SPINNING is a method of forming sheet metal into seamless, axisymmetric shapes by a combination of rotation and force. On the basis of techniques used, applications, and results obtainable, the method can be divided into three categories: Manual spinning , Power spinning, Tube Spinning.
Manual spinning is used to form flanges, rolled rims, cups, cones, and double-curved surfaces of revolution (such as bells). Several typical shapes formed by manual spinning are shown in Fig. 1. Products include light reflectors, tank ends, covers, housings, shields, and components for musical instruments. Manual spinning is also extensively used for the production of aircraft and aerospace components, often with mechanical assistance for increased force.
Classification Of Metal Spinning Processes:
Manual (Conventional) Spinning
- Practiced by pressing a tool against a circular metal preform.
- Involves no significant thinning of work metal; essentially a shaping process.
- Used for prototype manufacture or in production runs less than 1000 pieces.
- Metal is deformed using high shear forces.
- Use of automated CNC machines.
- Significant thinning of metal preforms.
- Suitable for high production runs.
Thickness of cylindrical parts reduced by spinning them on cylindrical mandrel rollers.
This step involves the laying down of the material onto the mandrel.
It is accomplished with short inside to outside moves.Material gets easier to form as the part is closer to completion