The role of garolite g7 is in the electrical equipment to the potential of different charged part of the isolated. Therefore, the insulation material should first have a high insulation resistance and compressive strength, and to avoid leakage, breakdown and other accidents. Second, the heat resistance is better, to avoid long-term overheating and aging deterioration; In addition, there should be good thermal conductivity, resistance to lightning and high mechanical strength and process processing and other characteristics. According to the above requirements, commonly used g10 fiberglass tube performance indicators are dielectric strength, tensile strength, specific gravity, expansion coefficient.