1. Appearance
The external surface of faucet is usually chromium plated. The coating of the product has the specified technological requirements, and after a certain period of salt spray test, there is no corrosion within the specified time limit. In the case of sufficient light, the product can be placed in the hand and observed at an extended distance. The surface of the tap should be black and bright like a mirror, without any oxidation spots or burning marks; while there are no air holes, bubbles or leaks in the near view, and the color is uniform; no burrs or sand grains can be touched with the hand; when the finger is pressed on the surface of the tap, the fingerprints will disperse quickly, and it is not easy to adhere to scale. Some faucets are coated with titanium, bronze (imitation gold) and gold-imitation electrophoretic paint. Electrophoretic paint or bronze-plated faucets are often corroded very quickly, which is difficult for non-professionals to identify, but the general quality assurance card will indicate the relevant requirements on the faucet surface.
2. Materials
The main parts of the faucet shell are usually cast with brass material, which is treated by sand cleaning, turning, pickling and infiltration, pressure testing, polishing and electroplating. Some manufacturers choose zinc alloys instead to reduce production costs. Handles, decorative nuts, triple bathtub faucet conversion valves are basically made of brass, zinc alloy, ABS engineering plastics; wall covers are made of copper, stainless steel and plastics; connecting nuts and eccentric joints, brass for water outlet shell. Brass material is recommended for the above components. The electroplating quality of products made of brass can be guaranteed with long corrosion resistance. The higher the purity of brass, the better the quality of electroplating, the less easy the surface electroplating corrosion. Zinc alloy electroplating quality is poor, corrosion resistance is not good, but the ABS engineering plastics is the cheapest and the quality of electroplating is poor. It can be identified by weight estimation, secondary surface scratches and surface electroplating quality. Brass is heavier and harder, zinc alloy is lighter and softer, plastic is lightest and softest. However, the state stipulates that zinc alloy materials are not allowed to be used for components directly in contact with drinking water.
3. Function
The faucet has various styles and functions. According to its usage, it can be used for washing basin, kitchen sink, bathtub, shower and body cleaner. According to the function, there are general, induction, constant temperature and so on. For example, the induction faucet has the function of automatic induction water outlet, which is convenient, sanitary and more suitable for public places (high-grade) toilets.
4. Valve spool
The spool is the heart of the tap, and the ceramic spool is the best spool. The products with better quality are all made of ceramic spool, which has the characteristics of strong wear resistance and good sealing, and can generally be used more than 300,000 to 500,000 times. Low-grade products mostly use copper, rubber and other seals, which have short service life but low price.
5. Surface
Faucet should pay attention to the gloss of the surface, no burr, no stomata, no oxidation spots and so on are preferred when touching. The main body of high-quality faucet is generally made of copper. After forming, grinding and polishing, the surface of faucet is plated with copper, nickel and chromium (three-layer electroplating). Common products are only plated with nickel and chromium (two-layer electroplating). The plating of regular products has specific technological requirements, and through neutral salt spray test, there is no rust phenomenon within the prescribed time limit. Therefore, the high-quality faucet products have compact structure, uniform coating, smooth and delicate color, lasting for a long time.
6. Handle
Turn the handle gently to see if it is light and flexible, whether there is blockage, check the faucet parts, especially the main parts assembly is tight, should not feel loose.