Double jointing is a canning process in which the canning ends (or caps) are mechanically linked to seal the canning.
Initially, when the can is full, the tank ends are welded or welded to the tank body. However, this has brought many problems, such as external pollutants (including lead and other harmful heavy metals). The double-seam was developed as a cheaper and safer alternative, and was soon replaced by welded seams.
A double-jointed mechanism has been fabricated using a double-jointed mechanism which may consist of only one or more heads or joint stations. By mechanically locking several layers of material together to form a double layer: a three-layer tank and a two-layer tank. Each joint head usually consists of two rollers, the first and second operating rollers, and a chuck. Some sewing machines have two first operating rollers and two second operating rollers, and some machines use the term ldquo; Orbital suture. The method does not require a roll.
During the joint operation, the end of the can is lowered onto the filled tank and pressed down by a chuck which ACTS as an anvil for the joint operation.
The first operating roller then makes the end of the tank against the tank joint, thus causing the end bend to fold around the flange of the tank. In some sealers this is done when the tank is rotating at high speed. In other sealing machines, the tank is fixed and the first operating roller (or rollers) are rotated several times to ensure that the first operation is completed. After completing the first operation, the first operating roller is detached from the tank and the second operating roller is engaged with the tank.
The purpose of the second operation is to iron the double slit into the final shape and remove the gap between the tank and the final material layer. In fact, without sealant, it is impossible to iron all cans and end materials in all crevices without leaving any gaps.