Pneumatics — Cheat Sheet
Cylinder force, air consumption, gas laws, Cv/flow and choked flow.
Cylinder force
| Extend | F = p·πD²/4 |
| Retract | F = p·π(D²−d²)/4 |
| Piston speed | v = Q / A |
| Gauge vs absolute | p_abs = p_gauge + p_atm |
Air consumption
| Free air / stroke | V = A·stroke·(p_abs/p_atm) |
| Both strokes | add extend + retract volumes |
| Flow rate | × cycles per minute |
Gas laws
| Ideal gas | pV = mRT |
| Boyle (isothermal) | p₁V₁ = p₂V₂ |
| Combined | p₁V₁/T₁ = p₂V₂/T₂ |
Flow & sizing
| Valve flow | Q ∝ Cv·√Δp (below choke) |
| Choked flow | when p₂/p₁ < 0.528 (air) |
| Rule | size valves & lines for the flow, not just the port |
Formula reference — verify against the governing standard. Not a substitute for engineering judgment.