COLO coating engineers recommended to note the following:
(1)pre-treatment is not completely washed residue on the workpiece caused byadhesion degreaser, phosphate slag or alkaline wash tank pollution caused bythe difference. The solution is to strengthen the water, adjusting the processparameters and to prevent washing degreasing degreasing fluid into phosphateafter slot.
(2) phosphate coating yellowing, adhesion or no local flooding caused by poor phosphate coating. The solution is to adjust the concentration and ratio of phosphate bath, improve phosphatetemperature.
(3)Workpiece corners without a net drying moisture caused poor adhesion. The solution is toincrease the drying temperature
(4) a large area coating curing temperature caused by poor adhesion is not enough.The solution is to increase the curing temperature
(5) the amount of water, oil, salt adhesion caused by excessive differences. Thesolution is to increase the water filter, using water as the last two wash water.