Theoretical extend & retract
Pneumatic cylinder force
Inputs
Nominal internal bore diameter.
Rod diameter used to reduce retract-side area.
Pressure at the actuator, not nominal compressor rating.
User-entered multiplier after friction and practical derating, from 0 to 100.
Results
Applied extend force
1.0014
Applied retract force
0.84116
Bore area
1,963.5
Retract-side area
1,649.3
Fextend = P·Abore·η; Fretract = P(Abore − Arod)·η
A first-pass number, not a code check, certification, or approval. Read the method and its limits below. What this is and is not.
Nearby: Trapezoidal motion · Reflected inertia · Clamp-force transfer · Lead-screw force & travel
Method
Formula, when it applies, and when it does not
Calculate the theoretical extend and retract force from bore, rod, supply pressure, and efficiency factor.
Fextend = P·Abore·η; Fretract = P(Abore − Arod)·η
When
- Uniform pressure
- Circular bore and rod
- User-entered derating factor
Don’t
- Pressure times area is theoretical. The applied force factor is user-entered; supply pressure drop, speed, cushioning, side load, seal friction, air flow, impact energy, and safety functions remain outside this screen.