A faucet, also known as a faucet, is one of the most widely used and widely used tools for washing and washing water. With the improvement of people&s living standards, the continuous improvement of housing conditions and daily equipment, the demand for water faucets is increasing, and the quality requirements for the outer coating of water faucets are also high. In response to the quality problem of water faucet electroplating, we will now improve the electroplating quality of water faucets, and briefly discuss the following issues.

1. Selection of raw materials

The quality of water nozzle electroplating not only depends on the electroplating process, but also involves various aspects such as water nozzle substrate material, casting process, electroplating pre-treatment, etc. The valve body of the faucet is the primary component, made of cast brass. The valve body, handle, and cover of a good faucet are all made of refined brass, which is cast, processed, polished, and then electroplated with nickel, decorative chromium, or chromium nickel alloy. If these products are well treated before casting, electroplating, and electroplating processes, they are generally more corrosion-resistant. In order to enhance the corrosion resistance of the product and improve its level, a multi-layer nickel plating process is also selected. However, some companies, in order to save production costs, add a lot of waste copper to the cast brass, making it contain a lot of impurities. This makes the product loose on the surface, containing a lot of sand holes, and not resistant to corrosion. After acid salt spray testing, it shows pitting and pitting corrosion. Some manufacturers even use selected cast iron and zinc alloy as raw materials because cast iron is prone to rust and zinc alloy is not corrosion-resistant. Water nozzles made from these materials are prone to rust spots. After 2 hours of acid salt spray testing, the valve body shows many defects such as rust spots and pitting. Some manufacturers use brass material for their faucet valve bodies, while the handle and valve cover use inferior materials such as cast iron and plastic. After 24 hours of acid salt spray testing, this type of product often shows that the valve body does not corrode, while the handle and valve cover exhibit severe corrosion, resulting in unqualified products and a decrease in product quality.

2. Casting process

The valve body of a water nozzle is the primary component, and its production method generally uses sand casting and metal casting. Due to the high quality requirements for the appearance of the faucet, there should be no visible pores, cracks, looseness, or inclusions on the outer surface of the casting before electroplating; The water nozzle body made of metal mold casting has a dense arrangement, good external quality, high yield, and may also prevent environmental pollution caused by sand mold casting. Therefore, most manufacturers currently use metal mold casting technology. However, when using a metal mold casting water nozzle valve, its outer surface is formed by a metal mold, and the inner cavity is formed by a coated sand core. When the copper liquid is poured into the metal mold cavity, the cooling rate of the outer surface is faster, and the casting arrangement is dense; The inner cavity is surrounded by a sand core, resulting in a slower cooling rate and a higher risk of shrinkage and loosening. Although some manufacturers choose cast brass with better raw materials, after 24 hours of acid salt spray test, the valve body still shows loss of gloss and rust spots. The reason is that the casting process of the water nozzle body was not well handled. So, as long as we strengthen the design of casting molds, the melting and pouring of alloys, the control of casting processes, and the sorting of sand drop, we can cast qualified water nozzle body castings.

3. Pre plating polishing and cleaning of qualified nozzle castings require mechanical processing, polishing, and polishing processes before electroplating.

Machining and polishing are the shaping and polishing of products. Polishing and polishing primarily flatten the surface of the product, reduce the roughness of the casting, and can also result in minor defects such as sand holes and burrs that may occur during casting. Because the appearance quality requirements of the water nozzle are relatively high, the coating on the outer surface of the water nozzle should be excellent, arranged finely, lubricated evenly, and the color should be uniform. The polished outer surface should be bright, without appearance defects such as bubbles, burning, detachment, and scratches. Polishing quality is a key factor in ensuring electroplating quality, improving surface brightness and defects. Water spouts are decorative products. Very sensitive to inclusions and debris, even extremely fine impurities may form defects such as burrs, pitting, or pinholes on the electroplating surface, and even result in coating burning, foaming, and peeling. If the 24-hour acidic salt spray test is conducted, it will show loss of light and rust spots, as well as bubbling and comprehensive corrosion, which have been treated very important. The sand and carbonized resin in the inner cavity after casting, the oil, copper shavings, and copper powder left after machining, and the polishing paste and other pollutants after polishing are all cleaned to ensure the quality of electroplating. The presence of pollutants is the primary factor causing burrs and pitting in electroplating.

4. Control of electroplating process

The appearance of the faucet is primarily electroplated with nickel chromium. The nickel chromium electroplating process has a history of many years. The electroplating process is very mature, with high purity of chemical raw materials and additives and few impurities; Moreover, the electroplating equipment is advanced, and during the electroplating process, as long as strict process management is carried out to maintain the cleanliness of the tank solution, rinsing water, equipment, and production environment, there are generally fewer electroplating quality problems. The corrosion resistance phenomenon discovered during testing is mainly due to some manufacturers reducing costs, electroplating time, and coating thickness, which cannot compensate for the fine pores of the coating. The corrosion solution corrodes the substrate through the fine pores, presenting many rust spots.

5. Conclusion

1) The valve body, handle, and cover of the faucet should be made of high-quality cast brass or copper alloy, and materials such as cast iron that is prone to rust and zinc alloy that is not corrosion-resistant should be discarded;

2) Choose metal mold casting for the water nozzle valve body and attach importance to the casting process;

3) Polishing and polishing are necessary, with proper pre-treatment before plating;

4) Strictly implement the electroplating nickel chromium process standards, strengthen process management, and ensure coating thickness.

The article originates from Kaiping faucet: http://www.clasito.net/