In recent years, a large number of promotion our country adopted the suspension insulator toughened glass, high mechanical strength of the insulator (for 2 ~ 3 times of porcelain insulator), electric performance is good (under shock wave is 3.5 times of the average breakdown strength of porcelain insulator), long service life, not easy ageing, convenient maintenance, good self-cleaning, it is the biggest characteristic of zero since the break, namely when insulator lost insulation or mechanical load, the umbrella skirt will automatically break off, easy to find, can be replaced in a timely manner.
And epoxy resin insulators, fluoroplastics and silicone rubber disk-rod insulators and semiconducting glaze insulators have been developed and used in China.Semiconducting glaze insulators greatly extend the cleaning cycle of insulators and improve the reliability of power supply. The trial results are good, but there are some disadvantages such as large leakage current.The ideal new type of insulator is composite polymeric insulator.This kind of insulator is made by combining two kinds of polymeric materials, one of which improves mechanical strength and the other improves insulation performance, so that composite polymeric insulators can meet the requirements of high mechanical strength, good insulation performance, impact resistance, light arc resistance, etc., which is also the future development direction of insulators.