What Is a Bucket Elevator?

Bucket elevator is a continuous conveying machine that uses a series of hoppers that are uniformly fixed to the endless traction member to lift the material vertically. Bucket elevators use a series of hoppers that are fixed to the traction chain or tape in a vertical or near Bulk material is transported upwards in the vertical direction ^[1] . Divided into three types of ring chain, plate chain and belt.

Bucket style

The hopper lifts the material from the storage below.

Bucket elevator consists of hopper,

Bucket elevator is a kind of vertical conveying material conveying equipment. It has the advantages of simple structure, low maintenance cost, high conveying efficiency, high lifting height, stable operation and wide application range. ^[2]

Bucket elevators include belt bucket elevators, plate chain bucket elevators, and chain bucket elevators, which are widely used in agricultural processing plants and grain bureaus. It has the advantages of stability, small footprint and good sealability, which is suitable for lifting and transporting powdery and small block materials.

The following are several common faults in the use of this device:

Bucket elevator bucket slip

(1) The bucket elevator uses the frictional moment between the hopper belt and the head wheel drive shaft to lift the material. The insufficient tension of the hopper belt will cause the hopper belt to slip. At this time, stop immediately and adjust the tensioning device to tighten the hopper belt. If the tensioning device cannot fully tension the hopper belt, it indicates that the stroke of the tensioning device is too short and should be readjusted.

Bucket elevator

The correct solution is: Unlock the hopper belt joint, adjust the tensioning device on the bottom wheel to the highest position, put the hopper belt from the head of the hoist, pass through the head wheel and the bottom wheel, and connect the end to end to make the hopper The belt is in a state of being tensioned without being tensioned. The tensioning device is then fully tensioned. At this time, the unused tensioning stroke of the adjusting screw of the tensioning device should not be less than 50% of the full stroke.

(2) Overload of the hoist When the hoist is overloaded, the drag torque increases, causing the hopper belt to slip. At this time, the feeding amount of the material should be reduced, and the feeding should be strived for uniformity. If the slippage cannot be improved after reducing the feeding amount, it may be that there is too much material accumulation in the machine seat or the hopper is stuck by the instructor, and the machine should be stopped and inspected to eliminate the fault.

(3) The inner surface of the head wheel drive shaft and the hopper belt is too smooth. The inner surface of the head wheel drive shaft and the hopper belt is too smooth, which reduces the friction between the two and causes the hopper belt to slip. At this time, a layer of glue can be applied to the inner surfaces of the drive shaft and the hopper belt to increase friction.

(4) The head and bottom wheel bearings are not rotating. The head and bottom wheel bearings are not rotating. The resistance torque increases, causing the hopper belt to slip. At this time, you can remove and refuel or replace the bearing.

Bucket elevator bucket deviation

(1) Improper installation of the drive wheels of the front and bottom wheels The incorrect installation of the drive wheels of the front and bottom wheels is mainly reflected in the following aspects:

First, the drive shafts of the head wheels and the bottom wheels are in the same vertical plane and are not parallel;

The second is that both transmission shafts are installed in a horizontal position and not in the same vertical plane;

Third, the two transmission shafts are parallel, in the same vertical plane and not horizontal.

At this time, the hopper belt deviates, which may easily cause the hopper to hit the barrel and tear the hopper belt. Stop the machine immediately to remove the fault. Make sure that the drive shafts of the head wheel and the bottom wheel are installed in the same vertical plane, and both are in the horizontal position. The vertical deviation of the center line of the whole machine at a height of 1000 mm does not exceed 2 mm, and the accumulated deviation does not exceed 8 mm.

(2) The hopper belt joint is not correct The hopper belt joint is not the same as the edge line of the hopper belt after the hopper belt is combined. When working, the hopper belt is tight and loose at the same time, causing the hopper belt to move sideways to the tight side, causing deviations, resulting in insufficient hopper loading, incomplete discharge, increased return, increased productivity, and serious hopper belt jamming when serious Tearing. Stop the machine at this time, correct the connector and connect it.

Too much bucket bucket return

The return of the hoisting machine refers to the phenomenon that the materials are not completely discharged outside the machine at the unloading position, and some materials return to the hoisting machine base.

In the lifting operation, if the hoist returns too much material, it will inevitably reduce production efficiency, increase power consumption and material crushing rate. There are several reasons for the large number of returns:

(1) The speed of the hopper is too fast. The hoist lifts different materials, and the speed of the hopper is different: Generally, the speed is about 1 ~ 2m / s when lifting dry powder and pellets; when lifting bulk materials, the speed is 0.4 ~ 0.6m / s; when lifting wet powders and granules, the speed is 0.6 ~ 0.8m / s. If the speed is too large, the unloading will advance, which will cause the returning. At this time, the speed of the hopper should be appropriately reduced according to the material being lifted to avoid material return.

(2) The discharge tongue plate at the exit of the machine head is not installed properly. The tongue plate is too far away from the hopper discharge position, which will cause material return. The position of the tongue plate should be adjusted in time to avoid material return.

Bucket elevator bucket falls off

Hopper dropout refers to the phenomenon that the hopper falls off the hopper belt during production. When the hopper is dropped, an abnormal sound will be generated. It must be shut down and inspected in time. Otherwise, it will cause more hoppers to deform and fall off. At the position where the hopper is connected, the hopper belt is torn.

The main reasons for the hopper to fall off are:

(1) Too much feeding Too much feeding will cause the material to accumulate in the machine base, increase the lifting resistance, and the hopper will not run smoothly, which is the direct cause of the hopper falling off and deformation. At this time, stop the machine immediately, withdraw the lower board of the machine base, discharge the accumulation in the machine base, replace the new hopper, and start production. At this time, reduce the feeding amount and strive for uniformity.

(2) The position of the feeding port is too low. Generally, when the hoist is in production, the hopper takes the material coming in from the feeding port by itself. If the position of the inlet is too low, the hopper will not be able to pick up the material, and most of the material will enter the machine base, causing the hopper to pick up the material. The material is lumpy, which can easily cause the hopper to deform and fall off. At this time, the position of the inlet should be adjusted above the centerline of the bottom wheel.

(3) The material of the hopper is not good, and the load-carrying parts of the hopper hoist with limited strength have high requirements for its material. When installing, try to choose a material with good strength. Generally, the hopper is welded or stamped with ordinary steel or galvanized sheet, and its edges are folded or rolled into lead wire to enhance the strength of the hopper.

(4) Accumulations in the machine base are not cleared during the start-up. In production, there are often sudden power outages or other reasons to stop the machine. If you restart the machine and do not clear the accumulations in the machine base, it is easy to cause hoppers The impact is too large to break off. Therefore, between the shutdown and the start-up, the accumulated material debris in the machine base must be removed to prevent the hopper from falling off. In addition, regularly check whether the hopper and the hopper belt are firmly connected. If you find that the screws are loose, falling off, and the hopper is skewed or broken, etc., it should be repaired or replaced in time to prevent larger accidents.

Bucket elevator bucket with tear

The elevator hopper belt is usually a canvas belt, and sometimes tape and chain are also used. Under the combined effect of various faults, the canvas belt and tape are prone to tear, which is one of the most serious faults. Generally, the deviation of the hopper belt and the shed of the hopper are the most likely to cause the hopper to tear. The reason should be promptly and comprehensively investigated and the fault should be eliminated. In addition, sharp-edged foreign materials mixed in the material will also crack the hopper belt. Therefore, in production, a wire mesh or a suction stone should be installed at the feed port to prevent large foreign objects from falling into the machine base.