Mass production has demonstrated satisfactory performance in terms of forming stability, production efficiency, aluminum sheath quality and power consumption. Using four feedstock rods to extrude corrugated aluminum sheathing for HV power cables, Dalian Konform applied its latest R+D progress on “SSLB500”, a continuous sheathing line for Shenyang Furukawa Cable, a wholly owned subsidiary of Furukawa Electric.

A Continuous sheathing process has been used in recent years to manufacture aluminum sheath for HV power cables. In the previous process, two feedstock rods are fed into two grooves on one extrusion wheel, resulting in a twin-channel continuous sheathing process. The maximum diameter of product supported by this sheathing process is 165mm. However, once a sheathed product is wider than diameter 120mm, problems such as short tooling life, complex die design, high extrusion pressure, and poor forming stability begin to emerge. Most of these issues are caused by an asymmetry of die structure and complex metal flow.

Researchers of Dalian Konform developed a new “four-channel” sheathing process. A pair of extrusion wheels, each with two grooves, rotate synchronously and drive four bars of precursor material through corresponding channels into the welding chamber, weld together under high temperature and pressure, and flow through annular extrusion dies to form the sheathing layer on the outside of the cable. This process has a working range from 60mm to 180mm in diameter with a wall thickness between 2mm-8mm.

Mass production of 66kV/400mm2, 110kV/1000mm2, and 220kV/2500mm2 HV power cables has demonstrated satisfactory performance in terms of forming stability, production efficiency, aluminum sheath quality and power consumption. The roundness of the extruded aluminum tube reaches 99% and the thickness deviation is within ±5%. The average output of aluminum sheath is 738kg/h when the main shaft runs between 6r/min~7.5r/min and the burn rate is about 5%. The average energy consumption is 440kWh/ton.

“The success of SSLB500 has proved that the ‘four channel’ sheathing process is superior to previous processes in the market,” says Mr. Fan Zhixin, general manager of Dalian Konform. “We are currently working on the further development of aluminum sheathing for other cable products such as the superconducting Rutherford cable, and we would be pleased to develop production lines tailored to our clients’ requirements.”

Dalian Konform Technical Company Ltd.

19 Longtian Road,

Longtou Science and Technology Industrial Park,

Lushunkou District, Dalian, P.R. China

Contact person is Pei Jiuyang

Tel.: +86 411 86286520

Patrick@konform.cn

www.konform.cn