为了提高φ3.2×3.1米格子型球磨机的处理量和磨矿细度,我厂于1979年元月将φ3.2×3.1米球磨机加长0.9米,改制成令3.2×4.0米球磨机。经过近两年的生产实践表明:φ3.2×4.0米球磨机运转良好,各部件均没有发现异常现象。从经济效果来比较,1979年φ3.2×4.0米球磨机台效比φ3.2×3.工米球磨机提高2.7吨/ In order to improve φ3.2 × 3.1 m grid-type ball mill handling capacity and grinding fineness, I plant in January 1979 φ3.2 × 3.1 m ball mill lengthened 0.9 meters, transformed into 3.2 × 4.0 m ball mill. After nearly two years of production practice shows that: φ3.2 × 4.0 m ball mill is running well, all the components were found no abnormalities. From economic results to compare, φ3.2 × 4.0 meters in 1979 table efficiency than φ3.2 × 3. Mill meters increase 2.7 tons /