-
Why should scraper conveyor be overhauled regularly?
The normal operation of scraper conveyor has a great influence on the safety production and production efficiency of coal. Due to the poor working environment of scraper conveyor, it is necessary to carry out regular maintenance for scraper conveyor after long-term work, no matter whether there is any fault of scraper conveyor. The routine maintenance of scraper conveyor has been introduced. Let's take a look at the precautions for regular maintenance of scraper conveyor.
Regular maintenance is based on the working characteristics of scraper conveyor, the specific work arrangement in the coal mine, to carry out periodic maintenance and repair. The regular maintenance of scraper conveyor can be divided into minor repair, medium repair and major repair.
During the half year minor repair, in addition to the items specified in the daily maintenance, the head and tail roller bearings need to be removed and cleaned, and the smooth grease added. Keep all parts of the machine slot clean and smooth, and remove the dirt on all parts of the machine slot. Clean the chain and sprocket of transmission parts, replace the smooth oil of reducer, check and clean the vent cover, and replace and adjust the tightness of scraper chain if necessary.
The intermediate repair is carried out once a year, mainly to check the wear condition of each part and replace new parts. It mainly includes: check the wear condition of the roller sleeve on the scraper chain, replace the roller sleeve with serious wear; check the wear condition of the gear rail, and replace it if necessary; dismantle and wash the reducer, check the wear condition of the reducer, and replace the parts with severe wear; check the wear condition of the drive chain and sprocket, and replace them if necessary; check the wear condition of the motor bearing, and replace it if necessary, and add smooth grease; check Look at the wear condition of the sprocket shaft group and replace if necessary; look at the wear condition of the scraper chain and replace the severely worn chain links. Check the scraper conveyor and check the deformed cover plate.
Overhaul refers to the inspection of the whole scraper conveyor after mining a working face, including: thorough cleaning and oil change of the reducer and hydraulic coupling; inspection of the insulation and current of the motor, and cleaning of the motor bearings; repair, correction and update of the severely damaged parts.
Luoyang vision mining equipment Co., Ltd. was founded in 1996, is a 24-year experience of coal machinery equipment experts. Many products produced by the company, such as scraper conveyor and scraper transfer machine, have obtained the national safety mark certificate of mining products. The quality and safety of products have been recognized, and the use of customers has also been guaranteed. No matter from the technology, technology in the same industry occupy an absolute advantage, business scope throughout the country's major mining areas. We are willing to cooperate wholeheartedly, develop together and create the future with your support. We use quality framework to build a bridge between us. Welcome to consult and order.
-
Analysis of common faults of scraper conveyor and preventive measures
Scraper conveyor is a commonly used transportation equipment in coal mine production, which is widely used in coal face, transportation lane, connecting lane and ground transportation. Whether the scraper conveyor works normally or not plays an important role in the safety production of the whole coal mine.
Common faults and causes of scraper conveyor
(1) The quality of broken scraper chain is poor, that is, the quality of chain material and welding processing is not up to standard; too much coal is loaded or there is a large amount of coal pressing the scraper; the average load and large dynamic load repeatedly act, resulting in chain fatigue damage; the working face is uneven and not straight, scraper scraping is not straight, chute is not straight; the corrosive water under the well makes the chain ring rust, reducing the chain section and strength; the chain is too tight; The chain has long-term friction with the middle groove and sprocket, which reduces the diameter and strength of the chain section.
(2) The floating chain conveyor is uneven, not straight, with grooves; the scraper chain is too tight, squeezing the coal to one side of the chute; the scraper chain runs on the coal; the scraper is missing, bending too much; there is gangue under the scraper chain.
(3) The head of the chain falling off the chain sprocket of the scraper is not right, and the slide or base of the second section of the head is not smooth; the sprocket is worn out of the limit or bites into sundries; the tightness of the two chains is inconsistent, and the scraper is severely skewed; the scraper is too thin or excessively bent.
(4) The reducer of the scraper conveyor with the chain at the bottom of the scraper chain out of the slot is not straight, bulged and concave, and excessively bent; the length of the two chains is different, which makes the scraper skew; the chute is seriously worn; the scraper is excessively bent, which makes the distance between the two chains shorter.
(5) The gearbox is overheated, leaking oil and making abnormal noise. The gear is excessively worn, poorly meshed, improperly repaired and assembled; the bearing is damaged or the shaft is displaced; the oil quantity is too little or too much, the oil quality is not clean, the cooling is not good, and the heat dissipation is not good; the sealing ring is damaged, the joint surface is not tight, and the bolts of each bearing cover are loose; the coupling is improperly installed, the corner screws are loose, and the operation is overloaded; the gear is poorly meshed, The gear is seriously worn or damaged; there are metal sundries in the box.
(6) The sprocket assembly is overheated, the oil leakage seal is damaged, the lubricating oil is not clean; the bearing is damaged; the oil quantity is insufficient; the sealing ring is damaged or the oil seal is damaged; the gland or the pressing plate bolt is loose; the sealing ring is improperly installed and the fitting is not tight; the cylinder plug is loose.
preventive measure
2.1 precautions in use
Correct installation, timely maintenance and reasonable use can ensure the long-term stable and safe operation of scraper conveyor.
（1） When the scraper chain is installed, the connecting bolts shall be rustproof, the adherents shall be cleaned, and the grease shall be applied; the welding joint of the vertical ring of the ring chain shall be away from the middle plate, and the welding joint of the horizontal chain ring shall be toward the central line of the chute without twist; the screw fastening position shall be away from the middle plate; the large arc concave surface of the scraper shall be consistent with the transportation direction of the conveyor; the screw tightening torque shall be 60 ～ 70N? M; the chain shall be used in pairs. During maintenance, tighten the nuts frequently; correct and replace the bent or broken scraper in time. After the scraper chain is initially installed or operated, the elastic elongation of the initial tension pre addition shall be equal to avoid the chain relaxation. If the initial tension is too small, the chain will be slack, resulting in "feed chain"; if the initial tension is too large, increasing the running resistance will affect the service life of the chain.
(2) When the reducer is assembled, the side clearance and axial clearance of the gear can be adjusted with the help of the adjusting plate. After running for 200H with load, the oil in the box must be cleaned and replaced with new lubricating oil, and then replaced once every half a year. During maintenance and use, check the vent plug once a day to ensure smooth flow; check the oil temperature twice a shift and monitor the sound twice a week; remove the adsorbate on the magnetic oil plug once a week; replace the damaged gear in pairs; replace the lubricating oil when the content of foreign matters in the oil exceeds 2%, the metal abrasive exceeds 0.5% or the water content exceeds 2%.
(3) The liquid injection range of the limited torque hydraulic coupling is 40% - 80% of its working chamber volume. When the liquid injection quantity exceeds the upper limit, the motor cannot be started under heavy load. When the load suddenly increases, the motor will stall and get stuck, and the temperature will rise sharply due to overload during operation, the internal pressure will increase, causing leakage and even mechanical damage. When the liquid injection quantity is lower than the lower limit, the starting ability of the electric motor will be weakened, the transmission power and efficiency will be reduced, and the bearing will not be fully lubricated, Early damage due to noise; fusible plugs cannot be replaced by wood plugs.
2.2 preventive measures for common faults
(1) The chain of scraper chain is blocked or dropped to ensure that the scraper, connecting ring and connecting parts are complete and fastened; the scraper is bent and replaced in time; the chain is tensioned properly; the chain is classified according to the use time and wear condition to prevent the condition difference from being too large for use together; large sundries or large pieces of coal are removed in time; when moving the fuselage, do not bend too large, and the bottom plate shall be flat to prevent the chain from being blocked.
(2) The quality of scraper chain is strictly controlled, and the welding ring chain is used; the daily maintenance is strengthened. When changing shifts every day, the deformed and damaged chute must be handled in time; the pulverized coal, tail pulverized coal and other sundries on both sides must be removed; the worn and severely corroded parts such as connecting ring and connecting bolt shall be replaced in time; the working face or roadway at the installation site shall be straight, The mutual deviation angle between the two middle grooves is within 3 °; before the start of the conveyor, it is forbidden to load coal, and it must be loaded after the conveyor operates normally; during the test run, the length of the chain shall be adjusted by the method of tightening the chain to make it slightly arc at the bottom chain of the head, the length of both sides of the scraper chain must be the same, and it is forbidden to twist.
(3) The overload management of scraper conveyor shall be strengthened, and the equipment shall be maintained in strict accordance with the intact standard to prevent the equipment from being buried by coal. Strengthen the professional education of operators, further improve the quality of mechanical and electrical operators, and fully grasp the equipment performance.
(4) Check the bearing lubrication before checking the meshing clearance of the first and second level gears when the engine is hot; if the bevel gear is loosened by the wooden stick, the meshing is not good; if the bevel gear cannot be moved, and the oil cover cannot cover the seam, the thickness of the metal ring shall be reduced.
-
The scraper conveyor should pay attention to these four aspects in operation
1、 Preparation for scraper conveyor installation
(1) The staff participating in the installation and test run shall carefully read the instructions of the machine, the instructions of supporting equipment and other relevant technical data and safety regulations, and be familiar with the structure, working principle, installation procedures and precautions of the machine;
（2） Check whether the form and capacity of scraper conveyor are suitable for working conditions;
(3) Check all parts, accessories, spare parts and special tools of the machine one by one according to the delivery list and technical data of the machine;
(4) According to the technical data of the whole machine, check the appearance quality and geometry of all parts, and repair and remove the rust in case of collision, deformation and rust. Especially for the explosion-proof equipment, it must be inspected by the full-time explosion-proof inspector, and it can only be put into the well after the permit is issued;
(5) Prepare installation tools and lubricating grease;
(6) Designate the work commander and select the installation site.
In order to check the mechanical properties of the scraper conveyor, make the installation and maintenance personnel and operators familiar with the installation, installation, repair and operation technology, Zui is good to carry out the installation and commissioning on the ground, and can only be installed in the well if there is no problem.
2、 Requirements for ground trial assembly of scraper conveyor
(1) The head of the machine must be placed properly, and the stable pad shall not shake;
(2) The laying of the middle chute shall be flat, stable and straight, and the laying direction must be correct, that is, the approach plate of each section must face the machine head;
(3) The seam between the coal baffle and the groove side shall be tight and tight without any gap;
(4) Scraper conveyor with coal shoveling board, between the coal shoveling board and the tank side shall be tight and tight without gap;
(5) The welding joint of the ring chain shall not face the middle plate and shall not be tightened; the number of links in each section between the double chain scraper plates must be equal. The direction of the scraper shall not be wrong. For the bolts connecting the scraper horizontally, the head must face the running direction; for the bolts connecting the scraper vertically, the head must face the middle plate;
(6) The signal device installed along the scraper conveyor shall meet the specified requirements;
(7) After installation, careful inspection and test run shall be carried out, and only after the operation is normal can preparation work before installation be done.
3、 Procedure when installing scraper conveyor on the ground
(1) All personnel involved in the installation shall always abide by the safety operation procedures, strictly prevent the occurrence of equipment and personal accidents, and prepare the installation process documents;
(2) All parts used for installation shall be transported to the installation site and arranged in order according to the predetermined installation location;
(3) First, install and fix the head together, and connect the power supply with the motor as required;
(4) Pass the scraper chain through the chain path under the head frame, and the chains shall not be intertwined or tightened. The lower side of the welding joint of the ring chain;
(5) Install the tail part of the machine in a similar way, and connect the chain with a quick joint to reach a sufficient length;
(6) Pass the chain around the head and tail sprockets respectively and connect them in the upper chain path, and keep it loose;
(7) Install other parts and components completely according to the general drawing of the equipment;
(8) Remove the sundries at the chain track and check whether the connection and fastening of each part are reliable.
4、 Precautions for no-load test run on the ground
(1) Jog the motor and observe whether the rotation direction of the head and tail motor is correct. Turn on the motor after the direction is consistent, and observe whether there is any jamming and abnormal noise;
(2) The tail driven motor shall be ahead of the head driven motor, generally controlled between 0.0035 and 0.013s/m, accumulated as delay time, but the small lead time of Zui shall not be less than 0.5s, and the large lead time of Zui shall not be more than 3S;
(3) Start the scraper conveyor, check whether there is abnormal noise in the motor and reducer, and the temperature shall not rise suddenly;
(4) Check whether the engagement of chain and sprocket is normal and whether there is chain skipping. Whether the scraper chain has run out in the transition or middle section of the machine head. If there is run out, it means that the pre tension of the chain is too large and should be reduced again;
(5) The scraper chain shall be free of jamming in the whole upper and lower chain tracks.
5、 Preparation before the buried scraper conveyor is lowered into the well
(1) All parts shall be intact, otherwise they shall be repaired;
(2) The components that do not need to be disassembled and lowered into the well shall be fastened and reliable;
(3) The components that need to be disassembled and lowered into the well shall be placed and marked according to the class, the small parts that are easy to lose and mix shall be packed according to the class, and the exposed processing and matching components (such as shaft hole, oil hole, etc.) shall be provided with anti-collision, anti blocking, anti dirt and other measures;
(4) According to the surface installation situation, formulate the process flow of downhole installation and downhole installation, and indicate the transportation location of the downhole components in the obvious position.
6、 Precautions for installation and commissioning of scraper conveyor underground
(1) The installation and commissioning of scraper conveyor in the underground can be carried out according to the order of ground installation and commissioning;
(2) It is installed while running down the well to avoid the accumulation of parts in the upper and lower grooves;
(3) Try to lay the scraper conveyor straight to ensure its reliability and service life;
(4) The no-load operation shall be carried out for 1-2 h first, and the operation condition shall meet the requirements;
(5) Carry out multi machine linkage load operation for 4h, and carry out the following checks:
① All parts are fastened without looseness;
② The tightness of the two scraper chains is basically the same;
③ The temperature of motor, reducer, sprocket shaft and other parts shall not exceed the allowable value of 75 ℃;
④ The electrical system works normally;
⑤ Tighten the chain again. When the tightness is fully loaded according to the specified laying length, it is better to loosen two chain links at the lower part of the machine head, otherwise, it is necessary to tighten the chain again. After all parts are debugged normally, they can be put into normal use.
7、 Installation of scraper conveyor in fully mechanized coal face
-
How to debug and install scraper conveyor
1、 Preparation for scraper conveyor installation
(1) The staff participating in the installation and test run shall carefully read the instructions of the machine, the instructions of supporting equipment and other relevant technical data and safety regulations, and be familiar with the structure, working principle, installation procedures and precautions of the machine;
（2） Check whether the form and capacity of scraper conveyor are suitable for working conditions;
(3) Check all parts, accessories, spare parts and special tools of the machine one by one according to the delivery list and technical data of the machine;
(4) According to the technical data of the whole machine, check the appearance quality and geometry of all parts, and repair and remove the rust in case of collision, deformation and rust. Especially for the explosion-proof equipment, it must be inspected by the full-time explosion-proof inspector, and it can only be put into the well after the permit is issued;
(5) Prepare installation tools and lubricating grease;
(6) Designate the work commander and select the installation site.
In order to check the mechanical properties of the scraper conveyor, make the installation and maintenance personnel and operators familiar with the installation, installation, repair and operation technology, Zui is good to carry out the installation and commissioning on the ground, and can only be installed in the well if there is no problem.
2、 Requirements for ground trial assembly of scraper conveyor
(1) The head of the machine must be placed properly, and the stable pad shall not shake;
(2) The laying of the middle chute shall be flat, stable and straight, and the laying direction must be correct, that is, the approach plate of each section must face the machine head;
(3) The seam between the coal baffle and the groove side shall be tight and tight without any gap;
(4) Scraper conveyor with coal shoveling board, between the coal shoveling board and the tank side shall be tight and tight without gap;
(5) The welding joint of the ring chain shall not face the middle plate and shall not be tightened; the number of links in each section between the double chain scraper plates must be equal. The direction of the scraper shall not be wrong. For the bolts connecting the scraper horizontally, the head must face the running direction; for the bolts connecting the scraper vertically, the head must face the middle plate;
(6) The signal device installed along the scraper conveyor shall meet the specified requirements;
(7) After installation, careful inspection and test run shall be carried out, and only after the operation is normal can preparation work before installation be done.
3、 Procedure when installing scraper conveyor on the ground
(1) All personnel involved in the installation shall always abide by the safety operation procedures, strictly prevent the occurrence of equipment and personal accidents, and prepare the installation process documents;
(2) All parts used for installation shall be transported to the installation site and arranged in order according to the predetermined installation location;
(3) First, install and fix the head together, and connect the power supply with the motor as required;
(4) Pass the scraper chain through the chain path under the head frame, and the chains shall not be intertwined or tightened. The lower side of the welding joint of the ring chain;
(5) Install the tail part of the machine in a similar way, and connect the chain with a quick joint to reach a sufficient length;
(6) Pass the chain around the head and tail sprockets respectively and connect them in the upper chain path, and keep it loose;
(7) Install other parts and components completely according to the general drawing of the equipment;
(8) Remove the sundries at the chain track and check whether the connection and fastening of each part are reliable.
4、 Precautions for no-load test run on the ground
(1) Jog the motor and observe whether the rotation direction of the head and tail motor is correct. Turn on the motor after the direction is consistent, and observe whether there is any jamming and abnormal noise;
(2) The tail driven motor shall be ahead of the head driven motor, generally controlled between 0.0035 and 0.013s/m, accumulated as delay time, but the small lead time of Zui shall not be less than 0.5s, and the large lead time of Zui shall not be more than 3S;
(3) Start the scraper conveyor, check whether there is abnormal noise in the motor and reducer, and the temperature shall not rise suddenly;
(4) Check whether the engagement of chain and sprocket is normal and whether there is chain skipping. Whether the scraper chain has run out in the transition or middle section of the machine head. If there is run out, it means that the pre tension of the chain is too large and should be reduced again;
(5) The scraper chain shall be free of jamming in the whole upper and lower chain tracks.
5、 Preparation before the buried scraper conveyor is lowered into the well
(1) All parts shall be intact, otherwise they shall be repaired;
(2) The components that do not need to be disassembled and lowered into the well shall be fastened and reliable;
(3) The components that need to be disassembled and lowered into the well shall be placed and marked according to the class, the small parts that are easy to lose and mix shall be packed according to the class, and the exposed processing and matching components (such as shaft hole, oil hole, etc.) shall be provided with anti-collision, anti blocking, anti dirt and other measures;
(4) According to the surface installation situation, formulate the process flow of downhole installation and downhole installation, and indicate the transportation location of the downhole components in the obvious position.
6、 Precautions for installation and commissioning of scraper conveyor underground
(1) The installation and commissioning of scraper conveyor in the underground can be carried out according to the order of ground installation and commissioning;
(2) It is installed while running down the well to avoid the accumulation of parts in the upper and lower grooves;
(3) Try to lay the scraper conveyor straight to ensure its reliability and service life;
(4) The no-load operation shall be carried out for 1-2 h first, and the operation condition shall meet the requirements;
(5) Carry out multi machine linkage load operation for 4h, and carry out the following checks:
① All parts are fastened without looseness;
② The tightness of the two scraper chains is basically the same;
③ The temperature of motor, reducer, sprocket shaft and other parts shall not exceed the allowable value of 75 ℃;
④ The electrical system works normally;
⑤ Tighten the chain again. When the tightness is fully loaded according to the specified laying length, it is better to loosen two chain links at the lower part of the machine head, otherwise, it is necessary to tighten the chain again. After all parts are debugged normally, they can be put into normal use.
7、 Installation of scraper conveyor in fully mechanized coal face
