Polymer Insulator in China

05-06-2022

The very first composite insulators in China were developed around 1984 and came mainly from research conducted at two universities – Wuhan Hydro & Electric University, now integrated into Wuhan University in Wuhan, and Tsinghua University in Beijing. This research and knowledge eventually was disseminated to all the leading Chinese insulator manufacturers, who then derived much of their original know-how and production technology from one of these two academic institutions.

The very first local supplier of these insulators in China began operations about 20 years ago in the small city of Xiangfan,located a few hours drive from Wuhan. Xiangfan Guowang Composite Insulators Co., Ltd. was first established in 1987 and began shortly later offering silicone nsulators for up to 110 kV, gradually working its way to 500 kV. Today, the firm has grown to become one of China’s largest producers of composite line insulators, supplying units for even the most demanding UHV applications.

With an annual production capacity of some one million pieces (calculated on the basis of 110 kV equivalents), Xiangfan Guowang may well be the world’s largest supplier of composite line insulators, based on volume alone. Indeed, the scale of its manufacturing operation is by any measure impressive with a huge number of units in process at any single step.

The existing 20,000 sq. meter plant, built in 1997, produces silicone insulators using both traditional production methodologies –shed-by-shed assembly, which currently accounts for about 60 percent of annual production and single piece molding which makes up the balance. One of the unusual aspects of the company’s production technology is a second curing operation, which is done not only on all silicone sheds used for assembled units but also to those units manufactured in several shots in an injection molding machine.