Pascal's Law Applied: Pressure Multiplication

A pressure intensifier (also called a pressure booster or multiplier) uses the principle of Pascal's Law with pistons of different areas to multiply hydraulic pressure. The output pressure is increased in proportion to the ratio of piston areas.

Intensification Ratio Formula

Ratio = (D1 / D2)^2 = A1 / A2

• D1 = Primary (large) piston diameter
• D2 = Secondary (small) piston diameter
• A1 = Primary piston area
• A2 = Secondary piston area

Output Pressure Calculation

P_out = P_in x Ratio x Efficiency

• P_out = Output (high) pressure
• P_in = Input (supply) pressure
• Efficiency = Typically 90-98% (seal friction losses)

Flow Relationship (Conservation of Energy)

As pressure increases, flow decreases proportionally:

Q_out = Q_in / Ratio

This is why intensifiers are used for applications needing high pressure but low flow.

Common Applications

• High-Pressure Clamping: Machine tool workholding, injection molding
• Pressure Testing: Hydrostatic testing of vessels, pipes, valves
• Water Jet Cutting: Ultra-high pressure water jet systems (60,000+ psi)
• Press Operations: Deep drawing, coining, where high force needed for short stroke
• Accumulator Charging: Boosting pressure beyond pump capability

Design Considerations

• Higher ratios (>10:1) may have sealing challenges at the high-pressure end
• Stroke length is typically limited (short-stroke applications)
• Continuous-duty vs intermittent-duty affects cooling requirements
• Cylinder timing and end-of-stroke deceleration important for longevity