Why is Steel Tape Armoured Cable Wrapped with a Layer of Steel Tape on the Outer Layer?

Steel tape armoured cable is a power transmission conductor with a metal steel tape as the outer sheath. Its core features include a spiral winding structure, a cold-rolled steel tape substrate and an anti-corrosion coating system. The existence of its steel tape layer is essentially to build a multi-level mechanical protection system to cope with physical invasion in a complex laying environment.

When the steel tape armoured cable is subjected to heavy surface loads or rock and soil lateral pressure, the spirally wound steel tape absorbs the impact energy through plastic deformation and converts the point load into a stress field distributed in a strip shape. The high yield strength of cold-rolled steel prevents external forces from being transmitted to the internal insulation layer, avoiding the dielectric strength attenuation of the main insulation due to deformation.

The interlocking structure of the steel tape edge forms a continuous force chain under tensile conditions, allowing the traction force to be evenly transmitted along the spiral path. This design allows the conductor to only carry electrical loads, eliminates the risk of mechanical stress damaging the copper core lattice structure, and maintains the long-term stability of conductivity.

In addition, the steel tape is a biological and chemical protection barrier. It can isolate the penetration of rodent tooth tips and hinder the axial penetration of corrosive media.

Does the steel tape layer affect the current carrying capacity of the steel tape armoured cable?

The heat generated by the hysteresis loss of the steel tape can be compensated by heat dissipation design. The helix angle is optimized to control the energy consumption of magnetic domain steering in the alternating magnetic field, and the surface roughness of the coating enhances air convection heat dissipation. Under the comprehensive thermal balance, there is no substantial restriction on the rated current.