Auto electrophoresis coating line: Essentials of electrophoresis coating
2014/9/19 8:30:19 / Publish: The Station / Pageviews：
The electrophoretic painting line: electrophoresis coating Essentials
(1) electrophoresis coating usually metal appearance, its technological process is: pre finishing, on-line, degreasing, water washing, rust, water washing, neutralization, washing, water washing, phosphating, passivation, electrophoretic coating, groove washing, ultrafiltration water washing, drying, offline.
(2) is the substrate and pretreatment punishment punishment coated on the electrophoretic coating has great effect. Castings often take sand or shot peening derusting with cotton yarn held, clean the surface dust, 80# ~ 120# sandpaper to clean residual impurities such as shot appearance. Steel appearance take degreasing and derusting treatment penalty punishment, to the appearance of excessive demand, hold the phosphating and passivation surface treatment of punishment. Ferrous metal workpiece phosphating punishment punishment must be held in the anode electrophoresis paint film before, otherwise the poor performance of resisting corruption. Phosphating penalty punishment, as usual selection of zinc salt phosphating film, thickness of about 1 ~ 2 m, the requirements of phosphating film fine crystal symmetry.
(3) in the filtering system, often take a class filter, filter for bag type layout, the diameter of 25 to 75 M. Electrophoretic coating by vertical pump to filter filter. Consider from the factors of comprehensive change cycle and film quality, diameter of 50 mu m filter bags best, it not only meet the quality requirements of film, and the handling problem of blocking the filter bag.
(4) circulation circulation system of electrophoresis coating of size, directly affect the quality of the bath stability and coating. Increase the recycling amount, precipitation friendly bath bath bubble eliminated; but accelerated aging, energy depletion of growth, stability of bath solution variation. The number of cycles the bath control 6 ~ 8 times /h ideal, not only ensure the coating quality, and ensure the stability of the bath.
(5) along with the extension of production time, impedance anode diaphragm increases, the voltage effective landing things. Therefore, the production should be voltage according to voltage loss environment, things hang sudden high power supply, to compensate for the voltage drop of the anode diaphragm.
(6) concentration of ultrafiltration system control of impurity ions into the workpiece, the coating quality guarantee. This system is in operation should be careful, system after running should be continuous operation, it is strictly prohibited to intermittent operation, in order to prevent the ultrafiltration membrane litter. Litter after the resin and paint adhesion in ultrafiltration membrane, not thoroughly washed, will influence the emergency ultrafiltration membrane permeability and service life. Ultrafiltration membrane water rate with the running time is on the decline, be continuous 30 to wash things every 40 day, to ensure that the ultrafiltration dip and rinse required ultrafiltration water.
(7) electrophoresis coating method is used for the production process of a large number of pipeline. The update cycle of electrophoresis tank solution should be within 3 months. With an annual output of 300000 copies of rim electrophoresis production line as an example, the bath scientific management is very important, many parameters to bath regularly held detection, and according to the detection result of mediation and change of the bath at. Usually by the following parameters: frequency measurement bath liquid, electrophoresis ultrafiltrate and ultrafiltration washing liquid, Yin (Yang) polar liquid, lotion, washing liquid circulation deionized pH, solids content and conductivity once a day; pigment and binder ratio, laboratory organic solvent content, small cell test 2 times a week.
(8) handle on the film quality, should often check the homogeneity of film and film thickness, appearance should not have a pinhole, sagging, orange peel, wrinkles and other signs, regular inspection of coating adhesion, resistance to decay properties of physical and chemical indices. The inspection period in accordance with the manufacturer's inspection scale, often are required to test each batch.
