Goodmorning, I know that the mechanical power press constructors give: 1) the diagram of permitted work depending on used number of slide single stroke per minute; 2) the diagram of eccentric loads on the slide (ellipsis graph). But I don't know how they can do these ones. For question 1. I presume that the iter calculation is: - energy for forming: E0=rated Force x rated distance to BDC - energy for deformation press: E1=F^2/2xRigidity press - energy losses: E2= ...? (x% of E0 ?) Total energy: Et=E0+E1+E2 this is the energy in continous operation (permitted work on automatic strokes). Now, for the press flywheel, assuming a slowdown of 20% during continous stroking, the energy stored in the flywheel is: Ev=Et/(1-0.8^2) So the inertial moment of flywheel is: J=Ev/iω^2 where i: grade of non-uniformity, ω: average speed flywheel in rad/s Now the questions are: a) first of all: how can I calculate the drive motor power (kW) ? b) above all: how can I calculate permitted work on single strokes ?? (I've read somewhere the energy in single strokes is about twice-2- of continous operation: why? I don't think 2 is a magic number...) 2) In the end how can I drawing diagram of eccentric loads ? I really thank everyone help me.