1、 Anti rust coating process of construction machinery
Anti rust coating process of construction machinery can generally be divided into pre coating, surface treatment process and anti rust, primer and primer coating process.
1: Surface treatment of steel shot and steel sand
Surface treatment is one of the important processes of antirust coating. The quality of anti rust coating of construction machinery depends to a large extent on the way of surface treatment. The coating life is restricted by three factors: the surface treatment accounts for 60%, the coating construction accounts for 25%, and the coating quality accounts for 15%, according to British Imperial Chemical Company. The appearance of parts is handled differently. The construction machinery industry is different.
Increase the binding force between the antirust coating film and the metal substrate. Mechanical cleaning can effectively remove rust, welding slag, oxide skin on the workpiece and eliminate welding stress. Therefore, the rust prevention quality of construction machinery parts is greatly improved. The mechanical cleaning specification is required to reach ISO85011 ∶ 1988Sa2.5. The surface roughness shall reach 1/3 of the thickness of the antirust coating. The steel shot used for shot blasting shall meet the requirements of GB6484.
The surface treatment of sheet stamping parts is generally called chemical surface treatment. The process flow is:
Manual pretreatment → hot water washing → pre degreasing → degreasing → industrial water washing I → industrial water washing II → appearance adjustment → phosphating → industrial water washing III → industrial water washing IV → pure water washing I → pure water washing II → water pouring → drying
Or without pickling process, the above process can also be properly adjusted according to the oil and rust conditions of sheet stamping parts. Or do not use the pre degreasing process. Degreasing and phosphating are the key processes in the chemical treatment process of steel shot, which directly affect the quality of chemical treatment of workpiece and the quality of antirust coating. Relevant process parameters and relevant auxiliary equipment are also factors that can not be ignored to affect the quality of surface treatment.