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Required Horsepower, Tables and Formulas

General Rule of Thumb for Motor Applications

1 HP Electric Motor equals 1 HP Hydraulic Motor1 HP Gasoline Engine equals 2/3 HP Hydraulic Motor1 HP Hydraulic Motor equals 1 2/3 HP Gasoline Engine

1 HP Hydraulic Motor equals 2/3 HP Electric Motor1 HP Electric Motor equals 2 HP Gasoline Engine

Basic Dimensions for SAE Housings and Flywheels

Basic Dimensions for SAE Housings

SAEHsgNo

Pilot Diameter O.D.Bolt

Circle(See Note

Below)

Flywheel HousingBolts & Bolt Holes

"E"

"A" "B" "C" "D" QtyHole

DiameterBoltSize

"00" 31.000 * 33.50 * 16 * 1/2

"0" 25.500 * 26.75 * 16 * 1/2

"1/2" 23.000 * 24.38 * 12 * 1/2

"1" 20.125 21.75 20.875 3.49 12 .484 7/16

"2" 17.625 19.25 18.375 3.94 12 .433 3/8

"3" 16.125 17.75 16.875 3.94 12 .433 3/8

"4" 14.250 15.88 15.000 * 12 .433 3/8

"5" 12.375 14.00 13.125 * 8 .433 3/8

"6" 10.500 12.12 11.250 2.81 8 .433 3/8

All dimensions are in inches unless otherwise specified.

* 3.94 for 8" clutch; 2.81 for 6" and 7" clutch.

"D" = Depth of pilot bore from housing face to shoulder on flywheel or to chrankshaft flange face.

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Basic Dimensions for SAE Flywheels

ClutchSize

DriveRing Pilot

BoltCircle

HousingFace to

FlywheelPilot Bearing Bore Bolt Hole "K"

"F" "G" "H" "J" Qty Size

6.5" 8.500 7.875 1.19 2.0472 (52mm) 6 5/167.5" 9.500 8.750 1.19 2.0472 (52mm) 6 5/16

8" 10.375 9.625 2.44 2.4409 (62mm) 6 3/8

10" 12.375 11.625 2.12 2.8346 (72mm) 8 3/8

11.5" 13.875 13.125 1.56 2.8346 72(mm) 8 3/8

14" 18.375 17.25 1.00 * 8 1/2

18" 22.500 21.38 .62 * 6 5/8

21" 26.500 25.25 0 * 12 5/8

Winch Calculations

Winch horsepower can be approximated by the following formula:

HP = (L) (S)

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(E) (33,000)

Where:HP is the horsepowerL is the load (pounds)S is the cable speed (feet/minute)E is the overall drive efficiency

As cable builds up on a drum the radius changes thereby altering the speed and horse power for aconstant load and RPM drive system. Therefore, the conditions of which load and speed are specifiedmust be defined. It is common practice to specify conditions at mid drum unless other consideratonsdominate in which case they should be used as design criteria.

Drive efficiencies vary greatly on the type of drive, as a guide:

Electric Drive worm gears TYP 60 - 75%Electric Drive Bevel Box TYP 85 - 95%Electro Hydraulic TYP 60 - 70%Diesel Hydraulic TYP 60 - 70%

Exact figures depend on individual designs but duty factor and heat dissipation have a large impact onwinch capability.

The following formula gives a close approximation of the length of wire rope that can be spooled onto adrum:

L =w x h

4 Dd

Where:L = the length of line which will fit drum (feet)

h = height of wire rope on drum when full (in)d = diameter of drum (in)w = width of the drum (in)D = diameter of wire rope (in)

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Hydraulic Motor Formulas

Definitions:PSI = Pounds per square inch of hydraulic pressureCID = Cubic inch displacement of your hydraulic motorRPM = Revolutions per minute of your hydraulic motor

GPM = Gallons per minute of hydraulic fluid from your hydraulic pumpHP = Horsepower

Torque =PSI * CID

6.28

GPM =CID * RPM

231

HP =Torque * RPM

63025

Electric motor starting requirements

The maximum Horsepower of an electric motor you can start at one time with a generator is 2/3 of thegenerators KW.

Example:

A 100KW generator can start up to a 66 HP motor. Although you can start additional smaller motorsafter the largest motor is running.