According to the water quality problem of electroplating, I read a lot of related materials, and acidic salt spray test on some products. We will improve the electroplating quality of faucet, on the following issues.

       1 material selection of faucets electroplating quality depends not only in electroplating process. Besides, it also relates to tap matrix material, casting and plating pretreatment etc. aspects. Faucet body is a tap main parts, the material is brass casting, the most common grade of ZCu40ZnPb2, casting wall thickness average is 3mm. A good faucet body, a handle, a valve cover all the brass refined, by casting, processing, surface grinding and polishing, nickel plating, decorative chromium or nickel chromium alloy, such products if in front of the casting, electroplating processing, electroplating process such as well, are generally more corrosion resistant. In order to enhance the corrosion resistance of the product and improve the grade of the product, the multilayer nickel plating process was adopted. But some enterprises in order to save the cost of production, in casting the incorporation of a lot of waste copper brass, making casting brass contains a lot of impurities, make such a product surface osteoporosis, contain more of trachoma, corrosion resistance, after acidic salt spray test appeared pitting and pitting phenomenon. Some manufacturers even use already out of the cast iron and zinc alloy as raw material, as iron rusts easily, zinc alloy corrosion resistance, faucets made from these raw material is prone to rust, after 2H acidic salt spray test body appear a lot of rust and pitting and other defects. Some manufacturers tap valve with brass, and handle and the valve cover the use of inferior materials of cast iron, plastic and so on, the product after 24h acidic salt spray test, often the body does not produce corrosion phenomenon, and the handle and the valve cover the more serious corrosion, resulting in products unqualified, the grade of the product is reduced.

        2 casting nozzle body is the main body of water, its production method generally used sand mold and metal mold. Due to the nozzle surface quality requirement is very high, so before plating the surface of casting can not have any visible pores, cracks, porosity and inclusion; the metal mold casting the faucet body is compact in structure, good surface quality, high rate of finished products, but also may avoid sand casting to the problem of environmental pollution. Therefore, the most manufacturers use metal type casting technology. But the metal mold casting nozzle valve, outer surface by metal molding cavity by coated sand core forming, when the copper liquid is poured into the cavity of the metal, surface cooling rate faster, casting microstructure compact; and the cavity in the sand core surrounded by, the cooling rate is slower, is easy to produce students shrinkage defects. Some manufacturers although the use of good material to cast brass. After 24h acidic salt spray test, body or loss of light and rust. The reason is the faucet body casting, casting process results. So, only strengthen the casting mold design, alloy melting and casting, casting process control and shakeout cleaning work, can cast out qualified faucet body castings.

         3 polishing and cleaning before plating
         Tap casting qualified through machining, grinding and polishing process in electroplating. Machined and polished is the product shaping, grinding and polishing of the product surface flattening, reduce the casting roughness, but also can eliminate the minor trachoma, burr and other defects produced by casting. Due to the relatively high requirements of the appearance quality of the nozzle and coating on the outer surface of the nozzle should be a good combination, the organization should be fine, smooth and uniform, uniform color, polished surface should be bright, should not have bubbles, burning, detachment, scratches and other surface defects. Polishing quality is the key factor to ensure the quality of plating, improve the surface brightness and eliminate the defect. The tap is decorative products. On inclusion and slag is very sensitive, even the tiny impurities, may also cause electroplating surface burr, pits or pinholes and defects, and even burned coating, blistering and peeling. Such as after 24h acidic salt spray test, there will be loss of light and rust, even on bubbling and comprehensive corrosion, so before treatment is very important. After casting the inner cavity of the sand and carbonization of resin, remaining after machining oil, copper scrap, copper powder, polishing the polishing ointment pollutants must be cleaned, so as to ensure quality electroplating. The presence of contaminants is a major factor in electroplating burrs and pits.

           4 control of electroplating process
          Water surface is mainly electroplating nickel chromium. And nickel plating chromium process has a history of many years, electroplating process is very mature, chemical raw material and chemical additive of high purity, less impurity; and electroplating equipment advanced, electroplating process as long as strict process management, keep bath, rinse water, equipment and production environment clean, seldom appear electroplating quality problems. Found in the detection of the corrosion phenomenon is mainly some manufacturers in order to reduce the cost, reduce the plating time, coating is thin, can not be completely compensate for coating the pore, liquid corrosion resistance through the pores into the matrix, a lot of rust.

          5 conclusions (1) the water faucet body, a handle and a valve cover to choose quality good cast brass or copper alloy, and get rid of rust of cast iron, corrosion resistance of zinc alloy material, and so on; (2) the metal mold casting, the faucet body, attention to foundry processes; (3) grinding and polishing to completely, good treatment before plating; (4) strict implementation of nickel plating chromium process norms, to strengthen the process management, ensure that the coating thickness.