Forged Ball Mill Pinion Gear for Cement & Mining Grinding Mills

The ball mill pinion is the smaller gear that meshes with the girth gear to drive the mill. Though physically smaller, it works just as hard—every tooth engagement transmits the full mill torque, and the pinion typically completes 5 to 10 times more revolutions than the girth gear. This higher cycle count means pinion teeth experience proportionally more fatigue cycles, making surface hardness and core toughness equally important.

Hanwei manufactures ball mill pinions as both standalone replacements and as part of complete gear sets with our girth gears. Supplying both as a matched pair ensures correct mesh geometry from the start—no field adjustment of center distance or backlash is needed at installation.

Our pinions are machined from forged alloy steel, heat-treated to the specified hardness (up to 380 HB on tooth surfaces), and finish-ground to DIN Grade 6 accuracy on our CNC grinding machines. For high-power mills, we offer carburized and hardened pinions with a deep hard case that resists pitting and spalling under heavy contact stress. A critical but often overlooked detail: pinion shaft extension and keyway dimensions must match the existing gearbox output shaft precisely. Our engineering team verifies these interface dimensions for every order, preventing installation problems that can delay mill restart.

When you need a pinion for an existing girth gear—whether ours or another manufacturer's—we can reverse-engineer the pinion from the girth gear tooth data, ensuring correct module, pressure angle, and helix angle matching.

With 3,000+ drawings in our library, most common mill pinion specifications are already on file. Warranty: 1 year standard, 3 years for special designs. Send us your mill model and gear data for a prompt quotation.