Ball Mill End Liners | Feed Discharge Heads | ATF

Ball Mill End Liners: Head Protection and Material Flow

End liners (also called head liners) protect the mill heads at both the feed and discharge ends from impact and abrasive wear while directing material flow through the grinding chamber. Feed-end liners guide incoming ore from the trunnion into the active grinding zone, and their profile geometry influences how quickly fresh feed is incorporated into the ball charge. Discharge-end liners work in conjunction with the discharge system—whether overflow, grate, or peripheral—to control product exit rate and prevent short-circuiting of unground material. Both positions must withstand sustained impact from the tumbling ball charge at speeds of 70–78% of critical, combined with continuous sliding abrasion from ore particles. ATF manufactures end liners from ASTM A532 chrome-moly steel (325–400 BHN), high-chrome white iron (600+ BHN), and natural rubber (60–70 Shore A), with each piece dimensionally verified against the specific mill head profile.

End liner design directly affects grinding efficiency through its influence on material flow patterns and charge dynamics near the mill heads. Poorly designed end liners create dead zones where material accumulates without effective grinding, reducing throughput and increasing specific energy consumption. ATF engineers end liners matched to your specific mill configuration, trunnion diameter, discharge system type, and grinding circuit objectives. Finite element analysis ensures each end liner withstands the cyclic impact loads experienced during mill rotation, while profile optimization promotes efficient material circulation. End liners are typically supplied in segmented configurations of 6 to 12 pieces per head, with integral lifting lugs and precisely located bolt holes for safe handling and rapid installation during scheduled relining shutdowns.