What's a stone crusher?
A stone crusher is a type of pulverizer that uses mechanical energy to break blocks of stone, concrete, or other building materials into smaller blocks of a specific grain size.
From very hard stones to soft minerals, crushers can be used for a very wide range of materials，they can be utilized in a variety of applications in industries such as mining industry to reduce the size of ore blocks and facilitate their processing，crushed stones previously used as building materials and demolition, crushing the debris left after the demolition of buildings, roads, bridges, canals and various other structures.
Stone crushers are classified according to the fineness with which they fragment the starting material. There are primary crushing, secondary (intermediate) crushing and Fine (tertiary) crushing. Some production lines may include a single crushing stages，the most common production lines involve at least two or three crushing stages.
1. Primary Crushing
As the first stage during a crushing circuit following extraction from a mine site, primary crushing reduces material to a size and shape which will be handled by the secondary crusher. The duty of the first crusher is to form it possible to move material on a conveyer belt . In most aggregate crushing plants, primary crushing is administered during a jaw crusher, although a gyratory crusher could also be used. If material is definitely crushed and not excessively abrasive, an impression crusher could even be the simplest choice as a primary crusher.
2. Secondary (Intermediate) Crushing
In secondary crushing, reduction ratios become an important consideration. Knowing just how fine you would like your final output to be, along side the feed requirements of your tertiary or final reduction crushing station, will assist you determine what proportion reduction must happen within this stage.
Cone crushers are often placed within the secondary crushing station because they're versatile in terms of feed, closed side setting, speed, and throw. With cone crushers, though, it's essential to work them at consistent choked settings to stay productivity up.
3. Fine (Tertiary) Crushing
In this crushing stage, the standard and quantity of fine products are determined. Quality requirements are often stringent for the ultimate products, especially within the mixture industry. Customer requirements common to both the mixture and mining industries are capacities and quality (fraction/particle size). the mixture industry has additional quality demands like soundness and particle shape (cubicity).
How to choose a right stone crusher?
Choosing the appropriate stone crusher is important for every operation, but how to choose a right stone crusher? There are several characteristics to consider:
1. Type and Hardness of Materials
The type and hardness of materials are the first factors to be considered in the selection of crushing equipment. Different types of materials will have different hardness and structure, which will have the primary limit on the selection of stone crusher. Generally, the greater the hardness, the higher the crushing difficulty coefficient.
2. Material Specification
If the material size is large, jaw crusher can be selected as primary crushing; When the size of stone is small and needs to be composed of stone with certain gradation, combined crushing and screening equipment shall be selected.
3. Humidity of Materials
The water content of the material will also affect the selection of the stone crusher. When the water content is too large, the fine materials will agglomerate or stick to the coarse materials due to the increase of humidity, so as to increase the viscosity of the materials, reduce the ore discharge speed and reduce the productivity. When it is serious, it will even block the ore discharge outlet and affect the normal production.
4. Granulometric Requirement
The incoming and outgoing particle size is used to judge the model and crushing level of the required crushing equipment.
5. Output Requirements
The output requirement is an important index to determine the crushing equipment. The higher the output requirement, the larger the required crushing equipment specification, and the corresponding input and output will increase.
6. Construction Site
The specific situation of the construction site is the most direct factor affecting the selection of crusher equipment, such as the site size of the construction site, the specific placement position of crushing equipment, etc.
These are the main stone crushers on the market:
- Jaw Crusher
- Impact Crusher
- Cone Crusher
- Mobile Crusher
- Sand Making Machine
Jaw crushers are often used as primary crushers and are perhaps the foremost popular crusher worldwide. they're suitable for nearly any sort of material.
Crushing takes place between a stationary jaw plate and a moving jaw plate. The moving jaw plate is mounted on the pitman, which is given a reciprocating motion. Crushing takes place when the pitman moves toward the stationary jaw.
There are two main sorts of jaw crushers – single toggle and double toggle.
The single-toggle jaw crusher features a pitman mounted on an eccentric shaft at the highest . At rock bottom of the assembly, the pitman is held in position by a toggle plate. the mixture of eccentric motion at the highest and rocking motion at rock bottom provides a positive downward thrust throughout the crushing chamber.
The double-toggle crusher has two shafts. One may be a pivot shaft from which the pitman hangs whist the opposite is an eccentric shaft which stimulates the 2 toggle plates. The pitman is given a purely swinging motion toward the stationary jaw.
Single-toggle jaw crushers have better feed acceptance capability than the corresponding double-toggle crushers. Jaw crushers are reliable, robust machines, offering a 6:1 reduction ratio in most materials, and can accommodate hard, abrasive materials.
The impact crusher can handle materials with side length of less than 100-500mm, and has the advantages of high crushing ratio and cubic particles after crushing. The impact crusher is named according to the working principle, that is, it uses the principle of impact crushing to crush materials. It is a kind of crusher equipment finer than the jaw crusher. It is mainly used for fine crushing operation in the stone production line and cooperates with the jaw crusher.
The bearing seat of impact crusher adopts integral cast steel structure to ensure the stability of machine operation; Larger size bearings are selected to make them have higher bearing capacity. Two chamber crushing can simplify the process flow in coarse and medium crushing operation; Three chamber crushing, especially in fine crushing and ultra-fine crushing operation. The two cavities meet the crushing requirements of most coarse, medium and fine crushing operations.
Cone crusher is a kind of crusher that can crush ore of about 400 and 500mm into 10-30mm crusher equipment. In gravel aggregate crushing production line and metal ore crushing production line, cone crusher is the core equipment for medium crushing and fine crushing operation.
Cone crushing is suitable for fine crushing and ultra-fine crushing of hard rock, ore, slag, refractory, etc. The laminated crushing principle is used to crush materials. Through the optimization of equipment and cavity, the laminated crushing efficiency is improved. The crushing efficiency is high, the wear of vulnerable parts is low, the particle shape of finished products is cubic, and the content of fine particles is high, so as to improve the quality of finished products and reduce the production cost of equipment and the whole system.
Sand Making Machine
The sand making machine is the key crushing equipment in the sand and aggregate industry, which can crush large stones such as granite, limestone and river pebbles into 0-5mm small particles of sand and stone. At present, due to the restrictions on the exploitation of river sand and lake sand and the severe crackdown on the illegal exploitation of sea sand, the sand making machine is widely used in the field of producing high-quality commercial concrete aggregate, building materials and road and bridge construction.
Mobile crusher is a new type of equipment. It has been optimized and innovated in structural design, equipment configuration and combined application. The combination is more flexible, which greatly widens the application field of tire mobile crushing station and truly realizes the proximity treatment of materials.
Mobile crushers can be further subdivided into tire type mobile crushers and crawler type mobile crushers. Although they have certain differences in specific structure and operation performance, they both have the characteristics of convenience, flexibility, walking and stopping and local operation:
1. Integrated design of the whole machine. The structure is compact, integrating crushing, sand making, screening and transportation, and the carrying equipment is flexible and diverse.
2. Additional power traction and drive. The locomotive traction or diesel power shall be used for walking, and the operation site shall be transferred at any time according to the demand.
3. Wireless remote control operation. Compared with the traditional fixed crusher, one person can operate it remotely, which saves manpower and worry.
Understanding the crushing stage and the type of crusher best suited for each stage can simplify equipment selection. According to our practical application, the most suitable stone crusher is selected for our quarrying operations.