Efficiencies of hydraulic presses
If the press is optimally adjusted, the efficiencies that can be achieved are comparable to those of mechanical presses. However, it turns out that an optimal setting cannot be achieved during deep drawing due to the long travel distances and the large compression volume of the master cylinder, which drastically reduces the overall efficiency ηtot.63
In addition, it is common practice to push the material to be drawn back onto a transport level, which requires additional long lead paths.
Drawing in the predraw to produce flanges also requires a pressure holding time, which also significantly reduces the efficiency.
The usual overall efficiencies ηtot for deep drawing with flange and transfer can be below 0.2.67
Favorable setting ηtot = 0.4... 0.6