General regulations:

1. Operators and maintenance workers of coal centrifuges must undergo relevant training, and be issued with certificates after passing the examinations.

2. All operators must wear labor protection (including work clothes, hats, shoes, gloves, etc.) according to regulations. Female workers must put their hair braids in their hats. It is forbidden to wear scarves, wear high heels and slippers or work barefoot on site.

3. When cleaning the work site, it is strictly forbidden to wash electrical equipment, cables, lighting, signal lines and equipment transmission parts with water, and do not pour the bearing bush with water to cool down.

4. The work site should always be kept tidy and clean, the ground should be “Five No Leaks” (no coal, no water, no dust, and no debris), and the equipment should be “five no leaks” (no coal, no water, no leakage). No oil, no electricity, no air leakage).

5. The pressure protection and torque limit locking device of the compulsory lubrication system must be complete and intact, sensitive and reliable in action, and it is strictly forbidden to throw it away.

6. The coal centrifuge should be started when there is no load, and it is forbidden to feed in materials or rinse with water before it is started.

7. The coal-carbon centrifuge fails during operation and must be shut down for processing. Before overhauling or opening the observation hole, overhaul hole or locking device, the system must strictly implement the power failure tagging system.

8. The feed of the coal-carbon centrifuge should be kept uniform, and debris, especially iron, should be prohibited from entering the machine. Overload operation is strictly prohibited during operation.

Operating procedures

Coal centrifuge

(1) Check before driving:

1. Check whether the oil level in the fuel tank is appropriate (the appropriate oil level is 3/4~1/2 of the observation window), whether the oil is clean and meets the requirements, whether all cover bolts are fully tightened, and whether there are sundries around that affect the centrifugation The factor of the flexible operation of the machine, there is no debris or loose parts on the screen basket.

2. Turn each rotating wheel by hand to see if the centrifuge can rotate freely (flexibly. Check the tightness and wear of each V-belt, and see if there is any breakage or job-hopping.

3. Check whether the inspection holes and observation windows are tightly closed, and whether the fasteners are firm

4. The start sequence of the centrifuge is: first start the oil pump motor, wait until the oil pressure is normal, then start the main drive motor, and finally start the vibration motor.

(2) Start and stop

Start the car

1. The operation of this equipment is divided into two operation modes: centralized control automatic operation and on-site manual operation. During the normal production period, the centralized control automatic operation mode is adopted, and the on-site manual operation mode can only be adopted in the case of maintenance and failure. The conversion between the two modes is done by centralized control by clicking on the corresponding device icon and then selecting centralized or local completion, or by selecting the operation mode of the entire system from the control homepage as centralized or local completion. Note: The front and rear locking relationship of each device is released when operating in the local manual operation mode. Try to avoid using it in production!

2. Centralized control automatic operation mode: After receiving the command to start the vehicle in the centralized control room, after checking and confirming that there is no maintenance and other personnel work on the associated equipment near the equipment and before and after the equipment, open the lock of the equipment control button and notify the central office. The control room can start the car. The starting process is automatically completed by program control.

3. Check the normal operation of the equipment, vibration and lubrication, and notify the centralized control room for normal coal production.

4. On-site manual operation mode: first contact the centralized control room to confirm whether the equipment is in on-site mode. On the premise of checking and confirming that there is no maintenance and other personnel working on the associated equipment near the equipment and the front and rear of the equipment, open the lock of the equipment control button, and press the start button of the lubricating oil pump to start the oil pump. When the oil pressure exceeds 0 8 bar [delay 30 seconds], press the start button of the main drive motor to start the main motor. After the host is running normally [delay 5 seconds], press the vibration motor start button to start the vibration motor. When the vibration is normal, the start-up process of the whole machine is completed, and the feeding and production can be performed normally.

Stop the car

1. Normal centralized control automatic parking is automatically completed in sequence after the centralized control room clicks the system parking button of the corresponding system.

2. On-site manual normal shutdown method: first stop feeding. After all the materials in the equipment in operation are drained and thoroughly rinsed with water, the machine can be shut down. First, press the stop button of the vibration motor and the main drive motor one after another, and then press the stop button of the oil pump after the equipment is completely stationary.

3. In the centralized control mode, the equipment can be parked by pressing any parking button on the spot.

4. When the oil pressure of the pressure switch drops below the specified value (0.3 bar for the TEMA HSG1400 type) due to the loss of lubricating oil, pipe rupture, blockage, etc., the pressure switch will automatically stop the main motor power supply to achieve shutdown.

5. When the coal centrifuge is overloaded due to material overload, debris jam or mechanical failure, the torque limiting device will automatically stop the main motor power supply to achieve shutdown.

2. Matters needing attention during operation:

1. Pay attention to any abnormal sound during operation, check immediately and eliminate the cause before starting the machine, but note that the number of stops within one hour cannot exceed four times.

2. The feeding requirements are uniform. Pay attention to the filtrate discharge system should have sufficient air volume. The blockage of the ventilation pipe will affect the moisture of the product. The product moisture is high and there are coarse particles in the filtrate. The reasons must be checked and dealt with.

3. Pay attention to whether the mechanical operation and vibration are abnormal, the normal amplitude is 4~5mm, pay attention to the oil level of the lubricating oil tank and the oil return of the oil pipe, pay attention to whether the pressure gauge is normal, and the normal outlet oil pressure is 3.0~3.5 bar. Any situation that occurs should be investigated for the cause, and the system can be turned on only after the treatment is normal.

4. Pay attention to the temperature of the lubricating oil, the normal temperature rise is not more than 35C, and the temperature is not more than 80C.

5. The operation of the equipment should be under the centralized control of the whole plant, pay attention to whether the automatic protection device is working, and the reliability of the pressure switch should be checked regularly.

As we all know, there is a big difference between standing objects and falling objects. For most seemingly tiny objects, paying attention to the details of the operation of the double-row ball slewing ring can prolong its service life. The following is a detailed introduction to this problem, let’s take a look. It should be noted that the operating details of the double-row ball slewing ring can extend its service life.

First of all, the outer packaging is very clear: usually the packaging of the factory brand is very clear from the line to the color, and it is not fuzzy at all.

Secondly, open the package and check whether the surface of the double row ball bearing is turbid. Please pay attention when purchasing imported double row ball rotary bearings. Because the domestic anti-rust technology is not very mature, it is easy to leave some oil stains on the hands after anti-rust treatment. The imported double-row slewing bearing can smell the anti-rust agent, but the anti-rust oil is almost invisible.

Then, the seal text is clear: Whether there are trademarks on the double volleyball slewing support, such as text, labels, etc., the fonts are small, but most of the products produced by the factory use steel stamping technology, and no heat treatment is performed before the text. Therefore, although the font is small and deep concave, it is very clear. The fonts of the counterfeit products are not only blurred, but the printing process is rough. The fonts float on the surface, and some are easy to wipe off by hand.
Similarly, the chamfer is uniform: the chamfer of the double-row ball slewing bearing is also the position on the horizontal and vertical interface. Due to the limitation of the production process, the bottom of the fake double-row ball slewing bearing has been unsatisfactory in processing.

The final sound: Hold the inner sleeve of the double-row ball bearing body with your left hand, and move the outer sleeve of the double-row ball bearing body with your right hand to rotate it, and listen for noise. Most counterfeit products are produced under poor production conditions and are entirely manual milling operations. Some impurities in the sand will be mixed during the production process. The double-row ball slewing bearing is hidden in the body, and there are impurities on the rotating ring.

Methods of controlling dust:

There are foreign objects such as dust in the reverse branch, and there will be no periodic vibration, dust ring, dust ring size vibration and noise, sometimes not.

The dustproof sound is as follows: For double-row ball slewing bearings/wheel bearings, the method of cleaning the bearings, holes, shafts and some supporting parts before installation is improved and strictly cleaned; by removing foreign matter in the lubricant, the sealing performance of the bearing can be improved. It is forbidden to use impure materials or materials containing foreign bodies in plastics.

Ways to control scar sound:

If the rolling bearing of the double-row ball slewing ring is cracked, jagged or rusted, there will be periodic noise and vibration like rivets. The period is likely to be fixed, but most of it corresponds to the speed, which will appear in a continuous channel. Scars, sometimes scars appear on the steel ball, sometimes no scars, this noise will change with the change of installation and lubrication conditions.

The slewing bearing can simultaneously withstand large axial loads, radial loads and overturning moments and other comprehensive loads. It has the characteristics of compact structure, easy to guide rotation, easy installation and easy maintenance. It is widely used in engineering, mining, metallurgy, wind power generation, ships, ports, petroleum, chemical industry, light industry, medical equipment, food, vehicles, robots, etc. , Aerospace, radar, and military industries. Due to installation, working environment and inadequate daily maintenance and other conditions, it is easy to cause defects in the raceway surface. Today, the slewing bearing manufacturer will analyze the reasons for the defects in the raceway surface of the slewing bearing for your reference.

1. Analysis of the causes of spalling on the raceway surface

Due to the serious unevenness or plane distortion of the raceway; after heavy load, the local pressure is too large and exceeds the contact strength of the raceway; due to point impact or long-term overload work, fatigue damage is caused; the raceway is rusted, cracks and gradually expanded; Local strong impact causes the hardened layer to fracture; the hardened layer is uneven or too thin; the harder foreign matter remains in the raceway, which causes the local pressure to be too large; the strip structure in the raw material destroys the hardened layer.


2. Analysis of the cause of pitting or pitting in the raceway and roller

There are hard debris such as sand and iron filings in the raceway; long-term operation of the local raceway under high contact strength causes local fatigue. Due to poor seal maintenance, rainwater or cleaning fluid is immersed in the raceway, causing local pitting or pitting in the raceway and roller; insufficient or loose assembly bolt pre-tightening force causes the axial gap to increase, and the roller is relatively The large overturning moment rotates, the contact stress on the edge of the raceway increases sharply and slips, and the large stress that the roller actually bears is prone to pitting corrosion.

3. Analysis of the reason for the regular linear indentation on the raceway surface

The main reason is that the slewing bearing is statically vibrating at a fixed position for a long time. For example, when a truck crane travels in a rugged and uneven terrain for a long time, the axial clearance increases, causing the roller bus bar to impact the raceway, resulting in linear indentations with equal spacing.

For precision measuring equipment, in order to improve the anti-overturning rigidity of the turntable bearing, it needs to have a certain negative clearance, which will inevitably bring a quantitative static friction torque, and at the same time, an appropriate static friction torque is also required, which is conducive to reducing Oscillation of small systems. But if the static friction torque is too large, it will also bring undesirable consequences.

In order to prevent excessive static friction torque from appearing, the appropriate selection of negative clearance is important, but at the same time, it is necessary to ensure that the radial fit between the turntable bearing and the turntable and the base has a proper clearance, and pay attention to the installation and fastening methods to avoid distortion of the raceway.

Canteens are very familiar to us. There are canteens in major universities and middle schools. The dining halls that make us remember are the dining tables and chairs. How much do you know about dining hall dining tables and chairs? What are the sizes of dining tables and chairs in the cafeteria?

The school dining table and chair is a kind of dining utensils, and its materials are relatively extensive, mainly based on the style of connecting the tabletop and the chair. It is often used in major colleges and universities, specifically for students and employees to eat. The size of the school dining table and chair should be designed according to its shape. In fact, in life, the school dining table and chair that we have seen are relatively rich in shape, including one-piece, backrest, etc., including four people , Six-person, eight-person, etc. The specifications are: four persons 1200x1650x750 (mm), six persons 1600x1650x750 (mm), eight persons 2000x1650x750 (mm)


The dining table produced by our company is the mainstream dining table currently used in schools. The appearance is beautiful, the sitting feeling is comfortable, and it is suitable for a wider range of people.

1. The raw materials of the dining table and chairs come from Baosteel and Anshan Iron and Steel high-quality steel, and the quality is effectively guaranteed;

2. The table top is made of stainless steel (with MDF inside), wear-resistant, high-temperature resistant, fire-resistant, beautiful and firm;

3. The table frame is made of high-quality stainless steel square tube, the thickness can be customized to fully meet the needs of customers. The surface of the frame body is treated with degreasing, rust removal and phosphating, special coating electrostatic spraying, high temperature plasticization, and the appearance is flat and beautiful without rust and anti-corrosion. Corrosion, in line with QB/T2383-1998 light industry standard;

4. The gray-white fireproof board tabletop is formed by high-frequency hot pressing once, and the two-side PVC straight edge design is strong and has good bearing capacity;

5. The seat back is made of PP engineering plastic injection molding, with beautiful appearance, comfortable sitting feeling, stable and durable.

Many people say that details determine success or failure, so when dealing with the question of buying restaurant tables and chairs, you must not buy hastily. Before buying, you can contact a reliable manufacturer to discuss this issue. If the price given by the other party can be accepted by you, you can give priority to it. However, the quality of tables and chairs should be the primary consideration in the purchase process.

Auditorium soft chairs and theater soft chairs are public seats shared by many people, and they are usually very dirty. How do you clean them in general?

Wipe dry the cotton auditorium soft chairs and cinema soft chairs with a soft cloth, and then dry them. Auditorium soft chairs are used in school auditoriums, multimedia classrooms, and movie theaters. It is a seat with a backrest and some armrests. Most of the auditorium soft chairs are composed of four parts: seat, back, armrests and standing feet. Under normal circumstances, the standing feet and the handrails are integrated to form a firmly installed handrail frame. The composition structure is generally steel-wood structure or steel-plastic structure.


Cloth maintenance It is forbidden to use wet cloths, hard objects or chemicals such as acids and alkalis to contact the fabrics, so as not to affect the surface quality and service life. If it is stained with beverages or juices, first use a paper towel to absorb the water, then wipe with warm water and neutral detergent, then use a clean soft cloth to dry, and finally dry at low temperature.

General maintenance only needs to use a clean and soft cloth to wipe gently. If you want to clean the dirt produced by long-term use, the most ideal way is: first wipe with a neutral detergent diluted with warm water, and then wrung out with water Wipe off the cleaning liquid with a rag, and finally polish it with a dry cloth. After it is completely dry, wipe it evenly with an appropriate amount of maintenance agent.

The vacuum cleaner is suitable for auditorium chairs and theater chairs made of all materials. The gap between the seat back, armrest and seat surface can be cleaned with a vacuum cleaner. However, when using a vacuum cleaner, do not use a suction brush to prevent damage to the weaving thread on the textile fabric and make the cloth fluffy. It is also necessary to avoid super suction. This may cause the weaving thread to be torn off. Consider using a small The vacuum cleaner to clean.

Here are five reasons why high-end auditorium soft chairs, conference hall chairs, lecture hall chairs, and solid wood auditorium chairs are popular.

The auditorium soft chair is a very common seat in our lives. It is very common in all kinds of meeting rooms and auditoriums. Even many people have placed the auditorium soft chair in their own homes. So, why are the auditorium soft chairs so common and popular? Obviously, the auditorium soft chairs must have its own unique features and functions worthy of being appreciated.


Next, we will introduce why the auditorium soft chairs are so popular among people. Mainly include the following aspects:

First: The auditorium’s soft chairs are very practical. The auditorium soft chairs produced on the market now have a multi-functional function, can sit and lie down, have different use values ​​in different environments, and work and rest are not wrong.

Second: The materials used in the auditorium soft chairs are getting better and better, and they look more and more high-end and elegant.

Third: The shape design of the auditorium soft chair mostly uses solid wood, which looks beautiful and generous, the shape is novel and unique, and the decorative effect is very good.

Fourth: The auditorium soft chair has a unique return structure, which can save floor space and space.

Fifth: The structure of the auditorium soft chair is sturdy, durable, not easy to damage, and there will be no problems under normal conditions.

The quality of school desk and chair sets are related to the health and development of students, so you must pay attention to their materials and dimensions when purchasing. There are many testing standards for school desks and chairs, such as lifting and adjusting mechanisms should have locking devices or limit devices , The parts should be free from damage, and the flap device should be equipped with buffer or damping devices, etc., which can be selected by referring to these testing standards and relevant national standards when purchasing.

school desks and chairs

What are the testing standards for school desks and chairs?

School desks and chairs are used by students, young, active, and in a high-speed period of growth and development, so school facilities and equipment managers need to pay special attention to when choosing desks and chairs for students. Health, hygiene, environmental protection and safety, so what are the safety items for student desks and chairs? What testing standards should students’ desks and chairs meet? The following are some basic items for desk and chair testing, which must be qualified before they can be used:

1. The lifting and adjusting mechanism should be equipped with a locking device or a limit device, which should be flexible, reliable and safe.

2. The gap between the relative moving mechanical device parts and the human body contact part should be ≥25mm.

3. The flipping device should be equipped with a buffer or damping device.


4. All parts and components should be undamaged.

5. The radius of the rounded corners of the seat surface, chair back and armrests that are in contact with the human body should not be less than 2mm.

6. Some parts that may cause injury should not be accessible to students unless special disassembly tools are used.

7. Desks and chairs should not be disassembled at will, unless special disassembly tools are used.

8. Parts that use lubricating oil should be properly covered.

9. The metal parts should have no unsealed pipe fittings, and the cap should not be easy to fall off.

10. The diameter of all uncovered holes should be ≤5mm or ≥25mm.

11. There should be no burrs, blade corners, sharp edges, penetrating nails, and other sharp objects in the parts in contact with the human body and the parts where items are stored.

In summary, the purchaser must carefully check the relevant standards according to the inspection report to avoid buying unqualified and inferior products that affect the use of students.

I don’t know if you have a very suitable desk when you study before. For students, a suitable desk is really a very necessary item, especially for children who are studying. So what is the standard for school desk and chair sets?

Desk height standard

Generally, the size of a single desk is about 60CM*110CM, and the height of the table is 71-75CM. The distance between the table and the bottom of the drawer is generally 12.5CM. If it exceeds this distance, people will be hit once they get up. If the desk is a wall-mounted desk, a light trough of about 10 cm can be installed at a distance of about 45 cm from the countertop, and a closet or bookshelf can be set above the light trough, so that the eyes will not be exposed to light. Stimulation can ensure sufficient light.


Desk height

If you are preparing desks for elementary school students, the height of the desk should preferably be adjustable, so that the desk can be adjusted according to the height of the students, so as to facilitate the healthy development of physical development, and the adjustable height of the desk is the best Control between 53-79CM, the width and depth of the desk top should be controlled between 120CM and 60CM.

In addition, it is best for the desk to be used that even the corners of the desk can be adjusted, because the best angle for writing on the desk is that the desk top can be tilted about 7 degrees, and the tilt angle of the desk when sitting in front of the desk for reading The best is 45 degrees. If the above-mentioned standards can be met, then this desk and chair can be called a standard desk and chair, and its height is also a good height.

School dining tables and chairs also play an important role in the field of use and the scope of use. For example, wear resistance, antistatic performance and chemical resistance, etc. Among them, school dining tables and chairs with wear resistance are one of the products with a wide range of applications. So how do we repair the school dining table and chair wear

School dining tables and chairs have two wear methods: chiseling wear and high stress wear. Chiseling wear requires relatively high impact loads on fast food dining tables and chairs.


It is often used in the fields of ball mill lining, iron forging and lining bricks for vertical kilns. Since the impact force generated is not large, the wear form is mainly chiseling.

Therefore, when selecting materials, the hardness and wear resistance are mainly considered, and the wear resistance is mainly improved, but for high stress wear.

There are relatively high requirements for the hardness of the surface of school dining tables and chairs, to reduce the phenomenon of surface shedding and embrittlement, to resist the pressure caused by abrasives, and to enhance the service life and use effect.

We only understand the wear and tear of school dining tables and chairs. In the actual use process, we can avoid it through some methods to ensure the good use of the product and extend the service life of the product.

The slewing bearing is a large support bearing that can bear a comprehensive load, and can bear large axial and radial loads and tilting moments at the same time. This product is generally equipped with mounting holes, internal or external gears, lubrication holes or sealing devices, and has the characteristics of compact structure, light weight, good structural rigidity, stable operation, high precision, safety and reliability.

As a professional slewing bearing manufacturer, Luoyang Longda Bearing Co., Ltd. develops and manufactures various bearing products with an inner diameter of 100mm or more in accordance with national standards, such as large-size, extra-large-size deep groove ball bearings, angular contact ball bearings, etc., with advanced science and technology. , Single row, double row and four row cylindrical roller bearings, spherical roller bearings, single row, double row and four row tapered roller bearings, self-aligning ball bearings, thrust ball bearings, thrust roller bearings, slewing rings, split Bearing. LDB logo, products are widely used in national ports, machine tools, mining, metallurgy, electric power, medical, heavy machinery, coal machinery, cement machinery, petroleum exploration, defense industry and other fields.