Introduction to spinning process

What is spinning technology? It is also called metal spinning forming technology. It is a technology that makes the stress point go from point to line, from line to surface through rotation, and at the same time, gives a certain pressure in a certain direction to make the metal material deform and flow along this direction to form a certain shape. Here, metal materials must have plastic deformation or flow performance. Spinning is not equivalent to plastic deformation. It is a complex process integrating plastic deformation and flow deformation. It should be pointed out that the spinning technology is not a single powerful spinning and ordinary spinning, but a combination of the two; Powerful spinning is used for the processing technology of spinning forming shells of various cylinders and cones. It is an old and mature method and process, also called rolling method.

In mechanical products, how to save raw materials can improve product quality, reduce product weight can prolong service life, reduce product manufacturing cost and energy consumption can reduce processing hours has always been a concern. For example, “V” pulley (commonly known as “V” pulley) is one of the mechanical transmission parts with a wide range of applications. It is of great significance if it can be formed from steel plates. Compared with the traditional cast iron pulley, the sheet metal pulley can save more than 70% of raw materials. The spinning belt pulley formed by stretching and spinning of metal sheet metal is the latest and best belt pulley structure. This kind of pulley not only has the advantages described above, but also has no environmental pollution. It is especially widely used in automobiles, tractors, harvesters, air compressors and other mechanical products. The steel sheet blank is made of plastic deformation from point to line and from line to surface on the special belt pulley spinning machine tool. Spinning pulley generally has three basic forms: folding pulley, split pulley and rolling multi V pulley (also called multi wedge pulley).

Compared with cast iron belt pulley, spinning belt pulley has the advantages of adopting spinning process (no chip processing), light structure, material saving, and small moment of inertia. It is a new product with material saving and energy saving. High production efficiency (processing 2~4 pieces per minute), good balance performance, generally without balance treatment. As the material streamline is not cut off, the surface is cold worked and hardened, and the organization density is increased, the strength and hardness of the wheel groove surface are improved, and the size accuracy is high, the slip between the V-belt and the wheel groove is small, and the belt life is long.

CDC-S60 vertical CNC spinning machine

The belt pulley spinning forming process and equipment is an advanced technology. A series of scientific research achievements have been made in the belt pulley spinning process, including folding belt pulley, split belt pulley, rolling multi V belt pulley and combined belt pulley. Various technical problems in spinning forming have been solved in theory and practice, and have been successfully used in production. However, compared with the spinning technology in Germany, China still needs to make efforts to catch up, because many products in China still need to be imported, especially some parts in automobiles.

Introduction to spinning products

CDC-S series CNC spinning machine is a special equipment for spinning pulley. As a new process product, spinning pulley has been widely used in automobile engines, such as motor wheel, water pump wheel, air conditioner wheel and fan wheel. According to the groove type and processing technology of belt pulley, it can be divided into three categories: split pulley, folding pulley and multi wedge pulley. Due to the different structural characteristics of the three types of spinning pulleys, their processing technologies are also different.

The thickness of materials selected for the multi wedge wheel is 2~6mm, generally 3mm. The blank is made by drawing and stamping, and is processed on a spinning machine. As the tooth shape is formed by metal flow and plastic deformation on the material wall thickness by extrusion, there are many factors affecting the final quality of the product, including upper and lower dies, spinning wheels, process parameters, material materials, etc. It will be introduced in detail in the future process analysis and mold design.

The thickness of the material selected for the folding wheel is 1.5~2.5mm, which is also made by drawing and stamping, and processed on the spinning machine. Since no metal flow occurs during the forming process of the folding wheel, the process is relatively simple and there are few factors affecting the quality.

The material thickness of the splitting wheel is 2~4mm. Generally, one time blanking is used to make the blank, and the spinning wheel is used to split from half of the material thickness on the spinning machine and then reshape to form. Because of its simple processing technology and few factors affecting the quality, the most important is the flatness of the blank itself. Therefore, the punching die for offset cutting has higher requirements.