Research on improving the service life of gears and bearings Sun Zhaosen (Xishan Coal Mine Corporation Dongqu Mine Multi-menage) uses the life method.
In the operation of coal mine machinery, gears and bearings play an important role. Once the gears and bearings are not working properly, the whole or the whole equipment will not be able to operate normally. For this reason, the author has intensively studied the gears and bearings of the coal cutter coal cutting section and the gear reducer of the coal mining machine, and looked for the causes of gear and bearing failure, so as to take effective measures to improve the service life of the gears and bearings. This article will look for the following three aspects: First, after the equipment is raised, it will be overhauled to the maintenance factory. How to ensure the installation quality of the gears and bearings. The second is whether there is an unreasonable design for coal mining equipment. The third is to analyze the causes of damage to gears and bearings.
1 How to ensure the quality of maintenance of the fully mechanized mining equipment 1) Question whether the design of the fully mechanized mining equipment is reasonable, and find that many manufacturers have unreasonable design, such as the rear cover of the M G300 shearer rocker planetary reducer The two-plate bearing 42236 is often damaged. Through analysis, it is found that the M G300 AW shearer has a problem with the matching of the working face conveyor. When the shearer takes the knife, the planetary reducer back cover grinds the conveyor to transfer the groove to the coal plate, resulting in The back cover of the planetary reducer is worn, the crack of the rocker arm of the rear cover is cracked, and the bearing is damaged due to lack of oil or uneven force, so that the shearer is lifted and repaired, which affects normal coal mining. In this case, the manufacturer responded positively to the manufacturer. The manufacturer subsequently improved the shearer manufacturing process of the Xishan Coal Mine Corporation Dongqu Mine, and improved the manufacturing process of the rocker box body, and added a protective layer to ensure that the back cover was not subject to wear. For the early-stage shearer, the wear-resistant material is welded under the back cover during the inspection to protect the end cap. After taking the above measures, the damage of the 42236 bearing is better solved.
2) The 2JS and 3JS reducer used in the transfer machine often have a loose frame failure. When researching this problem, it is found that the power transmitted by the coal cutter and the reducer, the input speed of the motor, and the I-axis structure are basically The same, while the M G300 shearer used in Dongqu Mine for many years did not occur bearing distraction. The reducer I axis uses 92322 bearing 1 disk, 66322 bearing 2 disk, and the cutting part I axis uses 2524 bearing 1 disk and 7524 bearing 2 disk respectively. The stress analysis of the static load and dynamic load of 92322 is 332 kN, 268 kN 66322, and the static load and dynamic load are 332 kN, 328 kN, respectively. The static load and dynamic load are 452 kN. 428 kN. From the above comparison, the I-axis bearing capacity of the shearer cutting section is significantly higher than that of the reducer shaft bearing. From the perspective of bearing damage, the loose bearings are all thrust bearings. The bearing size of 66322 bearing is ×240 mm×50 mm. According to this, we choose bearing 7322 with the same size and size. The bearing size of 7322 bearing is mm kN, 378 kN, which is much higher than the bearing bearing of 66322 bearing. The bearing gland can only be used to meet this requirement when retrofitting. According to the above analysis and judgment, 8 sets of gearboxes have been used in the mine. In the past year, the eight reducers of the transformation have not failed in the coal mining operation, and all the coal mining work of a working face has been successfully completed to ensure the normal production of the mine.
1 Author brief introduction: Sun Zhaosen male born in 1968, graduated from Shenyang Industrial College, Gujiao 030200 in 1990. 2 Analysis of gear damage Causes The main forms of gear damage in fully mechanized mining equipment are gear tooth cutting, tooth surface pitting, tooth surface wear, tooth surface molding Type deformation. The tooth tooth cutting is usually due to overload, the design strength of the gear teeth is not enough, and the main reason for the gear teeth of the fully mechanized mining equipment is that the shaft is broken by the gears, or the foreign matter enters the gear box and the gear is broken.
1) Foreign matter entering the gearbox is mainly caused by human factors. In the uplifting and repairing of the teeth, we have repeatedly found broken studs, nuts and other foreign objects in it. Among them, most of the screws are used, and most of them are screws for the fuel filler cap. These screws enter the gearbox because the operator does not pay attention. In view of this situation, two main methods are adopted: one is to add a filter on the fuel to prevent foreign matter from falling in, and the other is to use a fuel pump to filter the oil to prevent foreign matter from entering the gear box.
2) The main cause of gear pitting and tooth surface wear is due to poor lubrication of the tooth surface, causing pitting or wear of the tooth surface. The thickness of the film is usually less than 0.1 mm, and the thickness of the film is usually less than 0.1 mm, and the thickness of the film is usually less than 0.1 mm. A good lubrication state is called a boundary film. Compared with dry friction, the boundary friction has a lower friction coefficient, which can effectively reduce the wear of machine parts, prolong the service life, greatly improve the load carrying capacity, and expand the use range when oily. When the condition is poor, the boundary lubrication state cannot be formed. There are many bonding points of the metal on the friction surface, so the friction coefficient is high, and the friction coefficient is better than the normal oil quality by about 3 to 4 times. As a result, the wear is greatly increased, resulting in gear failure.
3) Abrasive wear. Some hard fine particles are trapped in the lubricating oil, which wear the tooth surface, causing abnormal and rapid wear of the tooth surface, which accelerates the failure of the gear.
Therefore, oil quality management must be strengthened, and the oil quality should be checked daily. When the oil quality is black and brown, the oil should be replaced with new oil. When the oil quality is milky white, the oil will be clarified from bottom to top after the sample is stationary. Air is mixed in. After the air is removed, it can still be used. If the oil is clarified from top to bottom, it means that the oil is mixed with water. It cannot be used continuously. It should be used after being slightly transparent. Lubricate the oil as required by the specification when refueling. Excessive oil injection will increase the stirring heat of the rotating parts, resulting in less power consumption and less lubrication, which will accelerate the wear of parts and cause some mechanisms to fail. For this reason, the parts of the shearer reducer that need to be refueled are equipped with oil level indicating devices and oiling holes to observe the oil level change. The cooling water of the shearer reducer must be kept clear to ensure that the lubrication is not good due to the high oil temperature. The oil quality used in the fully mechanized mining equipment should be tested regularly to check the oil quality and facilitate the timely replacement of the oil.
4) The tooth surface of the gear is deformed. Mainly occurs in the belt conveyor linkage gear, there are two reasons: First, the gear bearing load is large, when the belt running slope is large, the tooth surface is often severely shaped. Second, the hardness of the tooth surface is low. For this purpose, the accessory supplier is required to provide a gear with a higher hardness. When the belt load is large, the material should be selected to manufacture the gear to ensure the normal operation of the gear.
3 Analysis of bearing damage The failure modes of bearing in fully mechanized mining equipment mainly include bearing lock and bearing wear. The main reason for bearing wear is basically the same as the main reason for gear wear. The analysis is no longer carried out here. The reason for bearing lock is lack of oil. There are two main types of oil shortage: First, the quality of the sealed original used is not enough. Leakage makes the bearing lack of oil. Second, the lubrication system design is not reasonable. For example, the MG 300 AW shearer adopts the splash lubrication method. When the shearer adopts the knife type, it is extremely easy to cause poor lubrication, which makes the rocker's planetary reducer lack of oil. Bearing lock and gear damage accidents. Such accidents occurred in Dongqu Mine, and the high-type rocker arm of MG 300 series shearer used forced lubrication. The oil pump was used to supply oil to the planetary reducer, which solved this problem better. 2JS, 3JS reducer one-axis bearing lubrication and other bearing lubrication are respectively large and small in the two oil pools, separated by a skeleton oil seal. If there is a problem with the skeleton oil seal, it is difficult to find the small oil pool oil entering the large oil pool. Therefore, each shift should check the oil quantity of the two oil pools. The two fuel tanks have a string of oil phenomenon, which causes the planetary reducer to lack oil to damage the bearings and gears.
In summary, to improve the service life of gears and bearings, we should start from the following five aspects. First, when repairing and assembling, strictly follow the maintenance process and maintenance standards to ensure that the assembly of bearings and gears is intact.
Second, for the places where problems often occur during equipment operation, analyze the causes, find the problems, and improve the unreasonable places to better meet the equipment needs. Third, it is necessary to strengthen the daily management of oil quality, especially the electromechanical department should strengthen the oil quality inspection of the fully mechanized mining equipment and improve the scientific basis for replacing the oil in the underground team. Fourth, it is necessary to strengthen personnel management and reduce accidents caused by improper human operations. Fifth, we must use good quality bearings, gears and seals to avoid the inherent defects of the original.
In the operation of coal mine machinery, gears and bearings play an important role. Once the gears and bearings are not working properly, the whole or the whole equipment will not be able to operate normally. For this reason, the author has intensively studied the gears and bearings of the coal cutter coal cutting section and the gear reducer of the coal mining machine, and looked for the causes of gear and bearing failure, so as to take effective measures to improve the service life of the gears and bearings. This article will look for the following three aspects: First, after the equipment is raised, it will be overhauled to the maintenance factory. How to ensure the installation quality of the gears and bearings. The second is whether there is an unreasonable design for coal mining equipment. The third is to analyze the causes of damage to gears and bearings.
1 How to ensure the quality of maintenance of the fully mechanized mining equipment 1) Question whether the design of the fully mechanized mining equipment is reasonable, and find that many manufacturers have unreasonable design, such as the rear cover of the M G300 shearer rocker planetary reducer The two-plate bearing 42236 is often damaged. Through analysis, it is found that the M G300 AW shearer has a problem with the matching of the working face conveyor. When the shearer takes the knife, the planetary reducer back cover grinds the conveyor to transfer the groove to the coal plate, resulting in The back cover of the planetary reducer is worn, the crack of the rocker arm of the rear cover is cracked, and the bearing is damaged due to lack of oil or uneven force, so that the shearer is lifted and repaired, which affects normal coal mining. In this case, the manufacturer responded positively to the manufacturer. The manufacturer subsequently improved the shearer manufacturing process of the Xishan Coal Mine Corporation Dongqu Mine, and improved the manufacturing process of the rocker box body, and added a protective layer to ensure that the back cover was not subject to wear. For the early-stage shearer, the wear-resistant material is welded under the back cover during the inspection to protect the end cap. After taking the above measures, the damage of the 42236 bearing is better solved.
2) The 2JS and 3JS reducer used in the transfer machine often have a loose frame failure. When researching this problem, it is found that the power transmitted by the coal cutter and the reducer, the input speed of the motor, and the I-axis structure are basically The same, while the M G300 shearer used in Dongqu Mine for many years did not occur bearing distraction. The reducer I axis uses 92322 bearing 1 disk, 66322 bearing 2 disk, and the cutting part I axis uses 2524 bearing 1 disk and 7524 bearing 2 disk respectively. The stress analysis of the static load and dynamic load of 92322 is 332 kN, 268 kN 66322, and the static load and dynamic load are 332 kN, 328 kN, respectively. The static load and dynamic load are 452 kN. 428 kN. From the above comparison, the I-axis bearing capacity of the shearer cutting section is significantly higher than that of the reducer shaft bearing. From the perspective of bearing damage, the loose bearings are all thrust bearings. The bearing size of 66322 bearing is ×240 mm×50 mm. According to this, we choose bearing 7322 with the same size and size. The bearing size of 7322 bearing is mm kN, 378 kN, which is much higher than the bearing bearing of 66322 bearing. The bearing gland can only be used to meet this requirement when retrofitting. According to the above analysis and judgment, 8 sets of gearboxes have been used in the mine. In the past year, the eight reducers of the transformation have not failed in the coal mining operation, and all the coal mining work of a working face has been successfully completed to ensure the normal production of the mine.
1 Author brief introduction: Sun Zhaosen male born in 1968, graduated from Shenyang Industrial College, Gujiao 030200 in 1990. 2 Analysis of gear damage Causes The main forms of gear damage in fully mechanized mining equipment are gear tooth cutting, tooth surface pitting, tooth surface wear, tooth surface molding Type deformation. The tooth tooth cutting is usually due to overload, the design strength of the gear teeth is not enough, and the main reason for the gear teeth of the fully mechanized mining equipment is that the shaft is broken by the gears, or the foreign matter enters the gear box and the gear is broken.
1) Foreign matter entering the gearbox is mainly caused by human factors. In the uplifting and repairing of the teeth, we have repeatedly found broken studs, nuts and other foreign objects in it. Among them, most of the screws are used, and most of them are screws for the fuel filler cap. These screws enter the gearbox because the operator does not pay attention. In view of this situation, two main methods are adopted: one is to add a filter on the fuel to prevent foreign matter from falling in, and the other is to use a fuel pump to filter the oil to prevent foreign matter from entering the gear box.
2) The main cause of gear pitting and tooth surface wear is due to poor lubrication of the tooth surface, causing pitting or wear of the tooth surface. The thickness of the film is usually less than 0.1 mm, and the thickness of the film is usually less than 0.1 mm, and the thickness of the film is usually less than 0.1 mm. A good lubrication state is called a boundary film. Compared with dry friction, the boundary friction has a lower friction coefficient, which can effectively reduce the wear of machine parts, prolong the service life, greatly improve the load carrying capacity, and expand the use range when oily. When the condition is poor, the boundary lubrication state cannot be formed. There are many bonding points of the metal on the friction surface, so the friction coefficient is high, and the friction coefficient is better than the normal oil quality by about 3 to 4 times. As a result, the wear is greatly increased, resulting in gear failure.
3) Abrasive wear. Some hard fine particles are trapped in the lubricating oil, which wear the tooth surface, causing abnormal and rapid wear of the tooth surface, which accelerates the failure of the gear.
Therefore, oil quality management must be strengthened, and the oil quality should be checked daily. When the oil quality is black and brown, the oil should be replaced with new oil. When the oil quality is milky white, the oil will be clarified from bottom to top after the sample is stationary. Air is mixed in. After the air is removed, it can still be used. If the oil is clarified from top to bottom, it means that the oil is mixed with water. It cannot be used continuously. It should be used after being slightly transparent. Lubricate the oil as required by the specification when refueling. Excessive oil injection will increase the stirring heat of the rotating parts, resulting in less power consumption and less lubrication, which will accelerate the wear of parts and cause some mechanisms to fail. For this reason, the parts of the shearer reducer that need to be refueled are equipped with oil level indicating devices and oiling holes to observe the oil level change. The cooling water of the shearer reducer must be kept clear to ensure that the lubrication is not good due to the high oil temperature. The oil quality used in the fully mechanized mining equipment should be tested regularly to check the oil quality and facilitate the timely replacement of the oil.
4) The tooth surface of the gear is deformed. Mainly occurs in the belt conveyor linkage gear, there are two reasons: First, the gear bearing load is large, when the belt running slope is large, the tooth surface is often severely shaped. Second, the hardness of the tooth surface is low. For this purpose, the accessory supplier is required to provide a gear with a higher hardness. When the belt load is large, the material should be selected to manufacture the gear to ensure the normal operation of the gear.
3 Analysis of bearing damage The failure modes of bearing in fully mechanized mining equipment mainly include bearing lock and bearing wear. The main reason for bearing wear is basically the same as the main reason for gear wear. The analysis is no longer carried out here. The reason for bearing lock is lack of oil. There are two main types of oil shortage: First, the quality of the sealed original used is not enough. Leakage makes the bearing lack of oil. Second, the lubrication system design is not reasonable. For example, the MG 300 AW shearer adopts the splash lubrication method. When the shearer adopts the knife type, it is extremely easy to cause poor lubrication, which makes the rocker's planetary reducer lack of oil. Bearing lock and gear damage accidents. Such accidents occurred in Dongqu Mine, and the high-type rocker arm of MG 300 series shearer used forced lubrication. The oil pump was used to supply oil to the planetary reducer, which solved this problem better. 2JS, 3JS reducer one-axis bearing lubrication and other bearing lubrication are respectively large and small in the two oil pools, separated by a skeleton oil seal. If there is a problem with the skeleton oil seal, it is difficult to find the small oil pool oil entering the large oil pool. Therefore, each shift should check the oil quantity of the two oil pools. The two fuel tanks have a string of oil phenomenon, which causes the planetary reducer to lack oil to damage the bearings and gears.
In summary, to improve the service life of gears and bearings, we should start from the following five aspects. First, when repairing and assembling, strictly follow the maintenance process and maintenance standards to ensure that the assembly of bearings and gears is intact.
Second, for the places where problems often occur during equipment operation, analyze the causes, find the problems, and improve the unreasonable places to better meet the equipment needs. Third, it is necessary to strengthen the daily management of oil quality, especially the electromechanical department should strengthen the oil quality inspection of the fully mechanized mining equipment and improve the scientific basis for replacing the oil in the underground team. Fourth, it is necessary to strengthen personnel management and reduce accidents caused by improper human operations. Fifth, we must use good quality bearings, gears and seals to avoid the inherent defects of the original.
We have a plant over 5000 square meter space to make hydraulic Die Cutting Machine , about Plate Cutting Machine , we have 20 ton to 45 ton series, regarding Swing Arm Cutting Machine we have 20 ton to 25 ton, and the Gantry Cutting Machine we have semi automatic and full automatic, our speciality is automatic feeding Computerized Cutting Machine , this kind of Automatic Cutting Machine can save a lot of labor cost , and even lady worker can control this machine easily !
Die Cutting Machine
Cutting Machine,Automatic Cutting Machine,Plate Cutting Machine,Leather Punching Machine
DGSF SHOE MACHINERY GROUP ,