As the name implies, the high-frequency dehydration vibrating screen can reduce the moisture in the material. Generally, it is widely used in the mining sand and gravel industry. The cleaned sand is then sent to the dewatering screen for secondary dehydration, which can reduce the mud content in the sand to the specified level. Degree. At present, it has good applicability for the screening and dehydration of fine sand, and it also plays an indispensable role. But if the high-frequency dewatering vibrating screen is not completely dehydrated, it must be reworked and will increase the screening workload. So what is the reason for the incomplete dewatering of the high-frequency dewatering vibrating screen? The following experienced vibrating screen manufacturers will answer this question for everyone.

Reasons for incomplete dehydration of high-frequency dehydration vibrating screen

1. The reason for the screen

The dewatering screen is not tightened, and the transmission belt is too loose. The above two conditions are likely to cause incomplete dewatering, which is not conducive to the normal progress of the screening operation, and then affects the dewatering quality. In addition, the blockage of the sieve on the screen causes excessive load. More, it will also cause incomplete dehydration.

Solution: The screen should be tightened, and the transmission belt should be tightened; the screen surface should be cleaned in time.

2. The material layer on the screen is too thick

The over-thick material layer on the screen surface may be due to too much feed, or the above-mentioned sieve hole is blocked, which will cause the feed layer to be too thick, and then the dewatering screen will not work, so this is also the reason for the incomplete dewatering One. Greatly reduce the working efficiency of the screen machine.

Solution: Reduce the feed of the dewatering screen.

3. Reasons for material size

The vibrating dewatering screen material with a particle size smaller than 3/4 of the mesh size is easy to steal through the sieve, and is called easy sieve; the particle is larger than 3/4 of the sieve, and it is difficult to pass through the sieve. It is used for the special slurry dehydration of coal water slurry. The effect of the sieve is called particles that are difficult to sizing; particles with a particle size of 1-1.5 times the mesh size are called particles.

Solution: Screening contains a large number of finer materials of finer grades, and auxiliary screening methods can be added. The auxiliary sieve with a larger mesh size is used to pre-screen the grade of the product on the sieve. When used for the screening, dewatering and de-intermediation of finer materials, the equipment length of the screening machine is generally 5.6-7m, and the length ratio is about 3.

4. Uneven feeding of the sieve machine

Uneven feed will not only cause material accumulation and breakage, but too little feed will greatly reduce production efficiency, and too much accumulation will easily cause poor screening quality, and even cause equipment operation failure if it is serious.

Solution: The feeding of the screen machine should be adjusted to ensure uniform feeding.

5. Other reasons

(1) The horizontal level of the dewatering screen box is correct. Solution: adjust the height of the support; change the inclination angle of the screen box to increase the inclination angle;

(2) The steel support spring of the dewatering screen is too large or damaged. Solution: Adjust or replace the dewatering screen spring.

Precautions for the use of high-frequency dehydration vibrating screen

1. Pay attention to the smoothness of the bearing during the operation of the vibration motor of the dewatering screen. Under normal operating conditions, the accumulated operation time is about 1600 hours, the bearing grease should be replaced and the bearing, bearing chamber, and bearing gland should be cleaned.

2. After the dewatering screen is suspended or stored for more than half a year, the motor should be disassembled for maintenance and replaced with lubricating grease.

3. After the accumulated operation time of the dewatering screen exceeds 5000 hours, the motor bearing should be checked. If it is damaged, a new bearing should be replaced.

4. After the dewatering screen has been parked for half a year or for a long period of time, the insulation resistance of the motor stator coil to the ground should be measured before use. When measuring with a 500V megohmmeter, the insulation resistance should be no less than 20 megohms.

The above answers the question of what is the reason for the incomplete dehydration of the high-frequency dehydration vibrating screen. I hope it can be helpful to everyone. If there is a problem of incomplete dehydration during actual use, you can follow the reasons and solutions mentioned above. For inspection, if you really don’t know, you can contact the vibrating screen manufacturer purchased at that time for after-sales service.

The vibrating screen generally has a harsh working environment, such as high temperature and high dust. In order to maintain the normal operation of the vibrating screen under this condition, it puts forward higher requirements on the process parameters of the vibrating screen. The process parameters of the vibrating screen are What? How to choose and calculate these parameters? All we need to understand. Reasonable process parameters can also ensure the normal operation of the vibrating screen, and in some respects also extend the service life of the screen.

Process parameters of vibrating screen

1. The inclination angle of the vibrating screen

The inclination angle of the screen surface refers to the angle between the screen surface of the vibrating screen and the horizontal line. The size of the inclination angle will affect the moving speed of the material on the drying surface. When the inclination angle of the screen surface is too large, the moving speed of the material will also increase. Although it can increase the production volume, it will reduce the screening efficiency. On the contrary, if the inclination angle is too small, the screening efficiency will be increased, but the production capacity will be reduced. Linear screens are generally installed horizontally with a zero inclination angle. Horizontal linear screens are generally only suitable for the screening of materials with a particle size of 40mm or less, or for the dehydration, desliming and removal of coal. If it is used for screening materials with a particle size of 50mm or more, the linear screen should have an angle, and the inclination angle is about 5º~10º.

2. Vibrating screen amplitude and frequency

Vibrating screen amplitude refers to the range and intensity of the box vibration, and frequency refers to the number of vibrations per minute of the screen box. When the amplitude is larger, the frequency of screening is higher, and the movement speed and acceleration of the screen box are also greater. When sieving coarse particles, it is recommended to adopt a larger amplitude and a lower frequency; conversely, when sieving fine particles, a smaller amplitude and a higher frequency should be maintained.

3. The length and width of the vibrating screen

When the other conditions of screening are the same, the productivity mainly depends on the width of the screen surface, and the screening efficiency is mainly determined by the length of the screen surface. But it does not mean that the width of the screen surface is as wide as possible, because when the screen surface is too wide, the feeding will be uneven and the rigidity will be poor. The screen surface is too long and can not increase the efficiency of screening, so the screen surface of the appropriate length and width should be selected. Therefore, the aspect ratio is generally 2:3. For the screening of coarse materials, the screen surface length is 3.5~4m. For the screening of medium and fine-grained materials, the screen surface length is 5~6m; the pre-screened screen surface can be shorter than the final screen surface It should be longer.

4. Throwing angle of vibrating screen

The throw angle of the vibrating screen refers to the angle formed between the direction of the box body and the screen surface when the box is moving, that is, the direction angle that the material on the screen surface is thrown by force. The larger the throwing angle, the slower the material movement speed, which will be adequately screened, which is suitable for difficult-to-screen materials. The smaller the projection angle, the faster the material movement speed, which is suitable for easy-to-screen materials.

Selection and calculation of vibrating screen parameters

1. Throwing index

According to experience, depending on the nature of the material to be processed, the theory and production practice for sieving have proved that the particle size is less than 3/4 of the mesh size, called “easy sieve”; the particle size is larger than the mesh size 3/ 4, called “difficult to sieve granules”; the closer the diameter of the granules is to the sieve size, the more difficult it is to penetrate the sieve. Most use medium-speed throwing index 1.75-3.3.

2. Installation inclination

The installation inclination angle is related to the processing capacity and screening efficiency of the vibrating screen.

(1) Material classification and separation, etc.: Installation angle=0°;

(2) Linear vibrating screen: dewatering: installation angle = 0°, negative if necessary; when the material is above 50 mm, the installation angle = 5~10°; when the material is below 40 mm: installation angle = 0°; For mud, de-intermediation, and dehydration: Installation angle = -5°~0°.

3. Installation vibration direction angle

The value of linear vibrating screen is 30~60°, for linear vibrating screen, generally β=45°. The reason is that it has good adaptability, high movement speed and high productivity.

4. The length and width of the screen surface

Calculate the required area according to the actual production use of the sieve, productivity, and the particle size of the material to be screened. If it is a multi-layer screen, it should be calculated layer by layer, and the calculated peak value should be taken, and it should be rounded according to the standard.

(1) The length of the screen surface: below 3.6mm, the interval of each stage is 0.6m; above 3.6mm, the interval of each stage is 0.9m;

(2) Screen width: below 3.0mm, the interval of each step is 0.3m; above 3.0mm, the interval of each step is 0.6m.

5. Vibration tilt angle

The vibration tilt angle is usually 45°, and the tilt angle can be as high as 60° for some difficult-to-screen materials such as crushed stone, coke, and sinter.

6. The moving speed of the screen surface and the thickness of the material layer

The moving speed of the material along the screen surface is usually 0.12~0.4m/s, not more than 1.2m/s. For a circular vibrating screen, the moving speed of the material along the screen surface is related to the inclination angle of the screen surface. The relationship between the thickness δ of the material layer and the sieve size a is shown on the right: δ≤(3~4)a; the relationship between the thickness and the average particle size d0 of the material on the screen is shown on the right: δ≈(2~2.5)d0.

7. Vibrating screen amplitude and spindle speed

The amplitude is generally between 2~8mm. When the sieve is small or used for dehydration, take the small value. When the sieve hole is larger, choose a larger value. For the spindle speed, it can be calculated as follows:

A is the amplitude (mm); n is the spindle speed (n/min)

The above content summarizes what the process parameters of the vibrating screen are, such as the inclination of the screen surface, the amplitude and frequency, the length and width of the screen surface, etc. The vibrating screen obtains the ideal use effect.

A vibration exciter must be installed on the mine vibrating screen equipment to realize the screening of materials. The vibrating screen exciter is a device used to generate the exciting force, which can make the object to be excited obtain a certain form and magnitude of vibration, thereby vibrating the object. In addition to providing exciting force, the exciter also determines the vibration frequency and amplitude of the vibrating screen. Therefore, the correct installation of the vibration exciter is very important. Below, the editor of Hiside will talk about the installation steps and debugging of the vibrating screen exciter.

Installation steps of vibrating screen exciter

1. Before installing the vibrating screen exciter, first refer to the packing list to check whether the parts are complete and damaged.

2. Refer to the installation drawing for installation. The supporting frame must be installed horizontally on the foundation. The foundation should have sufficient rigidity and strength to support all the dynamic and static loads of the vibrating screen.

3. The screen box trunnion can be used to lift the sieve machine, and the whole sieve cannot be directly hung on the exciter. Lift the exciter to the installation position, and use the bolts to locate at four points symmetrically. Install the exciter anchor bolts, and Preload.

4. When installing the vibration exciter, ensure that there is a 75mm gap between the screen box and non-moving parts such as hoppers and troughs.

5. Remove the spreader before tightening the anchor bolts, tighten the exciter anchor bolts diagonally with a torque wrench, and tighten the anchor bolts to a fixed torque.

6. Install the coupling and the protective cover, keep the eccentric block installed in a natural state, and install the vibration exciter and the coupling protective cover in turn. The installation must be firm and reliable.

7. Fill the exciter with lubricating oil, and the grease and oil level meet the requirements.

8. Clean up the scene. Count tools, materials, accessories, and debris on site. The site should be tidy and clean. Then began the debugging work of the vibrating screen exciter.

Debugging steps of vibrating screen exciter

1. The exciter must be rotated by hand (or other methods) before the test run. The machine can be started only when the rotation is flexible and there is no jamming phenomenon.

2. When debugging, adjust the excitation force, first remove the wind shield. Loosen the counterweight fastening bolts, adjust the eccentric block and counterweight of the exciter at the same phase and angle, or increase or decrease the number of counterweights, tighten the bolts, and reinstall the air hood. Adjust the size of the exciting force to meet the needs of different materials or processing capacity of various vibration equipment.

3. The exciter has no abnormal noise, no leakage, and the bearing temperature rise does not exceed 75 degrees Celsius.

4. The trajectory of the vibrating screen is a straight line, the amplitude difference of the four points is less than 2 mm, and the angle difference of the four points is less than 2 degrees.

Precautions for installation and debugging of vibrating screen exciter

1. When hoisting the vibrating screen exciter, don’t bump it when transferring or installing it.

2. Do not disassemble parts and components at will during installation. When installing, check whether the anchor bolt holes are consistent with the bottom plate bolt holes.

3. After the seat type vibration exciter is installed, it should be horizontal horizontally and symmetrical to the center line of the screen body.

4. Turn on the machine for a short time and check whether the working direction of the exciter meets the requirements (the two shafts of the exciter should rotate in opposite directions).

5. The anchor bolts should use strength bolts and take anti-loosening measures to prevent damage to the exciter.

6. The thin oil lubrication exciter needs to open the cooler to supply oil first, check whether the oil circuit is dredged, whether there is oil leakage, and start the test run when the oil return pipe starts to return oil.

7. Do not disassemble parts at will during installation. After installation, the exciter should be horizontal.

8. The bolts connecting the exciter and the screen box are high-strength bolts, which are not allowed to be replaced by ordinary bolts. The tightness must be checked regularly and once a month. The loosening of any one of the bolts will also cause other bolts to be cut, causing damage to the screen machine.

In summary, the installation procedure of the vibrating screen exciter is to first check whether the parts are complete, then lift the exciter to the installation position, install and pre-tighten the anchor bolts, and tighten the anchor bolts to a fixed specified torque. Add lubricating oil. Because of the exciting force of the vibrator, the vibrating screen can run smoothly without swinging and twisting, and produce low noise.

In the mining industry, the work task of the vibrating screen is still very important. It is necessary to screen the materials on the entire production line, and its processing capacity is large, and the screening effect is good. It is also indispensable screening equipment in many other industries. When we use vibrating screen equipment, of course we hope that the equipment can be used for a long time. This is also inseparable from the service life of the equipment, so how to extend the service life of the vibrating screen? Below, the vibrating screen manufacturer gave us the following specific introduction on how to extend the service life of the vibrating screen.

1. Install the vibrating screen correctly

The correct installation of the vibrating screen will help to extend the service life of the equipment. Before, we also specifically talked about how to install and debug the vibrating screen. One of the more important is the installation of the vibration motor. Heavier eccentric blocks are installed at both ends of the vibrating motor. During operation, we can control the excitation force by adjusting the number of eccentric blocks of the vibrating screen. However, due to the heavier eccentric blocks, such as vertical or inclined installation, The bearing has to bear the weight of the eccentric block in the axial direction, which will greatly affect the service life of the bearing. Therefore, when we do not require it, we generally recommend to choose a vertical vibration motor and try to avoid vertical or inclined installation.

2. Keep the vibrating screen stable

Maintain the stability of the vibrating screen equipment during use. Because the proportion of materials handled by the vibrating screen equipment is relatively large, and the work intensity is relatively high, various failure problems may occur during operation. If a failure problem occurs, it must be consuming the life of the vibrating screen. Therefore, the stability of the equipment must be maintained, which is also conducive to prolonging the service life.

3. Maintain the symmetrical balance of the eccentric block

When adjusting the eccentric blocks on both sides of the vibration motor, pay attention to the symmetry as much as possible, that is, the eccentric blocks at both ends should correspond to each other, or the connecting line of the eccentric blocks at both ends should be parallel to the axis of rotation and cannot be different planes. Otherwise, it is easy to make the vibrating screen unstable during operation, which may cause damage or burnout of the vibrating motor.

4. Dust the vibrating screen

Since the working environment of the vibrating screen is mostly harsh and dusty, if the vibrating screen equipment is operated in an open-air environment or in an environment where the protective cover is not tightly sealed, it is easy to get dust and cause the eccentric block to run by friction, thereby burning the motor. Therefore, in places where the working environment is harsh, firstly, increase the sealing of the protective cover, and secondly, frequently clean the dust inside the protective cover. This can also extend the service life of the vibrating screen.

5. Heat dissipation of the vibration motor

The bearing or main parts of the vibration motor are easily burned or burned when the temperature is too high under operation or abnormal operation. We can often vibrate the surface of the motor by vibrating the dust on the motor surface to make it work in good conditions. When working in a large environment, consider subtracting the heat dissipation ribs on the surface of the case. In addition, the equipment can be shut down to dissipate heat after operation.

6. The vibrating screen feeds uniformly

The vibrating screen is a continuous operation equipment, so the vibrating screen equipment needs continuous feeding. If you use too much during feeding, materials will accumulate on the vibrating screen, which will cause the vibrating screen to loosen and reduce fatigue. Due to the high screening efficiency, the equipment itself also increases the work load and damages the vibrating motor, so it is uniform Ground conveying vibrating screen is very important.

7. The material on the sieve surface is sieved cleanly

When the equipment stops production, the material on the screen surface should be sieved clean. After the production is completed, the screen surface materials should be completely screened before the shutdown is performed. This is because the residual materials in the screen surface and the screen body will corrode the linear screen frame and the screen and affect the service life.

8. Regular maintenance of the vibrating screen

Regular maintenance and maintenance of the vibrating screen is also very conducive to prolonging the service life of the vibrating screen. General maintenance is divided into weekly inspection, monthly inspection and annual inspection. The annual inspection is to overhaul the vibrating screen and disassemble the vibrating screen for cleaning. Maintenance also includes regular maintenance and daily maintenance. Regularly check whether the coarse mesh, fine mesh and spring are fatigued and damaged, and whether various parts of the fuselage are damaged due to vibration, and the parts that need to be lubricated must be lubricated.

9. Choose high-quality vibrating screen

The quality of the vibrating screen directly determines the service life of the screen. Many people buy poor quality vibrating screens at increasingly cheaper prices. This is not conducive to production. It is also possible that some unconscionable manufacturers will install bad parts on other vibrating screen equipment and sell them at a low price. This will not only have a low equipment life, but also affect production and safety. There are great negative effects.

10. Handover work must be in place

The production of some enterprises is assembly line operation, and the screening machine works 24 hours a day. This requires the operator to make a record of the shift during the shift, record the output of the screening machine during use, the problems encountered during use and the solutions Wait. This can provide a good review for the next shift and targeted maintenance and observation.

The above is the answer to how to extend the service life of the vibrating screen. In general, there are correct installation of the vibrating screen, maintaining the stability of the vibrating screen, maintaining the symmetrical balance of the eccentric mass, and removing dust from the vibrating screen. The ten measures introduced can effectively extend the service life of the vibrating screen.

Vibrating screen is an important screening equipment in mining equipment. After the material is screened by the vibrating screen, the specifications are clearer and the quality is higher, so its work efficiency affects the benefit of the entire production line. Therefore, it is also very important to choose a suitable vibrating machine, but some novice users may not know how to choose a vibrating screen. Below, the editor of Hiside will summarize a few selection points to teach you how to choose the right one.

Choose according to material characteristics

Each material that needs to be screened has its own unique properties, so choose a vibrating screen suitable for screening the material according to the different properties of the material. These attributes include: density, shape, temperature, viscosity, particle size, mobility, particle size distribution, corrosiveness, etc. According to your different materials, you need to choose different vibrating screens. If you are not sure about this, you can ask the manufacturer’s technicians to help you.

Choose according to the processing volume

1. When the required processing capacity is small, some light linear vibrating screens are cheaper and meet the demand; when the required processing capacity is large, a steel frame is required to ensure the quality. The steel frame of the mine linear vibrating screen can meet the requirements.

2. According to the size of the vibrating screen and the rated processing capacity, select a vibrating motor or a vibrating exciter of appropriate power.

3. Choose different sieve plate angles according to the nature of the material and the processing capacity requirements.

Choose according to the structure of the screen machine

When selecting a vibrating screen, the screen area and number of layers, the shape, size and area rate of the screen hole, as well as the motion mode of the vibrating screen, the vibration frequency and amplitude and other factors should also be considered when selecting the vibrating screen. The screening efficiency of the vibrating screen is related to the movement form of the screen surface, so the screening efficiency of the fixed screen is low, and the screening efficiency of the moving screen is relatively high. For the moving screen, the vibration of particles on the screen surface close to the vertical screen hole direction has a high vibration frequency and a better screening effect; if the particles slide in the direction of the screen surface, the screening effect is relatively poor.

Choose according to the purpose of screening

According to different screening purposes, different types of vibrating screens need to be selected, such as: materials need to be pre-screened, generally linear vibrating screens; for grading and screening of crushed materials, large-scale vibrating screens, probability screens, etc.; for materials For de-intermediation and dewatering, it is better to choose a dewatering vibrating screen.

According to the production site selection

According to the customer’s production site, choose the right size vibrating screen. Technicians need to measure the site on the spot and need to ensure that the linear vibrating screen can be placed in the production line. The more basic is the length, width, and height of the vibrating screen, and the measured values ​​must be accurate, otherwise the vibrating screen produced cannot be placed on the site. The vibration motor and exciter can be placed in different places (bottom or both sides) according to the actual site conditions. In this regard, we must choose a good manufacturer, because to ensure the power of Zhenyuan, Hiside Heavy Industry has rich experience and a large number of talents in the technical department, so it is worth choosing. The excitation force produced by bad manufacturers may not meet the amplitude requirements, which affects production. In addition to the length, width, and height, different shapes of inlet and outlet must be designed according to the production line, such as round and square.

Oother selection elements

1. Easy to repair. Try to choose a model that is easy to maintain under the same conditions. Mine vibrating screens are basically open-air operations, and the processed materials are all mineral materials. The harsh production environment is likely to cause large and small failures in the screen. The easy-to-repair screen can effectively save maintenance time and cost.

2. Parts. All parts and components of the selected models should be standardized and serialized. In this way, when replacing damaged parts, it can be directly replaced without modification and debugging.

3. Security. The selected mine vibrating screen model must ensure the safety of production. Safety in production is more important than Mount Tai, and you must not use unqualified models and accessories to save purchase costs or maintenance costs.

The above is an introduction on how to choose a vibrating screen. The vibrating screen is one of the indispensable equipment in the mining production line. The correct choice can help increase productivity. It can be selected according to the characteristics of the material, such as shape, particle size, density, etc.; Selection of processing capacity; selection according to the structure of the screen, such as screen area, number of layers, etc.; selection according to six aspects such as the selection of screening purposes.