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High-voltagelinepininsulatorsaremainlyusedtoinsulateandsupportwiresforhigh-voltageoverheadtransmissionandtransformationlines.Accordingtotheratedvoltage,itisdividedintofivegrades:6,10,15,20,35KV.ThepininsulatorismadeofItiscomposedofporcelainpartsandsteelfeet,andtheporcelainpartsandsteelfeetareintegratedwithPortlandcementglue.Thesurfaceoftheporcelainpieceiswhiteorbrown.Thesurfaceofthesteelfeetishot-dipgalvanized.