SAG-Mühlen-Bodenplatten | ATF

SAG Mill End Liners: Heavy-Duty Head Protection

SAG mill end liners (head liners) protect the feed and discharge heads from the severe impact loading created by the tumbling charge of run-of-mine ore and large grinding balls weighing 100–150 mm in diameter. The feed-end liner must survive direct impact from large ore chunks—up to 300 mm—entering through the feed trunnion, making it one of the highest-wear positions in the entire mill. The discharge-end liner works in conjunction with the grate system to control product exit while shielding the head from the grinding charge. ATF manufactures SAG mill end liners from chrome-moly steel at 325–450 BHN for applications demanding a balance of wear resistance and toughness, and from austenitic manganese steel (Mn14Cr2, conforming to ASTM A128 Grade C) at 200 BHN initial hardness that work-hardens to 500+ BHN under impact, providing exceptional resistance in extremely high-impact zones.

SAG mill end liners require substantially heavier construction than ball mill equivalents due to the larger charge mass and significantly higher impact energies inherent in primary grinding duty. Section thicknesses typically range from 100 mm to 200 mm—double that of many ball mill end liners—to provide adequate material for both wear allowance and structural integrity. Feed-end designs incorporate deflector features and optimised cone angles to redirect incoming ore into the active grinding zone while distributing impact loads across the full head surface rather than concentrating them on localised areas. Discharge-end designs integrate precisely with grate panels, pebble port assemblies, and pulp lifter channels to ensure smooth material flow and efficient product removal without dead zones. ATF engineers end liner systems matched to each specific SAG mill configuration, using 3D modelling and field performance data to optimise profile geometry, segment count (typically 6–16 pieces per head), and material selection.