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Bucket elevator common faults and solutions

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Update time : 2022-11-18 17:24:21
Bucket elevator including belt bucket elevator, plate chain bucket elevator, chain bucket elevator and other several, is a kind of vertical lifting equipment widely used in agricultural processing plants and food bureaus, has the advantages of large lifting height, stability, small floor area and good sealing, suitable for lifting powder and small block materials.
The following are some common failures of the device during use
The hopper belt is slipping
(1) Bucket hoists use the frictional torque between the hopper belt and the head-wheel drive shaft to lift materials; lack of an ax to grind in the hopper belt will cause it to slip. At this time, the machine should stop immediately and adjust the tensioning device to tighten the hopper belt. If the tensioning device cannot make the hopper belt fully tensioned, it indicates that the tensioning device travel is too short, should be adjusted again.
The correct solution is to untie the hopper belt joint, adjust the tension device on the bottom wheel to the highest position, put the hopper belt in by the head of the hoist, pass through the head wheel and the bottom wheel, and connect the end to the end, so that the hopper belt will be tensioned but not tensioned. The tensioning device is then fully tensioned. At this time, the unutilized tensioning stroke of the adjusting screw of the tensioning device should not be less than 50% of the full stroke.
(2) hoist overload When the hoist is overloaded, the resistance moment increases, causing the hopper belt to slip. At this time should reduce the amount of material feeding, and strive to feed evenly. If you reduce the feeding amount, still can not improve the skid, it may be the material accumulation in the machine seat too much or the hopper is stuck by the tutor, should be stopped for inspection, troubleshooting.
(3) The inner surface of the head wheel drive shaft and hopper belt is too smooth than the inner surface of the smooth head wheel drive shaft and hopper belt, so that the friction between the two is reduced, resulting in the slide of the hopper belt. At this time, the inner surface of the drive shaft and hopper belt can be coated with a layer of glue to increase the friction force.
(4) Head wheel and bottom wheel bearing rotation is not good head wheel and bottom wheel bearing rotation is not good, resistance moment increases, causing the hopper belt skid. At this time you can disassemble, wash and refuel or replace the bearing.
Hopper belt goes astray
(1) The head wheel and the bottom wheel drive shaft installation is not correct the head wheel and the bottom wheel drive shaft installation is mainly reflected in the following aspects: first, the head wheel and the bottom wheel drive shaft in the same vertical plane and not parallel; Second, the two transmission shafts are installed in a horizontal position and not in the same vertical plane; Three is that the two transmission shafts are parallel, in the same vertical plane and not horizontal. At this time, the hopper belt deviates, which is easy to cause the impact between the hopper and the barrel and the tear of the hopper belt.Stop immediately and troubleshoot.The drive shaft of the head wheel and the bottom wheel is installed in the same vertical plane, but also in the horizontal position. The vertical deviation of the center line of the machine is not more than 2mm at the height of 1000mm, and the accumulation deviation is not more than 8mm.
(2) The hopper belt joint is not straight hopper belt joint does not mean that after the hopper belt is combined, the edge line of the hopper belt is not in the same straight line. When working, the hopper belt is tight and loose, so that the hopper belt moves sideways to the tight side, resulting in deviation, resulting in insufficient hopper material, incomplete discharge, increased return, decreased productivity, serious cause the hopper belt card edge, tear. At this time, stop, correct the joint and connect.

Excessive return of material
Hoist material return refers to the phenomenon that the material is not completely discharged out of the machine in the unloading position, and some materials are returned to the elevator base. In the lifting operation, if the lifting machine returns too much material, it is bound to reduce the production efficiency, increase the power consumption and the crushing rate of materials. The reasons for the feeding are as follows :(1) the hopper running speed is too fast to lift different materials, the hopper running speed is different: generally promote dry powder and grain, the speed is about 1~2m/s; When lifting bulk materials, the speed is 0.4~0.6m/s; When lifting wet powder and grain, the speed is 0.6~0.8m/s. Too high speed, discharge in advance, resulting in material return. At this time, the speed of the hopper should be reduced appropriately according to the lifting of the material to avoid the return of material.
(2) The unloading tongue plate of the nose outlet is not properly installed, and the tongue plate is too far away from the unloading position of the hopper, which will cause the material return. The position of the tongue plate should be adjusted in time to avoid backfeeding.
Fall of hopper
Hopper falling off refers to the phenomenon that the hopper falls off from the hopper belt during production. There will be abnormal noise when the hopper falls. It is necessary to stop and check in time.Otherwise, it will lead to more deformation and falling off of the hopper. At the hopper connection, the hopper belt is torn.The main reasons for the fall of the hopper are:
(1) Too much feed too much feed, resulting in material accumulation in the frame, lifting resistance increases, the hopper running is not smooth, is the direct cause of hopper fall off, deformation. At this time, the machine should stop immediately, pull out the insert plate under the base, discharge the accumulation in the base, replace the new hopper, and then start the production.
(2) The position of the feed port is too low. Generally, when the hoist is in production, the hopper will take the material from the feed port by itself. If the position of the feed port is too low, it will cause the hopper to have no time to take the material, and most of the material will enter the frame, resulting in the hopper to scoop the material. The material is block, it is easy to cause the hopper deformation, fall off. At this time, the position of the feed port should be adjusted to the bottom wheel center line.
(3) The material of the hopper is not good, the strength is limited, the bearing parts of the hopper hoist have higher requirements for its material, and the installation should try to choose the material with good strength. Generally, the hopper is welded or stamped with ordinary steel plate or galvanized plate, and its edge is hemmed or involved in lead wire to enhance the strength of the hopper.
(4) The accumulation in the frame is not removed when the machine is started. In production, there is often a sudden power failure or other reasons and the shutdown phenomenon. If the accumulation in the frame is not removed when the machine is started again, it is easy to cause the hopper to be affected too much and break off. Therefore, between stopping and starting, the accumulated material scraps in the frame must be removed to avoid falling off the hopper. In addition, regularly check whether the hopper is firmly connected with the hopper belt. When screws are found loose, falling off and hopper skew and damage, they should be repaired or replaced in time to prevent greater accidents.
Hopper belt torn
Hoist hopper belts are usually canvas belts, sometimes with tape and chains. One of the most serious problems is that canvas tape and tape are prone to tearing due to a combination of faults. Generally, the hopper belt deviation and the hopper shedding process are the most likely to cause the tear of the hopper. The cause should be thoroughly found out in time and the fault should be eliminated. In addition, the material mixed with foreign bodies with sharp edges will also split the hopper belt. Therefore, in the production, steel wire mesh or magnet should be installed at the feed port to prevent large foreign bodies from falling into the frame.
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Rules for safe operation of belt conveyors Rules for safe operation of belt conveyors
Feb .08.2023
Conditions for belt conveyor operators:
You have to have professional training to get on the job. Be familiar with the structure, performance, working principle, communication and control integrated system principle and inspection test method of the belt conveyor used, be able to maintain the belt conveyor, and be able to correctly deal with general faults.
Belt conveyor operation process:
1, in the operation of the operator is strictly prohibited to take the belt conveyor, when in use is not allowed to use the belt conveyor to transport equipment and heavy materials.
2. Check the good condition and fastening condition of all parts before operation, and confirm that there is no problem before formal operation.
3, the belt conveyor motor and switch within 20 meters near the gas concentration in the air reaches 1.5%, must stop working. Cut off power and evacuate personnel.
Belt conveyor equipment maintenance:
1. When the maintenance head is unloading the roller part, the upper mouth of the coal bunker must be strictly blocked.
2. When the belt conveyor is running, it is forbidden to clean the floating coal near the head and tail roller.
3, in the belt conveyor maintenance, troubleshooting or do other work, must close the conveyor control switch, hang up the warning sign, and press the emergency stop button.
4. When dealing with conveyor belt deviation, it is strictly prohibited to contact conveyor belt directly with hands, feet and other parts of the body.
5, often check the belt conveyor tunnel fire and spray dust removal facilities, and keep in good condition.
Safe operation rules of belt conveyor:
1, fixed conveyor should be installed on a fixed basis according to the prescribed installation method. Before the mobile conveyor is officially put into operation,  the wheels should be wedged with triangular wood or braked with brakes. In order to avoid walking in the work, there are multiple conveyor parallel operation, between the machine and the machine, between the machine and the wall should be one meter channel.
2. Before the belt conveyor is used, it is necessary to check whether each running part, belt buckle and bearing device are normal, and whether the protective equipment is complete. The tension of the tape must be adjusted to the right degree before starting.
3, the belt conveyor should be no-load start. Wait for normal operation before feeding. No feeding before driving.
4. When several conveyors run in series, they should start from the unloading end and start in sequence. After all the normal operation, can be put into the material.
5, in the operation of the belt deviation phenomenon, should stop the adjustment, not reluctantly use, so as to avoid wear edge and increase the load.
6. The working environment and the temperature of the material to be delivered shall not be higher than 50℃ or lower than -10℃.
7. No pedestrians or passengers on the conveyor belt.
8. Stop feeding before stopping, and wait for unloading of material on the belt before stopping.
9, belt conveyor motor must be well insulated. Do not pull on the mobile conveyor cable. The motor should be grounded reliably.
10. It is strictly prohibited to pull the belt by hand when the belt slips, so as to avoid accidents.
Large dip Angle conveyor anticorrosive coating requirements Large dip Angle conveyor anticorrosive coating requirements
Feb .08.2023
Large dip Angle belt machine coating requirements for anti-corrosion coating suitable for cold climate environment, winter should meet the requirements of cold and anti-freezing.
1. Surface treatment requirements
1) The surface of the steel structure of the belt conveyor shall be sandblasted to meet the national standard Sa2.5 level, remove dust, remove oil stains with cleaning agent, keep the bottom surface clean and dry, and then spray anti-rust paint. (The abrasive used is dry quartz sand with a particle size of 0.3 ~ 1.5mm).
2) Welding slag, powder coating, arc dust, residual edge and burr from mechanical processing are not allowed on the surface of welded structural parts.
3) Casting, forging surface uneven or other surface concealer caused by sandblasting to try to smooth, fill or appropriate treatment.
4) The surface of the coating to be recoated should be kept clean, dry and free of any dirt.
5) Where the processing or welding primer is damaged, it should be repainted after the primer, and then the matching medium coat or top coat.
2. Large dip Angle belt machine anticorrosive coating requirements
1.1 Paint film thickness:
Primer: epoxy zinc-rich primer, airless spray, 50μm, recoating interval 2h;
Medium coating: epoxy cloud iron antirust paint, airless spray, 100μm, recoating interval of 10h;
Top coat: acrylic rubber top coat, airless spray, 50μm, recoating interval 4h.
1.2 Requirements:
1) The interval between the metal surface after rust removal and the primer is generally no more than 6h. If rust has been rusted before painting, it should be cleaned or cleaned again.
2) Local airless spraying can not be used, brush coating can be used, brush coating (can be multiple times) film thickness must reach the specified film thickness.
3: corrosion prevention standards
1) The anticorrosion grade of the anticorrosion system shall be above medium, and the thickness of the dry film of the coating shall reach the thickness specified in this Agreement.
2) Preservative life: 5 ~ 8 years.
4: Acceptance standard
1) After surface treatment, the steel surface is almost white, no visible grease, dirt, oxide skin, rust and other sundries.
2) After coating epoxy zinc-rich primer, the standard film thickness is 50μm, the film adhesion is good, no leakage coating, pinhole, bubble, crack, fall off, flow hanging and other defects, the surface is kept dry and clean.
3) After coating the epoxy cloud iron anti-rust paint, the standard film thickness is 100μm, the adhesion between the coatings is good, no leakage coating, pinhole, bubble, crack, fall off, flow hanging and other defects, the surface is kept dry and clean.
4) After coating acrylic top paint, reach the standard film thickness: indoor 100μm, outdoor 200μm, good adhesion between coatings, no color infiltration phenomenon, no bubbles on the surface, flow hanging and other defects, the surface has a certain luster.
5. Detection method
1) Testing instrument: electromagnetic dry film thickness measuring instrument.
2) Detection method: The electromagnetic dry film thickness measuring instrument is used to measure one point every 10m2 and one point every 3 ~ 4m of thin bodies such as pipes. The three-point average is the actual film thickness of the coating, and the three-point error should be less than 20% of the specified standard film thickness.
3) Appearance detection: the appearance of the coating can be observed with the naked eye or a five-fold magnifying glass.
4) The film thickness mentioned above is dry film thickness.
Belt conveyor 6 parts installation requirements and maintenance points Belt conveyor 6 parts installation requirements and maintenance points
Feb .07.2023
The belt conveyor has the advantages of simple structure and large conveying capacity, and is widely used in mining, metallurgy and other fields. Improve the reliability and stability of belt conveyor mainly from the equipment installation and operation maintenance.
1. Structure of belt conveyor Common belt conveyor structure is mainly composed of driving device, roller, tensioning device, brake device, conveyor belt and roller and other parts. The driving device includes a driving drum, a reducer, a motor and a brake. Reducer from the structure of the form of the main points of direct axis and parallel axis reducer.
2. The belt conveyor installation sequence measurement and setting out → foundation acceptance → nose equipment transportation → tensioning device transportation → middle frame transportation → tail transportation → nose equipment installation and alignment → tensioning device installation and alignment → middle frame installation → tail installation → belt vulcan display → single machine trial operation → trial operation.
3. Installation technical requirements of belt conveyor
1) Installation of conveyor belt
Conveyor belt is the main component of belt conveyor, through the whole length of the belt conveyor. Reducing the failure rate of conveyor belt is an important method to improve the life of belt conveyor and reduce the running cost.
In the process of conveyor belt installation, to ensure the quality of conveyor belt joint must be flat, non-adhesive, non-bubbling, cohesive, smooth; The noncoincidence degree of the center line of the two rolls conveyor belt is less than 3mm. During the operation of the belt machine, the conveyor belt shall not slip or run off, and the amount of run off shall not exceed 5% of the bandwidth.
2) Installation of driving device
The driving device provides traction when the belt conveyor runs normally, and is the core of the belt conveyor.
When the driving device is installed, it is necessary to ensure that the center line of the belt conveyor is perpendicular to the axis of the driving drum, and in the center line of the width of the driving drum; Ensure that the levelness of the driving drum and the steering drum shaft should not exceed 0.3‰, the non-coincidence degree between the width center line of the driving drum and the width center line of the reversing drum and the longitudinal center line of the belt conveyor is not more than 2mm, and the non-perpendicularity between the axis line of the driving drum and the reversing drum and the longitudinal center line of the belt conveyor is not more than 2‰ of the drum width.
When the driving device is installed and adjusted, ensure that the motor has no abnormal sound, no abnormal heating and vibration; There is no abnormal sound and vibration phenomenon during the test run of the reducer, the box surface temperature is not beyond the standard, the tooth surface is not excessive wear, the fastening bolt is not loose; The brake and the backstop have no abnormal sound and heating phenomenon, and the rotating pin shaft is not stuck or abnormal wear.
3) Installation of idlers and racks
The roller is installed on the frame to support the conveyor belt, so that the overhang of the conveyor belt does not exceed the specified requirements. The roller is required to rotate flexibly and perpendicular to the center line of the belt conveyor, and the roller has no abnormal sound and stuck phenomenon. The center line of the frame and the longitudinal center line of the belt conveyor do not overlap more than 3mm; The relative height difference between the two channels of steel on the rack is not more than 3mm.
4) Installation of tension device
The tension device can compensate the elastic and plastic deformation of the conveyor belt, so that the conveyor has enough tension to prevent the belt conveyor from slipping. The rope of the tensioning device shall not rust and break the wire, and the conveyor belt shall not be relaxed. As far as possible, it is installed on the no-load branch near the driving drum, which is conducive to starting and braking without skid phenomenon; Try to install in the conveyor belt tension minimum place, so as to reduce the tension.
5) Installation of protection devices
The anti-skid protection device is installed on the return belt of the belt conveyor. For the fixed belt conveyor, the anti-skid protection device is installed between the head unloading roller and the driving roller; The pile protection shall be installed at the lap joint of two belt conveyors. The protective contact shall be hung in front of the unloading roller, and the hanging height of the protective contact shall not be higher than the lower edge of the unloading roller; The running off protection is installed in pairs, and the head and tail of the machine are installed in one group, and fixed on the belt conveyor frame using a special bracket; The temperature sensor shall be installed near the driving drum of the belt conveyor, and the temperature probe shall be close to the outer wall of the main drum.
6) Multiple belt conveyor lap installation
When multiple belt conveyors are bonded, the material falls from the unloading place of the previous belt conveyor to the receiving place of the rear belt conveyor. When the belt conveyor is installed, the drop between the unloading drum of the former belt conveyor and the rear belt conveyor should be kept at about 1m. Ensure that the material can be smoothly unloaded to the receiving belt conveyor, without too much impact.
4. Maintenance of the belt conveyor The workplace of the belt conveyor shall be kept clean to ensure that the motor, hydraulic coupler and reducer have good heat dissipation conditions; In the running process of belt conveyor, try to avoid frequent start; Before working, we should carefully check whether the hydraulic coupler leaks oil, whether the steel wire rope loosens, and whether the conveyor belt runs off. Large materials are not allowed to be loaded directly, so as not to damage the conveyor belt. Regular maintenance of belt conveyor is conducive to improving the service life of belt conveyor and reducing the failure rate of belt conveyor. Ensure the belt conveyor idler seal ring filled with grease, idler rotation flexible; Reducer, hydraulic coupling and other devices do not leak oil; Regularly check whether the fastening parts are firm and reliable; Check conveyor belt joints regularly, and repair or replace them in time.
The early installation is the basis of the stable operation of the belt conveyor, should strictly implement the installation technical requirements, from the source of hidden dangers. Maintenance is the guarantee of stable operation of belt conveyor. Therefore, it is necessary to strictly grasp the overhaul system and overhaul workers' business skills to prevent the failure of belt conveyor.
Analysis of main structure composition and abnormal problems of belt conveyor Analysis of main structure composition and abnormal problems of belt conveyor
Feb .07.2023
Belt conveyor is mainly composed of frame, conveyor belt, belt roller, tensioning device, transmission device and so on. Belt conveyor is a kind of common machinery in production and life, because of its conveying capacity, relatively small power consumption, can adapt to a variety of materials and other advantages, it is widely used.
Installation sequence of belt conveyor:
Before the belt conveyor installation needs to do a good job of organization and technical disclosure. Specifically: establish a reasonable installation management organization, clarify the responsibilities of relevant responsible personnel; Do a good job of technical disclosure, such as construction, drawing design, operating specifications and acceptance standards; Provide technical training on the use, transportation and installation of related equipment to ensure the installation quality.
The installation sequence of the belt conveyor is as follows: preparation before installation → measuring and setting out to determine the location and Angle of the belt conveyor → acceptance of roadway foundation → transportation of the head, tensioning equipment, intermediate support, tail and other equipment → head installation and alignment → tensioning device installation and alignment → middle support installation → tail installation → belt laying and connecting → commissioning → trial run.
Analysis and treatment of abnormal noise problem and belt slip:
Noise caused by idlers deviating from the center. Belt conveyor in the process of running, the roller is easy to appear noise device, and will be accompanied by periodic vibration. On the one hand, the noise is due to the uneven thickness of the seamless steel tube wall in the process of manufacturing idlers, which makes the idlers produce relatively large centrifugal force. On the other hand, because in the process of processing the idlers, there is a large deviation between the middle of the bearing holes at both ends and the center of the outer circle, which will also produce relatively large centrifugal force, resulting in abnormal noise. To deal with the problem of abnormal noise, first check the bearing of the belt conveyor, if the bearing is damaged, then replace the bearing, if the bearing is not damaged, then take other ways to deal with it.
For the shaft of the coupling caused by different noise problems, the position of the motor reducer can be adjusted accordingly to solve.
For the abnormal noise problems brought by the drum, it is generally caused by bearing damage, so the replacement of bearings can be done. For the belt slip phenomenon, if it is the hammer tension belt machine slip. You can add counterweight until the belt does not slip, but it needs to be noted that the addition can not be too much so as to avoid too much tension but affect the service life of the belt. If it is spiral tension or hydraulic tension belt machine slip problem. The tension force of the belt can be increased by adjusting the tension stroke. It should be noted that this treatment may cause deformation of the belt. When this problem occurs, the deformed belt can be cut off for subsequent operations.