With the rapid development of various industries, the optical cable communication system certainly does not allow much, and it is also developing rapidly. Among them, the fiber closure is the most developed. The development of fiber closures is very rapid, the use range is wider and wider, and the application fields are more and more.

The transmission loss of the fiber closure is closely related to the waterproof performance. Therefore, the fiber closure should have good air-tightness and waterproof performance. Generally, it is required to effectively waterproof, moisture-proof and prevent harmful gas intrusion within 20 years. The fiber closure must have a certain mechanical strength to ensure that the performance of the fiber is not affected when the pressure applied to the cable connection reaches 70% of its strength.

Long-term corrosion resistance of fiber closure: At present, the outer casing of most fiber closures is made of plastic products. In addition to corrosion resistance, the aging resistance and insulation performance of materials should meet the life expectancy of 20 years. The fiber closure should be easy to remove and the material can be reused. The fiber closure should be as light as possible to reduce the labor intensity during the connection and shorten the operation time.

The length of use of the fiber closure depends directly on the quality of the insulation material. Reasonable and strong insulation material is the fundamental guarantee for high voltage DC breakdown. Therefore, the structure and material of the insulation and the surface condition have a great influence on the withstand voltage strength performance of the fiber closure. In order to improve the withstand voltage performance of the fiber closure, it is necessary to use a better insulating material to increase the surface finish and reduce the curvature between the insulator and the pole and pole and between the pole and the ground. In the case where all other parameters are the same, this case can be increased by at least 100% in length.