The vibrating screen can only be operated in accordance with the correct safety regulations in the process of use to ensure the normal operation of the equipment. Today, the vibrating screen manufacturer will introduce to you what are the safety operation regulations of the high-frequency vibrating screen that we need to abide by!

Precautions for the installation of high-frequency vibrating screen

(1) When the vibration exciter is installed and repaired, it must not be beaten hard or be different, and ensure that the original bearing is used and not interchangeable.

(2) The thickness and quantity of the eccentric block or counterweight plate attached to the eccentric block must be the same, and the radial clearance of the bearing should be C3 grade.

(3) The connection between the universal joint and the vibration exciters on both sides must be concentric, the eccentric blocks on both sides are in the free plumb position, and the universal joint connecting bolts can pass through smoothly; if there is any deviation during installation, check the universal joint Whether the joints at both ends of the section are concentric, do not swing the eccentric block angle for installation.

(4) The vibrating screen should be installed with springs with the same stiffness. The spring stiffness on both sides of the feeding end and the discharging end should be as consistent as possible, and the allowable height difference does not exceed 3mm.

(5) Both sides of the support seat of the rubber spring of the vibrating screen should be in the same horizontal plane, and the error is between 2-4mm to ensure that the materials on the screen surface advance evenly.

(6) When using electric welding to install or disassemble parts, the ground wire must be directly fixed on the workpiece to be welded and as close as possible to the welding point, and the welding current must not pass through any bearings or joints.

(7) In principle, welding should not be carried out on the side plate. According to the current environment, if connecting components are required, the side plate should be drilled and then connected with bolts.

(8) Universal joints must be concentric, and protective devices must be installed to prevent them from breaking and falling out and hurting people.

The use of high-frequency vibrating screen precautions

1. Understand equipment related knowledge

The operator should ensure that the operator understands the scope of use and technical performance parameters of the equipment; has sufficient understanding and mastery of the structure, principle and maintenance knowledge of the equipment; familiar with the process flow and equipment control of the system; keep in mind the high-frequency vibrating screen Safe operating procedures.

2. Check before operation

(1) The area around the equipment should be checked to ensure that no personnel are left behind to avoid personal injury when the machine is turned on.

(2) Check whether the feeding, discharging chute and under-sieve chute are unblocked.

(3) Check whether the sieve plate and bead bolts are loose, and the wear of the sieve plate.

(4) Check whether the V-belt and flexible sheet are in good condition, whether the tightness is appropriate, and whether there is damage. If there is damage, it should be replaced in time.

(5) Check the connection between the universal joint and the connecting bolts of the transition pressure plate, and check whether the rubber spring is damaged.

(6) Follow the sequence of the process system to ensure that the empty screen is started and all safety equipment is in a safe and operable state.

(7) The vibrating screen must be started under no load, and the material can be fed after the amplitude is stable.

3. Observation during operation

(1) Observe the distribution of materials on the screen, and make appropriate adjustments if necessary to ensure uniform distribution of materials on the screen.

(2) Observe whether the vibration frequency and amplitude of the vibrating screen are abnormal and whether the operation is stable.

(3) Check the temperature of the motor, vibration exciter and transmission bearing seat.

(4) Observe whether there are abnormal noises such as collision and knocking during the operation of the vibrating screen. If it is found, it must be stopped in time.

(5) Check the vibration reduction of the rubber spring.

(6) Under normal operating conditions, the bearing temperature should not exceed 45 degrees.

4. Parking precautions

(1) The amplitude of over-resonance of the vibrating screen during startup and shutdown is 5 times of normal, and it should not exceed 8 times.

(2) In any case, as long as an accident occurs, the operation of the equipment should be stopped before contacting the centralized control room and relevant positions.

(3) Under normal circumstances, the sequence of the process system should be followed, and the vibrating screen should be stopped under no load, and must not be stopped with materials.

(4) Pay attention to the large-amplitude swing when parking to ensure the safety of the equipment, and remember to abide by the safety operation rules of the high-frequency vibrating screen.

Precautions for maintenance of high frequency vibrating screen

(1) After replacing the drive belt, it is necessary to recheck whether the outer end faces of the two pulleys are on the same level.

(2) After the overhaul is completed or the electrical components are replaced, the steering must be checked to ensure the safe use and operation of the vibrating screen.

(3) After the overhaul of the equipment is completed, the vibration exciter must be turned by hand, and the main shaft should rotate flexibly without friction and jamming.

(4) Regularly check the connection parts of each bolt, which must be firm and reliable, and all bolts must not have any looseness.

(5) Regularly check the wear and tear of the sieve plate.

(6) Check the side plates and beams of the vibrating screen once a month.

(7) Regularly check the rubber spring, V-belt, flexible connecting piece and universal joint.

(8) Lubricate each lubricating point and replace the lubricating oil according to the equipment requirements.

(9) Overhaul the vibrating screen once a year, remove all the vibrating screens for cleaning and oil change, carry out a single careful inspection of the bearings, and replace them if necessary.

The above is a very detailed introduction to the safety operation rules of high-frequency vibrating screen, mainly about the operation rules of installation, use, maintenance and other aspects. We can make a relevant understanding. At the same time, if you encounter any problems in operation, you can contact us.

The vibrating screen is one of the indispensable equipment in the coal mine production line. The working efficiency of the vibrating screen also affects the production efficiency of the coal mine production line. As an important screening equipment, the screening effect of the vibrating screen will affect the use value of the product. Therefore, it is very important to choose the appropriate vibrating screen equipment. Here are some factors to consider when choosing a vibrating screen:

First, the characteristics of screening materials

When selecting a vibrating screen, the characteristics of the materials to be screened should be considered, including the content of the material under the sieve, the content of the difficult-to-screen particles, the moisture content of the material, the shape and specific gravity of the material, and the content of clay and other characteristics.

Second, the structure of the vibrating screen

When selecting a vibrating screen, factors such as the screen area, the number of layers, the shape, size and area ratio of the screen hole, as well as the movement mode, vibration frequency and amplitude of the vibrating screen should also be considered.

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 the particles on the screen surface is close to the direction of the vertical screen holes, the vibration frequency is high, and the screening effect is better; if the particles slide in the direction of the screen surface, the screening effect is relatively poor.

Third, screening purpose

According to different screening purposes, different types of vibrating screen need to be selected, such as:

If the material needs to be pre-screened, a circular vibrating screen is generally used; large-scale vibrating screen, probability screen, etc. are used for grading and screening of crushed materials; linear vibrating screen is better for de-intermediation and dehydration treatment of materials; if necessary The material is desilted and sand cleaned, and the probability screen is used.

Fourth, mineral processing requirements

When choosing a vibrating screen, it is also necessary to consider the processing capacity of the production line, the screening method, the screening efficiency and the inclination angle of the vibrating screen.

In the actual production of the coal mining industry, it is necessary to select the larger sieve size and effective screening area as much as possible according to the actual situation and meet the requirements of the particle size of the manufactured sand products, and select the appropriate sieve shape and sieve surface opening. High-efficiency non-metal screen surface to improve the screening effect and work efficiency of sand and gravel materials.

When using a vibrating screen, the screen has two important process indicators: one is the processing capacity, which is a quantitative indicator that indicates the screening work. Another is the screening efficiency, which is a quality indicator that indicates the screening work. Among the products on the sieve, the more the number of fine grades that do not pass through the sieve holes, the worse the sieving effect is. In order to quantitatively evaluate the completeness of sieving, the index of sieving efficiency should be used.

Screening efficiency of vibrating screen: It is an indicator of the working quality of the screen, indicating the degree of screening operation and the quality of screening products. It is usually expressed as a percentage by the ratio of the weight of the undersize product obtained during sieving to the weight of the fractions smaller than the sieve size contained in the raw material.

Because it is difficult to weigh the product of the screening operation in actual production. However, it is possible to perform sieving analysis on each product of the screening operation, thereby measuring the percentage of fine fraction weight of the sieve size through which the ore feeding, the under-screen product and the over-screen product pass through the screening operation. How to calculate the screening efficiency of vibrating screen?

The screening efficiency can be calculated by the lower ore screen: E=β(α-θ)/α(β-θ)*100%.

α——The content of the particle size smaller than the sieve size in the raw material;

β——The content of the particle size smaller than the sieve size in the product under the sieve;

θ——The content of particles smaller than the sieve size in the product on the sieve.

Example: a vibrating screen with a sieve hole of 15 mm, after sampling and sieving analysis, it is known that the 15-0 mm particle size accounts for 50% of the sieved materials, and the product on the sieve contains 8% of the particle size, and the sieving efficiency is calculated. how many?

α (content of the raw material smaller than the size of the sieve size) = 50%, θ (the content of the product on the sieve smaller than the size of the sieve size) = 8%

So: E=100(α-θ)/α ore screen (100-θ)*100%=100(50-8)/50(100-8)*100% =91.3%

Because the screening efficiency of vibrating screen is affected by many factors, it depends on what material to be processed, the composition of the material, the purpose of screening and the moisture content and viscosity of the material.

Determination method of sieving efficiency

Take samples every 15-20 minutes in the material flow entering the sieve and the material flow on the sieve. Sampling should be carried out continuously for 2-4 hours. The average sample obtained is sieved in the inspection sieve. The sieve hole of the inspection sieve is consistent with the The mesh size of the sieve used in production is the same. The percentage content α and θ of the grades smaller than the sieve size in the raw material and the product on the sieve are respectively calculated, and the sieving efficiency can be calculated by substituting them into the formula.

If there is no inspection sieve with the same size as the sieve, you can use a set of sieves for sieving analysis, draw the results into a sieve analysis curve, and then calculate the percentage content of this grade from the sieve analysis curve. a and theta.

To sum up, the low efficiency of vibrating screen is affected by many factors. If the screen is worn, or the quality of the screen surface is not high, particles larger than the screen size will enter the product under the screen. If the screening efficiency increases abnormally and sharply, it is possible that the screen is severely worn, or the screen surface quality is not good. High, the sieve size does not meet the quality requirements, resulting in too many particles larger than the sieve size.

Linear vibrating screen is a kind of vibrating screen, which is widely used in many industries. The equipment is simple to use and has good effect, so it is favored by many users. Although the linear vibrating screen is easy to use, it still needs our careful maintenance during use.

Usually, the linear vibrating screens we see are driven by dual vibration motors. When the two vibration motors are synchronized and counter-rotated, the exciting force generated by the eccentric block cancels each other in the direction parallel to the motor axis, and when the vertical vibration The direction of the motor shaft is stacked as a resultant force, so the motion trajectory of the screen machine is a straight line.

The two motor shafts have an inclination angle relative to the screen surface. Under the combined force of the exciting force and the self-gravity of the material, the material is thrown up on the screen surface and moves forward in a straight line, so as to achieve the purpose of screening and grading the material. In the process of use, the equipment needs frequent maintenance. During the maintenance, the following points need our attention.

1. In the early stage of operation, check the bolts at least once a day to prevent loosening.

2. When it is used again after being left for a long time, the insulation resistance should be measured, which should be greater than 0.5 megohm for the measurement of a 500-volt megger.

3. The vibrating screen and the screen carrier are equipped with special damping rubber, so as to achieve the longest service life. The rubber strip should be properly located between the two, and the damaged damping rubber strip should be replaced.

4. When the rotation direction of the motor does not meet the requirements, adjust the phase sequence of the power supply.

5. After accumulative running for 1500 hours, the bearing should be checked, and if there is serious damage, it should be replaced immediately.

6. The lead angle of the tension plate of the linear vibrating screen can be adjusted. To install the screen, the lead angle bolts should be loosened so that the upper and lower screens can be moved and placed properly. The first tensioning screws and bolts tighten the plate and give slight pressure to drive the lead angle. , until the screen to the screen, firmly tighten the screw direction angle.

7. When replacing the weaving net, it should be ensured that the gap between the side plate of the screen box and the screen is equal to the first tightening and flattening, and the tension is maintained evenly with the tensioning plate, and the tension is checked. If the contact is insufficient, tight or uneven, it is a big cause of premature screen damage.

8. When disassembling the vibrating screen, it should be disassembled carefully from the outside to the inside to avoid artificial damage to the parts. In particular, to eliminate the balance wheel, it must be removed. The removed parts must be cleaned one by one, and carefully inspected. If any damage is found, it should be repaired or replaced in time.

The above are some precautions for the daily maintenance of the linear vibrating screen. In the maintenance process, correct methods must be taken to avoid the occurrence of problems.

Nowadays, the coal slime content in the products of the coal industry increases and contains a lot of water, which brings certain difficulties to the dehydration of coal slime. In the past, the investment in the water treatment of coal slime was relatively large, which was not conducive to the control of production costs, but now the high-frequency dewatering vibrating screen is used, which has the characteristics of large processing capacity and simple process system, which can well dewater the coal slime. High-frequency dewatering screen is a kind of vibrating screen with high frequency and high vibration intensity as the main features. It is suitable for wet separation and solid-liquid separation of fine-grained materials. The vibrating screen manufacturer summarized the working principle of the high-frequency dewatering vibrating screen and introduced the high-frequency dewatering vibrating screen in detail.

Working principle of high frequency dewatering vibrating screen

The working principle of the high-frequency dewatering vibrating screen is to use high-frequency vibration to destroy the surface tension of the pulp, and the fine-grained materials will vibrate at a high speed on the screen surface to accelerate the separation of large-density minerals, and increase the contact between the materials smaller than the separation-sized materials and the screen holes. Probability, double vibration motor or flange type vibration exciter, the two motors are driven outside to make self-synchronized rotation in opposite directions, so that the screen body performs periodic reciprocating motion along a straight line, and fine-grained materials can be quickly screened out through the screen holes , in order to achieve the purpose of screening and dehydration.

Because the high frequency screen adopts high frequency, on the one hand, it destroys the tension on the surface of the pulp and the high-speed oscillation of the fine-grained materials on the screen surface, accelerates the separation of the large-density useful minerals, and increases the contact between the materials smaller than the separation size and the sieve holes. probability. Therefore, better separation conditions are created, so that the materials smaller than the separation particle size, especially the particles with large specific gravity, together with the ore pulp, pass through the sieve holes to become the under-sieve product.

Workflow of high frequency dewatering vibrating screen

1. Two vibration motors with the same parameters installed on the excitation beam symmetrically rotate in opposite directions when they are connected to electricity, and each generates an equal centrifugal force, and the components of the two forces in the vertical vibration direction cancel each other out in opposite directions;

2. The component forces in the parallel vibration direction are superimposed on each other to form a linear vibration force, and the linear vibration force continuously acts on the screen body in a reciprocating cycle, so that the screen body vibrates on the buffer spring;

3. At the same time, the buffer spring reduces the dynamic load of the screen body to the support foundation of the screen machine, and the screen body drives the screen surface to vibrate synchronously, and transmits the force to the material on the screen;

4. The impact material is thrown up on the screen surface to advance for dehydration, the material is continuously input from the feeding chute, and dehydrated through the screen surface, the under-screen material is discharged into the under-screen chute, and the over-screen material is discharged into the discharge chute.

Motion characteristics of high frequency dewatering vibrating screen

According to the needs of mechanical structure and process parameters, the vibrator of the high-frequency dewatering vibrating screen is arranged above the center of gravity of the screen box. This arrangement makes the motion trajectory of the screen machine ellipse at the feeding end, round in the middle, and ellipse at the discharging end. , so the motion trajectory of the high-frequency dewatering vibrating screen is ellipse-circle-ellipse.

Because of this unique motion feature, the long axis of the ellipse at the feed end of the high-frequency dewatering vibrating screen forms an acute angle with the angle between the screen and the long axis of the ellipse at the discharge end, and the angle between the long axis of the ellipse at the discharge end and the screen surface forms an obtuse angle. In this way, the moving speed of the material at the feeding end is greater than that at the discharging end, which ensures that the material can be loosened quickly at the feeding end of the screen, and the material layer is thinner, so that the fine-grained material is layered as soon as possible. The sieve, the water mucosa is broken and dehydrated; and the material speed at the discharge end is small, which can prolong the dehydration time of the material on the sieve surface, thereby improving the dehydration effect. This feature of the screen machine strengthens the dehydration effect.

Advantages of high frequency dewatering vibrating screen

1. Simple and compact structure, high rigidity, high strength and balanced force distribution;

2. The service life is long, and the overall service life of the vibrating screen equipment is as high as 5 years;

3. The screen can be made of wear-resistant polyurethane material, with long service life and high screening efficiency;

4. Low working noise, the noise is lower than 75 decibels, and the operation is stable;

5. Light weight, low power consumption, high vibration intensity (9-12mm), and high screening efficiency;

6. The variety is complete, which can fully meet the screening process requirements of different material characteristics and processing capacity;

7. The operation and maintenance of the screen machine is simple, cost-effective, sufficient spare parts, and timely and thoughtful service. Below we will introduce the maintenance of the dewatering vibrating screen.

Maintenance of high frequency dewatering vibrating screen

1. Check whether the bolts of various parts are loose at any time, and whether the screen frame collides with the chute, etc.

2. The excitation current (amplitude) can be adjusted according to the ore properties and material requirements. In order to make the screen machine complete the task under the premise of high efficiency, the excitation current premise experiment can be done.

3. The electromagnetic exciter and the control box should be protected from water to avoid short circuit. Cover the exciter with a rubber sheet to prevent water and ore slurry from falling into it, forming a short circuit and blocking the air gap.

4. When the equipment is in normal operation, the ore feeding concentration of the sieve should be observed frequently, so that the concentration should be controlled at about 40%, so as to improve the classification efficiency.

5. When the slurry stream fed into the screen by the distribution bucket is too far, the position or angle of the screen frame should be adjusted in real time, so as not to affect the classification efficiency.

6. Because the screen has high classification efficiency, good dehydration function and high concentration of the amount on the screen, the slurry in the screen above the screen has poor mobility, so it should be equipped with a water pipe.

To sum up, the working principle of the high-frequency dewatering vibrating screen is to use high-frequency vibration to destroy the surface tension of the pulp, accelerate the separation of large-density minerals, and increase the probability of contact between the materials smaller than the separation size and the screen holes, and the fine-grained materials are sieved through the screen holes. point. When purchasing, we need to find a suitable vibrating screen model, because different models and specifications have different feeding rates, ranging from ten tons per hour to two hundred tons per hour, and we need to choose according to our own production needs.