Synchronous belt is one of important transmission mechanism in mechanical transmission, and with the constant improvement of the industrial technology level and equipment fine mi, lightweight, functional and personalized requirements, belt has been to high precision, high speed, high power, high rate of xiao, high reliability, long life, such as direction, the scope of its application is more and more widely, the form of transmission is also becoming more and more. As main body in the belt transmission parts, transmission belt a shift from the original parts to function, its breed specification more and more diversified, the traditional common wrapped V belt and ordinary flat belt developed narrow V belt, V belt, wide transmitte V belt, wedge belt, synchronous belt, etc. The belt has been widely used in automobiles, machinery, textile, home appliances, light industry, agricultural machinery and other fields, in our daily life plays a very important role. With the belt, on the other hand, species diversity, using performance standards continue to improve, in the production of transmission belt has been adopted the new material, new technology and new technology, also is becoming more and more advanced production equipment and testing means.