Stainless steel is a type of steel that is resistant to weak corrosive substances like air, steam, and water. It is also resistant to chemical substances like acids, alkalis, and salts. This type of steel is commonly known as stainless steel. On the other hand, there is another type of steel that is resistant to chemical substances but not necessarily to weak corrosive substances. This type of steel is called acid-resistant steel. The corrosion resistance of stainless steel depends on the specific alloying elements present in the steel.

Nickel alloys were created in the late 1930s. In 1941, Britain produced the first nickel-based alloy called Nimonic 75 (Ni-20Cr-0.4Ti), and later improved it by adding Al to enhance its creep strength, resulting in Nimonic 80 (Ni-20Cr-2.5Ti-1.3Al). The United States, Russia, and China also developed their own nickel-based alloys

Welded pipes have a wide range of applications in various industries and fields. Whether in the oil and gas industry, chemical industry, construction industry, or other industrial fields, welded pipe is a common choice. This is because welded pipes have many characteristics and advantages, making them an ideal option in these fields.