TABLE OF CONTENTS According to their characteristics, presses can be classified into those controlled mainly by work (energy), the ram path or force.
Hammers and screw presses are machines whose main characteristic is their work capacity (energy). A hammer s work capacity is determined from the ram mass and drop height. With screw presses, the work capacity is stored in the rotating masses (mainly in the flywheel), therefore it depends upon the angular velocity and the mass moment of inertia. The two kinds of machine are similar in that the work capacity can be influenced or adjusted.
The force, on the other hand, can not be directly adjusted, but depends upon the kind of work-piece and the deformation distance.
These include crank presses and knuckle-joint presses. With these presses, the deformation is complete when the ram has reached its lowest position (bottom dead centre BDC). This means their characteristic value is the ram path limit, which comes from the crank radius r in crank presses and from the leverage with knuckle-joint presses...
