Jaw crusher

                                                                Jaw crusher

Jaw crusher, also known as jaw crusher, is mainly used for crushing various ores and large materials with medium particle size. It is widely used in mining, smelting, building materials, highway, railway, water conservancy, chemical industry and other industries. The maximum compressive strength of the crushed material is 320MPa. The performance features are large crushing ratio, uniform product particle size, simple structure, reliable performance, simple maintenance and low operation cost.
Basic introduction
This series of jaw crusher (jaw crusher) has the characteristics of large crushing ratio, uniform product particle size, simple structure, reliable operation, simple maintenance and economic operation cost. Jaw crusher is widely used in mining, building materials, chemical industry, metallurgy and other industries. It can perform coarse and medium crushing operation on various ores, rocks and other materials with compressive strength not greater than 320MPa. It is the preferred equipment for crushing ore materials such as ore crusher and coal gangue crusher.
Jaw crusher is mainly used as coarse crusher and medium crusher in mining, building materials, infrastructure and other departments. According to the width of the feed inlet, it is divided into large, medium and small machines. Large machines with a feed inlet width of more than 600mm, medium machines with a feed inlet width of 300-600mm and small machines with a feed inlet width of less than 300mm. The jaw crusher has the advantages of simple structure, easy manufacture, reliable operation and convenient use and maintenance.
The working part of the jaw crusher consists of two jaw plates, one is the fixed jaw plate (fixed jaw), which is vertically (or slightly outward inclined at the upper end) fixed on the front wall of the machine body, and the other is the movable jaw plate (moving jaw), which is inclined in position and forms a crushing cavity (working cavity) with the fixed jaw plate. The movable jaw plate makes periodic reciprocating motion against the fixed jaw plate, sometimes separated and sometimes close. When separating, the material enters the crushing chamber and the finished product is discharged from the lower part; When approaching, the material installed between the two jaw plates is crushed by extrusion, bending and splitting.
Jaw crusher can be divided into simple swing jaw crusher (simple swing jaw crusher) according to different swing modes of movable jaw plate. Complex swing jaw crusher (compound swing jaw crusher) and comprehensive swing jaw crusher.
working principle
Principle of single pendulum jaw crusher
The movable jaw is hung on the spindle and can swing left and right. When the eccentric shaft rotates, the connecting rod reciprocates up and down, driving the two thrust plates to reciprocate, so as to
Push the moving jaw to make left-right reciprocating motion to realize crushing and unloading. This kind of crusher adopts crank double connecting rod mechanism. Although there is a great crushing reaction force on the moving jaw, the eccentric shaft and connecting rod bear little force. Therefore, it is mostly made into large machines and medium-sized machines in industry to crush hard materials. In addition, when the crusher works, the motion track of each point on the moving jaw is an arc centered on the mandrel, the radius of the arc is equal to the distance from the point to the axis, the upper arc is small, the lower arc is large, the crushing efficiency is low, and the crushing ratio is generally 3-6 Because of the simple movement track, it is called simple swing jaw crusher.
Simple pendulum jaw crusher has compact and simple structure, and the force of transmission parts such as eccentric shaft is small; Due to the small vertical displacement of the moving jaw, there are less materials during processing, there is excessive crushing, and the wear of the moving jaw plate is small.
Principle of folding compound pendulum jaw crusher
The upper end of the movable jaw is directly suspended on the eccentric shaft. As the connecting rod of the crank connecting rod mechanism, it is directly driven by the eccentricity of the eccentric shaft. The lower end of the movable jaw is hinged with the thrust plate and supported on the rear wall of the frame. When the trajectory of the lower part of the jaw is an ellipse, the more eccentric the connecting point of the lower part of the circle is, and the more eccentric the axis of the jaw is, the more the connecting point of the lower part of the circle becomes, and the more eccentric the axis of the jaw becomes. Because the movement track of each point on the moving jaw in this machine is relatively complex, it is called complex swing jaw crusher.
Compared with the simple pendulum jaw crusher, the compound pendulum jaw crusher has the advantages of lighter weight, fewer components, more compact structure, better filling degree in the crushing cavity, uniform crushing of the loaded material blocks, and forced unloading of the finished products at the lower end of the moving jaw. Therefore, the productivity is higher, which is 20-30% higher than that of the simple pendulum jaw crusher of the same specification; The material block has a large up and down rolling movement at the lower part of the moving jaw, which is easy to unload in the shape of a cube, reducing the flake components like those in simple pendulum products, and the product quality is better.
Difference between simple swing and complex swing of folding jaw crusher
Jaw crusher (jaw crusher) is divided into two types: simple swing jaw crusher and complex swing jaw crusher. Their working principles are very similar, and the motion trajectories of moving jaw are quite different. For simple swing jaw crusher, because the moving jaw is suspended on the support shaft, when the moving jaw moves back and forth, the motion trajectory of each point on the moving jaw is circular arc, and the horizontal stroke is small up and large down, and the bottom of the moving jaw (at the ore discharge port) is the largest. Since the upper part of the ore falling into the crushing chamber is a large ore block, which often cannot reach the necessary compression amount for ore crushing, the upper large ore needs to be crushed repeatedly before it can be broken. The crushing load is mostly concentrated in the lower part of the crushing chamber, and the whole jaw plate does not work evenly, which reduces the production capacity of the crusher. At the same time, the crusher has small vertical stroke, small grinding and stripping effect and slow ore discharge speed. However, the wear of jaw plate is light and the product is too crushed. For the complex swing jaw crusher, because its moving jaw is also the connecting rod of the crank connecting rod mechanism, driven by the eccentric shaft, the motion track of the upper point of the moving jaw is approximately oval, the ovality is small from top to bottom, and the upper part is approximately circular. The horizontal stroke of this crusher is just opposite to that of the simple pendulum jaw crusher. Its upper part is large and its lower part is small. The horizontal stroke of the upper part is about 1.5 times that of the lower part, which can meet the compression required for the crushing of large ore in the upper part of the crushing chamber. At the same time, the vertical stroke of the whole movable jaw is larger than the horizontal stroke, especially at the ore discharge port. The vertical stroke is about three times that of the horizontal stroke, which is conducive to promoting ore discharge and improving production capacity. The practice shows that under the condition of phase network, the production capacity of compound pendulum jaw crusher is about 30% higher than that of simple pendulum jaw crusher. However, the wear of jaw plate is fast and the product is seriously crushed.
Fold edit the main features of this paragraph
1. The crushing cavity is deep and has no dead zone, which improves the feeding capacity and output.
2. Its crushing ratio is large and the particle size of the product is uniform.
3. The gasket type discharge port adjustment device is reliable, convenient and has a wide adjustment range, which increases the flexibility of the equipment.
4. The lubrication system is safe and reliable, the replacement of parts is convenient, and the maintenance of equipment is simple.
5. The utility model has the advantages of simple structure, reliable operation and low operation cost.
6. Energy saving of equipment: the energy saving of single machine is 15% ~ 30%, and the energy saving of system is more than twice.
7. The adjustment range of discharge port is large, which can meet the requirements of different users.
8. Low noise and less dust.
Collapse and edit the running environment of this section
In the process of crushing huge stones into small stones, the first crusher is usually the "main" crusher. The longest history and strongest crusher is the jaw crusher. When feeding the jaw crusher, the material is poured into the crushing chamber containing jaw teeth from the top inlet. The jaw teeth push the material against the chamber wall with great force to crush it into smaller stones. Supporting the movement of jaw teeth is an eccentric shaft, which runs through the fuselage frame. Eccentric motion is usually generated by flywheels fixed at both ends of the shaft. Spherical roller bearings are often used in flywheel and eccentric support bearings, and the working environment of the bearings is very harsh. The bearing must withstand huge impact load, abrasive sewage and high temperature. Although the working environment is extremely harsh, the jaw crusher still needs to work very reliably, which is the key to ensure production efficiency.
Fold and edit the main components of this section
Fold 1 frame
The frame is a four wall rigid frame with upper and lower openings. It is used to support the eccentric shaft and bear the reaction force of broken materials. It is required to have sufficient strength and stiffness. Generally, it is cast as a whole with cast steel, and high-quality cast iron can also be used to replace cast steel for small machines. The frame of the mainframe needs to be cast in sections, and then firmly connected into a whole with bolts. The casting process is complex. The frame of self-made small jaw crusher can also be welded with thick steel plate, but the stiffness is poor.
Folding 2 Jaw and side guard
Both fixed jaw and movable jaw are composed of jaw bed and jaw plate. The jaw plate is the working part and is fixed on the jaw bed with bolts and wedges. The jaw bed with fixed jaw is the front wall of the frame. The movable jaw bed is hung on the periphery and should have sufficient strength and stiffness to bear the crushing reaction force. Therefore, it is mostly cast steel or cast iron.
Fold 3 driving medium
The eccentric shaft is the main shaft of the crusher, which is made of high carbon steel with huge bending and torsion. The eccentric part shall be finished, heat treated, and the bearing liner shall be cast with Babbitt alloy. One end of the eccentric shaft is equipped with a pulley and the other end with a flywheel.
Fold 4 Regulating device
The adjusting device has wedge type, backing plate type and hydraulic type. Generally, the wedge type is adopted, which is composed of front and rear wedges. The front wedge can move back and forth to resist the rear push plate; The rear wedge is an adjusting wedge, which can move up and down. The inclined planes of the two wedges fit upside down. The screw moves the rear wedge up and down to adjust the size of the discharge port. The outlet adjustment of small jaw crusher is realized by increasing or decreasing the number of gaskets between the rear thrust plate support and the frame.
Fold 5 free wheel
The flywheel is used to make the working stroke of the industrial jaw more uniform, so as to make the jaw of the crusher tend to be empty. The pulley also acts as a flywheel. Flywheels are often made of cast iron or cast steel, and flywheels of small machines are often made into integral ones. Pay attention to static balance during flywheel manufacturing and installation.
Fold 6 Lubrication device
Eccentric shaft bearings usually adopt centralized circulating lubrication. The bearing surfaces of the spindle and thrust plate are generally lubricated with grease through the manual oil gun. The swing angle of the movable jaw is very small, which makes it difficult to lubricate between the spindle and the bearing bush. A number of axial oil grooves are often opened at the bottom of the bearing bush, a ring oil groove is opened in the middle to connect it, and then the oil pump is forced to inject dry butter for lubrication.
Fold and edit the technical parameters of this section
Model and specification Inlet size (mm) Maximum feed particle size (mm) Adjustment range of discharge port (mm) Processing capacity (M / h) Motor (kw) Weight (T)
PE-250 × four hundred two hundred and fifty × four hundred two hundred and ten 20-60 3-13 fifteen two point eight
PE-400 × six hundred four hundred × six hundred three hundred and forty 40-100 10-35 thirty six point five
PE-500 × seven hundred and fifty five hundred × seven hundred and fifty four hundred and twenty-five 50-100 25-60 fifty-five ten point six
PE-600 × nine hundred six hundred × nine hundred five hundred 65-180 30-85 55-75 fifteen point five
PE-750 × one thousand and sixty seven hundred and fifty × one thousand and sixty six hundred and thirty 80-180 72-150 90-110 twenty-eight
PE-800 × one thousand and sixty eight hundred × one thousand and sixty six hundred and eighty 100-200 85-143 90-110 thirty
PE-870 × one thousand and sixty eight hundred and seventy × one thousand and sixty seven hundred and fifty 170-270 145-235 90-110 thirty point five
PE-900 × one thousand and sixty nine hundred × one thousand and sixty seven hundred and eighty 200-290 170-250 90-110 thirty-one
PE-900 × one thousand and two hundred nine hundred × one thousand and two hundred seven hundred and eighty 95-255 100-240 110-132 forty-nine
PE-1000 × one thousand and two hundred one thousand × one thousand and two hundred eight hundred and fifty 195-280 190-275 110-132 fifty-one
PE-1200 × one thousand and five hundred one thousand and two hundred × one thousand and five hundred one thousand and twenty 150-300 250-500 one hundred and sixty one hundred point nine
PEX-150 × seven hundred and fifty one hundred and fifty × seven hundred and fifty one hundred and twenty 18-48 5-16 fifteen three point five
PEX-250 × seven hundred and fifty two hundred and fifty × seven hundred and fifty two hundred and ten 25-60 8-22 twenty-two four point nine
PEX-250 × one thousand two hundred and fifty × one thousand two hundred and ten 25-60 10-32 30-37 six point five
PEX-250 × one thousand and two hundred two hundred and fifty × one thousand and two hundred two hundred and ten 25-60 13-38 thirty-seven seven point seven
PEX-300 × one thousand and three hundred three hundred × one thousand and three hundred two hundred and fifty 20-90 10-65 seventy-five eleven
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Comparison between folding jaw crusher and coarse crushing cone crusher
Compared with jaw crusher, coarse crushing cone crusher has its own advantages and disadvantages.
Advantages of coarse crushing cone crusher: high productivity, less power consumption, stable operation, small vibration, large crushing ratio, uniform product particle size, ore feeding by any party and full feeding. Disadvantages: complex structure, high equipment cost and high machine height. The plant needs to be called high. It is extremely bulky and inconvenient to handle. It is not suitable to break viscous ore, and the operation and maintenance are complex.
Advantages of jaw crusher: simple structure, low manufacturing cost, convenient maintenance, reliable operation, small machine height, easy configuration, and not easy to block the ore with high moisture and viscosity. Disadvantages: low productivity, large power consumption, large vibration, small crushing ratio, uneven product particle size, unable to fill the ore feeding.
[2] When selecting the coarse crushing equipment, a comprehensive analysis and comparison shall be carried out according to different conditions. Generally, large concentrators use coarse crushing cone crushers. Jaw crusher should be selected for medium and small concentrators, especially when dealing with viscous materials. Generally, the choice of crusher can be determined only after calculation and technical and economic comparison.
Fold and edit the instructions of this paragraph
（1） Preparation before starting jaw crusher
1. Carefully check whether the lubrication of the bearing is good and whether there is enough grease at the connection of the elbow plate in the bearing.
2. All fasteners shall be carefully checked for complete tightness.
3. Whether the protective device is in good condition. If unsafe phenomena are found, they shall be eliminated immediately.
4. Check whether there is ore or other sundries in the crushing chamber, and if so, eliminate them immediately.
（2） Starting of jaw crusher
1. The machine and transmission parts can be started only after they are checked and proved to be in normal condition.
2. The machine can only be started under no load.
3. After starting, if abnormal conditions are found, stop the machine immediately, and start it again after finding out the causes and eliminating the hidden dangers.
（3） Maintenance and use of jaw crusher
1. After the crusher operates normally, it can be fed.
2. The materials to be crushed shall be evenly added into the crushing chamber, and the side feeding shall be avoided to prevent sudden load increase or unilateral sudden increase.
3. Under normal working conditions, the temperature rise of the bearing shall not exceed 35 ℃ and the maximum temperature shall not exceed 70 ℃. Otherwise, it shall be stopped immediately to find out the cause and eliminate it.
4. Before shutdown, stop feeding first, and turn off the motor after the crushed materials in the crushing chamber are completely emptied.
（4） Lubrication of jaw crusher
1. Always pay attention to the lubrication of the friction surface in time, which can ensure the normal operation of the machine and prolong the service life.
2. The lubricating grease used in this machine shall be determined according to the place of use, air temperature and other conditions. Generally, calcium base, sodium base or calcium sodium base lubricating grease can be used.
3. The lubricating grease added to the bearing pedestal is 50-70% of its volume, which must be replaced every three months; When changing new oil, clean gasoline or kerosene must be used to clean the dirt in the bearing and bearing seat.
4. The contact between the elbow plate and the elbow pad must be filled with grease before the machine starts.
Repair rules and maintenance of jaw crusher
The maintenance of jaw crusher is very important no matter what kind of machine maintenance.
1. Jaw crusher lubrication
(1) Regular attention and timely lubrication of the friction surface can ensure the normal operation of the machine and prolong its service life.
(2) The lubricating grease used for jaw crusher shall be determined according to the place of use and temperature conditions. Generally, calcium base, sodium base and calcium base lubricating grease shall be used

(3) The lubricating grease added into the bearing pedestal is about 50% of its space volume, and it shall be replaced every 3 ~ 6 months. Clean the raceway of roller bearing with clean gasoline or kerosene during oil change.
(4) Before starting the jaw crusher, an appropriate amount of grease shall be injected between the thrust plate and the thrust plate support.
2. Jaw crusher maintenance
In order to ensure the normal operation of jaw crusher, in addition to correct operation, planned maintenance must be carried out, including daily maintenance and inspection, minor repair, medium repair and overhaul.
(1) Minor repair mainly includes checking and repairing the adjustment device, adjusting the clearance of discharge port, and turning or replacing the worn lining plate. Check the transmission part and lubrication system, and change the lubricating oil in time. The period of minor repair is about 1 ~ 3 months.
(2) Besides minor repair, the intermediate repair department also includes the replacement of thrust plate and lining plate, inspection and repair of bearing bush, etc. The period of intermediate repair is generally about 1 ~ 2 years.
(3) In addition to the intermediate repair at the overhaul, it also includes turning and replacing the eccentric shaft and jaw shaft, casting Babbitt alloy on the upper part of the connecting rod head, and replacing or repairing a worn part. The overhaul cycle is generally about 5 years.
Fault causes and troubleshooting of jaw crusher
fault Cause Exclusion method
1. The flywheel rotates but the movable jaw stops swinging 1. The thrust plate is broken
2. The connecting rod is damaged
3. The spring is broken 1. Replace the thrust plate
2. Repair the connecting rod
3. Replace the spring
2. Loose gear plate and metal impact Gear plate fixing screw or side wedge plate is loose or loose Tighten or replace screws or side wedges
3. The bearing temperature is too high 1. Insufficient or dirty grease
2. Improper bearing clearance or poor bearing contact or bearing damage 1. Add new grease 2 Adjust the tightness of the bearing or trim the bearing seat bush or replace the bearing
4. Coarsening of product particle size The lower part of the toothed plate is significantly worn Turn the toothed plate around or adjust the discharge port
5. The thrust plate bearing pad produces impact sound 1. Insufficient spring tension
2. The bearing pad is worn or loose 1. Adjust the spring force or replace the spring
2. Fasten or correct the support seat
6. The spring is broken The spring is not loosened when adjusting the discharge port When the discharge port is adjusted, first loosen the spring, and properly tighten the pull rod nut after adjustment
7. Machine runout Loose fastening of anchor bolts Tighten or replace the anchor bolts
Precautions for folding and editing this paragraph
(1) After the crusher operates normally, it can be put into production.
(2) The materials to be crushed shall be evenly added into the crusher cavity, and lateral feeding or full feeding shall be avoided to avoid unilateral overload or overload.
(3) During normal operation, the temperature rise of the bearing shall not exceed 30 ℃, and the maximum temperature shall not exceed 70 ℃. When the above temperature is exceeded, stop the machine immediately, find out the cause and eliminate it.
(4) Before shutdown, stop feeding first, and turn off the power supply only after the materials in the crushing chamber are completely discharged.
(5) During crushing, if the machine stops due to the blockage of materials in the crushing chamber, the power supply shall be turned off immediately to stop the operation. The machine can be started only after the materials in the crushing chamber are cleaned.
(6) After one end of the jaw plate is worn, it can be turned for use.
(7) After the crusher is used for a period of time, the tightening bushing shall be loosened to damage the crusher.
Material selection and assembly
Design and material selection
In the design, the crushing plates of moving jaw and fixed jaw should have the tooth peak to the tooth valley. In this way, in addition to extrusion, there is also bending effect on the materials during crushing, so the materials are relatively easy to be broken. In order to enhance the service life of the crushing plate, the crushing plate of the small and medium-sized crusher is designed into a symmetrical shape from top to bottom, which can be used after the lower part is worn; The crushing plates of the large jaw crusher are designed into several symmetrical pieces, so that the crushing plates can be replaced after wear. The material of crushing plate can be white cast iron. White cast iron has high hardness, good wear resistance, easy source and low price; The disadvantages are brittle, easy to break and short service life. In order to improve the service life of the crushing plate, it is better to use manganese steel containing more than 12% manganese. ZGMn13 is commonly used. Manganese steel has good toughness. Although the hardness is not high (about 210 HB), it will be strengthened under pressure due to the characteristics of cold work hardening. Therefore, it will be worn and strengthened continuously in work until it is worn out of use. After casting, the manganese steel crushing plate shall be subject to water toughening treatment. The operation of water toughening treatment is basically the same as that of quenching, that is, the cast manganese steel crushing plate shall be heated to 1000 ~ 1100 ℃ and then cooled rapidly in water. After water toughening treatment, uniform metallographic structure can be obtained and fixed, which avoids the deterioration of performance due to natural phase transformation in use. The disadvantage of manganese steel is that the price is expensive, but considering the service life and cost, ZGMn13 has longer service life and lower cost than white cast iron.
Folding assembly
During assembly, the crushing plate must be firmly attached to the jaw plate, and the two should be leveled. Soft metals (such as lead, zinc, etc.) should be used as gaskets between the crushing plate and the jaw plate, and fastened with bolts. When the crusher works, the crushing plate shall not be loose, otherwise it is easy to break or wear the crushing plate and reduce the service life of the crushing plate. Therefore, the crushing plate must be installed during assembly, so as to prolong the service life of the crushing plate.
Improvement in the use process to strengthen the service life of the crushing plate. In the production process, the crushing plate acts directly with the materials, and the crushing force is very large. Especially when crushing the materials with high hardness, it will lead to the vibration of the bolts for installing the crushing plate and the loosening of the nuts, which will aggravate the wear of the crushing plate and produce great noise. In serious cases, the falling off or breaking of the crushing plate will shut down the equipment and affect the normal production. In this case, only tightening the bolts and nuts before starting the machine can not completely solve the problem. We should analyze the specific problems according to the actual situation on site, and find ways to take practical and feasible methods to solve the problem. For example, the spring anti loosening and damping device can be used to solve the looseness of the broken plate in the work, so as to prolong the service life of the broken plate and improve the work efficiency. The specific method is to use the spring to make the bolt anti loosening and self tightening device. The device is composed of inner spring gland, spring and outer spring gland. Put the device on the bolt and tighten the nut. Because the spring is compressed by the nut to a certain extent, it has a strong anti vibration effect, and the bolt loosening force generated by the huge crushing force is automatically compensated by the spring tension, so the bolt will not loosen, so as to prolong the service life of the crushing plate, Improve production efficiency. In short, in the process of use, we can find ways to solve specific problems according to the specific situation, so as to prevent the loosening, aggravation of wear and fracture of the broken plate, so as to prolong the service life of the broken plate, reduce the cost and improve the work efficiency.
Conclusion:
Strengthening the service life of jaw crusher can well strengthen the service life of jaw crusher from the aspects of design, material selection, assembly and improvement in the use process, so as to improve the production efficiency of jaw crusher and reduce the production cost.