PURPOSE: To prevent the thermal deformation of a winding roll and the occurrence of trouble such as the breaking of a steel strip wound on the roll by cutting plural grooves in the inside of the roll in the axial direction and sealing a specified molten metal in the space in the roll so as to form a heat pipe roll.
CONSTITUTION: Plural grooves 21 are cut in the inside of a roll in the axial direction, a liq. alkali metal 22 such as Na, K or Li is sealed in the space in the roll by 1W10% of the volume of the space and the resulting heat pipe roll is placed as a winding roll 4 for a steel strip in the vacuum deposition part of a continuous vacuum deposition apparatus. When the steel strip having a vacuum deposited film is wound on the roll 4 and transferred by the rotation of the roll 4, heaters 5 are set at the outside of the roll 4 to heat the strip. The part of the surface of the roll 4 kept in contact with the strip is slightly heated and the remaining part kept in noncontact with the strip is heated to a high temp., producing a temp. difference by which the roll is thermally deformed. The temp. of the roll 4 is, however, made uniform by the movement of the molten metal 22 in the roll to prevent the bending of the roll due to thermal deformation and the breaking of the strip.