Development of cold heading machine technology

Guide: Analysis of the development status and scale of cold heading machine technology at home and abroad. In 1982, Shanghai Institute of Standard Parts Company and Shanghai No. 3 Standard Parts Factory jointly designed and successfully manufactured 5Z41-24 5-station large material small deformation multi station automatic cold heading machine by Shanghai Standard Parts Machinery Factory, which reduced the material cracking rate from more than 15% to less than 5%. In 1988, Shanghai Standard Parts Co., Ltd. successfully organized the design and manufacture of ZM5-500 new type large material small deformation multi station automatic cold heading machine, which expanded the product specifications of high-strength nuts and promoted the development of special-shaped nuts.

1、 Technical development status of cold heading machine industry in China

Cold heading technology is a cold plastic constrained deformation technology in metal processing. It is an advanced production technology with high precision, high efficiency, high quality, low consumption, less cutting. Cold upsetting machine is a machine tool that uses cold upsetting technology to produce various standard parts, fasteners and special-shaped parts. With the development of modern industry and the increasingly fierce competition in the manufacturing industry, cold heading technology has been widely used in machinery, instruments, electrical appliances, light industry, aerospace, shipbuilding, military and other industrial sectors, and has become one of the indispensable and important processing methods in metal plastic bulk forming technology, due to its cost-effective process characteristics.

（1） Technical Development Status of Foreign Cold Heading Machine Industry

Multi station automatic cold heading machine, as an advanced forming equipment with automation, precision and high technology content, is widely used in various industries. At present, the cold heading machines produced by enterprises in Russia, Germany, Switzerland, the United States, Japan and other countries are at the leading level in the world. In particular, Germany used cold heading technology to make cartridges during World War II. Russia is also one of the earliest countries to study and apply cold heading technology. In 1935, the first screw forming thread rolling machine of combined cold heading machine was developed. Before the 1940s, West Germany produced a multi station automatic cold heading machine.

Today, the multi station automatic cold heading machine has achieved the integration of information control and cold heading oil mist post-processing.

National Machinery Company is now recognized as the pioneer in the design, development and manufacturing of cold forming equipment in the world. The recently developed FXP85XL cold heading machine has a forming force of 550 tons and a cutting diameter of 34 mm. The discharge length reaches 360mm.

With the rapid development of the domestic automobile industry, Japan's high-speed cold heading machine has also developed rapidly since the 1960s. The world's largest long rod cold heading machine, M1-120, newly launched by Sakura Machinery Co., Ltd., has a diameter of 38mm, a maximum processing length of 430mm, and a machine weight of 100t.

The maximum diameter of forming parts of BKA series of Swiss HATEBUR metal cold heading forming machine Φ 28- Φ 64mm, cutting diameter Φ 14- Φ 36mm, the maximum production rate is 150 pieces/minute.

（2） Technical Development Status of Foreign Cold Heading Machine Industry

In the late 1960s, the research and development of multi station automatic cold heading machine began in China. In 1968, Shanghai No.5 Nut Factory designed and manufactured the first vertical M4 nut multi station automatic cold heading machine in China. In 1969, Shanghai Standard Parts Company successfully organized the design and manufacture of the first Z47-12 multi station automatic cold heading machine for bolts in China. The production efficiency was increased by more than 6 times, and the material utilization rate reached about 90%. Since 1980, the multi station automatic cold heading machine has developed towards the direction of energy saving, high efficiency and high speed. Z306, Z308, Z312 and other multi station automatic cold heading machines have been successfully developed, and the serialization has been realized. At the same time, the new technology of cutting hexagon head and cold upsetting concave hexagon head has been adopted, and products such as high-strength bolts have been developed. In 1982, Shanghai Institute of Standard Parts Company and Shanghai No. 3 Standard Parts Factory jointly designed and successfully manufactured 5Z41-24 5-station large material small deformation multi station automatic cold heading machine by Shanghai Standard Parts Machinery Factory, which reduced the material cracking rate from more than 15% to less than 5%. In 1988, Shanghai Standard Parts Co., Ltd. successfully organized the design and manufacture of ZM5-500 new type large material small deformation multi station automatic cold heading machine, which expanded the product specifications of high-strength nuts and promoted the development of special-shaped nuts.

Many manufacturers in China are making this equipment, but more than 90% of them are "copied" based on Taiwan Chunri Machinery, without independent intellectual property rights. At present, the leading representative is Qiqihar No. 2 Machine Tool Factory, which is in the leading position in the industry. Especially in 2004, through the cooperation and exchange with Sakura Machinery, Japan, it successively developed BP-440SS and BP-430SS cold heading machines, whose comprehensive performance has reached the international middle level. However, the concept and method of green manufacturing were not integrated into the design and process. In general, although some advanced technologies have been adopted in China in recent years, there is a considerable gap in automation, manufacturing capacity, manufacturing accuracy, productivity and cost control compared with foreign countries