Power cable with impregnated paper insulation (copper)
1. Core single or multiwire copper
2. Impregnated paper phase insulation
3. Impregnated paper wrapping insulation
4. Lead case
5. Bedding
6. The armor of steel tapes or wires (Кл)
7. Integument (for cables Б, Б2л, Бл)
The shape of the current-carrying conductor may be sectoral, single block or multiwire. Insulation consisting of paper cable tapes additionally impregnated by oil rosin is applied to the cores of the cable. Each current-carying conductor is isolated from the others, and all together they stranded into one single conductor, the spaces between the conductors are filled with paper sulphate and spun into bands.
Power cables with paper insulation can be manufactured with a lead sheath, copper and armored PVC depending on its environmental condition and sphere of operation. Aluminium sheaths make the cable durable to mechanical damage and add to the tightness of power cables, the lead sheath increases the resistance to the impact of environment (such as alkaline fumes).
The most popular copper power cables with impregnated paper insulation:
- СБ - installation in the ground (trenches) with low and medium level of corrosion activity;
- СБл, СБ2л - is laying in the ground (trenches) with medium level of corrosion activity on the tracks with stray current or without it and in the ground (trenches) with high level of corrosion activity without leakage current on the tracks;
- СБГ - is appropriate to operation on overhead power lines where there are risks of mechanical damage, in explosion hazardous zones;
- СБ2лГ - is appropriate to operation on the air when there are risks of mechanical damage during its exploitation in a dry and damp places (tunnels), in a work places, partly flood buildings with low, medium and high level of corrosion activity.
- СП2л - intended for installation in the ground (trenches) with high level of corrosion activity on tracks with or without stray currents, if it is incurred to serious spread forces.