The weld recoating process in the canning process has always been one of the weak links in the anti-corrosion processing of tinplate food cans. Many corrosions first attack the welds of food cans and then spread. Due to the short drying oven and fast processing speed, the recoating process requires that the recoating agent must be able to dry and solidify quickly and have good acid and sulfur resistance. In order to ensure the quality of recoating, cost saving must not be emphasized unilaterally when purchasing recoating materials.
When the drying oven performance is not good, the canning speed can be appropriately reduced to ensure that the recoating paint is dry. At the same time, pay attention to whether the wettability of the recoating paint and the inner coating is good, and check the recoating quality at any time. In order to solve the shortcomings of the recoating process, many canning manufacturers also use the full spraying process on the basis of recoating, so that while improving the recoating quality, it also makes up for the defects such as mechanical damage and burns caused by tinplate canning, greatly improving the anti-corrosion ability of food cans.
One point that requires special attention is that tinplate packaging cans containing alcoholic substances (such as liquor) are particularly prone to corrosion problems at the weld recoating. If you are not very sure about the quality of your factory's recoating, you should be very cautious when accepting orders.
