Carbon Steel Fittings: Carbon steel is the most widely used fitting material, characterized by low cost, high strength, and good machinability. Its surface is usually galvanized or painted to enhance corrosion resistance, making it suitable for general industrial pipelines, plumbing systems, and other applications. However, carbon steel is prone to rusting in humid or corrosive environments, requiring regular maintenance.
Stainless Steel Fittings: Stainless steel fittings (such as 304 and 316L) are renowned for their excellent corrosion resistance and hygienic properties, and are widely used in the food, pharmaceutical, and chemical industries. 304 stainless steel is suitable for general corrosive environments, while 316L, containing molybdenum, has stronger resistance to chloride ion corrosion, making it suitable for marine or high-salt-spray environments. Stainless steel fittings are more expensive, but have lower long-term operating costs.
Copper Fittings: Copper fittings have good electrical and thermal conductivity and corrosion resistance, and are commonly used in refrigeration, air conditioning, and plumbing systems. Pure copper fittings have good ductility but lower strength; brass (copper-zinc alloy) fittings have increased strength and hardness through the addition of zinc, making them suitable for medium- and low-pressure applications. The price of copper fittings is greatly affected by fluctuations in copper prices. Alloy steel fittings: Alloy steel fittings have their high-temperature and high-pressure resistance enhanced by the addition of elements such as chromium, molybdenum, and nickel. They are commonly used in high-pressure industrial fields such as oil, natural gas, and power. For example, A105N alloy steel fittings are suitable for low-temperature environments, while F91 alloy steel fittings can withstand temperatures above 600℃. Alloy steel fittings are more expensive, but offer superior performance.
Plastic fittings: Plastic fittings (such as PVC, PP, and PE) are lightweight, low-cost, and resistant to chemical corrosion, and are commonly used in agricultural irrigation and chemical pipelines. However, plastic fittings have poor temperature resistance and are generally suitable for low-temperature, low-pressure environments. Furthermore, they are prone to aging when exposed to ultraviolet light for extended periods.
