Brass is a copper alloy with zinc as the main additive element. It has a beautiful yellow color and is collectively called brass. The copper-zinc binary alloy is called ordinary brass or simple brass. Brass with more than three yuan is called special brass or complex brass. Brass alloys containing less than 36% zinc are composed of solid solution and have good cold workability. For example, brass containing 30% zinc is commonly used to make bullet casings, commonly known as cartridge brass or seven-three brass. Brass alloys containing between 36 and 42% zinc are composed of solid solution, the most common of which is 40% brass with 40% zinc. In order to improve the performance of ordinary brass, other elements such as aluminum, nickel, manganese, tin, silicon, lead, etc. are often added.　　
 
Aluminum can improve the strength, hardness and corrosion resistance of brass, but it reduces the plasticity and is suitable for seawater condensing pipes and other corrosion resistant parts. Tin can improve the strength of brass and its resistance to seawater. It is called naval brass and is used as a ship thermal equipment and propeller. Lead can improve the cutting performance of brass; this free-cutting brass is often used as a watch part. Brass castings are commonly used to make valves and pipe fittings. The fire hydrant explosion-proof crescent wrench commonly used in ships is cast from brass and aluminum.　　
 
Hebei Outong Nonferrous Metal Products Co., Ltd. was founded in 1999 with a registered capital of 50 million yuan, covers an area of ​​170,000 square meters, and has more than 300 employees. After more than ten years of development, the company has grown in size, with special-shaped copper tubes, copper rods and copper tubes. It has built a modern large-scale private enterprise group integrating research, development, smelting, finishing, testing and sales of non-ferrous metals. Outong people have been adhering to the business development concept of "innovation, integrity, service", and taking the responsibility of creating a world-class brand, and constantly improving the quality of products. It has been listed as "Top Ten Private Enterprises" and "Consumer Trustworthy" by the provincial and municipal governments for many years. enterprise".