Hammer Crusher

A hammer crusher, sometimes called hammer mill, is a machine used to shred or crush materials into smaller pieces. The basic design of machines of this type involve a rotating shaft to which free-swinging hammers are attached. This assembly is enclosed by a drum which holds the material to be pulverized. A hopper feeds the source material into the drum. The hammers gradually break up the material until it is small enough to pass through a screen with openings corresponding to the desired particle size.

Hammer crusher is used for crushing raw materials such as limestone, marl, sandstone, gypsum, coal, etc. The compression strength of the materials to be crushed by hammer crusher is less than 150MPa. The single stage hammer crusher can crush the ore block into the required granularity at a time. It can replace traditional two-stage crusher and help to simplify process flow and save infrastructure investment and production costs.

The hammer crushers breaks rocks by impacting the rock with hammers that are fixed upon the outer edge of a spinning rotor. The practical use of hammer crushers is limited to soft materials and non-abrasive materials such as limestone, phosphate, gypsum and weathered shales.

Benefits and Features of Hammer Crusher

1. Big reduction ratio: maximum feeding size is 1.3-1.5m; 3-150mm of discharging size.

2. High fineness of discharging size: favorable shape with aggregate, the powdery material is no more than 20%.

3. Simple process: the two or three stage crushing is reduced into single stage.

4. Economical: small capacity of matched motor, which greatly reduces the production cost.

Working Principle of Hammer Mill

The electromotor drives the rotor to rotate with high speed in the crushing chamber. The materials are fed into the machine from the upper feeding mouth and are crushed under the hitting, impacting, cutting and grinding of the hammer which is moving with high speed. On the bottom of the rotor, there is sieve plate and the crushed materials that is smaller than the screen size are discharged from the sieve plate, and the coarse particles bigger than the screen size are retained on the sieve plate to be hit and ground again by the hammer and finally be discharged from the machine from the sieve plate.