<p>A crushing chamber is formed between a concave liner and a mantle liner. The concave liner has a first area surface having a length of T to 2ROOT 2T; a second and a third area surface; which surfaces are gradually inclined from the side of the inlet for the crushing chamber. The mantle liner has a first tapered surface having a length of greater than T, a cross angle of less than 20 DEG and an inclination angle of greater than 60 DEG ; a second tapered surface having a length of greater than 0.5T and a cross angle of 5 DEG to 10 DEG ; and a third tapered surface having an inclination angle of 45 DEG to 50 DEG . The area surfaces as well as the tapered surfaces are continuously arranged in a curvilinear manner. The shapes enhance the throughput of goods in a good fine-crushing performance, reducing the uneven abrasion due to the action. <IMAGE></p>
