MPP Formulas for PTOs and Hydraulics
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|
TO SOLVE FOR |
CALCULATOR ENTRY* |
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PTO Output Speed |
PTO RPM = ENGINE RPM x PTO% |
|
Required Engine Speed |
ENGINE RPM = DESIRED PTO RPM ÷ PTO% |
|
Horsepower |
HP
= T X RPM ÷ 5252 |
|
Torque |
T = HP X 5252 ÷ RPM |
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|
Area of a Circle |
A
= πr2 or A = d2 X
.7854 |
|
Volume of a Cylinder |
V = πr2
X Li ÷ 231 or d2 X .7854 X Li ÷ 231 |
|
Force of a Cylinder |
F = A X PSI |
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Cylinder Extension (inches/second) |
EXT. RATE = GPM X 4.9 ÷ d2 |
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Cylinder Extension (time to extend) |
EXT. TIME = CYL. VOLUME X .26 ÷ GPM |
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Volume of a Reservoir (rectangular) |
VOL = Li X Wi X Di ÷ 231 |
|
Volume of a Reservoir (round) |
VOL
= πr2 X Li ÷ 231 or d2
X .7854 X Li ÷ 231 |
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|
Pump Output Horsepower |
HP = GPM X PSI ÷ 1714 |
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Pump Input Horsepower |
HP = GPM X PSI ÷ 1714 ÷ E |
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Pump Input Torque (ft.lb.) |
T = CID X PSI ÷ 2π |
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Pump Output Flow |
GPM = CIR X RPM ÷ 231 X E |
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Pump Input Speed |
RPM = GPM X 231 ÷ CIR ÷ E |
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Displacement of Pump |
CIR = GPM X 231 ÷ RPM ÷ E |
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|
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Flow in GPM using PTO |
GPM = ENGINE RPM x PTO% X CIR ÷ 231
X E |
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Velocity of Oil |
V = GPM X .3208 ÷ A |
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Heat Rise in Degrees F |
ΔF° = HP X 746 X Inefficiency X
Minutes ÷ Gallons in system ÷ 60 |
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The following
hydraulic motor formulas are calculated in inch
pounds (in.lb) rather than foot pounds. To
convert to ft.lb divide by 12. |
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Motor Output Torque |
|
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Continuous |
Tc =
GPM X PSI X 36.77 ÷
RPM or
Tc
= CID X PSI
÷ 2 π or
Tc
= HP X
63025 ÷ RPM
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|
Starting |
Ts =
Tc X 1.3
|
|
Accelerating |
Ta =
Tc X 1.1
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|
Motor Working Pressure |
T X 2 π ÷ CIR
÷ E
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Motor RPM |
RPM =
GPM X 231 ÷
CIR
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