Talk about the stretching spinning, necking-in spinning, and necking-out spinning of Metal Spinning Machine

24/11/2022
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When CNC Metal Spinning products with various thin-walled cross-section shapes, it is mainly to change the shape of the slab, while the thickness of the slab changes less, and this type of spinning is called ordinary spinning. The basic methods of ordinary spinning mainly include: stretching spinning, necking-in spinning, and necking-out spinning
1. Stretching spinning
Stretch spinning is a forming process that reduces the diameter of the blank (sheet or preform) by radial drawing as the main body. It can also be said that it is similar to stretch forming, but instead of a punch, a mandrel is used, and a rotary wheel is used instead of a punch. It is the main and widely used forming method in ordinary spinning. Bending plastic deformation of the blank is its main deformation mode.
2. Necking-in spinning
Necking-in spinning is the use of spinning tools to perform radial partial rotary compression on a hollow part of a rotary body or a tubular blank to reduce its diameter. The process of shrinking spinning is to clamp the blank concentrically in a suitable core mold (such as solid core, combined or coreless mold), and expose the part that needs to be formed to the outside of the fixture. When the spindle drives the blank to rotate, According to the control method adopted, the rotary wheel reciprocates according to the specified shape and trajectory, and gradually reduces the diameter of the blank, thereby obtaining a part with a waist drum shape or a closed spherical shape.
3. Necking-out spinning
The spinning forming method in which the diameter of the hollow revolving body container or tubular blank is partially increased (in the middle or at the end) by using a spinning tool is called necking-out spinning.