Copper-Clad Aluminum as an alternative to
Copper flexible conductors for electric
power cables:
opportunities and challenges
presented by Franco Peruzzotti
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Jicable’15, 21 - 25 June 2015 - Versailles - France
19 June 2015 3,4
Copper vs Aluminum, historical trend price
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Copper price pressure, consequences
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Base Metals Total Prysmian Volume 2014
Copper
476 ktons/year
Aluminium
155 ktons/year
Lead
23 ktons/year
TOTAL
654 ktons/year
Total base metals by region
in ktons (act.2014)
SA
62
NA
85
APAC
70
EMEA
423
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Rod 383 ktons/year
Rod 148 ktons/year
Cu/Al usage ratio Prysmian applications, 2014
HV&Submarine
Power Distribution
Infrastructure
Renewable Energy
Special&OEM
Oil&Gas
Trade&Installer
Heavy Industry
Transportation
Automotive
Aerospace
Elevator
Military&Defence
Telecom Solution
Multimedia
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Conductors, properties comparison
key features
quality
conductivity IACS
Specific Gravity, kg/dm3
weight per km, R equivalent
diameter, R equivalent
mechanical, Tensile kg/mm2-hard
mechanical, Tensile kg/mm2-soft
Elongation, %
fine wire drawing
fine wire flexibility
installation handling
moisture resistant
connectors/terminations
ease of recovery (end-of-life/or earlier for theft)
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Copper Aluminum CCA-10%
ETP
1350
Copperlite™
100
8,91
1
1
45
35
25
***
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Jicable’15, 21 - 25 June 2015 - Versailles - France
61
2,71
0,6
1,28
27
17
15
*
*
**
*
***
63
3,32
0,6
1,26
30
17
15
***
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**
*
Copper-Clad-Aluminum, a possible solution to replace Copper
Copper-clad aluminum (CCA) conductors:
• A core of aluminum clad in a
concentric layer of copper
• Copper by volume, 10% or 15%
• Conductivity 63% - 67% IACS
• Processed with conventional copper drawing lines
• Skin effect, suitable for high-frequency applications
• Lightweight
• Approximately 40% lighter than Cu at same DC Resistivity
• Cost saving
• Lower in cost vs Cu with comparable performance
• Anti-theft
• Cladding forms a permanent metallurgical bond, making separation
practically impossible
• Fully recyclable
• CCA can be recovered, i.e. as a particular aluminum alloy, to solve the
issue of industrial scrap, as well as end-of-life product management
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Copperlite™ CCA process
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Cladding vs plating technology
Plating: electrochemical process
• Cu thickness limitation and diameter
– the higher the diameter the lower
the output,
• Cu layer has weak consistency due to
high porosity structure, difficult
drawing,
Cladding: metallurgical process
• Copper being applied is solid, compact
tape, so theoretically no limitation to
Cu thickness,
• Strong Cu/Al metallurgical bond
allows easy drawing,
• Environmentally friendly
• High environmental impact
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Telecom aerial Copper cable
To counter theft, a new twisted-pair aerial TLC cable
made from Copperlite™ CCA has been already
introduced and is being currently used by Telecom
Italia according to its Spec. CT 948, September 2011.
Larger diameter
conductor: 0.75 vs 0.6
mm or
1.14 vs 0.9 mm
(to account for CCA’s
higher resistivity)
Larger cable diameter
(+10%)
Lower cable weight
(–20%)
Same electrical and
transmission
performances
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Jicable’15, 21 - 25 June 2015 - Versailles - France
OPEN ACCESS
LV/MV power cables
Utility, Low Voltage multi-polar cable, concentric neutral conductor of
CCA as an alternative to Copper, ENEL Spec. DC 4126, August 2010
ARG7(E4*)OCR-0,6/1 kV – AUG7(E4*)OCR-0,6/1 kV
3 central core conductors in Aluminum and CCA10% concentric neutral
conductor
Cu vs CCA wires
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Jicable’15, 21 - 25 June 2015 - Versailles - France
LV 4x25mm2 CCA FG7OR 0.6/1.0kV, class 5
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Cable prototypes: building wire 450/750V
Conductor (flexible or class 5)
cross sections:
– Copper 1,5mm2 (reference)
– CCA 2,5 mm2
– Tinned CCA 2,5 mm2
– Aluminum 2,5mm2
Final multicore cables
- FROR 3 x cores
Cable production flow
Insulated core
stranding
Insulation
Extruded PVC (different
colors to indentify the
phase)
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Outer Sheath
Extruded PVC (double
layer: filler +outer
sheath)
Cable prototypes: industrial wire 0.6/1.0 kV
Conductor (flexible or class 5)
cross sections:
– Copper 16 mm² (reference)
– CCA 25 mm²
– Aluminum 25 mm²
Final singlecore cables
- FG7R 1kV 1 x core
Cable production flow
Insulation
Extruded silane cross
linked PE
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Outer Sheath
Extruded PVC
(double layer)
Jicable’15, 21 - 25 June 2015 - Versailles - France
Wire Integrity Test
1. Pr En 3475-514, acid test
Cleaned 1 m wire samples are helically wound and immersed in
concentrated (∼
∼18%) HCl solution for 1 minute at 25°
°C. If the
Cu layer is continuous nothing visible happens. Should an
holiday be present H2 gas evolution becomes visible with the
naked eye
Al CORRODED
2Al → 2Al+++ + 6 e-
Cu PROTECTED
Dissolves in the acid
potential ∼ -1,3 VSHE
6H+ + 6e- → 3H2↑
Hydrogen bubbles
potential ∼ 0 VSHE
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Wire Integrity Test, acid test
Test performed on high quality CCA clad 0.12 mm
wire with no bubbles visible after 1 minute test (left)
and on low quality CCA plated 0.25 mm wire after
some second of test (right)
CCA Cladded
(metallurgical process)
CCA plated
(electrochemical process)
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Wire Integrity Test, basic test
2. Basic conditions
Cleaned 1 m wire samples are helically wound and immersed in
concentrated (∼
∼ 4%) NaOH solution for 4 hours at 70°
°C.
Should an holiday be present Al will be etched locally, the
damage being better seen in low power after-test microscope
examination.
Al CORRODED
2Al + 4H20 → 2AlO2- +
8H++6e-
Cu PROTECTED
2AlO2- + 2NaOH + 2H+ →
2AlO2Na + 2H2O
6H+ + 6e- → 3H2↑
Hydrogen bubbles
scarcely visible
potential ∼ -0,9 VSHE
Forms a gel in the solution
potential ∼ -2,5 VSHE
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Wire Integrity Test Results
Test in
acid conditions
Test in basic
conditions
Material
Wire
o.d.
(mm)
Taken from
stranded
conductor
(mm2)
Ten 1 m wire
samples average
rating for no H2
(minutes)
CCA
0,4
25,0
1,02
CCA
0,2
2,5
0,98
Sn CCA
0,2
2,5
2,47
Material
Wire
o.d.
(mm)
CCA
CCA
Sn CCA
0,4
0,2
0,2
•
Taken from
stranded
conductor
(mm2)
25,0
2,5
2,5
Jicable’15, 21 - 25 June 2015 - Versailles - France
Five 1 m
wire
samples
5
5
5
Outdoor life test scheme
0,5 Ω, 300W
Variac 1
kVA
∼ 24
Vac
15 A
A
mV
A
• 9 feed through terminals
• 8 loops of different conductor wires
• 16 wire terminations in series
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Jicable’15, 21 - 25 June 2015 - Versailles - France
2,0 0,5
hours
Outdoor life test infrastructure
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Results, Cu1.5 mm2 vs CCA, SnCCA, Al 2.5mm2
650
600
ac potential drop (mV)
550
Cu
500
CCA
450
400
CCA Sn
crimped Al burn-out
& substitution ↓
350
Al
300
250
200
150
0
200
400
600
800
1000
1200
Time (hour)
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Jicable’15, 21 - 25 June 2015 - Versailles - France
1400
Al 2.5mm2 samples failed after 500, 1600h
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Water exposure test set up
Single wire and stranded conductors helical samples after
500 hour test in tap water. The Calomel reference electrode
used for electrode potential monitoring also visible.
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Water exposure test results
time (h) to visible
wire ext. from stranded
conductor
Al corrosion spots
diam,
conductor,
material
on 2 wire samples,
mm
mm2
1m length
CCA
0,4
25
50-100
CCA
0,2
2,5
50-100
Sn CCA
0,2
2,5
500
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Salty water test of end cut CCA samples
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Jicable’15, 21 - 25 June 2015 - Versailles - France
Conclusions
CCA is an attractive alternative to Copper
Lightweight, low cost, anti-theft,
critical issue CCA quality
raw material quality (Cu, Al), good metallurgical bonding;
2 methods are proposed to test CCA integrity;
Outdoor life test was defined to understand
conductors behavior in realistic installation and
sever conditions
Results so far achieved demonstrate the
potentiality of application of CCA as flexible
conductor for electric LV power cables.
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Jicable’15, 21 - 25 June 2015 - Versailles - France
contact
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Prysmian SPA, Milan, ITALY
– Alberto BAREGGI, Flavio CASIRAGHI, Luca DE RAI, Silvio FRIGERIO, Davide MARTELLI;
–
–
–
–
–
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alberto.bareggi@prysmiangroup.com,
flavio.casiraghi@prysmiangroup.com,
luca.derai@prysmiangroup.com,
silvio.frigerio@prysmiangroup.com,
davide.martelli@prysmiangroup.com
Prysmian Cavi e Sistemi Italia Srl, Milan, ITALY
– Alessandro MAZZUCATO
– alessandro.mazzucato@prysmiangroup.com
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Dynext Srl, Legnano (Milan), ITALY
– Franco PERUZZOTTI, Antonio PEZZONI;
– franco.peruzzotti@dynext.eu,
– antonio.pezzoni@dynext.eu
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G.B. Studio Sas, Milan, ITALY
– Pietro ANELLI, anellibonvini@tin.it
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Copperweld, Nashville, Tennessee, USA
– Dustin FOX, Syarif YANCE;
– dfox@copperweld.com,
– YSyarif@copperweld.com
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Jicable’15, 21 - 25 June 2015 - Versailles - France