The composite suspension insulator has the advantages of light weight and high mechanical and electrical strength, so it can be used for urban network reconstruction and erection of compact overhead lines. In particular, synthetic insulators have good anti-pollution flashover performance, and are especially suitable for use in areas with particularly serious pollution, so as to effectively improve the reliability of line operation and reduce line maintenance workload. Compared with porcelain or glass insulators, the excellent antifouling performance of composite suspension insulators is unquestionable, but the lightning resistance performance has two factors. The favorable factor is that it does not have the "zero value" like porcelain insulators and the "self-explosion" phenomenon like glass insulators, so it can maintain a high level of lightning resistance for the entire string of insulators during operation; the unfavorable factor is due to the diameter of the shed. Smaller, the dry arc distance is smaller than that of porcelain (or glass) insulators, that is, the lightning resistance level is less than that of porcelain (or glass) insulators of the same length. The composite insulator is composed of three parts: insulating mandrel, silicon rod plastic umbrella sleeve and connecting hardware at both ends. Insulation mandrel is the abbreviation of epoxy resin glass fiber pulling rod. It is the skeleton of the composite insulator and plays multiple functions such as supporting the umbrella sleeve, internal insulation, connecting the hardware at both ends, and bearing mechanical loads. It has a high tensile strength. Strength, generally up to 600Mpa or more, 2 times that of ordinary steel, 5-8 times that of porcelain materials, and has good dielectric properties and chemical resistance, as well as good bending fatigue resistance, creep resistance and impact resistance sex. The silicone rubber umbrella cover mainly plays the role of protecting the mandrel, blocking rain and snow, increasing the creepage distance and the external insulation of the product. It is based on high molecular polymer silicone rubber, supplemented by flame retardants, It has good hydrophobicity and migration, as well as good corrosion resistance, aging resistance, electrical insulation and other properties. And it has high pollution flashover voltage and shatter resistance, and the voltage distribution is uniform. Compared with porcelain, its flashover voltage is less than 2 times that of porcelain under the same conditions. 1.Each has the advantages of small volume, light weight,the same leavel of porcelain insulator of 1/5-1/9 the left and right sides, ease of transportation and installation. 2.Each composite insulator of high mechanical strength, reliable structure, stable performance, safety margin, the circuit and ensure the safety operation. 3. The composite insulator has superior electrical properties, the silicone rubber shed has good hydrophobicity and migration, good pollution resistance, strong anti-pollution flashover ability, can operate safely in heavily polluted areas, and does not require manual cleaning, and can be exempted from zero measurement. maintain. 4. The composite insulator has acid resistance, alkali resistance, heat aging resistance and electric resistance, good sealing performance, and ensures that its internal insulation is not damp. 5. Brittle resistance of composite insulator can good, shock strength, brittle fracture accident will not occur. 6. Composite insulators are interchangeable and can be used interchangeably with insulators such as porcelain.1.Insulator in the transportation and installation to should take put down gently, and should not be thrown, and to avoid all kinds of miscellaneous pieces of (wire, iron plate, tools, etc.) and sharp hard object collision and friction. 2. When the composite insulator is hoisted, the knot is tied on the end accessories, and it is strictly forbidden to hit the shed or sheath. The rope must touch the shed and the sheath, and the contact part should be wrapped with soft cloth. 3. Do not use the composite insulator as an auxiliary tool for placing (retracting) wires, so as not to damage the insulator due to impact force or bending moment. 4. It is strictly forbidden to step on the insulator umbrella skirt 5. When installing the pressure equalizing ring, pay attention to adjust the ring to make it perpendicular to the axis of the insulator. For the open pressure equalizing ring, pay attention to the same direction of the openings at both ends to facilitate the discharge and protect the umbrella skirt