Product Description

Allis-Chalmers grinding mills — including large-diameter ball mills and semi-autogenous (SAG) mills — dominated hard-rock mineral processing throughout the mid-20th century. According to publicly filed asbestos litigation records, the trunnion bearings that support these rotating drums allegedly used braided asbestos packing rings to seal against slurry infiltration and lubricant loss. Repacking these seals allegedly disturbed friable fibers inside enclosed mill houses at copper, iron, taconite, and gold concentrators.

Workers Exposed

Taconite mill millwrights on the Mesabi Range, copper concentrator workers in the Southwest, and mill operators nationwide are reported in publicly filed litigation records to have serviced Allis-Chalmers grinding-mill trunnion seals. Mill electricians working around the drive ends and mineral processing plant workers cleaning up shed packing allegedly encountered asbestos fibers during scheduled outages.