Principles of tinplate coating（Continuous）
The side seam welding part of the tinplate can can not be coated with paint, otherwise the can body blank will easily penetrate the side seam during the high-frequency resistance welding process and cause waste cans. Therefore, the operator should make grooves on the blanket cylinder according to the coating area of the can. The paint is printed on the tinplate by a slotted rubber roller, and the blank iron left at the slotted part is the high-frequency resistance welding part of the empty can.
We have realized in actual operation that the size of the slot should be 1~2mm wider than the actual welding space, so that the printed space can meet the welding requirements of the empty tank.
The coated tinplate is transported to the drying room by conveyor belt, and is cured at high temperature through the drying room driven by the circulating chain. The drying room is generally divided into three parts: the first part is to preheat the iron sheet to the baking temperature; the second part is constant temperature baking; the third part is to fully cool the iron sheet. The whole baking time needs 10-15min. After that, an automatic plate unloading machine is used to remove the iron sheet, and the coating is transferred to the can-making process after inspection and physical and chemical tests are qualified.
