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The diameter of cold-drawn wire should conform to the contract, check whether the amount of zinc meets the requirements of the contract, check the tensile strength, and ask the factory to provide the corresponding inspection report. The wire factory introduces that the weight of a single coil of wire of different specifications should not be lower than the volume weight required by the contract, and record the value. No contacts are generated for each reel of wire. If there are contacts, no more than three contacts are generated for each reel. Each contact should be smooth surface treatment, the wire can not be pulled off from the contact, in line with customer packaging requirements.

Zinc is a silver-white metal, brittle at room temperature, soluble in acid can also be soluble in alkali, known as amphoteric metal. Pure zinc in dry air is more stable, in humid air or containing carbon dioxide and oxygen water is small, the surface will generate a layer of basic zinc carbonate based thin film layer, it can delay the corrosion rate of zinc layer. The corrosion resistance of zinc coating in aqueous solution of acid, alkali and sodium chloride is stronger.