The role of the counterattack board is to withstand the impact of the material hammered by the board hammer, so that the material is broken by impact, and the material after the impact crushing is rebounded back to the impact area, and the impact crushing is performed again to obtain the required product grain size.
There are many types of counterattack boards, mainly broken lines and arcs. The zigzag counterattack surface can make the material on each point of the counterattack impact in an approximately vertical direction, so the best crushing effect can be obtained. The arc-shaped counter-attack surface can make the block rebound from the counterattack plate and form a fierce impact crush zone in the center area to increase the free impact crushing effect of the material.
Counterattack plates are generally welded with steel plates. The counter surface is equipped with a wear-resistant liner, but it can also be composed of a counter roll or a slat. With a counterattack with quilted seams, the product has less fine-grained content, crusher equipment production capacity can be improved, and power consumption can be saved. However, there are disadvantages such as complex structure, difficulty in replacing the counterface after wear, and quick wear.
Most of the rotors of the impact crusher are made of cast steel. The structure is sturdy and durable, and the hammer is easy to install. Its quality is large and it can meet the crushing requirements.
The rotors of small and light impact crushers can also be welded with steel plates.
2) Board 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 handling, and improved metal utilization of the hammer. The hammer is generally made of high-chromium cast iron, high-manganese steel and other wear-resistant alloy steel. The shape of the board hammer is many, such as a long bar, a T-shape, an S-shape, a shape, an axe shape, and a grooved shape. Now it is generally a long strip shape.