Ball mill bull gear

This paper elaborates on the ball mill bull gear, a key transmission component that meshes with the pinion to drive the cylinder at low speed (15-30 r/min) under heavy loads (torque up to millions of N·m), with materials like 45# steel, 42CrMo alloy steel, and ZG35CrMo cast steel for different sizes, and split structures (2-4 segments) commonly used for large gears (diameter ≥3m) for easy transportation and installation. It details the manufacturing process of 42CrMo split gears, including blank preparation (forging/cutting), rough machining with assembly, quenching and tempering, finish machining (precision gear hobbing, grinding), and surface treatment. Additionally, it outlines comprehensive inspection procedures covering raw materials (chemical composition, forging quality), heat treatment (hardness, metallographic structure), tooth profile accuracy (pitch deviation, radial runout), and final product tests (assembly accuracy, meshing performance). These ensure the bull gear meets strength, toughness, and precision requirements, enabling stable transmission with efficiency ≥94% and a service life of 3-5 years.