How to Size a Shock Absorber for Rotary Motion
Convert rotary motion into rotational energy and absorber stroke at the contact radius.
Direct answer
For rotary motion, calculate rotational kinetic energy from inertia and angular speed, then translate the absorber contact radius and stop angle into effective stopping stroke. Beam, gate and rotary-table cases need different inertia assumptions.
Questions this page answers
- How do I size a shock absorber for rotary motion?
- How do I calculate a shock absorber for a rotary table?
- How do I select a shock absorber for a swinging arm or gate?
Required inputs
Formula logic
Angular speed
Converts rotational speed into angular velocity.
omega = rpm x 2 x pi / 60Unit: rad/s
Rotational kinetic energy
I is the moment of inertia for the rotating body.
E = 1/2 x I x omega^2Unit: N m
Arc stroke
r is absorber contact radius and theta is stop angle in radians.
s = r x thetaUnit: mm
Calculation steps
- 1
Choose the rotary body model
Identify whether the case is a rotary load, beam/gate or rotary table.
- 2
Calculate rotational energy
Use inertia and angular speed, then add gravity torque work for vertical rotation if needed.
- 3
Check effective absorber stroke
Use the contact radius and stop angle to confirm that the absorber stroke is sufficient.
Common mistakes
- Using linear velocity without converting the rotary geometry.
- Using the wrong inertia model for a beam or gate.
- Ignoring gravity torque in vertical rotary motion.
Catalog source notes
- The product catalog describes shock absorber use across linear and rotary/drive-related applications; the current site calculator registry already implements rotary load, beam/gate and table variants.
Move from answer to model shortlist.
Use the sizing tool when you have the inputs, or send the application data for engineering review.