Process management of coating line

The process flow of the coating line is divided into: pretreatment, powder spray coating, and heating and curing. To manage this process, you need to pay attention to the following points:

(1) Production management of the pretreatment section of the coating line

Painting line process

The pre-treatment has manual simple process and automatic pre-treatment process, the latter is divided into automatic spraying and automatic immersion spraying two kinds of processes. The workpiece must be surface treated to remove oil and rust before powder spraying. There are a lot of chemicals used in this section, mainly including rust remover, oil remover, surface adjustment agent, phosphating agent and so on.

In the pre-treatment section or workshop of the coating production line, the first thing that di should pay attention to is to formulate the necessary strong acid and strong alkali purchase, transportation, storage and use systems, provide workers with the necessary protective clothing, safe and reliable clothing, handling, equipment, and Formulate emergency measures and rescue methods in case of accidents. Secondly, in the pre-treatment section of the coating production line, due to the existence of a certain amount of waste gas, waste liquid and other three wastes, in terms of environmental protection measures, it is necessary to configure air extraction and exhaust, liquid drainage and three waste treatment devices.

The quality of the pre-treated workpieces, because the pre-treatment liquid and the process flow of the coating production line are not the same, the quality should be different. For the well-treated workpieces, the surface oil and rust will be removed. In order to prevent rusting again in a short period of time, phosphating or passivation should generally be carried out in the following steps of pre-treatment: before powder spraying, the phosphate should also be treated. The modified workpiece is dried to remove the surface moisture. Small batches of single-piece production are generally air-dried, sun-dried, and air-dried. For mass flow operations, low-temperature drying is generally adopted, using an oven or a drying tunnel.

(2) Organizational production of powder spray coating

For small batches of workpieces, manual powder spraying devices are generally adopted, while for large batches of workpieces, manual or automatic powder spraying devices are generally used. Whether it is manual powder spraying or automatic powder spraying, it is very important to control the quality. It is necessary to ensure that the workpiece to be sprayed is evenly powdered and has a uniform thickness to prevent defects such as thin spray, missed spray, and rub off.

In the process of coating production line, attention should also be paid to the hook part of the workpiece. Before curing, the powder attached to it should be blown off as much as possible to prevent the excess powder on the hook from solidifying. In case of difficulty, the cured powder film on the hook should be peeled off in time to ensure that the hook conducts well, so that the next batch of workpieces is easy to powder.

(3) Production management of curing process of coating line

The matters needing attention in this process are as follows: If the sprayed workpiece is produced in a small batch, please pay attention to prevent the powder from falling off before entering the curing furnace. If there is any phenomenon of powder rubbing, it should be sprayed with powder in time. Strictly control the process, temperature and time during baking, and pay attention to prevent the color difference, over-bake or too short time causing insufficient curing.

For workpieces that are automatically conveyed in large quantities, check carefully before entering the drying tunnel for leakage, thinning, or partial powder rubbing. If unqualified parts are found, they should be shut down to prevent entering the drying tunnel, and respray should be removed as much as possible. If individual workpieces are unqualified due to thin spraying, they can be sprayed and cured again after curing out of the drying tunnel.