Critical speed for a leadscrew
Description
The critical speed is the speed that excites the natural frequency of the screw. For a steel leadscrew or steel ballscrew, the critical speed is approximately
Furthermore the running speed for a leadscrew (or ball screw) is typically limited to, at most, 80% of the calculated critical speed.
Constant C values for steel leadscrew or steel ballscrew, depending on the ends:
C = 0.36 for one end fixed, one end free
C = 1.00 for both ends simple
C = 1.47 for one end fixed, one end simple
C = 2.23 for both ends fixed
Variables
N | Critical speed (rpm) |
dr | Smallest (root) diameter of the leadscrew (in) |
C | Constant for steel leadscrew or steel ballscrew depending on the end of the leadscrew (rpm*in) |
L | Length between bearing supports (in) |