First, the structure: 1) Counterattack:
The function of the counterattack is to withstand the impact of the material hit by the hammer, so that the material is broken by the impact, and the material after the impact is broken back to the impact zone, and the impact crushing is performed again to obtain the required product granularity. There are many forms of counterattacks, mainly in the form of a line shape and an arc shape. The line-shaped counter-attack surface enables the material at each point of the counterattack to be impacted in an approximately vertical direction, so that the best crushing effect can be obtained. The arc-shaped counter-attack surface enables the block to rebound from the counter-attack plate, forming a severe impact crushing zone in the center of the circle to increase the free impact crushing effect of the material. The counterattack plate is generally welded by steel plates. The counter-attack surface is provided with a wear-resistant lining, but it can also be composed of a counter-roller or a crepe plate. The counter-attack surface with quilting has a small content of fine-grained products, and the production capacity of the equipment can be improved, and the power consumption is saved. However, there are defects such as complicated structure, difficulty in replacement after the impact surface is worn, and rapid wear. The rotor of the impact crusher is mostly made of integral cast steel. The structure is sturdy and durable, and it is easy to install the hammer. Its quality is large and can meet the crushing requirements. The rotors of small and light impact crushers can also be welded from steel plates.
2) Plate hammer:
The shape of the hammer is closely related to the fastening method and working load. The design of the hammer should meet the requirements of reliable work, easy loading and unloading, and improved utilization of the metal of the hammer. Plate hammers are generally made of high chromium cast iron, high manganese steel and other wear resistant alloy steels. The hammer has many shapes, such as a long strip, a T shape, an S shape, a work shape, an axe shape, and a grooved shape, and is now generally elongated. The impact crusher is a new type of high-efficiency crushing equipment. It is characterized by small volume, simple structure, large crushing ratio (up to 40), low energy consumption, large production capacity, uniform product size and selectivity. The role of crushing is a promising device. However, its biggest drawback is that the hammer and the counterattack are particularly prone to wear, especially the hard ore that is broken, and the wear is more serious and needs to be replaced frequently. At present, due to the appearance of some wear-resistant materials, it has been applied in some metal concentrators.
Advantages: This series of products can handle materials with side lengths of 100-500 mm, with compressive strength up to 350 MPa, with large crushing ratio and cubic particles after crushing.
Second, the working principle:
The stone material falls directly from the upper part of the machine into the high-speed rotating turntable; under the action of high-speed centrifugal force, the other part is divided into the flying stone around the turntable by the umbrella type to produce high-speed collision and high-density crushing. After the stone hits each other, the stone will A vortex motion is formed between the turntable and the casing to cause multiple blows, friction, and pulverization, and is discharged straight from the lower portion. The closed loop is formed multiple times and controlled by the screening device to achieve the required particle size. The structure of the impact crusher, the material block is fed from the feed port, and in order to prevent the material block from flying out during the crushing, a chain curtain is arranged in the feeding direction of the feed port. The fed block falls on the top of the stringer, and the small block falls through the quilting to the lower part of the casing, and the bulk material slides along the screen surface onto the rotor. A plate hammer having a certain height is fixedly mounted on the circumference of the rotor, and the rotor is rotated by the motor through the V-belt belt at a high speed. The block falling on the rotor is impacted by a high-speed rotating plate hammer. After obtaining kinetic energy, it hits the counter-attack plate at a high speed, and then bounces back from the counter-attack plate, and collides with the material thrown by the rotor in the crushing zone. The space formed by the strip screen, the rotor, the counterattack plate and the chain curtain is called the first impact zone; the space formed between the counterattack plate and the rotor is the second impact zone. After the materials are crushed by mutual impact in the first impact zone, they are then subjected to impact pulverization again after entering the second impact zone. The broken material is discharged through the discharge port at the lower part of the casing. One end of the counterattack is suspended from the casing by a live chain, and the other end is fixed by an adjusting bolt. When a large piece of material or a difficult-to-break object is sandwiched between the rotor and the counter-attack plate, the counter-attack plate is subjected to a large pressure to cause the counter-attack to move backward, and the gap is increased to allow the difficult-to-break material to pass without causing damage to the rotor. Then, the counterattack plate returns to its original position under the action of its own weight, and serves as a protection device for the crusher.