Optical Ground Wires (OPGW) Presented by NSW (Norddeutsche Seekabelwerke GmbH) 4-Nov-13 / 1
NSW The Company Plant Overview 4-Nov-13 / 2
NSW Ground Wire History Our Experience Ground Wire Cables production since 1960 s Fiber Optic Ground Wire cable production since 1980 s More than 100 years experience in cable armoring 4-Nov-13 / 3
NSW Ground Wire History The History NSW Ground Wire History and Design Development over more than 50 years Copper Ground Wire Cables Hybrid Electro / Optical Ground Wire Cable OPGW with Stranded Steel Tube FO - Central Plastic Tube Central Aluminum Buffer Tube Design 4-Nov-13 / 4
NSW Ground Wire History Copper Ground Wire Cables Start of production early 60`s Stranded copper star quads (four wires) PE-HD Jacket Armoring wires (one and two layers) 4-Nov-13 / 5
NSW Ground Wire History OPGW with Stranded Steel Tube Stranded FO single tubes (steel) Armoring wires (one and two layers) 4-Nov-13 / 6
NSW Ground Wire History FO - Central Plastic Tube FO - central Plastic tube Armoring wires (one and two layers) 4-Nov-13 / 7
NSW Designs Central Buffer Tube Made of Stainless Steel Fibers are placed in a stainless steel tube tube in the center of the cable, protected by one or more layers of armoring wires. high fiber counts small outer diameter high fiber excess length protective tube only low crush resistance additional weight careful installation 4-Nov-13 / 8
NSW Standard OPGW Design Central Aluminum Buffer Tube Fibers are placed in a aluminum tube in the center of the cable, protected by one or more layers of armoring wires. high protection against mechanical and electrical loads high fiber counts small outer diameter higher fiber excess length good thermal performance Limited outer diameter with single layer design 4-Nov-13 / 9
NSW New Single Layer OPGW Design Big Central Aluminum Buffer Tube with enhanced Wall Thickness Fibers are placed in a aluminum tube in the center of the cable, protected by one layer of armoring wires (mostly ACS). highest protection against mechanical and electrical loads highest fiber counts small outer diameter higher fiber excess length Very good thermal advantage X Limited outer diameter with single layer design 4-Nov-13 / 10
OPGW Design Criteria Main reasons for NSW to investigate and develop the aluminum central buffer tube design 1. Conductivity 2. Corrosion 3. Fiber excess length 4. Various diameters with single layer design reduce weight 5. Capability to use thicker ACS-Wires for better lightning protection 4-Nov-13 / 11
Temperature Change/K Conductivity Sample: AA/ACS 41/41 with St-Tube 286 T lt i T tr i T BA i T F i 250 200 150 100 AA - wire Steel tube ACS - wire 50 Fiber 0 0 5 10 15 20 25 30 t i Time / s 4-Nov-13 / 12
Temperature Change/K Conductivity Sample: AA/ACS 41/41 with Al-Tube 180 AA - wire T lt i T tr i T BA i T F i 150 100 50 Aluminum tube ACS - wire Fiber 0 0 5 10 15 20 25 30 t i Time / s 4-Nov-13 / 13
Max. Temperature / K Conductivity Comparison Al-St-Tube AA/ACS 41/41 High Current Test I 2 t = 64 ka 2 s 350 300 Al-Tube St-Tube 250 200 150 100 50 0 AA Wires ACS Wires Tube Fiber 4-Nov-13 / 14
Elongation Attenuation change Fiber Excess Length Conventional Design: Fiber Excess Length Design: Elongation Cable Fiber Conventional design Contraction 0 Tension CBT 4-Nov-13 / 15
Attenuation change (1550 nm) / db Fiber strain / % Fiber Excess Length NSW Design Philosophy 1,0 No stretching 0,8 of fibers if cable is elongated 0,6 0,4 0,2 0,0 Fiber strain / % Enough safety Attenuation / db 1,0 0,8 0,6 0,4 0,2 0,0-0,2 Included in the design 0 0,2 0,4 0,6 0,8 1 Cable strain / % -0,2 4-Nov-13 / 16
Central Buffer Tube Design Highest protection of fibers Low weight of cables means less additional loads on towers Central buffer tube allows a wide range of fiber count within the same cable type Long experience in manufacturing armored cables, including extended knowledge in preforming of armoring wires Extensive type testing demonstrates high performance safety Minimized corrosion problems with compatible structure Capability for better lightning protection in single layer designs 4-Nov-13 / 17
Central Buffer Tube Design Single layer design - low cost producer depending on volume - use of aluminum clad steel wires or a mixture of aluminum alloy wires and aluminum clad steel wires Multi layer design - low torsion due to pre-forming of wires - load bearing elements (inner layer) are well protected against lightning - thermal advantages - use aluminum wires, aluminum alloy wires and aluminum clad steel wires 4-Nov-13 / 18
NSW Famous Crossings Special Engineering Difficulties Suez Channel Crossing Installation in China Bosphorus Crossing 4-Nov-13 / 19
NSW Famous Crossings Special Engineering Difficulties 500 kv Suez Canal Crossing Customer: EEA, Cairo / Egypt Purpose of the Link: Connection of the 500 kv network of Egypt with Sinai Peninsula and interconnection to Jordan Contractor: Siemens AG Erlangen / STFA Ankara Time Schedule Contract Award: March 1996 Energizing: June 1998 Egypt 4-Nov-13 / 20
NSW Famous Crossings Special Engineering Difficulties Ratings 500 kv Suez Canal Crossing Max. Voltage: 525 kv Max. Power (AC, therm., DIN): 2800 MVA/cct. Towers: 220 m high Crossing Suspension Towers equipped with elevator and aircraft warning lights Number of Circuits: 2 Conductors per Phase: 3 Size of Conductor: AACSR/AW 290/64 mm² Shield-wire: 2 OPGW AA/ACS 136/134 Insulators: Cap and Pin Type, Porcelain Fittings: Double Suspension and Triple Tension String Pile foundation: with 77 piles 0.75 m diameter 4-Nov-13 / 21
NSW Famous Crossings Special Engineering Difficulties Cable Design : Central element :buffer tube, filled 3.80 mm 1st layer : 7 Al-clad steel wires (AW) 2.80 mm 2nd layer : 12 Al-clad steel wires (AW) 3.10 mm 3rd layer : 18 Al-Alloy wires (AY) 3.10 mm Mechanical data, measurements and weight : TYPE : ASLH-DABBB1x24E9/125(AA/ACS 136/134) Diameter (approx.) : 21.8 mm Weight of Cable (approx.) : 1305 kg / km Rated Tensile Strength : 201 kn Modulus of elasticity : 109 kn/mm2 Cross-section AW : 133.7 mm 2 Cross-section AY : 135.9 mm 2 Cross-section ratio : 1.0 Load-bearing cross-section : 269.5 mm 2 Everyday stress (20 % RTS) : 149 N/mm 2 Nominal transient current (T INITIAL = 20 o C) : 15.4 ka (1s) DC resistance (T=20 o C) : 0.18 Ω / km Coefficient of linear expansion : (10-6 ) 15.3 1/K Deflecting radius / Bending radius (min.) : 440 / 330 mm 4-Nov-13 / 22
NSW Famous Crossings Special Engineering Difficulties OPGW Project Suez Crossing 4-Nov-13 / 23
NSW Famous Crossings Special Engineering Difficulties 380/735 kv Bosphorus Crossing Customer: TEAS / Turkey Purpose of the Link: Interconnection of European and Asian Grid with third Bosphorus Crossing using four 420 kv Circuits in first stage Contractor: Siemens AG Erlangen / STFA Ankara Contract Value: 27 Mio. US$ Time Schedule Contract Award: Dec. 1997 Energizing: Dec. 1998 Turkey 4-Nov-13 / 24
NSW Famous Crossings Special Engineering Difficulties 380/735 kv Bosphorus Crossing Ratings Max. Voltage:420 kv (upgradable to 800 kv) Max. Power (AC, therm., DIN): 1600 MVA/cct Distance: 3.1 km (Crossing Section) Number of Circuits: 4 Conductors per Phase: 1 Size of Conductor : AACSR/AW 1802/226 mm² Shield-wire: 2 OPGW AW330 mm² Insulators: Cap and Pin Type, Glass Fittings: 4 x 20 psc. (Double V-Suspension String) 2 x 22 psc. (Double Suspension String) 2 x 20 psc. (Double Tension String) 4-Nov-13 / 25
NSW Famous Crossings Special Engineering Difficulties Cable Design : Central element : buffer tube, filled 6.00 mm 1st layer : 9 Al-clad steel wires (AW) 3.00 mm 2nd layer : 15 Al-clad steel wires (AW) 3.00 mm 3rd layer : 20 Al-clad steel wires (AW) 3.20 mm Mechanical data, measurements and weight : TYPE : ASLH-DABBB1x22E9/125(ACS 300) Diameter (approx.) : 24.4 mm Weight of Cable (approx.) : 2350 kg / km Rated Tensile Strength : 407 kn Modulus of elasticity : 162 kn/mm 2 Cross-section AW : 330.5 mm 2 Load-bearing cross-section : 330.5 mm 2 Everyday stress (20 % RTS) : 246 N/mm 2 Nominal transient current (T INITIAL = 40 o C) : 18.0 ka (0,5 s) DC resistance (T=20 o C) : 0.26 Ω / km Coefficient of linear expansion (10-6 ) : 12.6 1/K Deflecting radius / Bending radius (min.) : 490/370 mm 4-Nov-13 / 26
NSW Famous Crossings Special Engineering Difficulties 380/735 kv Bosphorus Crossing Europe Asia 64m 161m Bosphorus 161m 64m 88m 127m 73m 70m 153m 158m 728m 1884m 502m 4-Nov-13 / 27
Thank you for Your Attention! 4-Nov-13 / 28