Servo Applications: Prolonged Die Life; Increased Tolerances, Faster Forming Speeds

This is another comparison between the typical press and servo press.  To the left side; the parts are rails of stainless steel with a production run of 100,000 pieces.  With the typical press the speed is only 20 spm but in the servo the average is 50 SPM with 40 times the die life and better tolerance because for pendulum motion profiles and ability to slow the stroke speed at BDC. That's money saved! The right side are handles made of hi-tensile steel.  This is just blanking so the speed is just about the same.  You do not have to worry about the die speed angle.  But there is a difference in die life and tolerances, again because you can slow down the stroke speed at bottom dead center.  And, of course, the tolerances are getting better because when you’re at bottom dead center of the working area you can slow down the speed and that will increase the die life.  Lesson learned; you can run tighter tolerances on the servo because you can run with slower speeds at BDC, whereas with a conventional press you have to open the tolerances because there is more friction, more heat.  You’ll end up breaking punches.