Seamless steel pipe is a circular, square, rectangular steel with a hollow section and no seams around it. Seamless steel pipes are made from steel ingots or solid tube blanks that are perforated into tubes, and then hot rolled, cold rolled, or cold drawn.
Seamless steel pipe production has a history of nearly 100 years. In 1885, the German Mannesmann brothers first invented a two roll cross rolling piercer, and in 1891, they invented a periodic pipe mill. In 1903, the Swiss R. C. Stiefel invented an automatic pipe mill (also known as a top type pipe mill). Later, various extension machines such as continuous pipe mills and pipe jacking machines emerged, beginning to form the modern seamless steel pipe industry. In the 1930s, due to the use of a three roll pipe mill.
Extruder and periodic cold rolling pipe mill have improved the variety and quality of steel pipes. In the 1960s, due to the improvement of continuous pipe rolling mills, the emergence of three roller piercing machines, especially the success of using tension reducing mills and continuous casting billets, improved production efficiency and enhanced the ability of seamless and welded pipe to compete.
In the 1970s, seamless and welded pipes were keeping abreast of each other, and the world’s steel pipe production was increasing at a rate of over 5% per year. After 1953, China attached great importance to the development of the seamless steel pipe industry, and has initially formed a production system for rolling various large, medium, and small pipes. Generally, copper pipes are also processed by cross rolling and piercing of ingots, rolling with a pipe mill, and drawing of coils.