ACSR/TWD trapezoidal conductor

Applications

ACSR/TWD is ideal for reconductoring: it offers the same diameter for ice and wind but loading at higher ampacity than traditional ACSR designs.

Angle and deadend structures must be carefully evaluated because of the greater weight of the conductor.

The same tangent structures may normally be used in installation.

This conductor is an outgrowth of the technology developed in the manufacture of self-damping conductor ACSR/SD.

Specifications

ACSR/TWD is produced to ASTM B-779

Construction

ACSR/TW is a concentrically stranded conductor of varying layers, made with trapezoidal-shaped 1350-H19 wires over a high strength steel core.

Each conductor is patterned after existing "round strand" ACSR(ASTM B-232), except that trapezoidal aluminum strands replace round strands.

An ACSR/TWD design features equivalent diameter, whereas ACSR/TW offers reduced diameter with equivalent circular mil area.

The same diameter means an increase in aluminum area of more than 20%.

This means a reduction in AC resistance in the order of 15%.

The steel core is increased proportionally to the aluminum in order that existing stress-strain data used for sag and tension be applicable to ACSR/TWD.

The ACSR/TWD design is different from that of "round strand" ACSR in that the trapezoidal layers are not self-supporting.

Intentional gaps between the TW wires are a major part of the design.

This allows gripping devices, such as comealongs, to transfer the clamping load through all layers to the core.

The increased aluminum and steel area means that larger compression fittings are required than would normally be used on the "round strand" ACSR of the same diameter.

Conventional armor rods and suspension shoes, which are diameter-sensitive, may be used.