The crusher mainly relies on mechanical force in productionDate: 2019-08-06 Views:
At present, the classification and grinding methods used in industrial production mainly rely on mechanical force
The most common are:
(1) extrusion grading
Extrusion grading is to apply pressure on the material when two grading working faces are close to each other so that the grading force increases gradually.Such as the roll crusher, jaw crusher, cone crusher, etc.
(2) splitting classification
Splitting classification refers to the splitting force generated when sharp teeth wedge into the material. The force has a concentrated effect, so that the material is divided into two parts along the splitting surface, and local classification is generated at the action point of splitting force.Such as single, double tooth roller crusher.
(3) breaking or bending grading
To break or bend a material between a grading face as if it were a beam with two (or more) fulcrum under a concentrated load.Apart from the splitting force at the point of operation, it is mainly to make the material be graded by bending force.
(4) the ground
Grinding, it is the grading working face relative sliding on the material, apply shear force to the material, this force is applied to the surface part of the material, so it is suitable for fine material grinding.
(5) impact classification
Impact grading, impact force instantaneous action on the material, material crushing.
The crushing equipment (also called crusher) has the function of separating and crushing coal and selecting stone.It has been widely used in coal preparation plant.The crusher is designed according to the different hardness of coal and gangue and the difference of crushability.When working, the easily broken coal is crushed and leaked to the screen, and the hard grind stone is discharged from the screen.Therefore, when the hardness of coal and gangue is greatly different, the difference of shattering property is significant.The crusher is used to treat the lump coal which has been screened in advance, and is also suitable for raw coal.It can be used for screening, crushing, selecting large gangue, metal debris and wood blocks at the same time.The purpose of one machine is to use the crusher to pick dirt instead of hand.It is of great significance to emancipate workers from heavy manual labor and improve labor efficiency.
The selection of material classification method is mainly based on the particle size of the material, physical and mechanical properties, the required classification ratio and other factors, the selection of classification method should be the most economic, the product after classification is the most in line with the requirements of the next process particle size composition.In the conventional classification method, pure crushing, grinding, impact crushing and other generally not suitable for coal preparation plant classification.Splitting is the cutting edge surface of the crusher wedge into the material, so the material will be graded tensile stress, the tensile stress reached the limit of the material tensile strength, the material will be split and classification, such as the roll crusher classification.
The compressive strength of most rock and mineral materials is much higher than their shear and tensile strength.The reason of low shear and tensile strength is that internal defects (joints and cracks) of rock and mineral materials are prone to stress concentration and fracture under the action of shear force and tensile force.Therefore, the material is either pulled under the mutual vertical stress, slippage under the action of shear force, or classification under the action of both.Therefore, it is more efficient to use shear and tensile forces to classify materials.