aluminum window screen

With the improvement of people’s living standards now, many families are keeping some small pets, these small pets also need a stable nest, pet cage has become a more important choice of people, each pet habits and living habits will choose to adapt to the cage.

If the zinc coating is good, but in 3% nitric acid when the light, the coating has dark shadow, passivation occurs when the film is brown, may be caused by foreign metal impurities such as copper or lead in the galvanizing liquid. When problems occur in the process of galvanizing large coil galvanized wire, the temperature and current density are checked first, and then the content of zinc and sodium hydroxide in the plating solution is measured and adjusted through the analysis of the plating solution. Whether DPE content is low can be determined by hull cell test.