Three-point progressive jacking method for replacing slewing bearing of bucket-wheel cantilever reclaimer

Abstract

The application is a three-point progressive jacking method for replacing the slewing bearing of a bucket-wheel cantilever reclaimer, comprising jacking point bearing capacity calculation and three-point progressive jacking method; three-point progressive jacking is adopted in the jacking process, the horizontal conditions of the three points and the jacking height are observed at any time, a 15mm-thick steel pad is added for protection when the jacking height is increased by 15mm, so as to ensure the balance and safety of the whole machine during the jacking process; the old bearing is removed when the jacking height is appropriate; when the new bearing is installed, the upper structure of the bucket-wheel cantilever reclaimer is successfully aligned with the new bearing, and then the upper structure of the bucket-wheel cantilever reclaimer is completely lowered, finally, the whole machine is recovered and debugged. The application provides a relatively perfect construction method for replacing the slewing bearing of a bucket-wheel cantilever reclaimer, the gravity center is well controlled during jacking, the installation precision is high, and the construction difficulty is reduced.

Description

Technical Field

[0001] This invention relates to the technical field of bucket wheel cantilever reclaimers, and more particularly to a three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer. Background Technology

[0002] Bucket wheel cantilever reclaimers are material handling equipment used in bulk cargo terminals to reclaim and transport coal from stockpiles. They mainly consist of a traveling mechanism, a slewing mechanism, a pitching mechanism, a bucket wheel mechanism, and a cantilever belt conveyor, performing traveling, slewing, pitching, and reclaiming operations. Due to prolonged high-intensity operation, bucket wheel cantilever reclaimers may experience jamming, abnormal noises, and vibrations during slewing, leading to malfunctions. The primary cause of this is physical wear of the slewing bearings due to long-term high-intensity use. This issue poses a significant safety hazard, necessitating timely replacement of the slewing bearings.

[0003] An investigation into existing slewing bearing replacement processes revealed that current methods for replacing slewing bearings in bucket wheel cantilever reclaimers are inadequate, lacking standardized procedures and a comprehensive, systematic approach. Furthermore, the lifting section has a complex structure, making center-of-gravity control difficult; installation precision requirements are high, and construction is challenging. Summary of the Invention

[0004] The present invention aims to address the shortcomings of the prior art by providing a three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer.

[0005] To achieve the above objectives, the present invention adopts the following technical solution:

[0006] The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer involves the following steps:

[0007] S1. According to the design drawings of the bucket wheel cantilever reclaimer, three sets of lifting points are arranged at corresponding positions on the gantry frame of the bucket wheel cantilever reclaimer. The second and third lifting points are arranged symmetrically about the first lifting point.

[0008] S2. When the bucket wheel cantilever reclaimer moves to the maintenance position, it is anchored and clamped to the rail. The traveling wheels are fixed with iron wedges to prevent them from moving along the rail direction.

[0009] S3. Adjust the slewing angle to the position where the gantry and the three lifting points correspond vertically. Place the boom in a horizontal position and slew it to the right to 140°. After the three lifting points are aligned, select one set of wheels at the front and one set at the rear along the boom direction and measure the pressure of the traveling wheels. By adjusting the pitch angle of the bucket wheel cantilever reclaimer and measuring the pressure of the traveling wheels, confirm that the upper structure is in a balanced state.

[0010] S4. Remove the material guide funnel at the slewing bearing location to meet the needs of slewing bearing replacement; open the low-voltage distribution cabinet switch; mark and remove all power and control cables that affect the replacement of the slewing bearing, and place them neatly in the cable chain chamber; remove the optical cables and mark the order in which the pigtails are inserted into the photoelectric converter.

[0011] S5. Verify the bearing capacity of the three lifting points and select lifting jacks that meet the requirements;

[0012] S6. Before lifting, reconfirm that there are no objects around the object that can be lifted that may affect its upward movement, and mark any objects that have detached from each other so that they can be accurately positioned during reinstallation.

[0013] S7. Use jacks to lift and separate the upper structure of the bucket wheel cantilever reclaimer from the slewing bearing. Measure the elevation every 15mm of lifting and add a 15mm safety pad. Stop lifting when the height reaches 300mm.

[0014] S8. Remove the old slewing bearing, clean the bearing support surfaces of the gantry and slewing platform, and replace and tighten the new slewing bearing.

[0015] S9. The three jacks are lowered simultaneously. Under the unified command of the person in charge, they are lowered in an orderly manner in 15mm increments until they are 2mm away from the large bearing. After confirming that there is no deviation in all bolt holes of the slewing bearing, the jacks are lowered completely and simultaneously.

[0016] S10, Debugging and testing.

[0017] In step S5, the formula for verifying the bearing capacity of the three jacking points is as follows:

[0018] F1×X1=F2×X2+F3×X3;

[0019] F2=F3;

[0020] F1 + F2 + F3 = F;

[0021] in,

[0022] F1, F2, and F3 represent the bearing capacities of the three lifting points, respectively.

[0023] F represents the total weight of the upper structure of the bucket wheel cantilever reclaimer;

[0024] X1, X2, and X3 are the lever arm distances of the three lifting points, respectively.

[0025] The bearing capacities F1, F2, and F3 of the three lifting points are calculated according to the above three formulas. The maximum lifting force of the jack used for lifting shall not be less than the bearing capacities F1, F2, and F3 of the three lifting points.

[0026] In step S5, a jack with a maximum lifting force of 320t is selected.

[0027] In step S6, the objects affecting the upward displacement include the rotation limit switch, the detection switch, the hopper in the middle section, the lubrication pipeline, and the cable.

[0028] In step S7, when using jacks to lift and separate the upper structure of the bucket wheel cantilever reclaimer from the slewing bearing, first place three hydraulic jacks in the designated positions to confirm that the upper structure of the bucket wheel cantilever reclaimer is in a horizontal state. Then, the person in charge directs the lifting work of the three hydraulic jacks, and a dedicated person is assigned to monitor each lifting point.

[0029] In step S7, after the jacking position rises 15mm, the three points are checked to see if they are horizontal using a level, and the jacking height is measured with a tape measure to ensure that they are at the same elevation and to proceed to the next node simultaneously while ensuring safety.

[0030] In step S7, a level is used to monitor the jacking process. If any jacking point experiences settlement, the jacking operation is immediately terminated.

[0031] In step S7, after the jack is lifted into position, a 300mm thick steel pad is added to the top of the jack to form a rigid support.

[0032] In step S10, after the mechanical and electrical parts are restored, the control system is debugged, and individual action tests and signal tests are performed on each mechanism to check whether the feedback signals of all protection devices are normal. After the control system is debugged, a joint test run is conducted.

[0033] The beneficial effects of this invention are: This invention proposes a relatively complete construction method for replacing the slewing bearing of a bucket wheel cantilever reclaimer, which ensures good control of the center of gravity during jacking, high installation accuracy, and reduces construction difficulty. Attached Figure Description

[0034] Figure 1 This is a schematic diagram illustrating the principle of the present invention;

[0035] The following will describe in detail, with reference to the accompanying drawings, embodiments of the present invention. Detailed Implementation

[0036] The principles and features of the present invention are described below with reference to the accompanying drawings. The examples given are for illustrative purposes only and are not intended to limit the scope of the invention. The invention is described more specifically in the following paragraphs by way of example with reference to the accompanying drawings. The advantages and features of the invention will become clearer from the following description and claims. It should be noted that the drawings are in a very simplified form and use non-precise proportions, and are only used to facilitate and clarify the illustration of the embodiments of the invention.

[0037] It should be noted that when a component is described as "fixed to" another component, it can be directly on the other component or may have a component in between. When a component is considered "connected to" another component, it can be directly connected to the other component or may have a component in between. When a component is considered "set on" another component, it can be directly set on the other component or may have a component in between. The terms "vertical," "horizontal," "left," "right," and similar expressions used in this document are for illustrative purposes only.

[0038] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention pertains. The terminology used herein in the description of the invention is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0039] The present invention will be further described below with reference to the accompanying drawings and embodiments:

[0040] like Figure 1 As shown, the three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer involves the following steps:

[0041] S1. According to the design drawings of the bucket wheel cantilever reclaimer, three sets of lifting points are arranged at corresponding positions on the gantry frame of the bucket wheel cantilever reclaimer. The second and third lifting points are arranged symmetrically about the first lifting point.

[0042] S2. When the bucket wheel cantilever reclaimer moves to the maintenance position, it is anchored and clamped to the rail. The traveling wheels are fixed with iron wedges to prevent them from moving along the rail direction.

[0043] S3. Adjust the slewing angle to the position where the gantry and the three lifting points correspond vertically. Place the boom in a horizontal position and slew it to the right to 140°. After the three lifting points are aligned, select one set of wheels at the front and one set at the rear along the boom direction and measure the pressure of the traveling wheels. By adjusting the pitch angle of the bucket wheel cantilever reclaimer and measuring the pressure of the traveling wheels, confirm that the upper structure is in a balanced state.

[0044] S4. Remove the material guide funnel at the slewing bearing location to meet the needs of slewing bearing replacement; open the low-voltage distribution cabinet switch; mark and remove all power and control cables that affect the replacement of the slewing bearing, and place them neatly in the cable chain chamber; remove the optical cables and mark the order in which the pigtails are inserted into the photoelectric converter.

[0045] S5. Verify the bearing capacity of the three lifting points and select lifting jacks that meet the requirements;

[0046] The formulas for verifying the bearing capacity of the three lifting points are as follows:

[0047] F1×X1=F2×X2+F3×X3;

[0048] F2=F3;

[0049] F1 + F2 + F3 = F;

[0050] in,

[0051] F1, F2, and F3 represent the bearing capacities of the three lifting points, respectively.

[0052] F represents the total weight of the upper structure of the bucket wheel cantilever reclaimer;

[0053] X1, X2, and X3 are the lever arm distances of the three lifting points, respectively.

[0054] The bearing capacities F1, F2, and F3 of the three jacking points are calculated according to the above three formulas. The maximum jacking force of the jack used for jacking shall not be less than the bearing capacities F1, F2, and F3 of the three jacking points.

[0055] S6. Before lifting, reconfirm that there are no objects around the object to be lifted that may affect its upward movement, including the slewing limit switch, detection switch, hopper in the middle, lubrication pipeline, and cable. Mark any detached objects to ensure accurate positioning during reinstallation.

[0056] S7. Use jacks to lift and separate the upper structure and slewing bearing of the bucket wheel cantilever reclaimer.

[0057] When using jacks to lift and separate the upper structure of the bucket wheel cantilever reclaimer from the slewing bearing, first place three hydraulic jacks in the designated position to confirm that the upper structure of the bucket wheel cantilever reclaimer is in a horizontal state. Then, the person in charge directs the lifting work of the three hydraulic jacks, and a dedicated person is assigned to monitor each lifting point.

[0058] After the jacking position is raised by 15mm, check whether the three points are horizontal using a spirit level and measure the jacking height with a tape measure to ensure that they are at the same elevation and proceed to the next node simultaneously while ensuring safety.

[0059] Measure the elevation every 15mm and add a 15mm safety pad. Stop lifting when the height reaches 300mm.

[0060] A level is used to monitor the jacking process. If any jacking point shows signs of settlement, the jacking work must be terminated immediately.

[0061] After the jacks are lifted into position, 300mm thick steel pads are added to the top of the jacks to form rigid support.

[0062] S8. Remove the old slewing bearing, clean the bearing support surfaces of the gantry and slewing platform, and replace and tighten the new slewing bearing.

[0063] S9. The three jacks are lowered simultaneously. Under the unified command of the person in charge, they are lowered in an orderly manner in 15mm increments until they are 2mm away from the large bearing. After confirming that there is no deviation in all bolt holes of the slewing bearing, the jacks are lowered completely and simultaneously.

[0064] S10. After the mechanical and electrical parts are restored, the control system is debugged, and individual action tests and signal tests are performed on each mechanism to check whether the feedback signals of all protection devices are normal. After the control system is debugged, a joint test run is conducted. Specific Implementation Example 1:

[0066] According to the design drawings of the bucket wheel cantilever reclaimer, the slewing platform flange and the gantry edge are given as the lifting points, and a heavy-duty plate is attached.

[0067] Three sets of jacking points are arranged at corresponding positions on the gantry frame of the bucket wheel cantilever reclaimer. The total jacking weight F is 696t. 320t jacks are selected for the jacking operation.

[0068] The bucket wheel cantilever reclaimer travels to the maintenance position, anchors and clamps the rail, and the traveling wheels are fixed with iron wedges to prevent movement along the rail direction.

[0069] Adjust the slewing angle to align the gantry with the jacking point, ensuring the boom is horizontal. Rotate the boom to approximately 140° to the right, aligning the jacking point. Then, select one set of wheels at the front and rear of the boom and measure the pressure on the traveling wheels. Adjust the pitch angle of the bucket wheel cantilever reclaimer to confirm the balance of the upper structure.

[0070] The calculation process for verifying the bearing capacity of lifting points 1, 2, and 3:

[0071] Distance of lever arm at jacking point 1: X1 = 3.87m;

[0072] Distance of lever arm at jacking point 2: X2 = 2.95m;

[0073] Distance of lever arm at jacking point No. 3: X3 = 2.95m;

[0074] Bearing capacity calculation:

[0075] F1*X1=F2*X2+F3*X3;

[0076] F1*3.87=F2*2.95+F3*2.95;

[0077] F2=F3;

[0078] F1+F2+F3=696t;

[0079] The calculation yields:

[0080] F1 = 300t;

[0081] F2=198t;

[0082] F3=198t;

[0083] Conclusion: A 320t jack was selected to meet the requirements.

[0084] Before lifting, double-check that there are no objects around the object to be lifted that could affect its upward movement, such as slewing limit switches, detection switches, hoppers in the middle section, lubrication lines, cables, etc. Mark any detached parts to ensure accurate repositioning during reinstallation.

[0085] The upper structure and slewing bearing of the bucket wheel cantilever reclaimer were lifted and separated using 320t hydraulic jacks. Three hydraulic jacks were placed in their designated positions. After confirming the upper structure of the bucket wheel cantilever reclaimer was level, the overall supervisor directed the lifting operation of the three hydraulic jacks, with one person monitoring each lifting point. The three 320t hydraulic jacks were then placed at their respective lifting points, and the overall supervisor directed the lifting operation, with one person monitoring each lifting point.

[0086] After the jacking position is raised by 15mm, check that the three points are level using a spirit level and measure the jacking height with a tape measure to ensure they are at the same elevation. Proceed to the next step simultaneously, ensuring safety.

[0087] The elevation is measured every 15mm, and a 15mm safety pad is added. Lifting is stopped when the height reaches 300mm. A level is used to monitor the lifting process; if any point shows signs of settlement, the lifting operation is immediately terminated.

[0088] After the jacks are lifted into position, 300mm thick steel pads are added to the top of the jacks to form rigid support.

[0089] The replacement and tightening of the slewing bearing is complete.

[0090] The jacks are lowered synchronously under the unified command of the person in charge. They are lowered in an orderly manner in increments of 15mm until they are 2mm away from the large bearing. After confirming that there is no deviation in all bolt holes of the slewing bearing, the jacks are lowered completely synchronously.

[0091] Debugging and testing.

[0092] This invention proposes a relatively complete construction method for replacing the slewing bearing of a bucket wheel cantilever reclaimer. The method ensures good center of gravity control during jacking, high installation accuracy, and reduces construction difficulty.

[0093] The present invention has been described above by way of example with reference to the accompanying drawings. Obviously, the specific implementation of the present invention is not limited to the above-described manner. Any improvements made using the inventive concept and technical solution of the present invention, or direct application to other occasions without modification, are all within the protection scope of the present invention.

Claims

1. A three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer, characterized in that, The specific steps are as follows: S1. According to the design drawings of the bucket wheel cantilever reclaimer, three sets of lifting points are arranged at corresponding positions on the gantry frame of the bucket wheel cantilever reclaimer. The second and third lifting points are arranged symmetrically about the first lifting point. S2. When the bucket wheel cantilever reclaimer moves to the maintenance position, it is anchored and clamped to the rail. The traveling wheels are fixed with iron wedges to prevent them from moving along the rail direction. S3. Adjust the slewing angle to the position where the gantry and the three lifting points correspond vertically. Place the boom in a horizontal position and slew it to the right to 140°. After the three lifting points are aligned, select one set of wheels at the front and one set at the rear along the boom direction and measure the pressure of the traveling wheels. By adjusting the pitch angle of the bucket wheel cantilever reclaimer and measuring the pressure of the traveling wheels, confirm that the upper structure is in a balanced state. S4. Remove the material guide funnel at the slewing bearing location to meet the needs of slewing bearing replacement; open the low-voltage distribution cabinet switch; mark and remove all power and control cables that affect the replacement of the slewing bearing, and place them neatly in the cable chain chamber; remove the optical cables and mark the order in which the pigtails are inserted into the photoelectric converter. S5. Verify the bearing capacity of the three lifting points and select lifting jacks that meet the requirements; S6. Before lifting, reconfirm that there are no objects around the object that can be lifted that may affect its upward movement, and mark any objects that have detached from each other so that they can be accurately positioned during reinstallation. S7. Use jacks to lift and separate the upper structure of the bucket wheel cantilever reclaimer from the slewing bearing. Measure the elevation every 15mm of lifting and add a 15mm safety pad. Stop lifting when the height reaches 300mm. S8. Remove the old slewing bearing, clean the bearing support surfaces of the gantry and slewing platform, and replace and tighten the new slewing bearing. S9. The three jacks are lowered simultaneously. Under the unified command of the person in charge, they are lowered in an orderly manner in 15mm increments until they are 2mm away from the large bearing. After confirming that there is no deviation in all bolt holes of the slewing bearing, the jacks are lowered completely and simultaneously. S10, Debugging and testing.

2. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 1, characterized in that, In step S5, the formula for verifying the bearing capacity of the three jacking points is as follows: F1×X1=F2×X2+F3×X3; F2=F3; F1 + F2 + F3 = F; in, F1, F2, and F3 represent the bearing capacities of the three lifting points, respectively. F represents the total weight of the upper structure of the bucket wheel cantilever reclaimer; X1, X2, and X3 are the lever arm distances of the three lifting points, respectively. The bearing capacities F1, F2, and F3 of the three lifting points are calculated according to the above three formulas. The maximum lifting force of the jack used for lifting shall not be less than the bearing capacities F1, F2, and F3 of the three lifting points.

3. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 2, characterized in that, In step S5, a jack with a maximum lifting force of 320t is selected.

4. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 3, characterized in that, In step S6, the objects affecting the upward displacement include the rotation limit switch, the detection switch, the hopper in the middle section, the lubrication pipeline, and the cable.

5. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 4, characterized in that, In step S7, when using jacks to lift and separate the upper structure of the bucket wheel cantilever reclaimer from the slewing bearing, first place three hydraulic jacks in the designated positions to confirm that the upper structure of the bucket wheel cantilever reclaimer is in a horizontal state. Then, the person in charge directs the lifting work of the three hydraulic jacks, and a dedicated person is assigned to monitor each lifting point.

6. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 5, characterized in that, In step S7, after the jacking position rises 15mm, the three points are checked to see if they are horizontal using a level, and the jacking height is measured with a tape measure to ensure that they are at the same elevation and to proceed to the next node simultaneously while ensuring safety.

7. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 6, characterized in that, In step S7, a level is used to monitor the jacking process. If any jacking point experiences settlement, the jacking operation is immediately terminated.

8. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 7, characterized in that, In step S7, after the jack is lifted into position, a 300mm thick steel pad is added to the top of the jack to form a rigid support.

9. The three-point progressive jacking method for replacing the slewing bearing of a bucket wheel cantilever reclaimer according to claim 8, characterized in that, In step S10, after the mechanical and electrical parts are restored, the control system is debugged, and individual action tests and signal tests are performed on each mechanism to check whether the feedback signals of all protection devices are normal. After the control system is debugged, a joint test run is conducted.

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