V-Belt Service Factors Table Chart

V and Flat Belt Design and Engineering Data

Service Factors for V-Belts

The selection of a V-belt drive for any application should be based on the nature of the load and the type of driving unit. Service Factors for different kinds of driven machines combined with different types of driving units are shown in the table below. The driven machines are representative examples only. Select a driven machine whose load characteristics most closely ressemble those of the machine being considered. Multiply the rated motor power or power demand of the driven unit by the selected service factor to obtain the “design power”

TYPE OF DRIVEN MACHINES	Type of Driving Device
	AC Motors: Normal Torque, Squirrel Cage, Synchronous and Split Phase. DC Motors: Shunt Wound, Multiple Cylinder Internal Combustion Engines.			AC Motors: High Torque, High Split, Repulsion-Induction, Single Phase Series Wound and Compound Wound, Single Cylinder Internal Combustion Engines. Line Shafts. Clutches
	Intermittent Service (3-5 Hours Daily or Seasonal)	Normal Service (8-10 Hours Daily	Continuous Service (16-24 Hours Daily)	Intermittent Service (3-5 Hours Daily or Seasonal)	Normal Service (8-10 Hours Daily)	Continuous Service (16-24 Hours Daily)
Agitators for Liquids Blowers and Exhausters Centrifugal Pumps and Compressors Fans up to 10 HP Light Duty Conveyors	1.0	1.1	1.2	1.1	1.2	1.3
Belt Conveyor for Sand, Grain, etc. Dough Mixers Fans Over 10 HP Generators Line Shafts Laundry Machinery Machine Tools Punches-Presses-Shears Printing Machinery Positive Displacement Rotary Pumps Revolving and Vibrating Screens	1.1	1.2	1.3	1.2	1.3	1.4
Brick Machinery Bucket Elevators Exciters Piston Compressors Conveyors (Drag-Pan-Screw) Hammer Mills Paper Mill Beaters Piston Pumps Positive Displacement Blowers Pulverizers Saw Mill and Woodworking Machinery Textile Machinery	1.2	1.3	1.4	1.4	1.5	1.6
Crushers (Gyratory-Jaw-Roll) Mills (Ball-Rod-Tube) Hoists Rubber Calenders-Extruders-Mills	1.3	1.4	1.5	1.5	1.6	1.8