Most of the cling film rewinder use a conical top chuck to clamp the unwinding cling film roll.

     (1) Mechanically tighten the mandrel: the mandrel is a pipe with a lead screw in the middle, and the two threads of the lead screw have opposite directions. When the adjusting wire rotates, the upper nut moves in the uranium direction, and the chute surface of the nut moves the tension block out, so that the plastic wrap and the mandrel are tightened.

     (2) Air-expandable mandrel: pipes are used as the mandrel. There are many holes or long holes evenly distributed in the length of the cling film roll on the main body of the tube. The holes are equipped with correspondingly shaped tension blocks, and the bottom of the tension block is fixed. There is a spring support plate, and there is an elastic air cavity in the inner hole of the tube. When compressed air is filled in the air amine, the air cavity expands the expansion block through the support plate to push out the tension block, forming a convex surface, which can roll the core of the cling film department is stuck tightly.