Servo vs. Mechanical: Understanding Tonnage and Energy
"Since the motion of a servo press is programmable, some users wrongly believe that the tonnage available through the full stroke of the press is like that of a hydraulic press. However, servo presses have a mechanical drivetrain (eccentric gear or shaft); therefore, the tonnage curve basically will be the same as with a mechanical press. Stampers must review the press' tonnage curve vs. the specific applications in regard to loads higher in the stroke."