The utility model discloses a practical belt tightener, cramp bar support including a pair of parallel?distribution, the tail end of a pair of cramp bar support is equipped with the main lead screw that extends to advance in its support respectively, be connected with I cramp bar of a belt between a pair of main lead screw tip, II cramp bars of a fixedly connected with belt between the front end tip of a pair of cramp bar support, I cramp bar of belt and belt II cramp bars are centre gripping belt I and belt II respectively, I cramp bar of belt rotates through main lead screw and drives I cramp bar of belt along a pair of cramp bar support removal, make the belt clamp contact of belt I and II tip of belt, and detain together. The equipment that the device had solved the belt transport class does not lead to operating efficiency greatly reduced's phenomenon because of there being professional auxiliary worker utensil when changing. This simple structure, convenient operation, not only improve equipment maintenance efficiency has also improved safety work coefficient simultaneously.