Process for plating cadmium on shaped steel part with deep/blind hole

Abstract

The invention discloses a process for plating cadmium on a shaped steel part with a deep / blind hole, which comprises the following steps of: chemical oil removal, electrolytic oil removal, hot water washing, cold water washing, acid washing, cold water washing, neutralizing, cold water washing, cyanogen-less cadmium plating, cold water washing, hot water washing, compressed air drying, tempering dehydrogenizing, bright dipping, cold water washing, surface conditioning, middle-temperature phosphating, cold water washing, drying and detection, wherein the formula of each liter of electroplating liquid comprises: 40 to 50g of cadmium sulfate, 180 to 220g of ammonium chloride, 50 to 70g of nitrilotriacetic acid, 25 to 30g of ethylene diamine tetraacetic acid, a main additive, a brightener and a refiner, and the pH value is 6.2 to 6.7. The process effectively improves the quality and stability of special products, guarantees the use performance of the products and prolongs the service life of the products; and the production process is clean and environmentally-friendly, can effectively protect the environment and the physical and metal health of operators and meets the requirements of pollution-free production.

Description

Technical field [0001] The invention relates to a surface treatment method and equipment for metal products, in particular to a process for plating cadmium on special-shaped steel parts with deep / blind holes, in particular to a cyanide-free cadmium plating suitable for large-scale production, clean and environmentally friendly Craft. Background technique [0002] In the past, the surface anti-corrosion treatment of special-shaped workpieces with deep holes and blind holes has always been cyanide electroplating due to its complex shape, high performance requirements, and harsh use environment. But cyanide is a highly toxic chemical, and it is quite complicated to purchase, transport, store, and manage. The gas that escapes during the cyanide electroplating production process is also toxic, and the treatment of cyanide wastewater requires extremely high safety and ventilation. In order to eliminate the harm caused by highly toxic cyanide and effectively protect the environment an...

AI Technical Summary

Problems solved by technology

[0003] Cadmium plating is generally used in special industries such as aviation and military industry. At present, most manufacturers use the cyanide cadmium plating process, and only a few of them use the general cyanide-free cadmium plating process. Difficult to control and maintain, narrow range of current density, poor deep plating and covering ability, dark, rough and hairy plating, etc.

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