PURPOSE: To raise engagement strength of a can end plate and a can cover, and also to raise its tightly sealing property by executing wind-clamping by a ring-like chuck to the outside circumferential face of a rolling-in edge part of the can cover, and a rolling roll to the inside circumferential face of said rolling-in edge part, when sealing tightly the can cover to the can end plate.

CONSTITUTION: A chuck 9 is fitted to the outside circumferential face of a rolling-in edge part 3a of a can cover 3. Subsequently, when a torque lever 15 is rotated as shown by a virtual line by moving downward a rotary shaft 12, an inside rolling roll 19 is made eccentric by S0 from the shaft center together with a distance of a moving span S of the lever 15, and a roll shaft 17. As a result, the roll 19 is made to press-contact with the inside circumferential face of a rolling-in edge part 3a as shown by the virtual line, and when the shaft 12 is driven to rotate, the roll shaft 17 becomes eccentric through the lever 15 and executes a rotating motion. Accordingly, the roll 19 supported by the shaft 17 rolls along the inside circumferential face of the edge part 3a, the edge part 3a is sealed tightly to an edge part 2a of a can end plate 2, also caulk-working 3b is performed by a projecting line 19a of the roll 19, and it is wind- clamped firmly. In this regard, after wind-clamping is completed, when a rotation of the rotary shaft 12 is stopped, and subsequently, the shaft 12 is drawn up, the roll 19 is returned onto the shaft center again, and a can be detached.