Both we all know for the suspension type insulator there are two different material suspension type insulator, porcelain ceramic suspension insulator and composite polymer suspension insulator:

Material
Good commercial wet-process porcelain
Composite silicone rubber

Standard
ANSI C29.1 & ANSI C29.2
IEC

Connection ways
Sockets & Ball
Clevis & Tongue

Color
Porcelain: Brown glazed, Grey glazed, White glazed
Silicone rubber: Grey and Red

Certificates
ISO 9001 certificate, test report, type test, route test
5000 hour aging test, ISO 9001 certificate, test report
Compare with porcelain ceramic suspension type insulator, composite suspension type insulator also have some disadvantage:

Disadvantages:
The price of composite insulator is higher than porcelain insulator
Since the raw material is silicone rubber so composite insulator have soft surface, so the sealing performance is easy to break when tough objects, result in decrease of insulation properties

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