Origin of cold forging development

Cold die forging, cold extrusion, cold heading and other plastic processing. The cold forging of die manufacturers is the forming process below the recrystallization temperature of materials and the forging process below the recovery temperature. In production, it is customary to call forging without heating blank cold forging. Cold forging materials are mostly aluminum and some alloys, copper and some alloys, low carbon steel, medium carbon steel and low alloy structural steel with low deformation resistance and good plasticity at room temperature. Cold forging has good surface quality and high dimensional accuracy, which can replace some cutting. Cold forging can strengthen metal and improve the strength of parts.

Modern cold forging technology began at the end of the 18th century. Since the French in the French Revolution era squeezed lead out of small holes to make bullets, extrusion has become a new term and a new technology.

In 1830, France began to reverse extrude lead pipes and tin pipes with a mechanical press.

In 1886, the hollow bottomed bullet case of injection molding appeared in France. The above are all hot forging and hot pressing, but they are the basis of cold forging.

In 1900, L.E. Hooker of the United States obtained the forward extrusion method for hollow pieces of nonferrous metal materials such as lead, zinc, aluminum and brass, and manufactured brass suit buttons. During the First World War, the United States made brass cartridge cases by forward extrusion, and Germany developed steel cartridge cases.

In 1935, the Germans used the phosphating treatment method and new lubricant developed in the previous year to produce steel bullets by extrusion, which became a military secret during World War II.

In 1940, the cold extrusion of steel shell and cylinder parts appeared, and China and other countries began to introduce from foreign countries in the early 1950s, which was first applied to cold forging of bicycle parts. Later, cold forging entered the production industry of motorcycles and textile machinery. In the 1960s, it entered the automotive industry, electrical industry and other fields. Since the 1980s, important achievements have been made in the application and research of Japanese cold forging technology in the processing of high-precision and complex shaped parts, which are used in some composite materials, equipment manufacturing and automotive components.

In 2002, Guangdong, Zhejiang, Shanghai, Jiangsu and other places in China used this equipment to forge lamps, automobile pipe fittings, and generator covers. With the diffusion of the technology, it was circulated by the vast manufacturing industry.