Pin insulator can be divided into porcelain pin type insulators and composite pin insulators. Composite pin insulators are one main of silicone composite insulators. Pin insulator is used to insulation and connection between conductive body and grounding body, such as bus support and disconnected insulators, etc. It consists of silicone rubber shed and housing, top& bottom fitting, all the components was assembled with cement together.

The ways of inspecting Silicone composite insulators
◆ Conduction - Heat flowing through contact. Your biggest concern. Create a dead air space around you can. Maybe with a foam like great stuff. Look at the R value of silicone composite insulators. The higher the R value the better the silicone composite insulators.
◆ Convection - Cold air blowing across you can of water and circular water currents in you can water. Maybe try wrapping your insulator in some plastic wrap. All types insulator can be done tests in this way, such as porcelain pin insulator.
◆ Radiation - Infrared radiation emitted from your hot water. Use a shiny metal to reflect the infrared radiation back toward the water. Some aluminum foil would be the cheapest method

Silicone composite insulators in service are subject to surface dirt to some degree, in all operating areas. Several types of contaminates can affect insulators performance. Proper maintenance procedures must be strictly followed to prevent damage to equipment. Composite pin insulator needs regular maintenance.

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