V-Belt Basics
Means of Power Transmission
• V-Belts
• Chains
• Gears
• Timing Belts
V-Belts and V-Belt Drives
The function of a belt is to simply transfer rotation from the powered pulley to one or more driven pulleys. The belt must be designed and manufactured to transfer this torque efficiently and reliably.
V-Belts and V-Belt Drives
•V-Belts have been around since the early 20th century
V-Belts and V-Belt Drives
•V-Belts work using the principle of the ”wedge”
V-Belts and V-Belt Drives
•V-Belts are available in thousands of sizes and configurations
•Primary function is to transmit power from a primary source (motor) to a secondary “driven” unit
V-Belt Characteristics•Less expensive than other forms of power transmission•Start, stop and run smoothly•Operate noiselessly and without lubrication•Absorb objectionable and harmful vibrations•Clean and requires minimum maintenance•Rugged and long lasting•Provide a wide selection of speed ranges•Cover an extremely wide horsepower range•Easy to install and simple to replace•Relatively unaffected by moisture, abrasive dusts, or extreme
variations in temperature
V-Belt Drive Terms
V-Belt Construction
Compression Section
Tension SectionTensile Members
Types of Belts•Classical or Multiple V-Belts•Fractional Horse-Power or Light Duty V-Belts•Narrow or Wedge Multiple V-Belts•Double Angle or Serpentine V-Belts•Banded Belts•V-Ribbed Belts•Variable Speed Belts•Trapezoidal Synchronous or Timing Belts•High Torque Synchronous belts•Specialty Type Belting
•V-Belt - works on the principle of the wedge and relies on tension to create friction on the sidewall of the sheave to transmit power
•Synchronous or timing belt - relies on accurate and smooth meshing of the teeth on the belt with the grooves of the sprocket
Two Major Belt Categories
•Wrapped Molded which has a fabric cover and is molded into a V-shape
•Raw Edge which is cured and then cut into a V-shape
Two Major Types of V-Belts
Wrapped V-Belt Construction
•1. Protective fabric cover impregnated with rubber
•2. Tension Section - synthetic rubber compounded to stretch as belt bends
•3. Cords - synthetic fiber cords carry the power and minimise stretch
•4. Compression Section - synthetic rubber compound to support cords evenly and compress as belt bends
Raw Edge V-Belt Construction
•1. Tension Section - specially woven stress-relived fabric
•2. Cords - synthetic high modulus cord to carry high loads with minimal stretch
•3. Compression Section - Stiflex rubber compound and precision molded cogs increase flexibility and supports cords
•4. Raw Edge Side Walls - provide uniform anti-slip surface, greater flexibility and allow more cord
Advantages Raw Edge vs. Wrapped
•Performs up to 4%more efficiently
•Generates less heatbuild up
•Allows smaller pulley diameters
•Increased power ratings
•Provides longer life
Classical or Multiple V-Belts
Gold Ribbon Cog Belt
Raw Edge ClassicalPremium Product
Super Blue Ribbon
Wrapped Molded ClassicalHighest Volume Belt
Super II V-Belts
Raw Edge Classical Extreme Duty
Fractional HorsepowerLight-Duty V-Belts
Durapower FHPStandard FHP Line
XDV Xtra Duty V-BeltPremium Lawn/Garden Line
Durapower II FHPRaw Edge FHP Line
Narrow or Wedge Multiple Belts
Power Wedge Cog V-BeltsRaw Edge
Increased HP Capability
Super Power Wedge V-BeltsWrapped Molded
Increased HP Capability
Banded Belts
Gold Ribbon Cog-BandRaw Edge
Premium Product
Super Vee-BandWrapped Molded
Standard product
Wedge-Band Cog-Band
Raw EdgeHigher HP
Wedge-Band Wrapped Wrapped Molded
Higher HP
Synchronous Belts
RPP Panther RPP Plus Dual RPP
Synchro-Cog Timing Belt Synchro-Cog Dual Timing Belt
Specialty Belts
Dry Can BeltingDouble Angle V-Belts
Thoro-Twist V-Belts