Flow State 1 32 Hydraulic Oil
The antiwear agents contained in the oil protect the hydraulic pump components from premature wear. Figure 1 summarizes ISO 32, 46, and 6 8, the most commonly used viscosity grades because they have the appropriate viscosity at the temperatures usually seen in industrial hydraulic systems. The temperature operating range is based on the lowest. Hydraulic Oil Flow through Orifices It may be used for designing limiting flow orifices in hydraulic systems. Chart values must be considered as approximate because a number of factors such as specific gravity, orifice efficiency, plumbing ahead of and behind the orifice may cause variations from the values shown.
ISO 32 Hydraulic Oil – ISO VG 32 Hydraulic Fluid is ideal for use in high-powered machine tools. ISO 46 Hydraulic Oil – ISO VG 46 Hydraulic Fluid is normally required for industrial plant working under high-pressure etc. ISO 68 Hydraulic Oil – ISO VG 68 Hydraulic Fluid is designed for use in systems which require a large load-carrying.
Formula
Pressure, Force and Horsepower Relationships:
Pressure (psi) = force (lbs) / area (in²)
Force (lbs) = area (in²) x pressure (psi)
Area (in²) = force (lbs) / pressure (psi)
Fluid Power Horsepower:
Fluid Power Horsepower (hp) = pressure (psi) x pump flow (gpm) / 1,714
Torque and Horsepower Relationships:
Torque (ft lbs) = horsepower (hp) x 5,252 / speed (rpm)
Horsepower (hp) = torque (ft lbs) x speed (rpm) / 5,252
Speed (rpm) = horsepower (hp) x 5,252 / torque (ft lbs)
Basic Cylinder Calculations:
Piston Cylinder Area (in²) = diameter squared x .7854
(Can also use 3.1416 x radius squared (ins) )
Piston Rod End (annulus end) Area (in²) = piston cylinder area (in²) - rod area (in²)
Cylinder Force (lbs) = pressure (psi) x area (in²)
Cylinder Speed (ft/min) = 19.25 x flow rate (gpm) / area (in²)
(Divide by 60 to convert speed to ft/sec)
Cylinder Speed (in/min) = flow rate (cu ins/min) / area (in²)
(Note that 1 US gallon = 231 cu ins)
Cylinder Time (secs) = area (in²) x cylinder stroke (ins) x .26 / flow rate (gpm)
Cylinder Flow Rate (gpm) = 12 x 60 x cylinder speed (ft/sec) x area (in²) / 231
Cylinder Volume Capacity (gals) = cylinder area (in²) x cylinder stroke (ins) / 231
Basic Hydraulic Motor Calculations:
Motor Torque (in lbs) = pressure (psi) x motor displacement (cu ins/rev) / 6.28
(Can also use horsepower (hp) x 63,025 / speed (rpm)
Motor Speed (rpm) = 231 x flow rate (gpm) / motor displacement (cu ins/rev)
Motor Horsepower (hp) = torque (in lbs) x motor speed (rpm) / 63,025
Motor Flow Rate (gpm) = motor speed (rpm) x motor displacement (cu ins/rev) / 231
Motor Displacement (cu ins/rev) = torque (in lbs) x 6.28 / pressure (psi)
Basic Pump Calculations:
Pump Outlet Flow (gpm) = pump speed (rpm) x pump displacement (cu ins/rev) / 231
Pump Speed (rpm) = 231 x pump flow rate (gpm) / pump displacement (cu ins/rev)
Pump Horsepower (hp) = flow rate (gpm) x pressure (psi) / 1,714 x pump efficiency factor
(Can also use horsepower (hp) = torque (in lbs) x pump speed (rpm) / 63,025)
Pump Torque (in lbs) = pressure (psi) x pump displacement (cu ins/rev) / 6.28
(Can also use horsepower (hp) x 63,025 / pump displacement (cu ins/rev)
Heat Generation Formulas: Converting heat into other units
1 hp = 2,545 BTU/hr = 42.4 BTU/min = 33,000 ft. lbs./min = 746 watts
Horsepower (hp) = pressure (psi) x flow (gpm) / 1714 -or- BTU/hr = 1½ x psi x gpm
1 BTU/hr = .0167 BTU/min = .00039 hp
Example: 10 gpm flow across a pressure reducing valve with a 300 psi drop = 1.75 hp of heat generated
1.75 hp of heat = 4,453 BTU/hr = 105 BTU/min = 57,750 ft. lbs./min = 1,305 watts
- Most of this heat will be carried back to the reservoir.
- Note that heat is generated anytime no mechanical output work is produced
General cooling capacity of a steel reservoir: HP (heat) = .001 x TD x A
TD = temperature difference of the oil in the reservoir and the surrounding ambient air
A = entire surface area of the reservoir in square feet (including the bottom if elevated)
General Information and “Rules of Thumb”:
Estimating pump drive horsepower: 1 hp of input drive for each 1 gpm at 1,500 psi pump output
Horsepower when idling a pump: an idle and unloaded pump will require about 5% of its full rate hp
Reservoir capacity (GALS) = length (INS) x width (INS) x height (INS) / 231
Oil compressibility: 1/2 % approximate volume reduction for every 1,000 psi of pressure
Water compressibility: 1/3 % approximate volume reduction for every 1,000 psi of pressure
Wattage to heat hydraulic oil: each 1 watt will raise the temperature of 1 gallon of oil by 1°F per hour
Guidelines for flow velocity in hydraulic lines:
- 2 to 4 ft/sec = suction lines
- 10 to 15 ft/sec = pressure lines up to 500 psi
- 15 to 20 ft/sec = pressure lines 500 – 3,000 psi
- 25 ft/sec = pressure lines over 3,000 psi
- 4 ft/sec = any oil lines in air-over-oil systems
Velocity of oil flow in a pipe: velocity (ft/sec) = flow (gpm) x .3208 / inside area of the pipe (sq ins)
Circle area formulas:
- Area (sq ins) = π x r² where π (pi) = 3.1416 and r = radius in inches squared
- Area (sq ins) = π x d² / 4 where π (pi) = 3.1416 and d = diameter in inches
- Circumference (ins) = 2 x π x r where π (pi) = 3.1416 and r is radius in inches
- Circumference (ins) = π x d where π (pi) = 3.1416 and d = diameter in inches
Commonly Used Fluid Power Equivalents:
One US gallon equals:
- 231 cubic inches
- 3.785 liters (1 liter = .2642 US gals)
- 4 quarts or 8 pints
- 128 ounces liquid / 133.37 ounces weight
- 8.3356 pounds weight
Hydraulic Oil Iso 32
One horsepower equals:
- 33,000 ft lbs per minute
- 550 ft lbs per sec
- 42.4 BTU per min
- 2,545 BTU per hour
- 746 watts
- 0.746 kw
On psi equals:
- .0689 bar (1 bar = 14.504 psi)
- 6.895 kilopascal
- 2.0416 hg (inches of mercury)
- 27.71” water
One atmosphere equals:
- 14.696 psi
- 1.013 bar
- 29.921 hg (inches of mercury)
Note: This information is provided as a quick reference resource and is not intended to serve as a substitute for qualified engineering assistance. While every effort has been made to ensure the accuracy of this information, errors can occur. As such, neither Flodraulic, any of its affiliated companies nor its employees will assume any liability for damage, injury or misapplication as result of using this reference guide.
Flow State 1 32 Hydraulic Oil Pump
Pipeline Hydraulic Analysis - Static State
This tool was designed to perform static state hydraulic analysis for pipelines. A web-based hydraulic model can be developed per your design to size equipment, verify existing pump performance, or plan for future upgrade. Either Darcy-Weisbach method or Hazen-Williams method can be used for pipe friction loss calculations. If Darcy-Weisbach method is selected, Colebrook equation will be used to determine the friction factor.
Hydraulic Summary - Pump Discharge System
Tabular Result
Pump Summary