Hydraulics & Pneumatics — Cheat Sheet
Cylinder force, flow-to-speed, pump power, Pascal's law.
Cylinder force = pressure × area; the rod steals area on the retract stroke.
Pascal & force
| Pressure | p = F / A |
| Pascal's law | p transmitted equally |
| Cylinder extend | F = p·(πD²/4) |
| Cylinder retract | F = p·π(D²−d²)/4 |
Flow & speed
| Piston speed | v = Q / A |
| Continuity | A₁v₁ = A₂v₂ |
| Flow (L/min→m³/s) | ÷ 60000 |
Power
| Hydraulic power | P = p·Q |
| P (kW) | = p[bar]·Q[L/min] / 600 |
| Pump input | P_in = P_hyd / η |
Rules of thumb
| Rod side is weaker | retract force < extend |
| Pressure ↔ intensifier | p₂ = p₁·A₁/A₂ |
| Reference | see the Hydraulic Cylinder tool |
Formula reference — verify against the governing standard. Not a substitute for engineering judgment.