Hydraulic Technical Data


 

Resources

Hydraulic Symbols

Hydraulic Force: Formulas & Calculator

Hydraulic Cylinder: Volume Displacement

Hydraulic Oil Pump: HP Required

Hydraulic Pump: Capacity


General Fluid Power Guidelines

Horsepower for driving a pump:

For every 1 hp of drive, the equivalent of 1 gpm @ 1500 psi can be produced.

 

Horsepower for idling a pump:

To idle a pump when it is unloaded will require about 5% of it's full rated power

 

Wattage for heating hydraulic oil:

Each watt will raise the temperature of 1 gallon of oil by 1° F. per hour.

 

Flow velocity in hydraulic lines:

Pump suction lines 2 to 4 feet per second, pressure lines up to 500 psi - 10 to 15 ft./sec., pressure lines 500 to 3000 psi - 15 to 20 ft./sec.; all oil lines in air-over-oil systems; 4 ft./sec.

Basic Fluid Power Formulas

Variable Word Formula w/ Units Simplified Formula
Fluid Pressure - P (PSI) = Force (Pounds) / Area ( Sq. In.) P  =  F / A
Fluid Flow Rate - Q GPM= Flow (Gallons) / Unit Time (Minutes) Q = V / T
Fluid Power in Horsepower - HP Horsepower = Pressure (PSIG) × Flow (GPM)/ 1714 HP = PQ / 1714
 

Actuator Formulas

Variable Word Formula w/ Units Simplified Formula
Cylinder Area - A ( Sq. In.) = π × Radius (inch)2 A  =  π  × R2
(Sq. In.) = π × Diameter (inch)2 / 4 A  = π  × D2 / 4
Cylinder Force - F (Pounds) = Pressure (psi)   × Area (sq. in.) F  =  P × A
Cylinder Speed - v (Feet / sec.) = (231 × Flow Rate (gpm)) / (12 × 60 × Area) v   =  (0.3208 × gpm) / A
Cylinder Volume Capacity - V Volume = π × Radius2 × Stroke (In.) / 231

V = π × R2 × L / 231

(L = length of stroke)

Cylinder Flow Rate - Q Volume = 12 × 60 × Velocity (Ft./Sec.) × Net Area(In.)2 / 231 Q = 3.11688 × v × A
Fluid Motor Torque - T Torque (in. lbs.) = Pressure (psi) × disp. (in.3 / rev.) / 6.2822 T  =  P × d / 6.2822
 
Torque = HP × 63025 / RPM T = HP × 63025 / n
Torque = Flow Rate (GPM) × Pressure × 36.77 / RPM T = 36.77 × Q × P / n
Fluid Motor Speed - n Speed (RPM)  =  (231 × GPM) / Disp. (in.)3 n  =  (231 × GPM) / d
Fluid Motor Horsepower - HP HP = Torque (in. lbs.) × rpm / 63025 HP  =  T × n / 63025
 

Pump Formulas

Variable Word Formula w/ Units Simplified Formula
Pump Output Flow - GPM GPM = (Speed (rpm) × disp. (cu. in.)) / 231 GPM =  (n ×d) / 231
Pump Input Horsepower - HP HP =  GPM × Pressure (psi) / 1714 × Efficiency HP  =  (Q ×P) / 1714 × E
Pump Efficiency - E Overall Efficiency = Output HP / Input HP EOverall = HPOut / HPIn X 100
Overall Efficiency = Volumetric Eff. × Mechanical Eff. EOverall = EffVol. × EffMech.
Pump Volumetric Efficiency - E Volumetric Efficiency = Actual Flow Rate Output (GPM) / Theoretical Flow Rate Output (GPM) × 100 EffVol. = QAct. / QTheo. X 100
Pump Mechanical Efficiency - E Mechanical Efficiency = Theoretical Torque to Drive / Actual Torque to Drive × 100 EffMech = TTheo. / TAct. × 100
Pump Displacement - CIPR Displacement (In.3 / rev.) = Flow Rate (GPM) × 231 / Pump RPM CIPR = GPM × 231 / RPM
Pump Torque - T Torque = Horsepower × 63025 / RPM T = 63025 × HP / RPM
Torque = Pressure (PSIG) × Pump Displacement (CIPR) / 2π T = P × CIPR / 6.28

 Training

Throughout the year, we will hold various training events to inform and educate attendees on Hydrotech products, divisions, and principles of hydraulic technologies.

CLICK HERE to view upcoming training events and register today  

 Whitepapers

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 Hydraulic Technical Data

  • Basic Fluid Power Formulas
  • Actuator Formulas
  • Pump Formulas
  • General Fluid Power Guidelines

 Pneumatic Technical Data

  • Valve Sizing for Cylinder Actuation Direct Formula
  • Calculators
  • Converters

 Electrical Technical Data

  • Electrical Units
  • Electrical Formulas

 Media Downloads

 Events

09-25-2017  |  Level 2 Hydraulic Training - Hydraulic System Maintenance
The goal of this 2nd level industrial hydraulic course is to develop maintenance personnel with advanced hydraulic skills.

01-30-2017  |  Level 1 Hydraulic Training - Principles of Hydraulics
This is a 5 day training program that teaches maintenance personnel the principles of industrial hydraulics.

VIEW ALL UPCOMING EVENTS