Processing technology for controlling flexural deformation of a belt conveyor drum shell

Abstract

This invention relates to a manufacturing process for controlling the deflection deformation of a belt conveyor roller, comprising the following steps: material selection and pretreatment; roller rolling using a three-roll plate rolling machine, with deflection compensation control devices applied at both ends of the upper roller to apply a reverse loading force to counteract roller deflection deformation; axial reinforcement rings installed inside the roller, with the spacing between the reinforcement rings gradually increasing from the middle to both ends; assembling and welding the machined connecting plates to both ends of the roller; using segmented back welding for longitudinal seams and multi-layer multi-pass welding for circumferential seams, with intermediate idler rollers and end retaining rings used to control deformation during welding; and immediately performing high-frequency vibration aging treatment after welding; overall annealing or partial tempering of the roller to eliminate residual stress; precision machining using the inner holes of the connecting plates at both ends as a reference; interference fit between the shaft and hub using expansion sleeves; and finally, dynamic balancing correction. This invention effectively reduces the deflection deformation of the roller roller, improving its bending stiffness and operational stability.

Description

Technical Field

[0001] This invention relates to the field of belt conveyor manufacturing technology, and in particular to a processing technology for controlling the flexural deformation of belt conveyor drum bodies. Background Technology

[0002] Belt conveyors are key equipment for the continuous transport of bulk materials and are widely used in industries such as mining, metallurgy, ports, power, and chemicals. As the core transmission component of a belt conveyor, the rollers bear significant alternating stress, and their design structure and manufacturing process are essential for ensuring the normal operation of the equipment. Rollers mainly come in two structural forms: cast and welded. Welded rollers are more widely used and come in more varieties on belt conveyors.

[0003] In actual operation, the main failure mode of the drive drum is weld cracking caused by alternating tensile and compressive deformation of the drum body during rotation. During operation, the radial deformation along the axis of the drum is consistent with the theoretical deformation result of the fixed beams at both ends, that is, the radial deformation is the largest in the center of the drum shell and gradually decreases towards both ends. When the belt conveyor starts, the tension is at its maximum, and the tension force is proportional to the driving force, which causes the pressure on the drum to increase rapidly in a short period of time. At the same time, the rotational acceleration of the drum reaches its maximum value at startup, resulting in a sudden increase in torque on the drum, which in turn leads to drum deformation. When the drum body undergoes flexural deformation, it can cause the conveyor belt to deviate, or even lead to serious accidents such as belt tearing and drum cracking.

[0004] The existing processing technology for roller bodies mainly has the following problems:

[0005] First, the rolling process of the cylinder lacks pre-control measures for flexural deformation. During the rolling process of a traditional three-roll plate rolling machine, the rollers deform under stress, which easily leads to the end of the cylinder being pressed into a local bulge shape. This is especially true for small-diameter, thick-walled cylinders, which require a large rolling pressure due to their small diameter, high material yield strength, and large length, resulting in more significant deformation of the rollers.

[0006] Second, deformation control during welding is insufficient. The weld quality and deformation of the welded rollers significantly affect the smooth operation of the belt conveyor. Uneven heat input, welding shrinkage stress, and improper welding sequence during welding can all lead to radial and axial bending deformation of the roller. In the existing process, the straightness and diameter deviations at both ends of the welded roller are significantly out of tolerance, resulting in frequent acceptance with compromises or scrapping.

[0007] Third, there is a lack of systematic residual stress relief technology. After welding, there is a large amount of residual welding stress inside the cylinder. If it is not effectively relieved, the residual stress will be superimposed on the working stress during operation, accelerating the cylinder's bending deformation and weld cracking.

[0008] Fourth, the clamping and positioning accuracy in the finishing process is insufficient. In traditional processes, the alignment benchmark is not uniform during the finishing of the cylinder, making it difficult to ensure that the installation center and the cylinder rotation center are concentric. This results in the roundness and cylindricity of the finished cylinder exceeding the tolerance, further aggravating the deflection deformation during operation.

[0009] Fifth, the structural design lacks targeted flexural reinforcement measures. Most existing drum bodies are single-shell structures without reinforcement structures in key locations, resulting in insufficient bending stiffness.

[0010] To address the aforementioned problems, this invention provides a processing technology for controlling the deflection deformation of belt conveyor rollers. Through a systematic control of the entire process, from material selection, pre-rolling control, welding deformation control, stress relief, precision machining positioning to structural reinforcement, the deflection deformation of the rollers is effectively reduced, thereby improving the operational stability and service life of the rollers. Summary of the Invention

[0011] The present invention aims to address the shortcomings of the prior art by providing a processing technology for controlling the flexural deformation of the drum body of a belt conveyor.

[0012] To achieve the above objectives, the present invention adopts the following technical solution:

[0013] A processing technology for controlling the deflection deformation of a belt conveyor drum includes the following steps:

[0014] Step 1: Material Selection and Pretreatment

[0015] Structural steel plates with a yield strength ≥345MPa were selected and cut after leveling.

[0016] Step Two: Cylinder Rolling and Anti-Deformation Pre-Control

[0017] The plate is rolled using a three-roll plate rolling machine. Deflection compensation control devices are installed at both ends of the upper roll to apply reverse loading force. After rolling, the plate is rounded.

[0018] Step 3: Setting and assembling the reinforcing ring:

[0019] Two to six reinforcing rings are axially arranged inside the cylinder, with the spacing between the reinforcing rings gradually increasing from the middle to both ends;

[0020] Step 4: Receiving, Processing, and Assembly:

[0021] After ultrasonic flaw detection, the receiving plate is processed and then assembled and welded to the inner walls of both ends of the cylinder.

[0022] Step 5: Control of welding deformation at longitudinal and circumferential seams:

[0023] The longitudinal seam adopts the segmented back welding method, and the circumferential seam adopts multi-layer multi-pass welding. During the welding process, intermediate rollers and end retaining rings are set to control deformation.

[0024] Step 6: Post-weld heat treatment to eliminate residual stress:

[0025] Perform overall annealing or local tempering treatment on the drum;

[0026] Step 7: Finish machining and precision control:

[0027] Align with the inner holes of the end connection plates at both ends as the reference, and perform boring and turning operations;

[0028] Step 8: Locking assembly connection and assembly:

[0029] Adopt the locking assembly method to achieve interference connection between the shaft and the hub;

[0030] Step 9: Dynamic balance correction:

[0031] Carry out static balance test and dynamic balance test in sequence.

[0032] In Step 2, the reverse loading force applied by the upper roll deflection compensation control device is 10%-20% of the rated rolling pressure.

[0033] In Step 2, the cylindricity error of the cylinder after round correction is ≤1mm.

[0034] In Step 3, when the drum length L ≤ 1500mm, 2 reinforcing rings are provided; when 1500mm < L ≤ 2500mm, 3-4 reinforcing rings are provided; when L > 2500mm, 5-6 reinforcing rings are provided.

[0035] In Step 3, the thickness of the reinforcing ring is 0.8-1.2 times the wall thickness of the cylinder, and the width of the reinforcing ring is 2-4 times the wall thickness of the cylinder.

[0036] In Step 5, the backstep welding method divides the longitudinal seam into several sections, each section has a length of 200-300mm, and welding is performed alternately from the middle to both ends.

[0037] In Step 5, the circumferential seam adopts a U-shaped groove with a groove angle of 60°-70°, for multi-layer and multi-pass welding, the thickness of each weld layer shall not exceed 3mm, and the interlayer temperature is controlled at 150-250°C.

[0038] In Step 5, immediately after each weld is completed, it is treated with a high-frequency vibration aging device, with a vibration frequency of 20-50Hz, an amplitude of 0.5-2mm, and a treatment time of 5-15 minutes.

[0039] In Step 6, the overall annealing treatment process is: heat to 580 to 620°C at a heating rate of ≤80°C / h, hold for 2 to 4 hours, cool in the furnace to below 300°C at a cooling rate of ≤100°C / h, then take it out of the furnace for air cooling.

[0040] In step seven, the precision control standards for finishing are as follows: inner diameter tolerance of the cylinder is grade H8, bearing seat size tolerance is grade h6, keyway symmetry is ≤0.02mm, cylinder cylindricity does not exceed 50% of the diameter tolerance, and cylinder roundness error is ≤0.5mm.

[0041] The beneficial effects of this invention are: through a systematic deformation control method throughout the entire process, this invention can effectively reduce the deflection deformation of the drum body, improve the bending stiffness and operational stability of the drum, reduce the deflection deformation in the middle of the drum body by more than 40% compared with the traditional process, and control the roundness error within 0.5mm. Detailed Implementation

[0042] The principles and features of the present invention are described below with reference to specific embodiments. These embodiments are for illustrative purposes only and are not intended to limit the scope of the invention. The advantages and features of the present invention will become clearer from the following description.

[0043] 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.

[0044] The present invention will be further described below with reference to specific embodiments:

[0045] A processing technology for controlling the deflection deformation of a belt conveyor drum includes the following steps:

[0046] Step 1: Material Selection and Pretreatment

[0047] (1) The cylinder material is Q345B low alloy structural steel with a yield strength ≥345MPa, ensuring that the cylinder has sufficient strength and resistance to deformation. For corrosive working environments, 304L or 316L stainless steel is selected. After the steel plates arrive at the factory, chemical composition analysis and mechanical property testing are carried out to ensure that they meet the design requirements.

[0048] (2) Before cutting the steel plate, it shall be leveled to eliminate the residual stress and unevenness of the plate itself. The cutting accuracy shall be controlled as follows: the difference in the width of the scribing line ≤ 1 mm, and the perpendicularity error between the long side and the short side ≤ 0.5 mm. Sufficient cutting allowance shall be reserved in the length direction: when the diameter of the roller is ≥ 600 mm, 300 mm shall be reserved on one side; when the diameter is < 600 mm, 250 mm shall be reserved on one side.

[0049] Step Two: Cylinder Rolling and Anti-Deformation Pre-Control

[0050] (1) A three-roll plate bending machine is used for progressive bending and rolling of the steel plate. Before rolling, deflection compensation control devices are arranged at both ends of the upper roll to apply reverse loading force to both ends of the upper roll, so that the upper roll generates pre-deformation opposite to the working deflection direction, so as to counteract the deflection deformation caused by the stress of the roll shaft during the rolling process.

[0051] (2) Before rolling the cylinder shell, the indenter tire must be used for indenter treatment. The radius of the indenter tire shall be close to the inner circle radius of the cylinder shell, and the length of the pressed arc shall not be less than 1 / 8 of the circumference. The R position of the rolling head of the cylinder shell shall be inspected with a 120° arc template, and the clearance shall be ≤ 0.3mm.

[0052] (3) Spot welding fixation is carried out when the butt clearance reaches 2-3mm, the length of the spot welding seam is 10-15mm, and the spot welding spacing is 300-400mm.

[0053] (4) After the rolling of the cylinder shell is completed, rounding treatment is carried out, and an internal support type rounding tooling is used to apply radial force from the inside of the cylinder for rounding. After rounding, the roundness error is ≤ 1mm.

[0054] Step 3: Setting and assembly of reinforcing rings:

[0055] (1) According to the diameter and length of the drum, 2-6 reinforcing rings are axially arranged inside the cylinder. The arrangement principle of the reinforcing rings is that the spacing between the reinforcing rings at the middle position is smaller than that at the two end positions, that is, the spacing between every two adjacent reinforcing rings gradually increases from the middle position of the cylinder to the two ends respectively. Specifically, when the drum length L ≤ 1500mm, 2 reinforcing rings are arranged; when 1500mm < L ≤ 2500mm, 3-4 reinforcing rings are arranged; when L > 2500mm, 5-6 reinforcing rings are arranged.

[0056] (2) The cross-sectional shape of the reinforcing ring is rectangular or T-shaped, the thickness of the reinforcing ring is 0.8-1.2 times the wall thickness of the cylinder, and the width of the reinforcing ring is 2-4 times the wall thickness of the cylinder.

[0057] (3) The reinforcing ring and the inner wall of the cylinder are connected by fillet welds. Before welding, a deformation-resistant coating is applied on the contact surface between the reinforcing ring and the cylinder. The welding sequence is to weld the middle reinforcing ring first, and then weld towards the two ends in sequence, so as to control the cumulative deformation during the welding process.

[0058] Step 4: Machining and assembly of the connection disc:

[0059] (1) The connection disc is a cast steel part. Ultrasonic flaw detection shall be carried out before machining to ensure no casting defects. During machining, the non-riser surface is taken as the reference surface, the outer circle of the connection disc is aligned, and the riser surface, outer circle and inner hole are roughly turned.

[0060] (2) The non-riser surface is turned with the riser surface as the reference surface, and a welding groove is turned on the non-riser surface. The web position of the connection disc is integrally machined, and the roughness reaches Ra25.

[0061] (3) Assemble the processed connector with the inner walls of both ends of the cylinder. Before assembly, machine positioning steps at the welding points on both ends of the inner wall of the cylinder. After fully positioning the connector with the positioning steps, weld. CO2 gas shielded welding is used for the root pass, and then submerged arc automatic welding is used for the cover pass.

[0062] Step 5: Control of welding deformation at longitudinal and circumferential seams:

[0063] (1) Longitudinal seam welding of cylinder: CO2 gas shielded welding or submerged arc automatic welding is adopted. Before welding, arc-starting plates and arc-extinguishing plates are set at both ends of the weld. The welding sequence adopts the segmented back welding method, dividing the longitudinal seam into several segments, and welding alternately from the middle to both ends. Each segment is 200-300mm long to disperse the welding heat input and reduce welding deformation.

[0064] (2) Circumferential welding between the cylinder and the connecting plate: U-shaped groove is adopted, with a groove angle of 60°-70° and a blunt edge height of 1-2mm. Welding adopts multi-layer and multi-pass welding, with the thickness of each weld layer not exceeding 3mm, and the interpass temperature is controlled at 150-250℃.

[0065] (3) During the welding process, intermediate rollers are set inside the cylinder to control the lateral bending deformation of the cylinder; steel retaining rings are set at both ends of the cylinder to control the radial deformation of the cylinder.

[0066] (4) After each weld is completed, the weld area is immediately subjected to vibration treatment using a high-frequency vibration aging device. The vibration frequency is 20-50Hz, the amplitude is 0.5-2mm, and the treatment time is 5-15 minutes to release the instantaneous stress of welding.

[0067] Step Six: Post-weld heat treatment to eliminate residual stress:

[0068] (1) After all welding work is completed, the drum body is subjected to overall annealing or artificial aging treatment to eliminate residual welding stress.

[0069] (2) Annealing process: The drum is loaded into the heat treatment furnace and heated to 580-620℃ at a heating rate of ≤80℃ / h. The holding time is 2-4 hours (calculated based on 1 hour of holding time for every 25mm of drum wall thickness). Then, it is cooled to below 300℃ with the furnace at a cooling rate of ≤100℃ / h, and then removed from the furnace and air-cooled to room temperature.

[0070] (3) For large rollers that cannot be annealed as a whole, a tracked far-infrared heater is used to perform local tempering treatment on each weld. The heater is wrapped around the weld and heated to 550-600℃. The temperature is maintained for 1-2 hours, and then covered with insulation cotton for slow cooling.

[0071] (4) After heat treatment, the cylinder is subjected to hardness testing and ultrasonic testing to ensure that the weld area has uniform hardness (HB≤280) and no internal defects.

[0072] Step 7: Finishing and Precision Control

[0073] (1) Using the inner holes of the end plates of the cylinder as the positioning reference, a dial indicator is clamped on the boring bar. The dial indicator is used as the reference for rough machining to make the alignment. The accuracy is ≤0.5mm.

[0074] (2) When turning around and boring the inner hole of the other end of the receiving plate, strictly follow the above steps to re-align the boring and ensure that the hub holes at both ends are concentric.

[0075] (3) When turning the outer diameter of the cylinder, use the process equipment to align the two hub holes with the center line to ensure that the installation center is concentric with the cylinder rotation center.

[0076] (4) Precision control standards for finishing: the inner diameter tolerance of the cylinder is controlled at grade H8; the bearing position size tolerance is controlled at grade h6; the keyway symmetry is ≤0.02mm; the cylinder cylindricity does not exceed 50% of the diameter tolerance; the cylinder roundness error is ≤0.5mm.

[0077] (5) After finishing, check the minimum wall thickness and wall thickness difference of the roller: at a distance of 100mm from the circumferential seam, avoid the longitudinal circumferential seam by 50mm, divide the roller into 4 lines at 90° intervals, and measure the wall thickness at 4 points on each line. The minimum value should be greater than the design minimum wall thickness, and the wall thickness difference should be less than the specified value.

[0078] Step 8: Expansion sleeve connection and assembly:

[0079] (1) After welding the web, hub and cylinder into one piece and performing precision machining, the shaft and hub are assembled by using an expansion sleeve connection method.

[0080] (2) Before fitting the expansion sleeve, clean the surface of the hub hole and journal to ensure that there is no oil or impurities. Push the expansion sleeve between the hub hole and the journal, and tighten the locking screw evenly according to the torque value specified by the expansion sleeve manufacturer, so that the inner and outer rings of the expansion sleeve expand radially to form an interference fit.

[0081] (3) After the expansion sleeve connection is completed, check that the radial runout of the shaft is ≤0.05mm and the axial runout is ≤0.03mm.

[0082] Step Nine: Dynamic Balancing Correction

[0083] (1) After the roller assembly is completed, a static balance test is performed, and the accuracy level is not lower than G40.

[0084] (2) After the static balance is qualified, the dynamic balance test is carried out. At the rated speed, the remaining imbalance is controlled within 2g·kg.

[0085] (3) During the dynamic balance test, the axial runout of the roller is monitored to be ≤0.1mm and the radial runout is monitored to be ≤0.08mm. Specific Implementation Example 1:

[0087] Taking the Φ800×1400mm drive drum of a belt conveyor in a mine as an example, it is manufactured using the processing technology of this invention.

[0088] Step 1: Select Q345B low-alloy structural steel plate with a thickness of 20mm. After the steel plate arrives at the factory, it undergoes chemical composition analysis and mechanical property testing, with a measured yield strength of 365MPa. After leveling, the steel plate has a scribing width difference of 0.6mm, a perpendicularity error of 0.3mm, and a 300mm allowance for trimming on one side along the length.

[0089] Step Two: A three-roll plate rolling machine is used for rolling. Hydraulic deflection compensation devices are installed at both ends of the upper roll, applying a reverse loading force of 15% of the rated rolling pressure. The radius of the pressure head is selected to be 98% of the inner radius of the cylinder, and the length of the pressing arc is 1 / 6 of the circumference. The gap at the radius R of the 120° arc template is checked to be 0.2mm. When the gap reaches 2.5mm, spot welding is performed, with a weld length of 12mm and a spacing of 350mm. After rounding, the roundness error is 0.6mm.

[0090] Step 3: The drum is 1400mm long, and three reinforcing rings are installed inside the drum. The middle reinforcing ring is located at the axial midpoint of the drum, and the two outer reinforcing rings are 300mm and 500mm from the midpoint, respectively. The reinforcing rings have a rectangular cross-section, a thickness of 18mm (0.9 times the drum wall thickness), and a width of 50mm (2.5 times the drum wall thickness). The reinforcing rings are welded to the inner wall of the drum using fillet welds, with the middle reinforcing ring welded first, followed by welding towards both ends.

[0091] Step 4: The receiving plate is made of ZG310-570 cast steel and has no defects detected by ultrasonic testing. Using the non-riser surface as a reference, the entire flange is machined to Ra25. Positioning steps, 2mm deep and 10mm wide, are machined at both ends of the inner wall of the cylinder. The receiving plate is then welded to the positioning steps after they are fully positioned.

[0092] Step 5: The longitudinal seam is welded using a segmented back-welding method, divided into 5 segments, each 250mm long, alternating from the middle to both ends. The circumferential seam uses a U-shaped bevel with a 65° angle and a 1.5mm blunt edge, employing multi-layer, multi-pass welding, with each layer 2.5mm thick, and the interpass temperature controlled at 200℃. An intermediate support roller is installed inside the cylinder, and steel retaining rings are installed at both ends. Each weld is immediately subjected to high-frequency vibration aging treatment after welding, with a vibration frequency of 35Hz, an amplitude of 1mm, and a treatment time of 10 minutes.

[0093] Step Six: Place the entire roller into the heat treatment furnace, heat it to 600℃ at a rate of 70℃ / h, hold it at that temperature for 3 hours, then cool it down to 280℃ at a rate of 80℃ / h, and remove it from the furnace for air cooling. After heat treatment, the hardness of the weld area is HB240-260, and ultrasonic testing shows no defects.

[0094] Step 7: Alignment using the inner holes of the end plates as a reference, with an accuracy of 0.4mm. After finishing, the inner diameter tolerance of the cylinder is H8 grade, the bearing seat dimensional tolerance is h6 grade, the keyway symmetry is 0.015mm, the cylindricity is 40% of the diameter tolerance, and the roundness error is 0.4mm. Wall thickness inspection: minimum value 21.2mm (design minimum wall thickness 20mm), wall thickness difference 0.6mm.

[0095] Step 8: Using an expansion sleeve connection, tighten the locking screws evenly to a torque of 120 N·m. After assembly, the radial runout of the shaft is 0.03 mm, and the axial runout is 0.02 mm.

[0096] Step 9: Static balance accuracy reaches G40, dynamic balance remaining imbalance is 1.5g·kg, axial runout is 0.06mm, and radial runout is 0.05mm.

[0097] After processing using the above process, the maximum deflection at the center of the drum body was verified by finite element analysis to be 0.82 mm under the design load, which is 40.6% lower than that of the traditional process (1.38 mm), thus meeting the design requirements. Specific Implementation Example 2:

[0099] Taking a Φ1200×2200mm redirecting roller of a belt conveyor in a port as an example, it is manufactured using the processing technology of this invention.

[0100] Step 1: Select 304L stainless steel plate with a thickness of 25mm. After leveling, the width difference of the scribing line is 0.8mm, and the perpendicularity error is 0.4mm.

[0101] Step 2: The upper roller deflection compensation device applies a reverse loading force of 18% of the rated winding pressure. The radius of the pressure head is selected as 97% of the inner radius of the cylinder, and the length of the pressing arc is 1 / 5 of the circumference. After rounding, the roundness error is 0.7mm.

[0102] Step 3: The roller is 2200mm long and has 4 reinforcing rings, spaced 350mm, 450mm, and 550mm apart from the center to both ends. The reinforcing rings are 22mm thick and 60mm wide.

[0103] Steps four through nine: Perform the joint processing, welding, heat treatment, precision machining, expansion sleeve connection, and dynamic balance correction in the same manner as in Specific Embodiment 1.

[0104] After testing, the roundness error of the finished cylinder was 0.45 mm, and the cylindricity was 35% of the diameter tolerance. The remaining unbalance after dynamic balancing was 1.8 g·kg. Finite element analysis verified that the maximum deflection deformation in the middle was 1.05 mm, which is 42.3% lower than that of the traditional process (1.82 mm).

[0105] This invention establishes a complete process chain for controlling flexural deformation, from material selection, pre-rolling control, welding deformation control, stress relief, precision machining positioning to structural reinforcement. Practical verification shows that the roller body processed using this invention exhibits a reduction of over 40% in mid-section flexural deformation compared to traditional processes, with the roundness error controlled within 0.5mm.

[0106] This invention employs an upper roller deflection compensation control device in the rolling process. By applying reverse loading forces at both ends of the upper roller, it effectively counteracts the deflection deformation of the roller shaft of the rolling machine under working load, thereby controlling the shape error of the cylinder rolling process from the source.

[0107] The present invention rationally sets the number of reinforcing rings according to the length of the drum and adopts a non-uniform arrangement with denser rings in the middle and sparser rings at both ends, so that the area with the greatest bearing capacity in the middle of the drum receives stronger support and effectively reduces the axial bending deformation of the drum.

[0108] This invention comprehensively utilizes multiple methods, such as segmented back welding, intermediate roller support, end retaining ring constraint, interlayer temperature control, and high-frequency vibration aging, to control welding deformation to a minimum.

[0109] This invention effectively eliminates residual welding stress through overall annealing or partial tempering, thus avoiding accelerated deformation and weld cracking caused by the superposition of residual stress and working stress.

[0110] The present invention has been described above with reference to specific embodiments. 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 processing method for controlling the flexural deformation of a belt conveyor drum shell, characterized in that, comprising the following steps: Step 1: Material selection and pretreatment: Select structural steel plates with a yield strength ≥ 345MPa, and perform blanking after leveling treatment; Step 2: Cylinder rolling and pre-control of reverse deformation: Roll using a three-roll plate bending machine, set deflection compensation control devices at both ends of the upper roll to apply reverse loading force, and perform round correction after rolling is completed; Step 3: Arrangement and assembly of reinforcing rings: Arrange 2 to 6 reinforcing rings axially inside the cylinder, and the spacing between adjacent reinforcing rings gradually increases from the middle to both ends; Step 4: Machining and assembly of connection discs: Machine the connection discs after ultrasonic flaw detection, and assemble and weld them to the inner walls at both ends of the cylinder; Step 5: Welding deformation control for longitudinal seams and circumferential seams: Adopt the backstep welding method for longitudinal seams, and adopt multi-layer and multi-pass welding for circumferential seams, and arrange intermediate support rollers and end snap rings to control deformation during the welding process; Step 6: Post-weld heat treatment to eliminate residual stress: Perform overall annealing or local tempering treatment on the drum; Step 7: Finish machining and precision control: Perform alignment using the inner holes of the connection discs at both ends as the reference, and carry out boring and turning machining; Step 8: Expansion sleeve connection and assembly: Adopt an expansion sleeve mode to perform interference connection between the shaft and the hub; Step 9: Dynamic balance correction: Carry out static balance test and dynamic balance test in sequence.

2. A processing method for controlling the flexural deformation of a belt conveyor drum shell according to claim 1, characterized in that, In Step 2, the reverse loading force applied by the upper roll deflection compensation control device is 10%-20% of the rated rolling pressure.

3. A processing method for controlling the flexural deformation of a belt conveyor drum shell according to claim 1, characterized in that, In Step 2, the roundness error of the cylinder after round correction is ≤ 1mm.

4. A processing method for controlling the flexural deformation of a belt conveyor drum shell according to claim 1, characterized in that, In Step 3, when the drum length L ≤ 1500mm, 2 reinforcing rings are arranged; when 1500mm < L ≤ 2500mm, 3-4 reinforcing rings are arranged; when L > 2500mm, 5-6 reinforcing rings are arranged.

5. The processing technology for controlling the deflection deformation of a belt conveyor drum body according to claim 1, characterized in that, In Step 3, the thickness of the reinforcing ring is 0.8-1.2 times the wall thickness of the cylinder, and the width of the reinforcing ring is 2-4 times the wall thickness of the cylinder.

6. The processing technology for controlling the deflection deformation of a belt conveyor drum body according to claim 1, characterized in that, In Step 5, the backstep welding method divides the longitudinal seam into several segments, each segment has a length of 200-300mm, and welding is performed alternately from the middle to both ends.

7. The processing technology for controlling the deflection deformation of a belt conveyor drum body according to claim 1, characterized in that, In Step 5, the circumferential seam adopts a U-shaped groove with a groove angle of 60°-70°, the thickness of each weld pass in multi-layer and multi-pass welding does not exceed 3mm, and the interlayer temperature is controlled at 150-250°C.

8. The processing technology for controlling the deflection deformation of a belt conveyor drum body according to claim 1, characterized in that, In Step 5, immediately after each weld is completed, it is treated with a high-frequency vibration aging device, with a vibration frequency of 20-50Hz, an amplitude of 0.5-2mm, and a treatment time of 5-15 minutes.

9. The processing technology for controlling the deflection deformation of a belt conveyor drum body according to claim 1, characterized in that, In Step 6, the overall annealing treatment process is: heat to 580-620°C at a heating rate of ≤ 80°C / h, hold the temperature for 2-4 hours, cool in the furnace at a cooling rate of ≤ 100°C / h to below 300°C, then take it out of the furnace for air cooling.

10. The processing technology for controlling the deflection deformation of a belt conveyor drum body according to claim 1, characterized in that, In Step 7, the finish machining precision control standards are: the inner diameter tolerance of the cylinder is H8 grade, the dimensional tolerance of the bearing position is h6 grade, the symmetry of the keyway is ≤ 0.02mm, the cylindricity of the cylinder does not exceed 50% of the diameter tolerance, and the roundness error of the cylinder is ≤ 0.5mm.