Introduction & working principle
Impact crusher working principle is mainly by the high speed rotation hammer bars to impact the materials, when material falls tangentially on to a rotor, running at 250-500 rpm, receiving a glancing impulse, which sends it spinning towards the impact plates.
The fractured pieces which can pass between the clearances of the rotor and breaker plate enter a second chamber created by another breaker plate,where the clearance is smaller, and then into a third smaller chamber.
Impact crusher gives a much better control of product size because there is less attrition. The product shape is much more easily controlled and energy is saved by the removal of particles once they have reached the size required. A great advantage in quarrying is in the fact that the impact crusher produces very good cubic products.
Impact crusher structures
Impact Crusher is mainly composed of rotor, impact frame, main frame and transmission parts. Rotor is the key part of the impact crusher. The rotor frame is made of welded steel plate, and the hammer plates are fixed in the correct position, and the axial limiting device can effectively prevent the hammer plates from shifting.
The impact crusher is equipped with two impact frames, one at the front and the other at the back, both of them are self-supporting and suspended, each of them is individually supported on the crusher frame. The clearance between the impact frame and the rotor can be adjusted by the suspension bolts. The exchangeable impact liners are fixed on the impact frame with a tilt-up structure, and the impact liners can be replaced from the place where it is worn to the place where it is less worn.
The specification of the impact crusher is expressed by the rotor diameter D (actually the diameter of the circumference drawn on the end of the plate hammer) X rotor length L. For example, Φ1250×1000 single rotor impact crusher, indicates a rotor diameter of 1250 mm and a rotor length of 1000 mm.
1. It can crush ores and rocks with compressive strength of 250MPa.
2. Large crushing ratio, close to 20, simplifies the crushing process.
3. Low energy consumption, usually about 1kW/t per unit output, which reduces the production cost.
4. The product particle size is cubic, with less than 8 % of flakes, which can improve the quality of concrete.
5. It has the advantage of selective crushing, and can obtain more sand grade products.
6. It has excellent pass iron performance, and the main machine will not be damaged when non-breakable objects enter the crushing cavity.
7. Simple and reasonable structure of the whole product, easy to maintain and repair.
8. No significant unbalance vibration during working, no need heavy foundations.
Particle size & curve
The cubic shape of the finished granule is a significant advantage of the impact crusher. The excellent cubic shape of the aggregate particle size can improve the quality of concrete. Some special construction, such as airports, highways, water conservancy, etc., have high requirements for the flake content of the aggregate, which is less than 8%, the particle cubic size produced by the impact crusher can fully meet the high standards.
Highway construction aggregate(basalt) chemical composition
Note: this basalt compressive strength 266.7 MPa on average
Flaky particles content in the aggregate
Stone crusher plant process diagram with jaw crusher and impact crusher as follows, the whole process is simple and reasonable, it obtains excellent cubic shape gravels.
Impact crusher curve as follows
For impact crusher, its wear-resistant material( mainly hammer plate, breaker plate) is crucial, Deya Machinery has developed a special high chromium cast iron material as the base material of the hammer plate, which has high hardness, high impact toughness and high wear resistance, comparing with the hammer plates imported from Germany, our wearing parts has reached high quality level.