Хонинговальные головки

In Cornwall in 1804, John Taylor at Wheal Travistock set up two discarded pump barrels in parallel (Barton 1961) as horizontal rolls to crush copper and tin ores for concentra­tion by gravity. This experimental crusher, which became known as “Cornish rolls,” was driven by a steam engine (Figure 5.8). The rolls were only one of […]

Figure 6.8 shows a ring-roller mill invented by F. E. Huntington in 1883 to grind gold­bearing quartz ores to liberate the gold before amalgamating it on tables. The Huntington mill was a roller mill similar to an arrastra, but centrifugal force, instead of gravity, drove its grinding action. It had three suspended flat rollers that […]

By 1890, 100 Krupp-Grusonwerk tumbling mills were operating in cement plants, and other companies were manufacturing them. One company that contributed much to the technology of tumbling mills was F. L. Smidth and Co. of Denmark. This company had been established as a one-man consulting engineering business by Frederik Laessoe FIGURE 7.5 Transporting an early […]

Mills and the materials used to build mills have to withstand the high stresses involved in each revolution of the mill with a complete reversal from maximum compression to maximum tension and back again. Mill design required a complete understanding of the stresses involved in one rotation of the mill. As the size of tumbling […]

The classification of very fine particles is carried out in many industries in air rather than water to avoid problems with chemical reactions of particles with water and with separa­tion of ultrafine particles from water and drying them. Some of the disadvantages of dry classification are that it requires ducts and processing equipment that are […]

The prospects for the future of size reduction cannot be precisely established. The his­tory and the questions facing those industries that use the technology, however, indicate the areas requiring study. Technology has always stepped up to meet the demand for size reduction. Educational and research facilities have been created to teach and to search for […]