coil nails for fence pickets

The wire rod should be normalized or soxhlet processed, instead of spheroidal annealing for standard large ones. Soxhlet process is widely used in the heat treatment of the center, especially the products before drawing. Avoid decarbonization during heat treatment. After heat treatment, sulfuric acid or hydrochloric acid pickling is used to remove iron sheet. The coating (see smooth carrier) can be dip-lime, phosphating, borax treatment or copper plating.

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.