The V-belt DriveAbstract: The v-belt drive are widely used in all kinds of machanics , So to understand and know how to design it is very necessary .The v-belt and the pulley are two most important parts of v-belt drive ,the centre distance ,the diameter of the pulleys and the rpm of the pulleys are the most essential parameters of the v-belt drive . The v-belt drive has a drive pulley and a power take-off pulley , we design their diameters in the basis of speed ratio