The manufacturer of hot-dip galvanized flange nuts shall explain the reasons why flange nuts are sti

Time:2021-12-21

　　The manufacturer of hot-dip galvanized flange nuts shall explain the reasons why flange nuts are still used for defects

　　Along with the great development of Chinese electric power and traffic, it will promote the development of flange nuts hot dip zinc; Therefore, it is of great significance to develop automatic centrifugal pressure dump equipment, improve the hot dip zinc technology of fasteners and improve the quality of hot dip zinc coating of fasteners. Hot-dip galvanized fasteners have many defects because of their thick coating, high bonding strength and long time corrosion. It has been valued in the power, communication and transportation sectors. The following explains why hot dip galvanizing has defects but is still popular:

　　It is difficult to screw the thread after plating. After hot dip galvanizing, the remaining zinc is not easy to remove on the thread, and the uneven thickness of the zinc layer affects the fit of the thread. Technical requirements for hot dip galvanizing layer for steel products covered with metal; General technical requirements for electric power fixtures; The external threads of fasteners shall be machined or rolled in accordance with the method specified in the GB196 standard before or before hot dip plating, while the internal threads may be machined before and after hot dip plating. But in practical application, customers often require both internal and external threads to be galvanized, so people adopt various measures to solve the problem of hot-dip galvanized thread mating parts. For example, thread parts after the coating back attack; Set aside a large fit gap; Centrifugal casting and other methods. Thread is easy to damage part of the coating, even bare steel base, resulting in fastener rust. Deliberately increase the nut aperture or leave a fit gap, it is easy to reduce the fit strength, high strength of the fit is not allowed.

　　Hot dip galvanizing operation temperature is too high, will reduce the mechanical strength of high strength flange mother. After hot dip galvanizing, the strength of some threads of the 8.8 bolts is lower than the standard requirements; After hot dip galvanizing, the strength of the bolts above grade 9.8 can not meet the standard requirements. The working environment is bad, and the pollution is serious. The hot dip galvanizing process of fasteners is carried out at high temperature. The solvent drying in the zinc tank and the workpiece to be plated in the zinc leaching process will produce strongly stimulating hydrogen recording gas. The zinc tank is at high temperature for a long time, and zinc vapor is generated on the surface of the zinc tank.