| 摘要 |
963,088. Roller mills. POLSKA AKADEMIA NAUK INSTYTUT BADAN JADROWYCH. Aug. 21, 1962 [Aug. 26, 1961], No. 32107/62. Heading B2A. Hard granular material, such as quartz sand is ground by feeding it between rolls 1, 3 of a mill at a velocity equal to their peripheral velocity and at a rate not exceeding their throughput capacity, the material being supplied in the forn. of a flat stream having a width not exceeding the working length of the rolls and a thickness of the order of the grain size before it is ground. As shown, the material is fed to the rolls by gravity through a nozzle 6 from a hopper 5 disposed at the height necessary for the material to attain a velocity corresponding to that of the rolls, the roll 3 being adjustable and one or both driven; alternatively the material may be fed mechanically or by a gas or liquid stream. The mill may be enclosed in a gas-tight housing and operated in an atmosphere of inert gas or a vacuum. Material may be ground to progressively smaller sizes in three superposed stages through which the material successively passes. All the stages resemble the roll arrangement described above, the first two stages each consisting of two coacting rolls and the third stage of four pairs of coacting rolls disposed in a parallel arrangement. |
