First, the characteristics of CNC spinning processing

The characteristics of CNC spinning are suitable for small and medium-sized batch production, processing materials with large wall thickness, large forming stretch length, medium processing precision and complex shape.

Compared with CNC spinning, the manual spinning technology is limited by manpower, and it is impossible to process the spinning products with large thickness. However, when the stamping and drawing process processes the metal molding products of the same thickness, the processing force required is the spinning 3 -5 times, so punching and drawing aluminum, 2mm stainless steel, and 3mm iron with a thickness of more than 4mm requires a large tonnage punch or hydraulic press. When the product is mass-produced, the speed of stamping and drawing forming will be faster than that of CNC spinning, and the unit cost is lower. For products with a large tensile length, the stretch stamping is easy to crack, and the single-piece product is spin-formed for a long time. Usually, the semi-finished blank is firstly formed by hydraulic drawing, and then the final forming process is performed by spinning. The combination of processes can greatly improve the production efficiency of products, and can reduce the scrap rate of products. Aluminum and iron products are easy to combine with spinning and stretching. Due to the high hardness of the stainless steel, the stretched blank is easily cracked through the position of the spinning joint.

The numerical precision of CNC spinning machine is 0.04mm. Due to the influence of material flow and stress rebound during spinning process, the precision of processed products cannot reach 0.04mm. Among the three materials of aluminum, iron and stainless steel, the precision of stainless steel spinning products The most difficult to control, based on the diameter of 100mm, the diameter accuracy of general aluminum spinning parts can reach 0.1mm, the diameter accuracy of iron is about 0.2mm, the diameter accuracy of stainless steel is about 0.4mm, the larger the diameter of the product, the worse the precision, the strong rotation The accuracy is higher than that of the general rotation. When the spinning parts have assembly accuracy requirements, they can be finished by precision machining. At present, the products widely used in CNC spinning include lampshades, stainless steel bowls, stainless steel pots, shields, signal reflectors, signal receiver covers, chemical containers, electric containers, aluminum barrels, stainless steel barrels, venturi tubes, fan outlets, Ventilation ducts, funnels, electrical appliances, motor guards, etc. The CNC spinning process is more suitable for such special customized, medium and small batch processing products.

Second, the difference and advantage of CNC spinning and manual spinning

The numerical control spinning and manual spinning are the same in the forming process of the product. The clamping force is provided through the tail top, and the moving piece can be rotated together with the main shaft. The cutting wheel makes the material from point to line according to the predetermined cutting path. The line-to-face extension is finally formed. The difference is that the numerical control spinning is controlled by the numerical control machine tool to control the path of the cutter wheel in the spinning forming process, and the gap between the cutter wheel and the mold. Due to the high running precision of the CNC machine tool, the rigidity of the equipment and the large processing force, the manufactured product has good consistency, stable production and good control of the precision of the product. Manually controlled by the manual in the spinning forming process The rod determines the path of the cutter wheel, and the tool path and the gap between each product are different, resulting in unstable batch product quality.

When the thickness of the spinning material exceeds a certain range (iron exceeds 1.2 mm, aluminum exceeds 1.5 mm, and stainless steel exceeds 1 mm), the artificial force cannot support the processing force required for spinning, and it is easy to cause the product to be scrapped. When hand-spinning aluminum and iron products made of thin parts, the surface of the processed product will be better than the surface of the CNC spinning. However, in recent years, after the numerical control spinning has been continuously improved by the process technology, the outer wall surface of the spinning product has been very similar to the manual spinning.

Third, the difference and advantages of spinning and stamping and drawing processing

Both spin forming and stamping and drawing can form the web. The specific differences and advantages are as follows:

The difference between the principles: Spinning is to control the flow and deformation of the web by the path of the cutter wheel, and the stretch stamping process is to control the flow of the web by the cooperation of the upper and lower convex and concave molds.

Mold difference: to do the same hardware molding product, spin forming only needs to make one core mold, and stretch stamping needs to make two concave and convex molds, the manufacturing cost of the mold is usually 3-6 times of spinning, while spinning The manufacturing cycle of the mold is shorter than that of the stretch stamping die, and the size is easier to modify.

Material difference: Spinning processing thinning rate is usually about 30%, stretch stamping processing is about 10% thinner, and the thinning rate is relatively larger, while stretch stamping requires about 5-10mm of crimping material, the required material The cost is big.

Processing difference: For some simple metal forming products, there are many stretching and stamping forming processes, including basic processes such as cutting, forming and trimming. Some products have to be stretched many times during the molding process, and the process is complicated but the processing speed is relatively faster. Spin forming and cutting can be done on one CNC spinning machine at the same time, but the processing speed of one piece will be slow; for some products with long or irregular stretching height, stretch stamping will cause cracking of the product, but spinning It is easier to complete the molding of the product.

Product difference: On the surface of the product, the spinning embossing is distributed in a circle, and the stretching is distributed in a vertical line; in terms of strength after molding, the strength of the spinning product will be much better than that of the stretching.