General Construction
Conductor
The conductor shall be composed of plain copper or aluminum wires complying with IS: 8130-1984. Mining Cables to be used in gassy mines shall be of copper conductor only.
Insulation
The conductors are insulated with suitably compounded PVC, which is applied to the conductor by extrusion process.
Inner Sheath
For all cables having two or more cores, a common covering (inner sheath) is provided over the laid up cores either by extrusion or by wrapping of plastic or proofed tapes. Single core cables do not require inner sheath.
Armouring
Depending upon the application, the cables can be armoured. The armouring can be Round Steel Wire or Steel Strips. In case of cables where diameter over the inner sheath does not exceed 13 mm, the armour consists of Galvanished Round Steel Wires; above this size, the armour can be Galvanished Flat Steel Strips or Galvanished Round Steel Wires as per customers' requirement. In case of single core cables intended for use of an A.C. Systems, the armouring shall be of Aluminium Wires/Stripes or any other non-magnetic material.
Armouring of PVC Mining Cables consist of Galvanised Round Steel Wires/Strips, but wherever necessary, a few Tinned Copper Wires/Strips are also included to meet the resistance requirements of armouring for Mining Cables.
Outer Sheath
Over the armouring, or in case of unarmoured cables, over the inner sheath (for single core cables over the insulation), a tough outer sheath of PVC is applied by extrusion. This is normally Black in colour. This provides a tough but smooth outer covering to PVC Cables. The trademark "Arrow" are embossed on the outer sheath. Wherever desired the customer name can also be embossed on the cable. The embossing script repeats at desired length of cable.
