Abstract：Impact-crushing velocity is the principal parameter influencing lump-coal impact-crushing effect. When lump coal impacted the rigid plate, the contact stress was presented based on piecewise plastic-deformation model. The impact velocity crushing lump coal into a certain size was derived theoretically by crack hypothesis and energy conservation principle. The experiment fitting formula was proposed out through lump-coal impact-crushing experiments, so the theoretical modified formula did. Compared with experimental results, 88% fitting values’ errors are less than 10%, while 85% theoretical modified values less than 20%. The analysis results shows that the fitting formula are too complex to engineering application, the theoretical modified formula can meet the accuracy for primary crushing and may be as theoretical selection rules for impact-crushing velocity.
2011, Vol. 30 
