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What’s new with Copperweld!
Exciting developments inCopperweld® copper-clad steel
(CCS) conductors
Copperweld® 4THOUGHT™A New Alternative to 4/0 Solid Copper
4THOUGHT™ provides resolution to these challenges and more!• 4THOUGHT™ is a 4/0 CCS (copper-clad steel) strand with the same diameter as 4/0 copper
– No additional expense for new Cadweld® molds • 4THOUGHT™ uses smaller size rod material making it just as flexible as copper
– Eliminates the stiffness issue• 4THOUGHT™’s steel core provides greater breaking strength as compared to 4/0 copper ——> 1000 lbs stronger • 4THOUGHT™ is generally less expensive than 4/0 copper• 4THOUGHT™ is an outstanding theft deterrent since the steel core reduces the scrap value to that of steel• Fushi Copperweld’s proprietary manufacturing process ensures a permanent metallurgical bond between the copper
jacket and steel core that is devoid of oxygen– Eliminates any concern regarding corrosion
Prior configurations of Copperweld® DSA strand have long been available for substation grounding purposes and provided a mechanically stronger conductor than 4/0 copper. However, these configurations also evidenced more stiffness due to the stronger steel core.
Challenges The larger diameter required different cadweld type molds, an added expense for the installers
The larger diameter added more stiffness than 4/0 copper
4THOUGHT™ Specification Details4THOUGHT™ is composed of 40% IACS dead soft annealed copper-clad steel.
The values below are only validated for genuine Copperweld® THOUGHT™ 4/0-compatible strand
manufactured by Fushi Copperweld Inc.
4THOUGHT™ compared to 4/0 CopperConsiderations Copper Clad Steel Copper
Industry Standard Other configurations widely adopted ina variety of conductor applications 4/0 Copper
IEEE Position Viable alternative especially for high-theft areas Cu is most commonly used for grounding
Merits of each product compared:
Breaking Strength 4THOUGHT™ = 5,979 pounds 4/0 = 4,933 pounds
Fusing Current @ 30 Cycles (0.50 sec) 4THOUGHT™ = 28.60 kA 4/0 = 42.67 kA
Flexibility Easy to form Easy to form
Connectorization Exothermic & mechanical Exothermic & mechanical
Theft Resistance Yes: No scrap value No: High scrap value
Dimensions Same Same
Cost Slightly less expensive than copper More expensive than CCS
Pricing volatility Less affected (36% copper by volume) Severely affected (100% copper)
Further questions? We have a very close relationship with Fushi Copperweld’s engineering team, and we’ll be happy to get you the answers!
What’s new with Copperweld® Pole Ground
• New jacketed version is designed to NOT have the appearance of copper pole ground:
– Jacket material is UV-stabilized PVC
– Color is GREY– Currently available for solid pole ground only
– Target release date is July 2010
– Photo is prototype; final product may vary in appearance
New CAMO™ Colored Pole Ground
• Green spool easily identifies the pole ground as Copperweld® (solid copper material is shipped on a black spool).
New Green Spools
What’s new with Copperweld® Pole Ground (cont’d)
• New stranded version offers greater flexibility and ease-of-handling while matching the strength of solid copper
– Sizes available are #2 and #4 stranded 40% DSA
– Same cost as single pole ground
– Package Options: 25 lb equivalent spool (same footage as solid CCS)
– Weighs less per foot as compared to the copper equivalent
– Available now for use
New Stranded Pole Ground
Selecting the rightCopperweld® products
to optimize grounding systems
The Traditional Selection ProcessHas Been Replaced
Selecting The Right Copperweld® Strand For Your Application
• Design Engineers should be concerned with two factors when selecting a conductor for a ground grid– The conductor must meet the maximum fault current for a certain duration– The conductor must meet a minimum breaking load as required by the substation design (typically
5,000 pounds)• Traditionally, we have used a chart comparing the ampacity ratings of copper and Copperweld® CCS that
allowed the user to visually select the Copperweld® equivalent.• For example:
– The equivalent to 4/0 copper per the graph is 19#9 40% DSA– A typical maximum fault current for a distribution substation is ~18kA at 30 cycles– A 2/0 Copper or 7#6 CSS conductor will meet this requirement instead of the larger size 4/0 copper
commonly used for ground grids • 7#6 CCS Conductor safety margin – 30%
– Most engineers upsize to 4/0 copper in order to meet the mechanical strength requirement– 7#6 CCS meets the fault current and mechanical strength requirements– The advantage of CCS in this case is the cost savings— at least 25% per foot!
• What we have learned: A new method is needed for the selection process!
Simple New Computerized Selection Program for Sizing Copperweld®
• Entering the fault current, with a safety factor (if required) and fault duration is all that is needed to determine the appropriate size Copperweld® conductor
18kA with 30% Safety
Factor Value
Validating the data that drives the newprogram for sizing Copperweld®
• To confirm the values used in this program, Fushi Copperweld conducted fusing current testing at a third-party laboratory.
• The primary purpose of the testing was to determine the accurate fusing of Copperweld®
conductors with respect to how IEEE Standard 80 rated copper-clad steel conductors.
• For this testing, “fusing” was defined as any physical change to the conductor that would prevent the conductor from handling an additional short circuit current of the same magnitude and duration.
• The testing validated the fusing current of copper matched exactly the fusing current calculated using IEEE Std 80 formula.
• However, the testing also revealed that Copperweld® conductors can carry 105 – 108% of the calculated current using the IEEE Standard 80 formula.
Demo Time
ADVANTAGE: COPPERWELD®
• Copperweld® 4THOUGHT™ 19-wire CCS strand is entirely suitable as a stronger, more cost-effective, and replacement for 4/0 copper in most substation grounding applications
• Copperweld® CAMO™ colored pole ground is specifically designed to further deter theft by masking its resemblance to copper
• Lightweight stranded Copperweld® pole ground offers greater flexibility while matching the strength of solid copper, at the same cost of single-wire ground
• New green spools make Copperweld® products identifiable at a glance on the truck or at the warehouse
• Old fusing charts replaced with a simple-to-use computer sizing calculator
Copperweld®
(Copper-Clad Steel)
Earthing (Grounding) Wire for use in
Electrical Utility Applications
Product Features• Bimetallic wires combine the features of dissimilar metals to achieve a cost
and/or a performance advantage
• Copper-Clad Steel
- Conductivity of copper (high frequency applications) - Strength of steel - Fatigue Resistant - Corrosion resistance - Fusing current similar to copper - Durability - Low scrap value - Excellent theft resistance
Cooling
Take-up
Copper
Steel
Copper Thickness6% of total diameter for 30%10% of total diameter for 40%
Solid Metal Cladding Process
Copperweld is a composite in which a concentric copper cladding is metallurgically bonded to a steel core through a continuous, solid cladding process using pressure rolling for primary bonding that seals out moisture.
Metallurgical Bond
0
20
40
60
80
100
0 100 200 300 400 500 600 700 800
Cu
Fe
Com
post
ion,
wt%
Distance, nm
STEM-HAADF-XEDS with drift correctionAs tested by University of Alabama
Tuscaloosa, Alabama
Copper-Clad Steel Production Process
Hard Drawn Annealed
Bimetallic Wire Quality
• Must have:– Exceptional bond integrity to prevent copper
separation and moisture penetration– Highest Quality Raw Materials
• Poor (Dirty) Steel results in premature breakages; lower strength; and poor bond
• Poor (Dirty) copper results poor signal and current transmission; lower conductivity; and moisture and corrosion propagation points.
Bimetallic Wire Quality
Poor Quality Producer Low Carbon 40%COPPERWELD® Low Carbon 40%
Bimetallic Wire Quality
COPPERWELD® Low Carbon 40% Poor Quality Producer - Low Carbon 40%
Grounding Products (CCS)
• Available in Single End (pole ground), 3, 7 and 19 strand
• Types
– Dead Soft Annealed (DSA) wire for greater flexibility
– High Strength & Extra High Strength for overhead
grounds/messenger wire/down guys
• Oxygen-Free Copper Cladding
• 30% & 40% Conductivities
• THEFT RESISTANT
– Some utilities reporting one incident per day
• Combination of Hard Drawn Copper and 30% Copperweld
• Lighter weight compared to copper, provides minimum sag over longer spans
• Higher ampacity over standard Copperweld strand
• Ideally suited for corrosive environments
• 30 different sizes & combinations
• THEFT RESISTANT
Type A
Type EK
Type G
Some Examples
Composite Conductors (CCS)
FAQs
• Question:
What does the percentage conductivity mean?
• Answer:
– For the Copperweld product, when you see the reference “40% Conductivity”, this is the percentage of conductivity the Copperweld material has as compared to its diameter equivalent of copper.
– If this was for a continuous current carrying condition, then the Copperweld product would not be suitable.
Grounding Applications
• Transmission– Structure Grounding– Counterpoise
Grounding• Distribution
– Ground Connections– Pole Ground Wires
• Substation– Ground Grid
Provides the same
“System Reliability”
as Copper
Grounding Applications
Buried Counterpoise Wire
Generation Plant
Building Ground
Lightning Protection
Substation GroundingGrid Wire
TransmissionLine
R
Switch Yard &TransmissionSubstation
Grounding Applications
Sub Transmission Line DistributionSubstation
DistributionLine
Fence Ground
Pole GroundWire
TransformerGround
Pole GroundWire
Copperweld® CCS for Pole, Structure, and Substation Grounding
• Theft resistant• High mechanical strength
• has approximately 100% more breaking strength than copper conductors.
• Excellent fatigue properties• Ample current carrying capacity & provides
reliable low impedance path to ground• Lower cost over life of installation• 8-12% lighter than copper• Resist fusing at high temperatures• 5 to 6 times the conductivity of ordinary steel
wire• Corrosion resistance
Copperweld is Compatible with Standard Connectors
• Bolted Clamps
Cadweld ProcessCable codes: Pg B-3 in their catalog
FAQs• Question:
Steel is sacrificial to copper. What happens when I cut the wire? Won’t this expose the steel? Will this allow the conductor to corrode?
• Answer:– For corrosion to occur between dissimilar
metals, you must have an anode (steel), a cathode (copper), and an electrolyte (moisture).
– Given the bond achieved between the thick copper cladding and the steel core, no moisture can migrate into the interface between the cathodic material and the anodic material.
– This precludes corrosion from propagating further into the wire.
– Based on analysis of old buried wire samples, corrosion will only advance into the cut end a maximum distance of twice the diameter of the wire. At this depth a rust barrier is formed and effectively seals out the moisture. Without the electrolyte the corrosive action ceases.
– Also, when Copperweld is cut, the copper cladding cold flows to partially cover the cut end. This reduces the area of exposure of the steel.
• Use of Copperweld in buried conditions has prompted questions regarding the effect of corrosion on performance
• Five year corrosion study was initiated using destructive and non-destructive test along with microscopic analysis to evaluate
• Samples were buried in various soil conditions with monitoring systems to check soil PH, moisture, conductivity and temperature
• Second year results support our claim that– The Copperweld wire does not become hollow tubes– Exposing the steel core does not compromise performance
Copperweld Corrosion Test
Corrosion Study (continued)
Depth of corrosion was 0.056 inches,
70% of the diameter
Corrosion Scab seals off exposed steel and prevents
further deterioration
Corrosion Concerns
• Question:– In Galvanic corrosion,
steel is sacrificial to copper. What happens when I cut the wire and expose the steel? Will this allow the steel to corrode and leave a hollow copper tube?
• Answer:– For galvanic corrosion to occur between
dissimilar metals, you must have an anode (steel), a cathode (copper), and an electrolyte (moisture).
– A Superior bond means no moisture migration between the cathodic material and the anodic material.
– Based on current and historical studies, corrosion will only advance into the cut end a maximum distance of twice the diameter of the wire. At this depth a rust barrier is formed and effectively seals out the moisture. Without the electrolyte the corrosive action ceases.
– Also, when Copperweld is cut, the copper cladding cold flows to partially cover the cut end. This reduces the area of exposure of the steel.
Grounding
• All energized electric power systems require grounding (earthing) for safety and protection of personnel and equipment
• This applies to power transmission & distribution, railroads, and commercial & industrial power systems
• Typical applications include pole grounds, substation grounds, counterpoise, mats, etc.
CCSGroundingwire
FAQs
• Question:
How does the flexibility compare to Copper?
• Answer:
– With the steel core, the Copperweld product is somewhat stiffer, but the stranding configuration is flexible enough to shape easily for all applications
– You may experience some complaints from the lineman, but given the choice between replacing stolen material numerous times verses the stiffness, the theft deterrent issue always wins!
FAQs
• Question:
How durable is the copper jacket, our operations group is concerned with impact damage from shovels or hammers?
• Answer:
– The copper jacket is permanently bonded to steel and cannot be separated
– To compare, we performed to test to determine the amount of force to cut #6 copper pole ground. That same force applied to the Copperweld product only dented the outside surface. The steel was not exposed.
Fatigue Comparison to Solid Copper
• Steel core provides fatigue resistance
• Copper cladding provides conductivity
• More durable than solid copper
Durable !
ASTM SpecificationsSpecifications• ASTM B 227 - Hard-Drawn Copper-Clad Steel Wire• ASTM B 228 - Concentric-Lay- Stranded Copper-Clad Steel Conductors• ASTM B 229 - Concentric-Lay-Stranded Copper & Copper-Clad Steel
Composite Conductors• ASTM B 452 - Copper-Clad Wire for Electronic Application• ASTM B 910 - Annealed Copper-Clad Steel Wire.
Test Methods• ASTM B 193 - Resisitivity of Electrical Conductor Materials• ASTM E 8 - Tension Testing of Metallic Materials