Gantry crane Zhidongshiling failure analysis

Rotate work, Zhidongshiling disintegration of rotating worm gear box can be found in the limit torque limiter does not reach its design slip resistance moment when the malfunction.
(1) Analysis: actual operation starts rotating gantry crane, the brake is very frequent, so that the friction torque limiter plate and the worm gear sets often produce relative movement between the cone and wear, rubbing up and down along the worm taper gradually move closer to the plate. Put the worm, the next junction of cone angle, and its diameter is less than the friction disc small end diameter, and thus in the worm was inside the cone grind annular boss, when pressed by the pallet jacks force generated by the spring on the conical surface and the annular projection plane two parts together to bear. When the annular projection plane withstand clamping force dominates, due to the short arm boss plane rotation and the friction surface is small, so that the friction torque is reduced, and less than the original design moment occurs when these failures.
(2) exclusion method: the disintegration of the rotating worm gear box, remove the worm, the worm within the annular projection on the cone car to make the worm gear sets at the intersection of two cone is a transitional cylindrical surface, and the cylindrical surface small end diameter slightly larger than the diameter of the friction plate.