Just like a clockwork

The basic principle of rotary swaging can be easily explained: Several die segments impact on the workpiece again and again in quick succession. The material starts to flow and is formed in quick succession with high precision.


Precision

Felss Central shaft
Felss Central shaft

This is why the swaging mechanism achieves the accuracy of a clock mechanism. The die segments hit the component at a rate of more than 1000 strokes per minute. The designed forming takes place through an incremental, step by step process. The actual stroke is only 0.25 to 1.5 millimeters per base jaw. A critical mechanism that is determined by the swagging mechanism of the system. In the swagging mechanism, a shaft drives several base jaws with dies. If the base jaws are positioned between two pressure rollers, the dies are in an open position; if the pressure base jaws are under a roller, the dies are closed – and impact on the component. The outer roller cage has a continuous movement resulting from the rotation of the swaging shaft and the specific curve shape of the base jaws. Compensating spacing plates or shims are fitted between the die segments and the base jaws. The outer ring, which is made up of a holding ring and a shrunk-in wear ring, is designed to take the radial forces and is responsible for the rigidity of the machine system. There are two types of rotary swaging machines: Machines with inner rotor and machines with outer rotor. The outer ring is either stationary or, in order to increase the swaging frequency, it is rotated in the opposite direction to that of the swaging shaft.


Optimized pressure base jaws

Structure of a Felss rotary swaging machine
Structure of a Felss rotary swaging machine

Key to having perfect sequences within the rotary swaging system is also the curve profile of the base jaws. The optimized design ensures that the base jaws remain in permanent contact with the rollers. The deceleration and acceleration curve in a radial direction is therefore extremely stable – bringing with it wide-ranging advantages: Even, steady movement: There are no acceleration peaks, the blow frequency is absolutely constant and the wear on the dies is low. Long opening and short closing periods: The machine is optimally aligned. Kinematic and machine dynamics benefit from this. Continuously active drive: Roller and roller cage are driven without the need for additional machine components. Regardless of the desired form of the workpiece, various forming procedures are used for rotary swaging: Infeed swaging, recess swaging or combined processes with or without an internal mandrel.