2025-11-17
The main characteristic of oil-filled cables is that they use a set of devices (such as pressure tanks, gravity tanks, etc.) to replenish impregnating agents to improve the cable's pressure resistance.
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(1) Self-contained oil-filled cable: This type of cable has two structures: single-core and three-core. The voltage level of the single-core cable is 110~750kV, and the voltage level of the three-core cable is generally 35~110kV. Its representative model is CYZQ☐☐ (such as CYZQ241 type), and its structure is shown in the figure.
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Schematic diagram of self-contained oil-filled cable structure
(a) Cross-section of a single-core self-contained oil-filled cable
(b) Outline drawing
(c) Three-core self-contained oil-filled cable
1-Oil channel; 2, 10-Conductor; 3, 11-Conductor barrier; 4, 12-Insulation layer; 5, 13-Insulation shield; 6, 17-Lead sheath; 7-Inner liner; 8-Reinforcing copper tape; 9, 20-Outer sheath; 14-Oil channel; 15-Filling; 16-Copper wire braided tape; 18-Inner liner; 19-Reinforcing layer;
(2) Oil-filled steel pipe cable: This type of cable is generally a three-core structure and is often used for high voltage levels. The steel pipe is the sheath of the cable, and its structure is shown in the figure.
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Schematic diagram of oil-filled steel pipe cable structure
(a) Cross-sectional view (b) Outline view
1-Conductor; 2-Conductor barrier; 3-Insulation layer; 4-Insulation shield; 5-Semi-circular stripper wire; 6-Steel pipe; 7-Anti-corrosion layer;