1. Wheel coating process:

On a large domestic wheel production line, the wheel coating process is: loading, pre-degreasing (spraying), degreasing, water washing, water washing, pickling (hydrochloric acid), water washing, water washing, water washing, neutralization, water washing, surface conditioning, phosphating, water washing, water washing, water washing, pure water washing, pure water washing, cathode electrophoresis, 0 times UF washing, UF1 washing, UF2 washing, pure water washing, pure water washing, baking, unloading (transfer to hanging surface coating line). The whole line adopts continuous assembly line production, the immersion tank is a boat-shaped tank, and the pretreatment, electrophoresis, and drying are a circulating conveying system, that is, a common conveyor chain.

2. Common problems in coating

Blistering and rusting problems in wheel gaps: On the production line, the phosphate film in the wheel gaps, welds, etc. often rusts and the phosphate film is incomplete. After electrophoresis, the paint film bubbles or paint residue-like substances exist in the wheel gaps. In addition, after the wheels are placed outdoors for a long time after electrophoresis, yellow rust water sometimes flows out from the gaps between the wheels. In production, the smaller the gap between the wheels, the more likely this problem will occur.

1 Cause analysis: (1) Incomplete degreasing; (2) The influence of residual acid ions; (3) Phosphating:

2 Improvement measures: (1) Improve the degreasing effect; (2) Strengthen the water washing of the workpiece after degreasing