Cap and pin insulator TR4
Cap and pin insulator TR4 is used on electrical apparatus and has the function of insulating and support. Cap and pin insulator is one type of wet process porcelain high voltage insulator and TR4 is a common type of it.
Cap and pin insulator is usually composed of a porcelain unit or a stack of two or more units, assembled with cap and pin on it, the metal cap will be assembled with bolts, the metal parts are assembled with cement to the porcelain parts.
Orient Power is an insulator manufacturer of cap and pin insulator, we can manufacture many types high voltage equipment, the most common one is cap and pin insulator TR4, another one is TR1, and also TR7. Cap and pin insulator TR4 complied with two types of standard, one is IEC 60305 Class, and another type is ANSI C29.8 Class.
Cap and pin insulator TR4 has good attribute of aging resistance, and electrical erosion resistance. Additionally, it has high tensile and bending strength, high mechanical strength, and easy to install. It also has function of lightning protection.
Originally there is no electrical test requirement for cap and pin insulator on international standard, but later the ANSI C29 committee added this on the standard C29.8. It is different from line post and post type, it is puncture, electrical routine tests and puncture tests are required before delivery. You can see Orient insulator photo of testing on our cap and pin insulator TR4.
electrical puncture test on cap and pin insulator TR4 mechanical test on cap and pin insulator TR4
Following is the technical data about porcelain cap and pin insulator TR4:
Lightning impulse withstand dry / BIL :110 kV;
Low-frequency wet withstand :45 kV;
Low-frequency dry withstand :50 kV;
Critical impulse flashover pos. :125 kV;
Low-frequency puncture :115 kV;
Low-frequency dry flashover :85 kV;
Low-frequency wet flashover :55 kV;
Leakage (creepage) distance :12" (305 mm);
Dry arcing distance :7" (180 mm).