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Original title: How to Improve the Technology of Hot-Dip Galvanized Bolts (1) Incomplete pre-treatment before hot-dip galvanizing. There is an oxide film on the surface of the workpiece, which hinders the proper deposition of zinc. (2) Poor conductivity. The current loss in the wires results in too little current being delivered to the surface of the workpiece. (3) The workpiece has a high carbon content. High-carbon steels, cast iron parts, etc., also lower the hydrogen evolution potential, accelerating hydrogen evolution on the surface of the workpiece and reducing current efficiency. (4) The workpieces are tied too tightly. During galvanizing, local areas of the workpiece were shielded, resulting in an overly thin coating. (5) The galvanizing temperature is too low. When the temperature for galvanizing is low, the current density applied decreases accordingly, and the deposition rate of the coating in hot-dip galvanizing processes also inevitably slows down. (6) The sodium hydroxide content is too high in galvanizing. A high content of sodium hydroxide results in a reduced current efficiency during hot-dip galvanizing. (7) The content of additives in galvanizing is low. A low content of additives can affect the dispersion ability, resulting in overly thin coatings in certain areas. (8) During hot-dip galvanizing, the area of the parts to be coated is underestimated, resulting in an excessively low current density applied during coating. (9) The workpiece is not hung properly; its position should be adjusted. (10) Excessive corrosion of the workpiece. Lowering the hydrogen evolution potential accelerates hydrogen evolution on the workpiece surface, reducing the current efficiency and thus affecting the zinc deposition rate. An appropriate amount of corrosion inhibitor should be added to the pickling solution; if the scale is too thick in certain areas, it should be removed mechanically first, and inspections should be carried out frequently during the pickling process. (11) Anode passivation. The effective area decreases, affecting the normal distribution of current. (12) The sodium hydroxide content is low. When the sodium hydroxide content is low, the current density cannot be increased, resulting in anode passivation. Secondly, several techniques for improving the quality of hot-dip galvanized bolts: (1) Common hot-dip galvanized bolts: The flux on the surface of the screw is in liquid form, and the screw is directly placed in a liquid at 600 degrees Celsius for hot-dip galvanizing. Using this method for galvanizing, the oil and dirt on the surface of the screws must first be removed by pickling; it is best to do this in a lead-free environment. This method is not originally suitable for bolts and similar fasteners. (2) Single batch of bolts: First, the oil and dirt on the surface of the bolts are removed through pickling, after which the bolts are placed in a water tank. When the galvanizing temperature in the furnace is appropriate, the bolts are put into the tank for galvanizing, followed by oiling and chromating treatments. The hot-dip galvanized bolts produced by this method are of much better quality than those made by wet galvanizing, and the technology used is also more advanced.