Fatigue Design Of Large Shell Supported Ball Mills With Aerofall Hydrodynamic Bearings And Gearless Drives ? Introduction

This paper presents some techniques and data required to design large ball mills. The advent of larger size mills leads to consideration of the gearless drive as a practical solution to utilize large horsepowwers. The particular shell structure under consideration is subjected to thermal as well as magnetic loads. The magnitude of the inertia, magnetic and shell temperature characteristics have a very significant effect on the design and performance of the hydrodynamic pivoted shoe bearing. Particularly since these bearings have lower frictional resistance properties than hydrostatic trunnion tee rings. The structure of the mill is designed for long life. Parameters involved with the fatigue life of the structure are discussed together with some of the more important aspects of the design.