Working Principle 
The entire center feeding: Material falls into the feed hopper, then enters the high-speed rotary sling wheel from center feeding hole, which is speeded immediately in the sling wheel. The speed can reach several dozens times of the gravity acceleration. Then it is thrown out from the sling wheel. First, it is crushed with other rebounded material fell freely from the sling wheel. Then both of them are impacted to the material lining( rock to rock) or strike back block( rock to iron), rebounded and stroke to the top of eddy cavity in the inclined-up direction. The it moves along deflection-down, and forms a continuous material curtain with the material form the impellers passage. Just like this, the material is stroke, rubbed, crushed twice or more, then is discharged from the down discharging hole. 
Performance Features
1: Large capacity, stable running.
2: Low consumption of wearing parts.
3: Perfect product shape, suit for sand making and stone reshaping.
4: Thinning oil lubricant and automatic maintenance.
5: Hydraulic device for easy maintenance and operation.

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