Hydraulic Pumps - Capacity Required

Calculate required hydraulic pump output

Required hydraulic pump capacity can be calculated as

q = 0.26 A s / t         (1)

where

q = pump output capacity (gpm)

A = area of cylinder (square inches)

s = piston stroke (inches)

t = required time for full stroke (s)

• 1 gpm (US) =6.30888x10^-5 m³/s = 0.227 m³/h = 0.06309 dm³(litre)/s = 2.228x10^-3 ft³/s = 0.1337 ft³/min = 0.8327 gpm (UK)
• 1 in (inch) = 25.4 mm = 2.54 cm = 0.0254 m = 0.08333 ft
• 1 in² = 6.452 cm² = 6.452x10^-4 m² = 6.944x10^-3 ft²

Required pump output for hydraulic cylinders ranging 1 - 6 1/2 inches are indicated below. Multiply pump capacity with stroke length (in).

Example - Required Pump Capacity

A 3" hydraulic cylinder with cylinder area 7.065 in² moves a 30 inches stroke in 3 seconds. Required pump capacity can be calculated as

 q = 0.26 7.065 (in²) 30 (in) / 3 (s)

    = 18.4 gpm        

Engineering News

Resources, Tools and Basic Information for Engineering and Design of Technical Applications!