Solution to the collapse problem of the air duct caused by raw material vertical grinding

Product introduction:https://www.lvssn.com/mill/Raw-material-vertical-mill.html

The raw material grinding mill of 7200t/d production line of a certain company adopts two vertical mills, model jlm7-46.4, and the output is 320t/h when designing the mill, and the output is increased to 360t/h when optimizing the process parameters.Due to the small inclination of the vertical mill outlet pipe, the design Angle is 30°. During normal operation, the outlet pipe frequently accumulates materials, and after enrichment to a certain degree, the collapse occurs. In serious cases, the vertical mill directly stops vibrating, which has a great impact on the equipment.Moreover, starting up after shutdown will increase the power consumption of grinding machine, which has a great influence on the production quality.In order to ensure the normal operation of the equipment, the solution of the collapse problem of the raw material vertical mill air pipe is determined to improve the reliability of the equipment.

 

1. Windpipe collapse reconstruction plan of fresh material vertical grinding

In the raw material A vertical mill and B vertical mill air outlet pipe, add an air charging box, remove the bottom equipment of the 2 vertical mill air outlet pipe and add 4 sets of ceramic air charging box with A width of 480mm (2 sets for each grinding system), wear resistant bolts and flanges, and add A chiller fan of 6110Pa, 2840r/min, 5.5kw and 1257m cubed /h for each of the 2 vertical mill air outlet pipe.
 

Specific plan:

 

Two rows of 9.5m long open chute shall be installed in the pipe, with the width of each row of chute 480mm, the spacing of the two rows of chute 180mm, and the chute 300mm away from the bottom pipe.To avoid the chute wear faster, add a perforated plate at the top of the chute to reduce the impact of materials and wind on the canvas.The installation position of the fan is the cement platform below the cyclone cylinder of the vertical grinding wind pipe, and the diameter of the wind pipe is 150mm.

Through the final transformation, the problem of vibration shutdown of the mill caused by collapse of the export pipeline is completely solved, the reliability of the equipment operation is improved, the labor intensity of the post is reduced, the cost of shutdown caused by collapse is reduced, and the cost is saved.
 

2. Process operation control after modification

 

Due to the high storage position of homogenized raw materials, a mill is arranged to run under normal conditions to avoid peak during the day. After shutdown, the hot air baffle into the vertical mill is generally closed to avoid air leakage in the system.Due to the large feeding amount of the kiln system, it is easy to accumulate materials in the pipeline after the hot air baffle is closed. In the process of opening grinding, the accumulated materials are easy to collapse from the hot air baffle and enter the human slag discharge pit through the raw material mill.

Before starting grinding, start the vertical mill slag discharge system and force the circulation fan to draw air. At first, the speed of the concentrator should be set at a low 15Hz. Gradually open the hot air baffle at a rate of 3% each time and at an interval of 1min(gradually open to 99%, the process should be slow).Avoid the occurrence of caving when the hot air baffle is closed.

To reform the mill, the wind pipe inner and process control slurry vertical mill by vibration fault eliminate stopped, collapse of the effect of reduced due to the collapse of material on the equipment, reducing the key the increased cost of electricity, reduce the labor intensity of the jobs, let the enterprise realize the authors from the real efficiency, guarantee the safe and stable operation of the system.

The page source:https://www.lvssn.com/Industry/Solution-to-the-collapse-problem-of-the-air-duct-caused-by-raw-material-vertical-grinding.html

The service life solution of rolling mortar wall of cone crusher

Product introduction:https://www.lvssn.com/crusher/Cone-crusher.html

In the cone crusher, the crushing cavity is formed by the cavity between two lining plates: namely, the cavity between the rolling mortar wall (fixed cone lining plate) and the crushing wall (moving cone lining plate).It can be seen that the broken wall and the rolling mortar wall are the parts directly in contact with the materials, and they are also the main wear-resistant parts in the cone crusher.So, cone crusher rolling mortar wall broken wall service life solution, cone crusher broken wall and rolling mortar wall can be used for how long?What are the factors that affect its service life?How to replace after wear and tear?
 

1. How long can the broken wall and mortar wall last?

 

The rolling mortar wall and the broken wall are the main parts which work together in the broken cone.During the operation of the cone breaking, the broken wall will make track movement, and the distance between the broken wall and the rolling mortar wall will be close to and away from, until the crushed material is extruded, and part of the material will be discharged from the edge discharge port.In the cone crusher, the broken wall and the rolled mortar wall are the main parts in direct contact with the materials, and the service life is about 6 months.
 

2. Factors affecting the service life of broken wall and rolling mortar wall

Generally, these factors affect the crushing effect and service life of the broken wall and rolling mortar wall: the content of stone powder and water content, the hardness and particle size of the stone, the way of feeding, the quality of the broken wall and rolling mortar wall itself.

 

2.1 stone powder content and moisture content

When the cone crusher works, if the stone powder content and water content of the material is relatively high, it will lead to easy adhesion to the broken wall and rolling mortar wall during crushing. A long time will not only reduce the production efficiency, but also cause corrosion to the broken wall and rolling mortar wall, reducing its service life.
 

2.2 hardness and particle size of stone

According to the different hardness of the broken material of the cone crusher, the degree of wear on the broken wall and the rolling mortar wall is also different.The higher the hardness of the material, the more difficult it is to break, the greater the impact load the broken wall and rolling mortar wall bear in the production, and the service life will be shortened accordingly.When the hardness of the ore is the same, the larger the particle size of the ore entering the crushing chamber is, the more serious the wear of the lining plate will be, and the service life will be shortened.
 

2.3 feeding method

The feeding mode of the cone crusher also has a certain influence on the service life of the broken wall and the rolling mortar wall.If the feeding device of the cone crusher is not installed properly, or too much material is put into the crushing chamber, it will lead to uneven feeding, material blockage in the crushing chamber and other faults, so that the crushing wall rolling mortar wall unilateral stress is too large, increase the cutting wear of the ore, so that the lining plate is seriously damaged, the service life will be reduced.
 

2.4 quality of broken wall and rolled mortar wall itself

Above is the external factors affecting the crushing wall and rolling mortar wall, crushing wall and the quality of the rolling mortar wall itself are the main factors, a good quality wear-resistant parts, on the surface of casting is requires a high degree of castings are not allowed to have cracks and impact performance of slag inclusion, sand inclusion, cold insulation, blow hole, shrinkage cavity, shrinkage porosity, casting defects such as lack of meat.At present, the market cone crusher crushing wall rolling mortar wall generally made of high manganese steel.With the continuous development of science and technology, the performance of wear-resistant materials is also improving.Overall, choose a material that can harden quickly under impact loading to form a hard and wear-resistant surface while still retaining the original toughness of the inner metal.In this way, the service life of broken wall and rolling mortar wall can be improved.
 

3. How to replace the broken wall and mortar wall?

When replacing the broken wall and rolled mortar wall of the cone crusher, it is necessary to check the wear of the fixed cone, adjusting ring, locking thread, counterweight and counterweight protection plate.If wear and tear should be replaced with a new, and then install the liner, which can reduce the second replacement disassembly time, save time and effort.After installation, please check whether the center of the lining plate is aligned, otherwise, the lining plate will cause serious wear in collision during operation.

 

3.1 replacement of rolling mortar wall

Rolling mortar wall can be replaced on site.Unscrew the installed on the computer on the shelf adjustment screw (note that spin counterclockwise), remove the chamber on the hopper assembly, hoist with lifting equipment adjustment screw, remove the adjustment screw plate bolt, can remove the rolling mortar wall and exchange, should wash the surface when assembling, adjusting screw thread surface besmear butter, fitted with fixed in accordance with the order.

Note: there are u-shaped screws on the rolling mortar wall, and zinc alloy is injected between them to make them closely combine. When the rolling mortar wall is newly installed or replaced, its tightening condition should be checked after 6-8 hours of work, and the u-shaped screws should be tightened again.
 

3.2 replacement of broken wall

Broken walls can be replaced on site.Hoisted out spindle assembly, in strong support platform, careful not to damage the cone and sphere, and all the oil hole cloth block in order to avoid dust impurities, in turn, remove the distribution plate, lock nut and lock washer, fusible washers, at the site of the old plate 180 ° apart two lug on the welding, it can be broken wall hanging out, also can install the new wall on which the parts are separated by 180 ° is just as two lug on the welding, and then according to the installation, and remove the reverse order finally finished cut two lug.

Note: the cone crushing wall is fixed on the cone body with the cone head, and zinc alloy is cast between the two sides. After the newly installed or replaced cone crushing wall works for 6-8 hours, check its tightening condition, and tighten it immediately if found loose.

The broken wall and rolled mortar wall are important parts of the cone crusher. During the operation of the cone crusher, it should be noted that the materials put into the equipment must meet the crushing requirements. Excessive hardness, excessive moisture or other non-broken materials are strictly forbidden to enter the crushing chamber, otherwise, the broken wall rolling mortar wall will fall off and the equipment will stop.At the same time, cone crusher feeding must be uniform, ore must be in the middle of the distribution plate, material can not directly with the broken wall and rolling mortar wall direct action, to prevent wear uneven.

The page source:https://www.lvssn.com/Product/The-service-life-solution-of-rolling-mortar-wall-of-cone-crusher.html

Optimized efficiency of kaolin rotary kiln

Product introduction:https://www.cementepc.net/burning/Kaolin-dryer.html

In order to optimize the process of kaolin rotary kiln, it is important not only to consider the process flow, but also to choose a reliable manufacturer. There are strict requirements on the reasonable spacing and inspection space of kaolin rotary kiln. The optimized efficiency effect of kaolin rotary kiln mainly includes the following points:

1. Working principle of kaolin rotary kiln

(1) the kaolin rotary kiln operates at high temperature under heavy load alternating and slow speed. The maintenance of the attached equipment and the level of thermal system control are related to the safety and efficiency of the rotary kiln operation.

(2) the maintenance of transmission device focuses on lubrication, running state, dynamic detection and meshing accuracy of gears;

(3) the installation accuracy of the supporting device determines the safe and reliable operation of the rotary kiln. During operation, reasonable control should be paid to the distribution of bearing capacity of each supporting wheel, the arrangement of supporting wheel, the upper and lower pressure and time of the hydraulic retaining wheel, the stress of supporting wheel, and the gap between the belt and the backing plate.

(4) the quality of the sealing device directly affects the thermal system and operating cost of the rotary kiln.It is beneficial to the management of the equipment to strengthen the collation and analysis of the daily maintenance data of the kaolin rotary kiln.
 

2. Optimization of kaolin rotary kiln

(1) in addition to the final supporting transportation equipment, the cylinder, hot air pipe and standard parts of the kaolin rotary kiln can be shortened, which can significantly reduce equipment investment and installation infrastructure costs, reduce pipelines and reduce system resistance.

(2) some people worry that the air pipe at the end of the kiln of kaolin rotary kiln is inclined, and the horizontal movement is very dangerous, and the flue gas at the end of the kiln of kaolin rotary kiln is too high, causing great damage. However, the application example of kaolin rotary kiln shows that the preheater at the end of the kiln is inclined, so long as the body remains unchanged, the use situation is still good.

(3) due to the special relationship between the length of the kaolin rotary kiln and the diameter of the cylinder, the length and width of the factory area can be shortened moderately, and the input of cables and upper and lower pipelines can be further reduced.

The page source:https://www.cementepc.net/company/Optimized-efficiency-of-kaolin-rotary-kiln.html

Jaw crusher bearing damage caused by ＂stuffy car＂ solution

Product introduction:https://www.lvssn.com/crusher/Jaw-crusher.html

There are 4 sets of bearings on the jaw crusher, two sets of bearings are connected between the eccentric shaft and the moving jaw, and two sets of bearings are connected between the eccentric shaft and the frame.At present, most of the bearings of jaw crusher adopt rolling bearing, which has high transmission efficiency and convenient maintenance.But when the bearing burns out, it will cause the jaw crusher to stop suddenly, there is a "boring car" situation.Jaw crusher bearing damage caused by "stuffy car" solution
 

1. Bearing selection of jaw crusher

 

In the use of jaw crusher, bearing to adapt to high speed and high strength working pressure, so in the bearing selection should pay more attention.The selection of rolling bearing should not only meet the requirements of external load, but also give full play to the bearing's own load capacity.The radial load is larger than the axial load, the fulcrum span is larger, the deformation of the shaft is larger, etc.

In the selection of accuracy, first of all, the tolerance of the inner and outer ring of the bearing is ±0.05mm.To reduce the bearing damage of jaw crusher, the bearing accuracy can be changed from ordinary level to C3 level, with higher accuracy.

The clearance of rolling bearing is divided into radial clearance and axial clearance, which respectively represent the movement of another ring from one limit position to another limit position along radial and axial direction when one ring is fixed.Experimental analysis shows that the working clearance value that maximizes the bearing life is a negative value slightly less than zero.Considering the changes caused by the temperature difference between inner and outer rings and the load factors, the best dimensional tolerance and radial clearance tolerance can be selected for the bearing.In the assembly process, the bearing is selected and matched according to the machining tolerance of the inner hole of the jaw and the eccentric shaft of the jaw crushing motor, so that the tolerance fit is in an optimal state.
 

2. Bearing assembly and use method

 

(1) because the bearing needs to use the principle of thermal expansion and cold contraction to achieve interference fit in the assembly process, the heating process must be strictly controlled and appropriate temperature should be selected for heating of bearings of different specifications and sizes.

(2) during the assembly process, a special copper hammer is made to strike the bearing. It is required to strike the bearing diagonally at the same time to ensure that the bearing is balanced into the eccentric shaft.In the process of the eccentric shaft entering the jaw type crushing motor jaw, an iron hammer should be used to move the jaw, and the eccentric shaft should be loaded into the moving jaw by means of interaction without damaging the bearing on the eccentric shaft.

(3) use butter oiler inject grease in the moving jaw, join the jaw crusher bearing grease inside the space for the volume of about 50%, replace a piece every 3 ~ 6 months, oil change when the application of clean gasoline or kerosene cleaning roller bearing raceway, the bearing lubrication full uniform, bearings under heavy load, high temperature to obtain the very good lubrication, prolong the service life of bearing.

(4) before the jaw crusher works, an appropriate amount of grease should be injected between the bracket and the adjustment seat. After idling for a period of time, check whether the working current and voltage are normal and whether the crusher makes abnormal noise before conveying stone for crushing.Buffer measures should be taken at the feed mouth to avoid large stones directly impacting the feed mouth of the crusher. Large stones larger than the size of the feed mouth should be blasted twice before entering the feed mouth to extend the service life of the crusher.

In the jaw crusher, the frame, the moving jaw and the eccentric shaft are the three important parts, and the machining size of each part is closely related. In the machining process, it is required to ensure the tolerance range required by the drawing as much as possible, so as to reduce the accumulated errors in machining and improve the assembly quality.

The page source:https://www.lvssn.com/Product/Jaw-crusher-bearing-damage-caused-by-stuffy-car-solution.html

Working principle and advantages of jaw crusher

Product introduction:https://www.cementepc.net/crusher/Jaw-crusher.html

PE, PEX series jaw crusher for large compound pendulum jaw crusher broken equipment, mainly used in crushing compressive strength less than 350 mpa in all kinds of hard ore and rock, big crushing ratio, high yield, uniform end product size, reliable operation, easy maintenance, low operating costs, this paper mainly introduces the working principle of the jaw crusher and advantage.
 

1. Working principle of jaw crusher

PE, PEX series jaw crusher is powered by an electric motor and drives an eccentric shaft through a belt drive to make the moving jaw move reciprocating according to the predetermined track, thus crushing the materials entering into the crushing chamber composed of fixed jaw plate, movable jaw plate and edge protection plate, and unloading the finished materials through the discharge port at the lower part.The crushing mode of this series of jaw crusher is flexion extrusion type. The motor drives the belt and pulley to make the moving jaw move up and down through the eccentric shaft. When the moving jaw rises, the Angle between the bracket and the moving jaw increases, thus pushing the moving jaw closer to the fixed jaw.When the moving jaw goes down, the Angle between the bracket plate and the moving jaw becomes smaller, the moving jaw plate leaves the fixed jaw plate under the action of the pull rod and spring, and at this time, the broken materials are discharged from the lower mouth of the crushing chamber. With the continuous rotation of the motor, the broken motor jaw is used for periodic crushing and discharging, realizing mass production.
 

2. Performance advantage of jaw crusher

(1) the jaw crusher adopts friction-free crushing mechanism. During the crushing process, the effect of the jaw plate on the material is pure extrusion pressure without relative sliding, so the jaw plate has a long service life.

(2) optimized the structure of the front plate, which deepened the crushing chamber of the jaw crusher and made no dead zone, increased the number of times the material was broken, increased the travel of the moving jaw, made the discharge smooth, and improved the crushing ability;

(3) high production efficiency, large crushing ratio, uniform product size and low energy consumption;

(4) shim type discharge port adjustment device, reliable and convenient, large adjustment range, increase the flexibility of the equipment;

(5) the jaw plate of jaw crusher is made of high strength manganese steel, which is cast in one time, with the characteristics of abrasion resistance, compression resistance and long life.

(6) simple structure, reliable operation, low operating costs, safe and reliable lubrication system, easy replacement of components;

(7) low noise and little dust.

If you need to purchase jaw crusher or cement production line, you can contact our online customer service, we are happy to answer your questions.

The page source:https://www.cementepc.net/productknowledge/Working-principle-and-advantages-of-jaw-crusher.html