a carpark, get hold of one end and pull like hell, feel the give and back lash in the cable, that's with only one person try then a couple. It's easily possible to destroy the cable in this situation.

 

[chronyx]

I'm in Surrey too, on the basis that you try and pull the SWA through can I come and watch?

Me too

 

[JD6400]

Unroll 150m of 16mm 3 core on a carpark, get hold of one end and pull like hell, feel the give and back lash in the cable, that's with only one person try then a couple. It's easily possible to destroy the cable in this situation.

I must be getting cable from a different source to others then because I can honestly say that I have never seen a cable of that size " give " apart from when it is on the end of digger while being ripped out again for salvage ?

 

[JD6400]

Don't get me wrong , I agree it is easy enough to stretch the sheath on even the largest of cables , but I just can not see how a couple of men sensibly pulling with the correct gear , can ever manage it .

 

[HandySparks]

Me too

Looks like we might have a (cable) pulling party? :smile5:

 

[chronyx]

Looks like we might have a (cable) pulling party? :smile5:

Well this week's work has fallen through so far so yeah why not, always up for a bit of grunt work

 

[GLENNSPARK]

Looks like we might have a (cable) pulling party? :smile5:

that sounds like p0rnography...

 

[chronyx]

that sounds like p0rnography...

Changed my mind

 

[1Justin]

Not wanting to disappoint anyone looking for sporting action, but I think I've made up my mind to advise a no-go without more digging. The gardener (who is the primary recipient of this cable in his shed at the end..) won't get his kettle, - or at least not very soon.

Thanks for the inputs.

 

[chronyx]

Can't you just cleat it along the bottom of a fence? This is important you never said there was tea involved

 

[Silly Sausage]

I've just checked out how far 150m actually is...that is one frigging big garden!
If they can afford to live in a place like that, they can afford to pay for a few holes to be dug, don't make life hard for yourself for these rich basterds.

I can imagine you having friction trouble dragging it round that bend.

 

[Beavstro]

Ah come on Justin! I think this is nearly at the stage where the forum members will pay for the work just to see the out come of this situation! Lol

 

[chronyx]

I can imagine you having friction trouble dragging it round that bend.

And we're back to Glennsparks ****ography I blame your avatar

 

[Engineer54]

If a couple of labours can get enough purchase on a bit of rope to stretch that piece of armoured I will eat my hat !!! I am not talking about yanking the hell out of it , and assume a modicum of sense is being applied to the pull and the cable is correctly secured , having said that .

Going by that sort of statement, i dread to think of the state of some of the cables that have been pulled through small long ducts in the UK!! Going round even slow bends in a long ducted system and you'll be having to yank that cable when dead pulling, especially in a small 50 mm corrugated duct over 150 metres. ...But hey, what the hell do i know, ..Right??

 

[7029 dave]

That is some pull with a small duct, good luck!!Bet you will be digging down on it.

 

[iamelectric]

i dont get y some people think a 50mm duct is to small for a 16mm swa , a 16mm swa is roughly 30-32mm in diameter!!!

 

[Guest55]

of course the O.P. has confirmed that 16mm cable is sufficient for his lighting max volt drop over 150mtrs ..................

?

;-)

 

[44ALLAN]

I still think filling the ducting with water was the best idea :rolleyes4::confused5:.
Hopefully the sheath isn't damaged mind

 

[Dipzy]

Load assuming 4Kw max
Cable 16mm 3 core swa
Length 150m
VD 6.3v (2.7%)
Load 17.4 A


Tin Hat frimly on

 

[iamelectric]

i was assuming it was 4 core for 3 phase , so it wont even be 30mm

 

[Engineer54]

I still think filling the ducting with water was the best idea :rolleyes4::confused5:.
Hopefully the sheath isn't damaged mind

Now come on, are you actually being serious?? lol!!

 

[44ALLAN]

Now come on, are you actually being serious?? lol!!

hahahahaha....................read the last line again:frown2:

 

[Engineer54]

hahahahaha....................read the last line again:frown2:

You're laughing but i'm pretty sure some daft bugger will remember your post and fill a duct with water!! lol!!
Let's hope the water isn't on a meter, and has devised some sort of method of draining it all out. ...lol!!

 

[44ALLAN]

You're laughing but i'm pretty sure some daft bugger will remember your post and fill a duct with water!! lol!!
Let's hope the water isn't on a meter, and has devised some sort of method of draining it all out. ...lol!!

To be fair I did put 2 stupid faces after the comment lol.

 

[CSEE]

Use a cable sock, together with a cable pulling machine hired from HSS or Speedy along with the correct cord for cable pulling not polycord and it will go through slowly but surely

 

[1Justin]

Hi CSEE.Thanks, you mean something like this Cable Pulling Winch - Tool Hire, Equipment Hire, Lifting Hire, Plumbing & Pipe Hire - Brandon Tool Hire ? That looks plausible maybe. What sort of rope do you mean? - I assume something non stretch (Dyneema/Kevlar) would be the only sensible option.

 

[Dave 85]

Me and my old boss tried something similar years ago. Same ducting and cable size. Duct about 80metres long with a slight dogleg at one end. We had to tie the rope to the back of my van as pulling it by hand was impossible. Managed to get it 80% of the way but the rope snapped when the SWA reached the dogleg. we dug a hole found the break and managed to finish the job but to be honest I'd never wanna do it again.

Just let the customer be aware that it might not be possible.

 

[Billythekid]

You're laughing but i'm pretty sure some daft bugger will remember your post and fill a duct with water!! lol!!
Let's hope the water isn't on a meter, and has devised some sort of method of draining it all out. ...lol!!

I can actually picture someone at the ends dipping tissue in to soak it out lol

 

[DPG]

Me and my old boss tried something similar years ago. Same ducting and cable size. Duct about 80metres long with a slight dogleg at one end. We had to tie the rope to the back of my van as pulling it by hand was impossible. Managed to get it 80% of the way but the rope snapped when the SWA reached the dogleg. we dug a hole found the break and managed to finish the job but to be honest I'd never wanna do it again.

Just let the customer be aware that it might not be possible.

E54 ain't gonna be pleased with your van antics :lol: Daz

 

[Billythekid]

OP, There is some sound advice in amongst the absurdities, I would also recommend a Mandrel to test that the ducting is still "true". Running a mandrel of a slightly smaller size than interior of duct will save you a lot of heartache.

Regards

Billy

 

[Engineer54]

E54 ain't gonna be pleased with your van antics :lol: Daz

You're right there!! lol!! That cable will have been stretched to buggery, ...and No If's Or But's about it!! lol!!

 

[Victor]

I had a job a few years ago to pull 70m through a 50mm underground conduit. Have to say NEVER AGAIN will I take on that kind of job as even the slightest rise or kink on the conduit can result in the cable sticking, in the end it was a case of digging several holes and and two days locating the conduit before being able to get the new cable plus being out of pocket on the job.

 

[1Justin]

"Never again". - That's a recurring theme! I was just talking to the hire company about their winch, and they don't really know how to use it. For instance 10mm polypropylene (~ 1 tonne break, but very stretchy, maybe need to go bigger) or spend an arm and a leg on dyneema rope (winch manufacturers say use non-stretch rope).

 

[Dave 85]

E54 ain't gonna be pleased with your van antics :lol: Daz

I expect not! Fortunately for me, I care very little for his archaic opinions.

 

[Engineer54]

I expect not! Fortunately for me, I care very little for his archaic opinions.

And unfortunately, why you will continue to stretch cables, by not knowing what the hell you're doing!!

 

[SJD]

"Never again". - That's a recurring theme! I was just talking to the hire company about their winch, and they don't really know how to use it. For instance 10mm polypropylene (~ 1 tonne break, but very stretchy, maybe need to go bigger) or spend an arm and a leg on dyneema rope (winch manufacturers say use non-stretch rope).

While I don't know much about pulling very long cables (and I'm going to be very wary if anyone ever asks me to now), why does it matter if the rope is stretchy? Could it be good to have some stretch in it, to reduce the mechanical shocks to the cable? Perhaps E54 or someone can advise.

 

[terminator]

Because you can't 'feel' when you're actually pulling the cable when it gets tight, plus all your energy is absorbed by the stretchy rope and not into moving the cable.

 

[Engineer54]

While I don't know much about pulling very long cables (and I'm going to be very wary if anyone ever asks me to now), why does it matter if the rope is stretchy? Could it be good to have some stretch in it, to reduce the mechanical shocks to the cable? Perhaps E54 or someone can advise.

Apart from what Terminator has just stated, winches work on the basis of having an adjustable clutch which is set to slip/freewheel at a predetermined torque point, applicable to manufacturers recommendations for a given size and make-up of cable. All the cable winches i've experience of, use steel draw cables (and cable socks), though i have seen some using reinforced rope draws....

The other fact is that you shouldn't even attempt pulling cables into a continuous duct, over very long distances in one go, but then that's another matter altogether.

The point is, if carrying out a cable pull correctly, and the cable winch is continuously going into slip mode, then the pull length and or design of the cable duct is Wrong, and when those that know no better hook the cable pull wire up to a van//lorry/tractor and forcibly drag the cable come what may, through!!