Spinning thin-walled parts are widely used in various industries, such as automobile shock absorbers, military accessories, lighting lampshades, hardware tableware, etc. Many designers need to consider the forming ability of the spinning process when designing spinning thin-walled parts. The following will introduce in detail.
1. About the thinning rate of CNC Metal Spinning
Many designers have a biased understanding of the thinning rate of spinning. The common thinning rate of stamping and stretching is generally about 10%, and the thinning rate of manual spinning is about 10%. , The maximum thinning rate of the material is about 40%. But the strength of CNC spinning parts with the same wall thickness is better than that of stamping and stretching. For thin-walled parts under internal pressure, the strength of stamping and drawing parts is very poor, and they are easy to crack, and welded round parts are also easy to crack. The best way is to use spinning as a whole to improve the strength of the product.
2. About the processing limit of CNC spinning
At present, the general thickness of CNC spinning machines in the market is 3mm for stainless steel plate, 4mm for strong spinning, 6mm for aluminum plate, 8mm for strong spinning, 4mm for iron plate, and 5mm for strong spinning. If the height of the stainless steel straight barrel exceeds 200mm, it is generally easy to crack. When the height of the straight barrel exceeds 200mm, you can consider making a head at the bottom, and then roll welding a round pipe. The head and the round pipe are welded. The maximum height of the straight iron barrel can be 400mm for spinning, and the height of aluminum can exceed 700mm due to the good ductility of the material itself. However, considering that the demoulding length of the general spinning machine on the market is generally 500mm, the maximum height of the aluminum barrel is best designed to be 500mm .
3. About the stability of CNC spinning products
Generally, the accuracy of stamping and stretching thin-walled parts is better than that of spinning, but when working for a long time, or when the part itself heats up, the stability of precision and strength of CNC spinning products at different temperatures is better than others. The craftsmanship is better, this is the advantage of spinning products, and it is also the biggest reason why most military accessories are made of spinning technology.
4. About the thickness distribution of spinning products
The thickness of CNC spinning products is unevenly distributed, because the thinning rate of shear spinning and floating knife general election is different. However, when the tapered product is forced to spin, the tapered wall thickness of the spinning product can reach a uniform thickness, such as the strong spinning process of the drug-shaped cover of the military accessory product. The thickness of the bottom of the plate spinning product is generally not much different from the thickness of the blank, because it has not been thinned here. However, the diameter of the bottom and the maximum diameter of the product are very different, and the wall thickness of the bottom will still change slightly.
5. How to improve the local strength of thin-walled spinning products
For example, for a spinning product with a diameter of 200mm, when the metal wall thickness is less than 1.0mm, the local strength of the product is not very good, and the strength of the product needs to be considered. The following diagrams illustrate different ways to enhance the local strength.
6. About the surface texture effect of spinning products
The general surface treatment of spinning products is polishing or stretching, oxidation, and painting. The calendered surface of the aluminum part can cover the spinning pattern without polishing the diameter by powder spraying or sandblasting, but the oil spraying, electroplating, and oxidation require the surface to be stretched.
