A ball mill, a type of grinder, is a cylindrical device used in grinding (or mixing) materials like ores, chemicals, ceramic raw materials and paints. Ball mills rotate around a horizontal axis, partially filled with the material to be ground plus the grinding medium. Different materials are used as media, including ceramic balls, flint pebbles and stainless steel balls. An internal cascading effect reduces the material to a fine powder.
Industrial ball mills can operate continuously, fed at one end and discharged at the other end. Large to medium-sized ball mills are mechanically rotated on their axis, but small ones normally consist of a cylindrical capped container that sits on two drive shafts (pulleys and belts are used to transmit rotary motion). A rock tumbler functions on the same principle. Ball mills are also used in pyrotechnics and the manufacture of black powder, but cannot be used in the preparation of some pyrotechnic mixtures such as flash powder because of their sensitivity to impact. High-quality ball mills are potentially expensive and can grind mixture particles to as small as 5 nm, enormously increasing surface area and reaction rates. The grinding works on the principle of critical speed. The critical speed can be understood as that speed after which the steel balls (which are responsible for the grinding of particles) start rotating along the direction of the cylindrical device; thus causing no further grinding.
The ball mill is a horizontal tubular rotating device, with two stock bins. It is of grid type and is gear-driven. The materials are sent spirally and evenly into the first stock bin along the hollow axis by feeding device. The stock bin has ladder scaleboard or ripple scaleboard, and has steel balls of different specifications. The rotating tank causes centrifugal force. Under the function of centrifugal force, the steel ball is carried to certain height and falls onto the materials for grinding. After being coarsely grinded in the first stock bin, the materials then enter into the second stock bin (with steel ball and scaleboard) for further grinding. Lastly, the powder is discharged from the grid plate to complete the grinding.china jaw crusher: http://www.hx-china.com/1.html
来自 “ ITPUB博客 ” ，链接：http://blog.itpub.net/29264349/viewspace-774743/，如需转载，请注明出处，否则将追究法律责任。