Towed cable systems
Description
The cables of this group are designed for power supply and communication with depth equipment, lowering-rising operations, towing different equipment and similar work.
The main part of this group is a load carrying armoured cable.
Specifications
Two variants of design of a coaxial deep-see cable are shown on figure 1. The first cable has a two-winded steel armour and other has an armoured sheath.
|
|
| KGP
1-190 (variant 1) | KGP
1-190 PL-20,0 Oa (variant 2) |
Picture 1
|
¹ Pos. |
Name of element of construction |
Material of element, dimension |
Diameter mm |
|
|
Variant 1 |
Variant 2 |
|||
|
1 |
Current conductor |
Soft copper wire (4,0 mm2) |
2,6 |
2,6 |
|
2 |
Insulation |
LD polyethylene |
9,0 |
9,0 |
|
3 |
Screen |
1) soft copper wire, soft copper tape |
10,0 |
10,0 |
|
4 |
Taping |
TapePET-E |
10,2 |
10,2 |
|
5 |
Insulation of screen |
LD polyethylene |
13,4 |
12,5 |
|
6 |
First wind of armour |
1) Steel galvanized wire 2) Steel galvanized wire |
16,5 |
15,5 |
|
7 |
Second wind of armour |
1) Steel galvanized wire 2) Steel galvanized wire |
20,0 |
18,6 |
|
8 |
Protective sheath |
LD polyethylene |
- |
20,0 |
Main parameters
|
Electrical: |
|
|
Resistance of current conductor, not over |
4,89 Îhm/km |
|
Resistance of insulation of conductor, not less |
20000 MÎhm/km |
|
Resistance of screen, not over |
3,2 Îhm/km |
|
Resistance of insulation of screen, not less |
20000 ÌÎhm/km |
|
Impedance 5 ÌHz |
50 +/-5 Îhm |
|
Attenuation ration frequency 1 ÌHz |
4 +/-1 dB/km |
|
Attenuation ratio frequency 5 ÌHz |
10 +/-2 dB/km |
|
Mechanical: Variant 1 Variant 2 |
|
|
Weight of cable in air, not over |
1300.…850 kg/m |
|
Weight of cable in water, not over |
536…..195 kg/m |
|
Breaking strength, not less |
190…...100 êN |
OOO “Pskovgeokabel” produces large range of cables for towing different equipment and tools behind a vessel. The most interesting cables are shown on picture 1,2.
EGN
Picture 2
|
¹ Pos. |
Name of elements of construction |
Material of element of construction, Dimensions |
Diameter, mm |
|
1 |
Current conductors of excitation |
Copper, (2,1 mm2) |
1,85 |
|
2 |
Insulation of conductor of excitation |
Copolymer propylene Colours: 1pc.-natural. Periphery: 1 pc.-natural, 1 pc.- red, 1pc.- blue, 1pc.- green |
3,5 |
|
3 |
Optic fiber module |
Standard single mode fiber in copolymer sheath |
0,85 |
|
4 |
Sheath of optic fiber module – power conductor |
Copper tube 1,0/1,62 |
1,62 |
|
5 |
Insulation of module (conductor) |
Copolymer propylene |
3,3 |
|
6 |
Screen |
Aluminium foil |
3,5 |
|
7 |
Core of cable with longitudinal hermetization |
Polyisobutilen on central core |
10,5 |
|
8 |
Intermediate sheath |
LD polyethylene D =1,75 mm |
14,5 |
|
9 |
First wind of load carrying element |
Galvanized steel wire, 30õ1,50 mm |
17,3 |
|
10 |
Second wind of load carrying element |
Galvanized steel wire, 36õ1,50 mm |
20,3 |
Main parameters
|
Electrical: |
|
|
Resistance of conductor of excitation, not over |
10 Îhm /km |
|
Resistance of conductor of copper sheath of module, not over |
25 Îhm/km |
|
Resistance of insulation, not less |
10000 ÌÎhm*km |
|
Optical: |
|
|
Signal attenuation on length waive 1,55 mkm, not over |
0,7 dB/km |
|
Mechanical: |
|
|
Breaking load |
200 ±10 kN |
|
Maximum operating load |
150 kN |
|
Weight of cable not over |
1250 kg/km |
Sections of cables used for towed cable systems are shown below. The typical dimensions of cables comprise the range up to 32 mm for the cable KG-32, which is the heavy towing cable; light cables can be made with diameter up to 9 mm (ÊÃ 2õ(0,7+1ÎÎÂ)+2õ0,35-55-60). Operating loads consist consequently 150 and 25 kN. The cables contain power and signal conductors and optic fibre channels for transmission of information.
|
|
|
| KG-32 | KG (3õ0,2+3õ1ÎÎÂ)-60-60 | KG 2õ(0,7+1ÎÎÂ)+2õ0,35-55-60 |
Fig. 3