High-voltage line pin-type porcelain insulators are used for power frequency voltage 6~20KV high-voltage power lines for insulation and support of wires. The old models of insulators are based on voltages of 6, 10, 15, 20KV, each of which is divided into steel feet. It is available in two types: iron straight leg and wooden straight leg. The rated voltage of the new model is 10KV, which is divided into three types: ordinary type, reinforced insulation type 1 and reinforced insulation type 2.
The insulator is made of porcelain pieces, steel feet (or screw sleeves) with Portland cement and quartz sand glue not less than 525. The steel feet are glued into the porcelain parts to have deep grooves to prevent the steel feet from loosening. There is an elastic pad between the top of the steel foot and the porcelain piece. The surface of the porcelain piece is generally brown glazed, and the steel foot is hot-dip galvanized.
P-pin insulator, the number after the dash indicates the rated voltage (kV)，M-wooden straight leg，T-iron arm straight leg