- This video continues on a series of video
on how stuff is being made.
And I'm down at Doncaster Cables with Aaron,
to look at fire performance cables.
Can you tell me a little bit about them?
- [Aaron] Yes, our brad of fire performance cable
is called, Firesure.
We do a standard and an enhanced version of the cable.
And the way we manufacture the cable is quite unique.
So we've gone with a unique construction and design
and it brings lots of features and benefits
for the end user and the installer.
So impact resistance wise,
ours is a lot more impact resistant
because we're filling all
of the air gaps in the cable with sheathing compound.
So if you were to accidentally drop something on the cable
or stand on it, then you have less of an indentation,
less risk of damaging the cores.
Also, that means that it's
less kinkable or more resistant to kinks.
So as you're pulling the cable through a tray work,
if it was to kink over, our cable would go back
to its original shape and again, protect the cores.
And then your favorite from today,
is the smoke transmission.
So we can demonstrate smoke transmission,
where a competitor's cable could act like a conduit
and smoke be drawn into another room.
Whereas ours because it's filled,
we've got no smoke transmission in the cable.
- I think it means, now we're gonna have to step into
Doncaster Cables to see how this cable is being made.
However, you did promise me, at the end,
what am I gonna get a chance to see?
- We're gonna set fire to some of the Firesure cable
and see high performance testing.
We've already recorded a video of this,
which was the twin and CPC video.
And we went into quite a lotta detail about
how this machine works.
But this is still the same process
for the fire performance cables.
Once the wires are drawn,
they're then fed into the back of the extrusion machine.
So here you can see we're flying off the copper wire
and then that will come through
around some tension wheels and some pullers.
So we can keep the wire at the right tension
before it feeds into the extrusion head.
At this stage we'll see one of the main differences
to the twin and CPC that we made in the other video.
The extruders on the twin and CPC line are processing
a thermoplastic PVC and we're melting down granules,
so, like, they become a molten PVC
and we can form it around the copper.
And in this extrusion line, it's the reverse.
So we've got a cold silicon,
which we're passing down the extruder barrel
and it's all chilled.
And then we have to cure the silicone afterwards,
to then form its shape.
In traditional thermoplastic extrusion,
we'd be going into a cold water trough now,
to cool the product.
Because this is the opposite,
we actually use heat to cure the silicon.
So this initial oven is a high temperature
thermal shock oven.
About 500 to 600 degrees Celsius.
And after this oven,
there's then a long array of other ovens,
three in our case,
where the silicon is continued to be warmed at
300 degrees Celsius, as it travels down the whole line.
The length of this extruder is around about 50 meters.
But the cables actually come back
through the extruder multiple times,
so it extends the length of the line to about 150 meters,
which allows us to give a slow curing process
for the silicon.
After the ovens, there's quite a lot of processes
happen in quick succession.
So we have a laser meter counter,
so we can record the length of the cable.
Then a high voltage spark tester,
which is continuously testing
that there's no pin prick defects in the insulation
or any insulation faults.
And then we have a chalking unit
to apply a layer of chalk, to aid in stripability.
And then finally, it's onto the take up drum.
This machine typically running between 200 meters a minute
and 300 meters a minute.
And we're making bulk lengths matched up
for the next process, which will be laying up.
We've now got the cores,
so in this instance we're making a 2 Core in CPC.
So we've got a blue and a brown conductor
and then a bare earth wire being fed up out of the box.
The bare earth wire that we're using
is a tinned copper circuit protective conductor.
These cores are then twisted together.
All the twist is coming from inside of the machine,
which is the bow inside the machine.
But you'll see the twist traveling out the machine
and up towards the conductors.
As the conductors come through,
we'll go through a high voltage spark tester again,
to further test that there's no defects in the insulation.
And then we add a tape around the cores,
again, to aid in stripability.
We're feeding the CPC.
And then the next part is adding the metallic tape,
which is a key part of the fire barrier.
The whole package of the fire performance cable makes
up its characteristics and performance
but the aluminum tape is a critical part.
We're adding the aluminum tape
and we're adding it in helically.
So the tape is wrapped around and round the cores
with a a large overlap.
And this gives us a lot of protection.
Makes the cable robust so it can be bent easily.
It can be dressed without fear of deforming the cable.
Our Firesure 500 is quite different
to most of the cables in the market.
Most of the cables will have a longitudinal tape
which is fed in at the extrusion stage.
And we choose to do this, although it's a slower process,
we're adding more of an overlap over the tape.
We're getting better continuity with the CPC.
And then we're getting better data transmission
because we're twisting the cores together
and adding the tape at the twisting stage.
So although it's a longer process and an additional process,
it gives us lots more feature and benefits in the cable.
Inside the take up build of the strander,
the drum is rotating,
which is pulling the cores and the tape onto the drum.
And it's the bow that's spinning around the drum,
that puts the twist into the cores and the tape.
So the cores and the tape come into the bow,
travel all the way around it,
through a tensioning wheel and then back onto the drum.
Looking at the cable makeup so far,
we've got an aluminum metallic tape,
which is providing one of the fire barriers.
We then add the circuit protective conductor.
We have the inner easy tear tape.
And then the two cores, blue and brown.
We now need to sheath this with the outer sheathing,
which is then the final part of the fire barrier.
To do this, we come into the extrusion line,
we're paying off the drum
and then we're melting down thermoplastic, low smoke,
non-halogen material around the tape.
Our tape is specially developed.
It includes a copolymer.
So as the sheathing comes through
and processes onto the tape,
the tape adheres to the sheath,
so that when you strip back the sheathing,
you can then remove the tape at the same time.
And with the sheathing, we're actually pressure extruding
the sheathing around the tape and around the cores.
So there's no air gaps left inside the cable.
There's no chance of smoke transmission
along the cable in a fire situation.
It also makes it more robust, more durable,
more resistance to kinking and makes it easier to install.
The cable is now red hot,
as it comes from the extruder head, so 180 degrees Celsius.
And we need to cool that down.
So we'll go through the water baths,
where we're applying cold water to cool the product.
It'll then go through an air wipe system to wipe that water
off before we go and high voltage test the cable yet again,
just to check that there's no electrical defects
in the outer sheath into the tape.
After this process, it's onto the final take up drum,
where we can wind bulk lengths
before we wind them into 50s, 100s,
250s or 500 meter reels.
This is an example of an automated winding machine.
And on this occasion, winding into 100 meter reels.
And this is actually going to
overseas export markets in Dubai.
We have lots of different approvals
on the Firesure500 products.
So we have basic approval.
And also LPCB,
which stands for Loss Prevention Certification Board.
And these approvals mean that there's a third party
verifying that the cable is fit for purpose
and complies with the regulations.
Fire performance cable has some stringent regulations,
in particular with fire testing
and different types of fire testing.
And we can show you some examples
of the types of fire tests that we do on the product.
There's a wide variety of fire performance testing
that can be conducted on a fire performance cable.
These range from resistance to fire alone,
to resistance to water, resistance to impact
and then you get standard and enhanced versions of the test.
There's some confusion in the marketplace
with regards to PH 120 and PH 60.
And with regard to emergency lighting
and where they can be used.
The PH is the duration of the test.
So 120 means that it lasts 120 minutes, PH 120.
This doesn't necessarily mean that it's an enhanced cable,
as you can pass five performance tests at PH 120
and still be a standard fire performance cable.
So it's important to make sure that you're using
the correct specification fire performance cable
for the correct installations.
The example that we're showing, is a fire performance test,
which is, resistance to fire impacts and water,
all during the same test.
The whole of this test will last 30 minutes.
The first 15 minutes will be resistance to fire and shock.
And every five minutes there'll be an impact on the cable.
And this is replicating things falling down
in the event of a fire hitting girders, causing vibrations.
And then for the second 15 minutes of the test,
it'll be resistance to fire impact and water.
So a water spray comes on,
the impact still continue every five minutes
and this is to replicate the sprinklers turning on
in a building.
Throughout the test, the fire performance cable
needs to maintain circuit integrity
for the test to be compliant.
We're proud to manufacture our Firesure cables
in the UK.
And we feel they bring lots of features and benefits
to the installer.
If you want to check out how we manufacture twin
and CPC cable, click the video on the screen.