A crusher is a crushing machine that produces materials with a particle size greater than 3 mm, accounting for more than 50% of the total material volume. Crushing operations are often divided into coarse crushing, medium crushing and fine crushing according to the size of the feed and discharge particles.
Commonly used crushing machines include jaw crusher, gyratory crusher, cone crusher, roll crusher, hammer crusher and impact crusher.
Jaw crusher
Introduction: Jaw crusher is a crushing machine that uses the squeezing and bending effect of two jaw plates on materials to crush or medium crush materials of various hardness. Its crushing mechanism consists of a fixed jaw plate and a movable jaw plate. When the two jaw plates are close to each other, the material is crushed, and when the two jaw plates are separated, the material blocks smaller than the discharge port are discharged from the bottom. Its crushing action is intermittent. This crusher is widely used in industrial sectors such as mineral processing, building materials, silicates and ceramics due to its simple structure, reliable operation and ability to crush hard materials.
By the 1980s, the feed particle size of large jaw crushers that crush 800 tons of materials per hour had reached about 1800 mm. Commonly used jaw crushers are double toggle plates and single toggle plates. The former has a simple arc swing when working, so it is also called a simple swing jaw crusher; the latter also moves up and down while making an arc swing, so it is also called a complex swing jaw crusher.
The up and down movement of the movable jaw plate of the single-toggle jaw crusher promotes material discharge, and the horizontal stroke of the upper part is greater than that of the lower part, which makes it easy to crush large pieces of material, so its crushing efficiency is higher than that of the double-toggle jaw crusher. Its disadvantages are that the jaw plate wears faster, and the material will be over-crushed, which increases energy consumption. In order to protect the important parts of the machine from damage due to overload, the toggle plate with a simple shape and small size is often designed as a weak link, so that it will deform or break first when the machine is overloaded.
In addition, in order to meet the requirements of different discharge particle sizes and compensate for the wear of the jaw plate, a discharge port adjustment device is also added, usually by adding an adjustment gasket or wedge between the toggle plate seat and the rear frame. However, in order to avoid affecting production due to the replacement of broken parts, hydraulic devices can also be used to achieve insurance and adjustment. Some jaw crushers also directly use hydraulic transmission to drive the movable jaw plate to complete the material crushing action. These two types of jaw crushers using hydraulic transmission devices are often collectively referred to as hydraulic jaw crushers.
Gyratory crushers are large-scale crushing machines that use the gyratory motion of the crushing cone in the cone cavity of the shell to squeeze, split and bend the material, and roughly crush ores or rocks of various hardness. The upper end of the main shaft equipped with the crushing cone is supported in the bushing in the middle of the crossbeam, and its lower end is placed in the eccentric hole of the sleeve. When the sleeve rotates, the crushing cone performs eccentric gyratory motion around the center line of the machine. Its crushing action is continuous, so its working efficiency is higher than that of the jaw crusher. By the early 1970s, large gyratory crushers could process 5,000 tons of material per hour, and the maximum feed diameter could reach 2,000 mm.
