Study of the Eccentric-striking Reasons in Hammer Mills and Design New Types of Hammer Sheets

摘要

The high-speed photography method has shown that one of reasons to affect the efficiency of hammer mills is the eccentric - striking during particles crushed by hammer sheets in a mill. A study about the reasons of the eccentric - striking was carried out in this paper. There were 3 new types of hammer-sheets, which are the arc, the steamline and sharp angular sheets,developed by the authors. A comparison of those new sheets and the standard sheet used currently showed that the productivity per unit power consumed using the arc,the sharp angular sheets and the standard sheets used currently were 140. 6,150. 0 and 120. 8 kg/unit respectively; and the power consumptions were 7. 11,6. 66and 8. 27 unit/tone respectively. Based on the results, the productivities per kW·h were increased 19. 8 and 29. 2 kg;and the energies can be saved 1. 16 and 1. 61 unit to grind one tone particles using the sharp angular and the arc new sheets respectively. It showed obviously that the grinding efficiency increased, the energy consumption decreased and the phenomenon of the eccentric - striking was minimized using the new types of sheets in hammer mills.