amored with no outer plastic.......

[spidersparks]

Hi guys, I'm starting a job next week on a school built in the mid to late 60's, all their sub mains are running underground in tunnels, what's confused me is that these sub mains are amoreds but for some reason they have no outer plastic sheathing.... Never seen this before and one of them is due to be extended and I'm not sure how to go about this any help greatly appreciated
David

 

[trev]

New un on me mate. someone will have an answer for you.
Extending them will surely be just a case of glanding them into a metal box to maintain armouring earth continuity.

 

[telectrix]

as trev said. never come across it myself, but understand it used to be used in the third world, south of birmingham.

 

[Guitarist]

If it's in Suffolk then it's understandable...

 

[spidersparks]

Ha ha cheers

 

[itselectric]

Is the armour as you would find in an swa. Or is it braided

 

[Guest55]

i've seen plenty lead paper cable that has a bare swa outer layer , often used for indoor only submains supplies , in large old buildings.

im sure tony will give us the lowdown if he turns up , but i reckon its pilc.

 

[Guest55]

as for jointing it.........
best leave it to an old hand.
;-)

 

[Darkwood]

Get a pic up if possible never miss an opportunity to share..... )

 

[Lucien Nunes]

plenty lead paper cable that has a bare swa outer layer , often used for indoor only submains supplies

My thoughts exactly. Spidersparks does it look like this? - paper insulated lead covered (PILC) - Resin joint needed.

never miss an opportunity to share

Naked PILCSWA feast for you...

 

[spidersparks]

Lucine Nunes that's exactly what it is thanks very much for the pictures I have one on my phone and on the forum app can't work out how to get it on here but your pictures are very similar

 

[jay sean]

Ive seen some swa cables but without the pvc outer sheath, I have seen it at some 1960s-1970s 400kv/275kv substations, used for submains supplies.

 

[Engineer54]

Yes these cables are PILC cables. As far as i know these old PILC cable were never produced with PVC over sheaths, it was always a impregnated cloth type material, damned if i can remember the correct term for it!! lol!!

A similar type cable is ''waveform'', an armoured cable, that the DNO's use or used for LV local distribution network cables...


OP be warned, these PILC cables are not going to be easy to extend, especially if you don't have a pretty good jointing experience in your background. These are the cables that used to have be, lead wiped at joints and terminations!!

Tony's your man there, for jointing experience!!

 

[snowhead]

HEAT SHRINK CABLE JOINTS, PILC SWA CABLE JOINTS, BS6480, PAPER LEAD SHEATHED CABLE JOINTS 3.3KV

 

[Engineer54]

HEAT SHRINK CABLE JOINTS, PILC SWA CABLE JOINTS, BS6480, PAPER LEAD SHEATHED CABLE JOINTS 3.3KV

All looks very easy doesn't it, now go off and try and make that joint off!! ...lol!! There are all sorts of jointing/termination kit's now for PILC cables, like resin fill, heat shrink, cold shrink and even still, lead wipe.

The first thing i'd like to see, is an inexperienced person splitting and removing the lead sheath to expose the conductors. Not as easy as it first looks, i can assure you!!

I was just looking through some of the components that make up these heat shrink joint kit's you linked too. I was expecting to see heat shrink tubing to cover the individual Paper Insulated cores, (...you don't want that oil impregnated paper drying out) but didn't see any core tubing!!!

 

[Knobhead]

I’ve never seen PILCSWA without an outer sheath.

Just watched the video clip of removing the lead sheath. No way would I do it like that, too much of a chance of damage to the cores. Done the correct way the lead comes off easily and quickly with no chance of damage.


E54, depending on the age of the cable, the early ones were covered with tarred jute. Later tarred hessian and now PVC. Even the new PVC sheathed will have a bedding layer of tarred hessian, lovely stuff to get off.

 

[Des 56]

I’ve never seen PILCSWA without an outer sheath.

Just watched the video clip of removing the lead sheath. No way would I do it like that, too much of a chance of damage to the cores. Done the correct way the lead comes off easily and quickly with no chance of damage.


E54, depending on the age of the cable, the early ones were covered with tarred jute. Later tarred hessian and now PVC. Even the new PVC sheathed will have a bedding layer of tarred hessian, lovely stuff to get off.

Cleaning the armourings with a parrifin soaked rag is a job seldom practiced now I suspect


I have memory of being apprentice in the pit and having to help lay/install one in the middle of winter
It took the whole of the electrical department to straighten the coiled cable.I believe they were double wired armourings

The frost had got to it,the coils would just be upright with half a dozen sparks hanging on to bend it back down,
I suppose they are much more prone to frost damage without a sheath,buy they certainly existed in the mines

 

[Engineer54]

I’ve never seen PILCSWA without an outer sheath.

Just watched the video clip of removing the lead sheath. No way would I do it like that, too much of a chance of damage to the cores. Done the correct way the lead comes off easily and quickly with no chance of damage.


E54, depending on the age of the cable, the early ones were covered with tarred jute. Later tarred hessian and now PVC. Even the new PVC sheathed will have a bedding layer of tarred hessian, lovely stuff to get off.

Only ever seen the older covered PILC/SWA cables then, i can't say i've ever seen them with a PVC outer sheath, only that impregnated/tarred hessian. lol!! I know removing the lead sheath can be a real hassle if you don't know what you're doing. Only ever help make off a couple of PILC/SWA joints and one or two terminations. They were all wiped joints and terminations, that i took no part in, so i'm no expert with PILC cables. In fact i've never used them since, removed plenty of them though!! lol!!

 

[Lucien Nunes]

Just watched the video clip of removing the lead sheath. No way would I do it like that

Other side of the pond though, it's all different over there. Might have wirenuts in that joint...

 

[davethsparky]

Doubt it, wire nuts are a merkin thing and I think that video is from New Zealand.

Out of interest what is the correct way to strip it?
I've watched the man from the dno do it a couple of times and he used an insulated tool with a tiny blade at the end which he jest tapped along the length to split it.

 

[Des 56]

I think the correct winding of the oil impregnated paper, how its wound to prevent unravelling
after it has been jointed, will need more attention than how the lead sheath is removed
I don't think hot fill compund will affect the paper either

 

[Engineer54]

When you watch a skilled jointer at work, it all looks very easy, it's not!! But many ''Think'', i can do that, but rarely if ever Can!! lol!!

 

[Lucien Nunes]

that video is from New Zealand

Ah yes, I stand corrected thought it was from the US

 

[Engineer54]

I think the correct winding of the oil impregnated paper, how its wound to prevent unravelling
after it has been jointed, will need more attention than how the lead sheath is removed
I don't think hot fill compund will affect the paper either

That is what was always used to seal PILC cable ends and the paper insulation.

 

[Des 56]

When you watch a skilled jointer at work, it all looks very easy, it's not!! But many ''Think'', i can do that, but rarely if ever Can!! lol!!

It was part and parcel of an apprenticship for many sparks in the state run heavy industries.ie to make off these type of joints and couplers

You were also tested and graded on your performance

A cable jointer will make it look very easy,yes,however,trainee sparks in these industries got the degree of difficulty made very well aware to them by having to do practice these joints techniques

I for one would admit that cable jointing is one fascinating skill to watch and admire,their skill will surely never get completed diluted like our own has unfortunately

 

[Engineer54]

It was part and parcel of an apprenticship for many sparks in the state run heavy industries.ie to make off these type of joints and couplers

You were also tested and graded on your performance

A cable jointer will make it look very easy,yes,however,trainee sparks in these industries got the degree of difficulty made very well aware to them by having to do practice these joints techniques

I for one would admit that cable jointing is one fascinating skill to watch and admire,their skill will surely never get completed diluted like our own has unfortunately

I bet they don't let them practice too much on modern day joints etc, the typical cost of a 3 core 11KV cable heat shrink joint, is or was the last time i looked, around the 300 to 400 quid mark!! lol!!

 

[Knobhead]

Only ever seen the older covered PILC/SWA cables then, i can't say i've ever seen them with a PVC outer sheath, only that impregnated/tarred hessian. lol!! I know removing the lead sheath can be a real hassle if you don't know what you're doing. Only ever help make off a couple of PILC/SWA joints and one or two terminations. They were all wiped joints and terminations, that i took no part in, so i'm no expert with PILC cables. In fact i've never used them since, removed plenty of them though!! lol!!

One of mine:

 

[Knobhead]

I bet they don't let them practice too much on modern day joints etc, the typical cost of a 3 core 11KV cable heat shrink joint, is or was the last time i looked, around the 300 to 400 quid mark!! lol!!

Just have a look for the price of a cast iron, lead sleave (BICC) 11KV joint. It will make you're eyes water!

 

[Knobhead]

Out of interest what is the correct way to strip it?
I've watched the man from the dno do it a couple of times and he used an insulated tool with a tiny blade at the end which he jest tapped along the length to split it.

I was taught both at work as an apprentice and later by the EMEB the easiest, quickest method.

With a (Stanley) knife score around where you want the lead to terminate. From that circular score make two parallel “tram tracks” about ½“ apart to the cut end of the cable. At the cut end open up the two score lines with a heavy hack knife and a hammer. This will give you a tag that you can get you’re pliers on. Peal it back just like opening a can of corned beef. Once the strip is removed the lead sheath is just pealed off. Doing it this way the lead termination is slightly belled out thereby preventing a sharp edge against the cores.

The belting papers just after the lead should be bound for ½“ from the termination. The belting papers are then unwound to the binding and torn off. I’ve always use waxed string whipping to terminate the belting. (I’m old fashioned)

 

[Engineer54]

Just have a look for the price of a cast iron, lead sleave (BICC) 11KV joint. It will make you're eyes water!

Think i should have said ''Termination kit'' not a joint!! lol!! Joints are obviously much more expensive,,,

 

[ipf]

I was taught both at work as an apprentice and later by the EMEB the easiest, quickest method.

With a (Stanley) knife score around where you want the lead to terminate. From that circular score make two parallel “tram tracks” about ½“ apart to the cut end of the cable. At the cut end open up the two score lines with a heavy hack knife and a hammer. This will give you a tag that you can get you’re pliers on. Peal it back just like opening a can of corned beef. Once the strip is removed the lead sheath is just pealed off. Doing it this way the lead termination is slightly belled out thereby preventing a sharp edge against the cores.

The belting papers just after the lead should be bound for ½“ from the termination. The belting papers are then unwound to the binding and torn off. I’ve always use waxed string whipping to terminate the belting. (I’m old fashioned)

Must be 30 years since I last did a termination. Doing maintenance, repairs and alterations in glass fibre production plants during summer shutdowns. Early on, I was taught to strip the lead like that, we had a special chisel/knife, then peeled it inch by inch. It was the term wiping I got really good at. I was the kid given plenty of time to practise, while the others were running around like madmen, 'till brew time that is, then I was the one running about. Got sick to death of showing the finished article only to be told to get the blow torch out, strip it down and do it again proper. It was bloody perfect IMO, probably was too. Oh, for the days of the true apprenticeship.

 

[Knobhead]

The wiped lead joint can look granular if too much heat is used. The tin separates from the lead.
I was shown “plastic wiping” at the EMEB collage. You have to trust you’re mate, he has charge of a metal pot with “type D” plumbing metal in it. Using a soup spoon he would pour the metal on to the moleskin in your hand (gloves, don’t be silly). Then you could build up the plumb quickly and not overheat the cable papers by too much use of the torch. The other advantage with this method was I could add tinmans solder to the pot increase the tin content.
You couldn’t do that with a stick wipe.

I did about 40 185mm² terminations on one job using CMP lead lined glands. Brilliant things, wrap the base of the gland with asbestos string to seal it and just heat it up. The lead would melt and that was it, job done. I had a look for them for RoB, not made now.

I don’t miss mauling bloody great big cables about though. Rerouting a 50 year old 0.3”² was a swine of a job. I had to warm the cable with a space heater to stop the tarred hessian cracking and dropping off. Everyone got covered in tar. When I cut the cable back the papers were as good as new. The only time I’ve made off a cable and lowered the switchboard on to it afterwards.

 

[Fin170]

Currently stripping out thousands of miles of the stuff and although I have an appreciation for most flavours of old gear....those cable are not high on the list :lol: Kudos to the lads that pulled them in and terminated (for once I'd say the joints to the armour were not as good as quality as modern equivalents) them. I'd imagine the 240mm equivalents I've recently chopped (in sub meter lengths due to weight) were a pig to work with, every time you cut them the armour blows out followed by 60 years of dust and other unspecified crap filling the air

Also the large single core bitumen(?) wrapped cables have melted over time making them a pain to separate and cut