1, what is a crusher? Crushers are usually used in mining industry. Crusher refers to the crushing machinery with particle size greater than 3 mm, which accounts for more than 50% of the total output. Crushing operations are often divided into coarse crushing, medium crushing and fine crushing according to the particle size of incoming and outgoing materials. Crushers are widely used in crushing operations in mining, smelting, building materials, highways, railways, water conservancy, chemical industry and other industries. 2. What kinds of girls are there? Commonly used crushers include jaw crusher, impact crusher, PCL direct impact crusher, rotary crusher, cone crusher, roller crusher, hammer crusher and vertical shaft impact crusher. General crushers are divided into jaw crushers, hammer crushers, impact crushers, vertical crushers, sand makers (also known as crushers), single-stage hammer crushers, ring hammer crushers, cone crushers and compound pendulum jaw crushers. Jaw crusher is a crushing machine that uses the squeezing and bending effects of two jaws on materials to coarsely or moderately crush materials with various hardness. Its crushing mechanism consists of a fixed jaw and a movable jaw. When the two jaws approach, the material is crushed, and when the two jaws leave, the material smaller than the discharge port is discharged from the bottom. Its crushing action is intermittent. The crusher has simple structure and reliable operation, and can crush hard materials, which is widely used in mineral processing, building materials, silicates, ceramics and other industries. The working principle of cone crusher is the same as that of rotary crusher, but it is only suitable for crushers with medium crushing or fine crushing operations. Generally speaking, the uniformity of discharged particle size in middle crushing and fine crushing operations is higher than that required in coarse crushing operations. Therefore, it is necessary to set a parallel zone at the lower part of the crushing cavity, and at the same time, it is necessary to speed up the rotation speed of the crushing cone, so that the materials can be squeezed in the parallel zone for many times. The crushing of medium and fine crushing operation is greater than that of coarse crushing operation, so the loose volume after crushing is greatly increased. In order to prevent the crushing cavity from being blocked, it is necessary to increase the total discharge section by increasing the diameter of the lower part of the crushing cone without increasing the discharge port, so as to ensure the required discharge granularity. The discharge port of cone crusher is small, and it is more likely to cause accidents when the non-crushed materials are mixed into the feed. Because the medium and fine crushing operation requires strict discharge granularity, the discharge port must be adjusted in time after the liner is worn, so the safety and adjustment device of the cone crusher is more necessary than the coarse crushing operation. Roller crusher is a machine that uses the friction of roller surface to bite the material into the crushing area, so that it is crushed by extrusion or splitting. When it is used for coarse crushing or needs to improve the crushing ratio, teeth or grooves are often made on the roller surface to increase the splitting effect. Roller crushers are usually divided into single roller, double roller and multi-roller crushers according to the number of rollers, which are suitable for coarse crushing, medium crushing or fine crushing of coal, limestone, cement clinker and feldspar. Hammer crusher is a crusher that uses the high-speed impact of hammer head to crush and finely divide materials. The hammer is hinged on the high-speed rotating rotor, and the lower part of the machine body is equipped with a grate to control the discharging granularity. The materials sent to the crusher are firstly crushed by the impact of a high-speed hammer, and at the same time, kinetic energy is obtained, and the crushing plate flying to the inner wall of the casing at high speed is crushed again. The material smaller than the grate gap is discharged from the machine, and the material larger than the grate gap is impacted and ground by the hammer again on the grate bar until it is smaller than the grate gap. Hammer crusher has the advantages of large crushing ratio, uniform discharging particle size, less over-crushed materials and low energy consumption. However, due to the rapid wear of hammer head, its application in hard material crushing is limited; In addition, because the grate is afraid of blockage, it is not suitable for crushing materials and clay with high humidity. This crusher is usually used to crush brittle materials, such as limestone, shale, coal, gypsum, chalk and so on. It is an improvement of the hammer crusher to replace the hammer head of the hammer crusher with a ring crusher with a steel ring. It uses the comprehensive action of high-speed impact and low-speed rolling to crush materials, so it can obtain finer products, which are mainly used to crush coal used in power plants, but can also be used to crush gypsum, salt chemical raw materials and some medium-hard materials. Impact crusher is a machine that uses the high-speed impact of plate hammer and the rebound of impact plate to crush materials through repeated impact. The plate hammer is fixed on the high-speed rotating rotor, and a plurality of impact plates are arranged at different angles along the crushing cavity. When the material enters the action area of the plate hammer, it is first impacted by the plate hammer, and it is broken for the first time. At the same time, it gains kinetic energy and rushes to the impact plate at high speed. After the material collides with the impact plate and breaks again, it is bounced back to the action area of the plate hammer and is impacted by the plate hammer again. Repeat this process until it is crushed into the required particle size and discharged from the machine. Compared with the hammer crusher, the impact crusher has a larger crushing ratio and can make full use of the high-speed impact energy of the whole rotor. However, because the plate hammer is easy to wear, its application in crushing hard materials is also limited. Usually used for coarse crushing, medium crushing or fine crushing of brittle materials such as limestone, coal, calcium carbide, timely, dolomite, iron sulfide, gypsum and chemical raw materials. Straight-through impact crusher (sand making machine): This product is suitable for crushing and shaping soft or medium hard and extremely hard materials, and is widely used in all kinds of ores, cement, refractories, bauxite clinker, emery, glass raw materials, machine-made building sand, stone and various metallurgical slag, especially for high-hard, ultra-hard and wear-resistant materials such as silicon carbide, emery, sintered bauxite and fine sand. The working principle of straight-through impact crusher (sand making machine) is that the material vertically falls into the impeller rotating at high speed from the upper part of the machine, and under the action of high-speed centrifugal force, it collides with another part of the material distributed around the impeller in an umbrella shape at high speed. After the materials collide with each other, they will collide and rub with each other for many times between the impeller and the casing, and then they will be directly discharged from the lower part to form a closed loop for many times, which is controlled by the screening equipment to achieve the required finished product granularity. 3. What are the uses of the pulverizer? Crushers are widely used in crushing operations in mining, smelting, building materials, highways, railways, water conservancy, chemical industry and other industries. 4. How to choose the crusher manufacturer? First of all, it depends on the strength, reputation and scale of the manufacturer; Secondly, it depends on the product quality, technical level and maturity of the manufacturer. Thirdly, it depends on the manufacturer's customer's production place, which is the most convincing. Finally, we must shop around, carefully examine and choose carefully. For more information, please refer to the website of Liming Road and Bridge Heavy Industry Co., Ltd.: