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.

Annealed wire is a soft iron wire made of low carbon steel cold drawing, heating, constant temperature, heat preservation and other processes. The composition of iron wire varies according to its use. It contains iron, cobalt, nickel, copper, carbon, zinc, and other elements. The hot metal billet rolled into 6.5mm thick steel bar is the wire rod, and then put it into the wire drawing device into a different diameter of the line, and gradually reduce the aperture of the wire tray, cooling, annealing, plating and other processing technology made of various specifications of iron wire.

Cold wire drawing is a kind of cold processing of metal. The raw material is wire rod, which is produced by peeling, galvanizing and other processes. Galvanized cold drawing is used more in building materials. Its testing standards are also different. The strength of cold drawing is relatively high. Because of the high strength of steel, it plays a very important role in construction. It saves the construction steel in building materials, and also reduces the cost of the project. It also plays a very important role in the structure of concrete.

There are two varieties of steel grid plate is pressure welded steel grid plate and pressure lock steel grid plate, in many people’s eyes, these two products belong to the same variety, in fact, there are still great differences between them in many places.

The lighting surface of each type of shed is designed to be curved, improving the Angle of the light surface, because the lighting surface is curved, no dust accumulation, good light transmittance, high temperature in the shed, after measurement, the average temperature in the shed is 3℃ higher than the traditional bamboo pole cement column shed, the yield is increased by 15~20%, and the harvest date is advanced. The formula is scientific, the surface does not absorb moisture, do not return halogen through modification technology and scientific production process, solve the greenhouse frame rod is easy to absorb moisture return halogen, poor water resistance and easy to change the shortcomings, so that the greenhouse steel pipe in the high temperature and high humidity environment, few drops, frost phenomenon, and reduce pests and diseases.

Due to the influence of production process or other factors, the zinc layer of galvanized wire products will be different to a certain extent, especially ordinary galvanized can not reach the beauty of electric galvanized, ordinary galvanized wire zinc layer is mainly for anticorrosion and corrosion prevention. Large volume galvanized wire products refers to the use of high quality low carbon steel, after drawing forming, pickling rust removal, high temperature annealing, hot dip galvanized, cooling and other processes, some galvanized wire products are made of iron wire galvanized.

There are three methods to detect the thickness of zinc layer of galvanized wire: weighing method, cross section microscopy method and magnetic method, among which the first two experiments will cause certain damage to galvanized wire, including the length of galvanized wire and the reduction of dosage. The general detection of galvanized wire galvanized layer is detected by magnetic method, which is also a more intuitive and convenient method. The standard of galvanized layer thickness is related to the wire diameter of galvanized wire. The larger the wire diameter of galvanized wire, the thicker the galvanized layer is. It is the thickness of galvanized layer and cast iron after centrifugal separation.

Domestic iron wire factory has been able to consume wire rope, radial low steel wire, umbrella steel wire, spring steel wire, bicycle saddle spring steel wire and other products. In the 1980s, hot – plated low carbon steel wire, fan net cover steel wire, carbon structure steel wire, bed steel wire and so on were also published. The elongation of wire is increased after annealing. Make the product more soft and increase the scope of application of the wire.