wide ironing board cover_ironing board cover 122 x 45

If the zinc coating is good, but when the light comes out in 3% nitric acid, there is a dark shadow on the coating, and the film is brown when passivation occurs, which may be caused by foreign metal impurities such as copper or lead in the galvanized liquid. When there is a problem in the process of galvanizing, check the temperature and current density first, and then measure and adjust the content of zinc and sodium hydroxide in the bath through the analysis of the bath. Whether DPE levels are low can be determined by Hull cell test.

Annealing wire is widely used because it has a good elasticity and flexibility, in the annealing process can be good control of its hardness, it is mainly made of iron wire, more often used in the construction industry binding wire use. In the production of the wire factory, annealing wire will be processed according to the properties of the material, according to the needs of different to change its hardness degree, can make it has more advantages, can reduce the consumption of metal, reduce the cost of production.