The Fiber Optic Splice Closure , also called the optical cable connector box and the barrel, is suitable for the straight-through and branch connection of the overhead, pipeline, direct burial and other laying methods of various structural optical cables. In the optical communication network, due to the limited length of the optical cable and the need for the optical cable to branch on the transmission line, the optical cable connector is generated, and the fiber optic splice closure provides conditions for the connection and branching of the optical cable and protects the connector. At present, the application of the fiber optic splice closure is very wide, but the insulation problem of the fiber optic splice closure has always been a major problem, and the dielectric properties and plasticity of the material itself are combined to make a suitable choice. Therefore, the structure and material of the insulation and the condition of the surface also have a great influence on the withstand voltage strength performance of the fiber optic splice closure. If you want to improve the withstand voltage performance of the fiber optic splice closure, you must use a better insulating material such as Teflon to increase the surface finish and reduce the curvature between the insulator and the pole and pole and between the pole and the ground. Insulating gaskets conventionally used in fiber optic splice closures generally consist of two upper and lower spacers. The upper gasket is a recessed gasket and the lower gasket is a convex gasket. Since the fixing bolt is connected to the reinforcing core of the communication cable, the upper and lower insulating spacers are combined to form an insulation between the metal member of the fiber optic splice closure and the cable reinforcing core (ie, the fixing bolt). In the compressive strength test, a DC voltage of 15 kV will be applied between the fixing bolt and the metal member. Most of the materials used for insulating gaskets are high molecular polymers. The main feature of this method is to improve the combination of the upper gasket and the lower gasket.