According to analysis on telescoped coil produced during coiling process of hot galvanized strip
it is obtained that the unmatched coiling tension and the slip of mandrel in sleeve are main causes to bring about telescoped coil defect. To revamp the mandrel of coiling tension reel
use the coiling model of constant tension control combined constant torque control
and optimize the coiling tension are available to avoid the formation of telescoped coil of hot galvanized strip.