132 kV composite silicon rubber insulator

What is Composite suspension insulator

Composite suspension insulators are insulated by a composite structure composed of two or more organic materials with a long rod type. The composite suspension insulators operating in the power grid are mainly rod-shaped suspension insulation, which accounts for more than 95% of the total number of various operating composite insulators in China.

Biref history of GW's composite suspension insulator

Xiangyang Guowang Composite Insulators Co., Ltd. (GW) is located in Xiangyang, China, and has been serving the field of 132 kV composite suspension insulator for more than forty (20) years throughout world and other countries. In the 1980s GW was the first company who use silicone rubber composite materials for insulators’ housing and sheds. The extensive experience in composite suspension insulator has made GW become the market leader in China and many other countries.

Adavanges of GW's composite suspension insulator

• Twenty (20) years of experience in design and production of composite long rod insulator technology.
• High quality HTV silicone rubber made, optimized, applied for the purpose of application.
• Productcomposite long rod insulators with voltage from 10 kV to 1000 kV, which applicable for both distribution and transmission system.
• Injection moulding process and modular process.

This objects to supply silicon rubber insulators to be used as a suspension and tension string for overhead transmission lines with a nominal voltage of 132kV.

Core

The core shall be glass fiber reinforced epoxy resin rod (FRP) of high strength. Both glass fiber and resin shall be optimized in the FRP rod. Glass fibers with low content in alkalis shall be boron free E glass or boron free electrical corrosion resistant (CR) glass.

Use Of resin with hydrolysis trend due to water penetration should be prevented. i.e. matrix of the FRP rod shall be hydrolysis resistant. Suitability of e POXY matrix as well as interface between matrix and fibers has to be considered as design parameter to prevent brittle fracture The FRP rod should be void free.

Hosing

The core of the composite insulator shall be completely covered by a continuous housing consisting of a sheath-weathershed . the molding of entire weathershed structure on the rod shall be employed in a one shot molding process to avoid multiple interfaces. hardware i.e. metal fittings may be installed on the rod prior to molding of the shed controlling molding lines.

The base polymer should be 100% silicon rubber prior to the addition of reinforcing fillers. The thickness of compounding material on core should be minimum 4 mm.

Manufacturer should furnish a description of his quality assurance program including fabrication, testing and inspection for any material (i.e. rubber), components (i.e. rod) or hardware (i.e. end fittings).

Insulator should have hermetically sealed structure in which the housing material is molded to cover the interface between end fittings and FRP rod. this sea should never be broken during testing.

End fittings

The composite insulators shall be socket and ball type with the necessary coupling arrangement such that pin shall move freely in the socket but do not get disengaged under various operating and atmospheric conditions. The socket &ball type metal end fitting should be designed to transmit the mechanical load to the core and the end fittings, both of them will make a uniform and consistent mechanical strength. Materials and methods used in the fabrication of metal parts should be selected to provide good toughness and ductility.

Metal end fittings should be made from a quality malleable cast iron or forged steel or Spheroid Graphite lron(SGI) and should be hot dipped galvanized in accordance with EN 1S01461.

Metal end fittings should be uniform and without sharp edges or corners and should be free of cracks, flakes, slivers, slag, blow-holes shrinkage defects and localized porosity. 

The attachment to the FRP rod should be performed with a symmetrically controlled crimping method control by acoustic method that compresses the metal radially onto the rod without damage to the rod fibers or resin matrix while providing a strength equal !o or greater than the defined and specified ultimate strength to the insulator. The material used in fittings should be corrosion resistant.

Nominal dimensions of the pin , ball and socket interior should be in accordance with the standard IEC60372. No joints in ball & socket or pin (or others) will be allowed.

Outer portion of ball or socket should be zinc sleeved with minimum 99.95% purity of electrolytic high grade zinc.

The finished surface should be smooth and should not crack or get chipped due to ageing effect under normal and abnormal service conditions or during transmit and erection. The design of the fittings and the insulators should be such that there is no local corona formation or discharges.

Production Capacity of composite suspension insulators

Xiangyang Guowang Composite Insulators Co., Ltd was established in 1997. The company covers an area of more than 37,000 square meters. The enterprise has a production capacity of 1 million 220 kVcomposite suspension insulators per year.