(A) the smaller the resistance of the coating, the greater the resistance film deposition, the better throwing power. Good throwing power electrophoretic paint coated to ensure that the joints are welded, deep hole and the inner surface of the paint evenly, making the film to enhance corrosion resistance. It is proportional to the electrophoresis voltage, time and coating solids; and pH of the coating, the temperature and pole spacing is inversely proportional. Throwing power measurement method has glass and steel pipe method. When measured, the glass tube is inserted in the measuring device (or stainless steel tube) in the strip, after electrophoretic coating, remove the test strip, after drying, measure the electrophoretic paint height (in centimeters) on the strip, the strip electrophoresis paint height higher, indicating greater throwing power. Electrophoretic paint steel measuring method is suitable for high throwing power.
(B) protect and electrochemical plating, that macroscopic dispersion capacity (macrothrowing power). Bath so that the whole surface of the coating thickness uniformity capabilities plating. Many influential factors, mainly conductivity of the electrolyte, the degree of polarization of the electrodes, the resistive film on the electrode surface (including adsorption resistive film, an oxide film, the corrosion product film, fouling layer, coatings and other coverings), is protected and the complexity of the distribution of the auxiliary electrode equipment structure and the like. Research dispersion capacity, to prevent the occurrence of the phenomenon of the current shelter is extremely important. The measurement method is distributed in accordance with the fact that there is a certain bias during the initial plating metal on the cathode of the actual distribution of the current design.

I. Purpose: To determine the electrophoretic paint throwing power, and compliance with applicable HG 2-1048-77 (1985) standards.


Second, the main configurations: paint tank, glass and other components of the cathode and devices, tinplate test plate.


Third, the environmental requirements: Operating temperature: 15 ℃ ~ 26 ℃; Relative Humidity: 20% to 80%, without condensation.


Fourth, the system basic requirements:


  1, the inner diameter of the paint tank high (60 ± 3) mm, height (380 ± 3) mm glass cylinder at high 300mm marked with ticks, the top slot with a rubber stopper; the center is equipped with a rubber stopper inside diameter (17 ± 0.2) mm, length (400 ± 1) mm glass tube;


  3, tube length (400 ± 1) mm, the lower end of the glass tube from the bottom (20 ± 0.5) mm, the rubber stopper should be opened with a thermometer jack and wire leads hole;


  4, the cathode: High 48 ± 1mm, slightly smaller than the outside diameter of the inner diameter of the upper and lower bottomless trough paint tin cylinder, fixed adherent paint tank, 300mm tick off the cathode aligned with the slot and wire leads;


  5, the test plate: 420mm × (16 ± 0.2) mm × (0.2 ~ 0.3) mm tin plate.