Deviation detecting device for crane sling

A deviation detecting device for crane sling relates to the hoisting machinery. The utility model solves the technical problem that the current detecting device is bad in reliability and high in manufacturing cost. The utility model comprises a crane double drum, a pulley shaft, a balance pulley, a steel wire rope and a sling. The steel wire rope is twined via the sling and balance pulley and two ends thereof are fixed on the double drum. The balance pulley can be rotated to the pulley shaft. The utility model is characterized in that an angle sensor is installed at the side of the balance pulley. The utility model is suitable for detecting the sling of the crane. The utility model has the advantages of being low in manufacturing cost and high in detecting reliability.