PH extension ring belongs to connecting hardware in electric power fittings. It is generally used in combination with right angle hanging plate and other products. In the process of use, the tensile strength shall be in accordance with the national grid standard. PH type extension ring belongs to one of the universal connection fittings. The connection fittings are directly used to connect insulators, so the structural dimensions of the connection parts match with the insulators, such as ball head hanging ring, bowl head hanging plate, etc. According to the definition of GB/T5075-2001 Standard Terminology of Electric Power Fittings, electric power fittings are metal accessories that connect and combine various devices in the power system and play a role in transferring mechanical loads, electrical loads and some protection. PH extension ring is mainly used for connection between insulator string and hardware, between clamp and insulator string, and between lightning conductor and pole. 1. The extension ring belongs to the connection fittings in the power fittings. The extension rings produced by our company are all made of round steel forging, which are used for the connection of ring fittings to lengthen the connection size or change the connection direction. When isolating the tight line, the extension ring can also be used to solve the construction problem of over-traction. On non-linear towers, when the jumper between two strings of tensile insulators is insufficient for the clearance distance to the cross arm due to wind deflection, an extension ring can also be installed on the insulator string. When the dry-shaped tower is used for transposition, an extension ring is sometimes installed on the tensile insulator string to meet the requirements of the jumper for the gap between the tower and the tower. 2. The connecting fittings are used to form a string of suspended insulators and hang them on the tower. The connection between the suspension clamps for linear towers and the clamps for non-linear towers and the insulator strings is also assembled by connecting hardware. Others, such as the anchoring of the cable fittings of the cable tower and the tower, also use the connecting fittings.