A machining method of a roller for a main bearing of a heading machine, the roller, and the main bearing of the heading machine

Abstract

The present application relates to the technical field of machining, and particularly relates to a machining method of a roller for a main bearing of a heading machine, the roller and the main bearing of the heading machine, the machining method comprising the following steps: customizing a bar, blanking to obtain a blank of a single roller; soft turning to obtain a soft turning roller; heat treatment to obtain a heat treated roller with a surface hardness not less than 59HRC; hard turning to obtain a hard turning roller; rough grinding of a rolling surface to obtain a rough grinding roller; fine grinding of double end faces to meet length size requirements of the finished roller; fine grinding of the rolling surface to form an outer circle contour of the roller; super fine grinding to obtain a finished roller meeting contour accuracy and size accuracy. The machining method can realize machining of an ultra-large precision profile roller for the main bearing of the heading machine, ensure contour accuracy and size accuracy of the roller, and improve overall performance and service life of the main bearing.

Description

Technical Field

[0001] This invention relates to the field of machining technology, and in particular to a method for machining rollers for the main bearing of a tunneling machine, the rollers themselves, and the main bearing of the tunneling machine. Background Technology

[0002] The main bearing of a tunnel boring machine is a core component of tunnel boring equipment, and its performance directly affects the service life and reliability of the equipment. The rollers in the main bearing are key load-bearing elements. The rolling elements are often cylindrical rollers with an extra-large diameter to withstand high loads and impacts, and are modified to optimize the contact between the rollers and the raceway, reducing stress concentration and thus improving the bearing's fatigue life and load-bearing capacity.

[0003] The machining of rollers typically involves steps such as turning, heat treatment, and grinding. For example, the common machining method for small-sized rollers usually involves rough turning the outer contour first, followed by heat treatment (such as quenching and tempering) to improve hardness and wear resistance, and then grinding to form the desired contour shape (such as logarithmic curves or circular curves). However, ultra-large precision profiled rollers (diameter ≥ φ100mm and length ≥ 100mm) used in tunneling machines have large diameters, heavy weights, large grinding areas, large grinding allowances, and high requirements for contour accuracy and dimensional accuracy (GB / T 4661-2015 G1 grade), making their high-precision machining extremely technically challenging.

[0004] Therefore, it is necessary to provide a method for machining rollers for tunneling machine main bearings, as well as the rollers and the tunneling machine main bearings, to solve the above-mentioned technical problems. Summary of the Invention

[0005] The main objective of this invention is to provide a method for machining rollers for tunneling machine main bearings, the rollers themselves, and the tunneling machine main bearing. The machining method of this invention ensures the accuracy of the roller profile and dimensions, thereby improving the overall performance and service life of the main bearing. The specific technical solution is as follows: A method for machining rollers for the main bearing of a tunneling machine includes the following steps: Step 1: Customize the bar stock; Step 2: Unloading materials; Cut the material according to the preset cutting length to obtain a blank blank for a single roller; Step 3, soft carriage; The blank part is then soft-turned to obtain a soft-turned roller part; Step 4: Heat treatment; The soft-turned roller parts were heat-treated by 880±5°C bainitic quenching process and then tempered at 220±5°C to obtain heat-treated roller parts with a surface hardness of not less than 59HRC. Step 5, Hardening; Hard turning of heat-treated roller parts includes: First, machine the first end face of the heat-treated roller part; Using the first machined end face as the reference surface, the machining length is 2 / 3. The rolling surface, after machining, has a radial dimension of... ; The chamfer at the first end is machined using a five-segment circular arc chamfering method; wherein: The length of the roller component after hard turning. The diameter of the roller component after hard turning; Flip the roller component over and clamp the machined rolling surface; machine the second end face of the roller component, resulting in a roller component length of [length to be specified]. ; The remaining rolling surface is machined, and the radial dimension after machining is: ; The chamfer at the second end is processed using a five-segment circular arc chamfering method; Obtain hard rolling mill rollers; Step 6: Rough grinding of the rolling surface; The rolling surface of the hardened roller is rough ground to obtain a rough-ground roller; Step 7: Grind both end faces thoroughly; A vertical double-sided grinding machine is used to grind the two end faces of the rough grinding roller to meet the length requirements of the finished roller. Step 8: Fine grinding of the rolling surface; The rollers after fine grinding of the double end faces are cleaned; the outer circle contour of the rollers is finely ground using a CNC cylindrical grinding machine to form a logarithmic curve contour, and the machining allowance after fine grinding is controlled within the range of 0.001~0.008mm. Step Nine, Ultra-precision Research; The rolling surface of the precision-ground roller is subjected to ultra-precision treatment to make the roller roundness ≤0.0003mm and the roughness Ra≤0.08μm, so as to obtain the finished roller that meets the profile accuracy and dimensional accuracy.

[0006] Furthermore, the custom-made bar stock is made of rolled round steel, and the material is any one of 100CrMo7-3, 100CrMo7-4, and 100CrMnMoSi8-4-6. The diameter of the custom-made bar , This indicates the diameter of the finished roller; the allowable deviation for the diameter of custom-made bar stock is ±1mm. The length of the custom-made bar stock is 4000mm~6000mm; the out-of-roundness is ≤0.7mm; the curvature is ≤2.8mm / meter; and the total curvature is ≤15mm.

[0007] Furthermore, a high-speed saw is used to cut and blank the customized bar stock, with the saw blade speed set to ≥100 rpm / min; Preset cutting length , This indicates the length of the finished roller; the allowable deviation for the blanking dimension is ±1mm.

[0008] Furthermore, the blank part is subjected to soft turning, including: First, machine the first end face of the blank; Using the first machined end face as the reference surface, the machining length is 2 / 3. The rolling surface, after machining, has a radial dimension of... ;in: The length of the flexible roller component. The diameter of the flexible roller component; Chamfering at the first end This yields semi-finished soft-roller parts; The semi-finished roller assembly is flipped over, and the rolled surface after machining is clamped. The second end face is then machined, resulting in a roller assembly with a length of [length missing]. ; The remaining rolling surface is machined, and the radial dimension after machining is: ; Chamfering at the second end ; The soft-roller component is obtained.

[0009] Furthermore, a high-precision CNC horizontal lathe is used to machine the blank, and ceramic cutting inserts are selected as the cutting tools with a radius of 0.4mm. Diameter of flexible rolling elements , Indicates the diameter of the finished roller; Length of soft-roller components , Indicates the length of the finished roller; Chamfering of soft-roller parts , The value range is 1 to 3. This refers to the chamfering dimensions of the finished roller.

[0010] Furthermore, the five-segment chamfering method is specifically as follows: In order , , , , The tool path for machining the rounded chamfer is completed in the following sequence; where: This refers to the toolpath trajectory of the lathe tool. Chamfering for roller parts after hard turning; For end face and The transition arc, With end face and Tangent; yes The transition arc between the rolling surface number curve profile of the finished roller; This refers to the retraction toolpath of the lathe tool. The profile of the rolling surface number curve of the finished roller and Tangent.

[0011] Furthermore, and The point of tangency on the end face is tangency point one. and The point of tangency of the rolling surface number curve profile of the finished roller is point two, and the horizontal and vertical distances between point one and point two are both... , .

[0012] Furthermore, and The value is 0.4 ~0.6 , and The value is 0.3 ~0.8 .

[0013] Furthermore, during hard turning, the tool radius should be ≤0.8mm; Diameter of hard rolling mill rollers , Indicates the diameter of the finished roller. The value range is 0.25~0.5mm; Length of hard car rollers , Indicates the length of the finished roller. The value range is 0.15~0.3mm; chamfering of hard rollers , The value range is 1 to 3. This refers to the chamfering dimensions of the finished roller; The tool marks on the rolling surface of hard-machined rollers must be controlled to be ≤0.1mm.

[0014] Furthermore, a CNC centerless cylindrical grinder is used to rough grind the rolling surface of the hard-turned roller, wherein the rolling surface profile is taken from the middle. For straight lines, the rest follow the contour curve of the finished roller. Grinding is performed. The value range is 0.02~0.1mm; This indicates the effective length of the finished roller.

[0015] Diameter of coarse grinding roller , Indicates the diameter of the finished roller. The value range is 0.1~0.15mm.

[0016] Furthermore, a vertical double-sided grinding machine is used to grind the two end faces of the rough grinding roller. CBN grinding wheels are selected for the upper and lower discs, and the upper and lower grinding wheels rotate in opposite directions to uniformly correct the flatness and parallelism of the roller end faces.

[0017] Furthermore, a CNC cylindrical grinding machine is used to finely grind the outer diameter of the roller. The roller end face is limited by magnetic pole adsorption. Before processing, the roller processing position is used to vertically position and grind the surface of the magnetic pole tooling to ensure that the vertical difference between the surface of the magnetic pole tooling of the roller of this specification and the base set parallel to the roller axis is ≤0.001mm.

[0018] Furthermore, this also includes demagnetization; the rollers after fine grinding of the rolling surface are demagnetized to ensure that the residual magnetism is ≤0.3mT.

[0019] The present invention also provides a roller, which is processed by the method described above.

[0020] The present invention also provides a tunneling machine main bearing, wherein the rollers of the tunneling machine main bearing are rollers as described above.

[0021] The beneficial effects achieved by this solution are: (1) The present invention provides a method for machining rollers for main bearings of tunneling machines, including custom bar stock, blanking, soft turning, heat treatment, hard turning, rough grinding of rolling surface, fine grinding of double end face, fine grinding of rolling surface, and ultra-fine grinding of rolling surface; the method steps of this method can realize the machining of ultra-large precision modified rollers for main bearings of tunneling machines, ensure the accuracy of roller profile and dimensional accuracy, and improve the overall performance and service life of main bearings.

[0022] (2) In this invention, the five-segment circular arc chamfering method is used to process the circular arc chamfer during hard turning. The circular arc toolpath for tool entry / exit can avoid the step caused by tool setting error; through the transition arc and This can effectively avoid the formation of sharp corners and prevent damage caused by... Sharp edges that cannot be smoothly transitioned are prevented from peeling off due to stress concentration, thus avoiding premature bearing failure.

[0023] (3) In this invention, during rough grinding of the rolling surface, the middle of the rolling surface Internal grinding into a straight line removes tool marks from the previous hard-turned rolling surface. Simultaneously, it establishes a reference for the subsequent fine grinding process, preventing deviations in the finished product's convexity due to machining errors. This better ensures contour accuracy and minimizes batch diameter variations. The contours on both sides of the rolling surface follow the finished roller contour curve + Grinding is performed because the machining amount of ultra-large diameter convex rollers is large. This process removes a large machining allowance, which can improve production efficiency for subsequent fine grinding. Attached Figure Description

[0024] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on the structures shown in these drawings without creative effort.

[0025] Figure 1 This is a schematic flowchart illustrating the machining method of the rollers for the main bearing of a tunneling machine in this invention; Figure 2 This is a schematic diagram of the dimensions of the soft-car in this invention; Figure 3 This is a schematic diagram of the five-segment circular arc chamfering process in this invention; Figure 4 This is a schematic diagram of the rolling surface after rough grinding in this invention; Figure 5 This is a schematic diagram of the rolled surface after fine grinding in this invention; Figure 6 This is a schematic diagram of the finished roller in this invention.

[0026] The realization of the objective, functional features and advantages of the present invention will be further explained in conjunction with the embodiments and with reference to the accompanying drawings. Detailed Implementation

[0027] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0028] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0029] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly specified.

[0030] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixed," etc., should be interpreted broadly. For example, "fixed" can mean a fixed connection, a detachable connection, or an integral part; it can mean a mechanical connection or an electrical connection; it can mean a direct connection or an indirect connection through an intermediate medium; it can mean the internal communication of two components or the interaction between two components, unless otherwise explicitly limited. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0031] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible for those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0032] Example 1: This invention proposes a method for machining rollers for the main bearings of tunneling machines, see [link to relevant documentation]. Figure 1 It includes the following steps: Step 1: Customize the bar stock; The custom-made bar stock is made of rolled round steel, and the material is any one of 100CrMo7-3, 100CrMo7-4, and 100CrMnMoSi 8-4-6; the diameter of the custom-made bar stock is... , This indicates the diameter of the finished roller; the allowable deviation for the diameter of the custom bar stock is ±1mm; the length of the custom bar stock is 4000~6000mm; out-of-roundness ≤0.7mm; curvature ≤2.8mm / meter; total curvature ≤15mm; torsion is not allowed, and the ends should be neat.

[0033] Using custom-made bars (with superior material composition and properties) facilitates subsequent heat treatment and machining, laying the foundation for precision machining and finished product quality.

[0034] Step 2: Unloading materials; The blanks are cut according to a preset cutting length to obtain blanks for a single roller. In this invention, a high-speed saw is used to cut the customized bar stock, and the saw blade speed is set to ≥100 rpm / min (100 rpm / min in this embodiment). One roller blank is cut at a time, and the preset cutting length is... , This indicates the length of the finished roller; the allowable deviation for the blanking dimension is ±1mm.

[0035] For ultra-large diameter bars, high-speed sawing can ensure cutting efficiency. At the same time, compared with gas cutting, the cutting surface (roller end face) of sawing is more regular and flat, and will not form a large heat-affected zone and residual stress, thus not affecting the mechanical properties of the material.

[0036] Step 3, soft carriage; The blank workpiece is then machined using a soft turning technique to obtain a soft-turned roller part. In this invention, a high-precision CNC horizontal lathe is used to machine the blank workpiece, and ceramic cutting inserts with a tool radius of 0.4 mm are selected. The machining process is as follows: First, machine the first end face of the blank; Using the first machined end face as the reference surface, the machining length is 2 / 3. The rolling surface, after machining, has a radial dimension of... ;in: The length of the flexible roller component. The diameter of the flexible roller component; Chamfering at the first end This yields semi-finished soft-roller parts; The semi-finished roller assembly is flipped over, and the rolled surface after machining is clamped. The second end face is then machined, resulting in a roller assembly with a length of [length missing]. ; The remaining rolling surface is machined, and the radial dimension after machining is: ; Chamfering at the second end ; The soft-roller component is obtained.

[0037] In this invention, reference is made to Figure 2 : Diameter of flexible rolling elements , Indicates the diameter of the finished roller; Length of soft-roller components , Indicates the length of the finished roller; Chamfering of soft-roller parts , The value range is 1 to 3. This refers to the chamfering dimensions of the finished roller.

[0038] The material is removed by a soft turning process to prepare for heat treatment. Rounded corners (R-angle) are used instead of chamfered corners (C-angle) to effectively prevent cracks from forming at sharp corners during heat treatment.

[0039] Step 4: Heat treatment; The soft-turned roller parts were heat-treated by bainitic quenching at 880±5°C and then tempered at 220±5°C for 600±5 minutes to obtain heat-treated roller parts with a surface hardness of not less than 59HRC.

[0040] Heat treatment can effectively and significantly improve the rigidity, hardness, wear resistance, fatigue strength, and toughness of rollers.

[0041] Step 5, Hard turning; using a high-precision CNC horizontal lathe with carbide cutting tools, the rollers after heat treatment in the previous process are machined. The tool radius is ≤0.8mm, including: First, machine the first end face of the heat-treated roller part; Using the first machined end face as the reference surface, the machining length is 2 / 3. The rolling surface, after machining, has a radial dimension of... ; The chamfer at the first end is machined using a five-segment circular arc chamfering method; wherein: The length of the roller component after hard turning. The diameter of the roller component after hard turning; Flip the roller component over and clamp the machined rolling surface; machine the second end face of the roller component, resulting in a roller component length of [length to be specified]. ; The remaining rolling surface is machined, and the radial dimension after machining is: ; The chamfer at the second end is processed using a five-segment circular arc chamfering method; Obtain hard rolling mill rollers.

[0042] In this invention, the diameter of the hard-machined rollers , Indicates the diameter of the finished roller. The value range is 0.25~0.5mm; Length of hard car rollers , Indicates the length of the finished roller. The value range is 0.15~0.3mm; chamfering of hard rollers , The value range is 1 to 3. This refers to the chamfer dimensions of the finished roller. Chamfering for hard-machined rollers. The value of completely covers the value of the chamfer of the soft-roller parts, which means that the heat treatment black skin needs to be removed. The tool marks on the rolling surface of hard-machined rollers must be controlled to be ≤0.1mm.

[0043] In this invention, the five-segment circular arc chamfering method specifically refers to: See Figure 3 From bottom right to top left, follow the order. , , , , The tool path for machining the rounded chamfer is completed in the following sequence; where: This refers to the toolpath trajectory of the lathe tool. Chamfering for roller parts after hard turning; For end face and The transition arc, With end face and Tangent ( The point of tangency with the end face and and (The points of tangency are the same). yes The transition arc between the rolling surface number curve profile of the finished roller; This refers to the retraction toolpath of the lathe tool. The profile of the rolling surface number curve of the finished roller and Tangent (tangent at the same point).

[0044] See Figure 3 , and The point of tangency on the end face is tangency point one. and The profile of the rolling surface number curve of the finished roller is tangent point two, and the horizontal and vertical distances between tangent point one and tangent point two are both... , . To match the finished roller The dimension-related values ​​define the effective length of the end face and the rolling surface.

[0045] In this invention, and The value is 0.4 ~0.6 , and The value is 0.3 ~0.8 .

[0046] Using a circular arc toolpath for entry / exit can avoid steps caused by tool setting errors; through the transition arc and This can effectively avoid the formation of sharp corners and prevent damage caused by... The inability to smoothly transition and the resulting sharp edges should be avoided to prevent stress concentration and spalling, thereby preventing premature bearing failure.

[0047] Step 6: Rough grinding of the rolling surface; The rolling surface of the hard-turned roller is rough-ground to obtain a rough-ground roller. In this invention, a CNC centerless cylindrical grinder is used to rough-ground the rolling surface of the hard-turned roller. See also... Figure 4 The rolling surface profile is taken at the middle. Straight lines ( Indicates the effective length of the finished roller. The rest are based on the finished roller profile curve + Grinding is performed. The value range is 0.02~0.1mm; thus, a rough grinding roller is obtained. For example... Figure 4 As shown, this process only processes the rolling surface, and does not process the end face, meaning the workpiece length does not change.

[0048] middle of rolling surface Internal grinding into a straight line removes tool marks from the previous hard-turned rolling surface. Simultaneously, it establishes a reference for the subsequent fine grinding process, preventing deviations in the finished product's convexity due to machining errors. This better ensures contour accuracy and minimizes batch diameter variations. The contours on both sides of the rolling surface follow the finished roller contour curve + Grinding is performed because the machining amount of ultra-large diameter convex rollers is large. This process removes a large machining allowance, which can improve production efficiency for subsequent fine grinding. At the same time, because the outer diameter of this process is a straight line, the rotation posture of the workpiece in the hole of the planetary gear fixture of the grinding fixture is more stable when the double end face is finely ground in the next process. This avoids the roller tilting in the hole of the planetary gear fixture of the grinding fixture during the double end face grinding process due to poor outer contour, thereby avoiding the parallelism difference and uneven flatness of the end face.

[0049] After the rough grinding process, the diameter of the rough grinding rollers , Indicates the diameter of the finished roller. The value range is 0.1~0.15mm.

[0050] Step 7: Grind both end faces thoroughly; A vertical double-sided grinding machine is used to grind the two end faces of the rough grinding roller. CBN grinding wheels are used on the upper and lower grinding discs, and the upper and lower grinding wheels rotate in opposite directions to uniformly correct the flatness and parallelism of the roller end faces, ensuring that the parallelism difference is ≤0.003mm and the surface roughness Ra is ≤0.1μm. The rolling surface of the workpiece is not machined in this process; that is, the contour and diameter remain unchanged. At this point, the length dimension of the roller is completed.

[0051] In this invention, a vertical double-sided grinding machine is used for processing, which can process multiple rollers at once. The parallelism difference between the two end faces of each roller is good (end face parallelism difference ≤ 0.003 mm), and the surface roughness is good (surface roughness Ra ≤ 0.1 μm). The surface roughness of the rollers and the batch length variation of the roller gauge value meet the G1 grade requirements. At the same time, the good end face flatness provides a good end face positioning reference for subsequent fine grinding, so as to better ensure the contour accuracy of fine grinding and the batch diameter variation of the roller gauge value.

[0052] Step 8: Fine grinding of the rolling surface; The rollers, after double-end face grinding, are cleaned. An automatic roller cleaning machine with automatic loading and unloading function is used to clean the rollers after the previous double-end face grinding process. After the previous double-end face grinding process, extremely fine grinding debris remains on the roller surface. This debris residue on the end face or surface may affect the outer surface quality of the rollers in subsequent production processes. The automatic loading and unloading function can effectively reduce the manual labor intensity caused by high-frequency loading and unloading; better surface quality provides a good end face positioning reference for subsequent fine grinding, thereby better ensuring the contour accuracy of fine grinding and the batch diameter variation of the roller diameter gauge value.

[0053] See Figure 5 The outer diameter of the roller is precision ground using a CNC cylindrical grinding machine to form a logarithmic curve profile. The machining allowance after precision grinding is controlled to be [specific value missing]. , The value range is 0.001~0.008mm.

[0054] In this invention, the precision CNC cylindrical grinding machine should have a robot loading and unloading function. The grinding wheel dresser should be integrated with the reference of the roller machining position. The roller end face is limited by magnetic pole adsorption. Before machining, the roller machining position performs vertical positioning and grinding on the surface of the magnetic pole tooling to ensure that the vertical difference between the surface of the magnetic pole tooling of the roller of this specification and the base set parallel to the roller axis is ≤0.001mm. The machine tool should have advanced online detection function (such as MARPOSS). Two to three constant temperature water tanks are added to the side of the machine tool. The volume of each constant temperature water tank is not less than 500L. The water tank adopts a circulating water inlet and outlet form to ensure that the temperature difference of the grinding fluid does not exceed 0.2°C.

[0055] Precision CNC cylindrical grinding machines can perform high-precision contour forming, providing a better roundness foundation for subsequent ultra-precision grinding processes. Robotic loading and unloading of rollers improves positioning and effectively avoids initial grinding errors caused by manual loading and unloading; it also effectively reduces the risk of bumps and scratches during roller loading and unloading, significantly reducing manual labor intensity. The integration of the grinding wheel dresser and the roller machining position's reference further improves the positional accuracy of the roller's contour curve, ensuring the forming accuracy of the roller's logarithmic contour curve. Magnetic adsorption is used to limit the roller end face, also ensuring the forming accuracy of the roller's logarithmic contour curve. Because the previous process precisely grinded both end faces, the roller's end face quality, flatness, and parallelism are all of high quality. Therefore, this method effectively ensures that the axial runout (SDW) of the roller end face to the roller axis meets the G1 level. In-line measurement within the machine tool effectively controls the grinding wheel feed and dressing, ensuring that the diameter gauge value of this batch of rollers meets the batch diameter variation and satisfies the G1 level. The additional constant temperature circulating water tank is to ensure the temperature of the cutting fluid is stable, and to avoid the measurement error caused by temperature difference in the precision online measurement module, which would result in a large variation in the diameter of the roller gauge batch.

[0056] After the rollers have been precision ground, they should be demagnetized to ensure that the residual magnetism is ≤0.3mT. Excessive residual magnetism in the rollers can cause premature bearing failure; therefore, demagnetization is necessary to ensure the bearing's service life.

[0057] Step Nine, Ultra-precision Research; The roller rolling surface after precision grinding is then subjected to ultra-precision treatment to ensure that the roller roundness is ≤0.0003mm, the surface roughness Ra is ≤0.08μm, and the outer diameter and dimensions of the roller rolling surface meet the design requirements. This yields a finished roller that meets the required profile and dimensional accuracy. (See attached image.) Figure 6 .

[0058] By using ultra-precision grinding, the final surface quality of the rollers is improved and guaranteed, so that the roundness error and surface roughness of the roller outer diameter surface meet the G1 level.

[0059] Step 10: Magnetic particle inspection (MT); After the finished rollers are processed, a magnetic particle inspection machine is used to inspect for defects such as cracks on the surface and near the surface of the rollers, effectively detecting such defects. After passing the inspection, the rollers proceed to the cleaning process.

[0060] Step 11: Cleaning; An automatic roller cleaning machine with automatic loading and unloading function is used to clean the rollers after the previous ultra-precision grinding and MT processes. The automatic loading and unloading function can effectively reduce the manual labor intensity caused by high-frequency loading and unloading, ensure a high degree of roller surface cleanliness, and prepare for the subsequent ultrasonic treatment process.

[0061] Step 12, Ultrasonic Testing (UT); A water-immersion ultrasonic flaw detector is used to inspect the internal defects of the rollers, such as cracks and porosity. This method is effective in detecting internal defects like cracks and porosity. After passing the ultrasonic flaw detection, a visual inspection process is performed.

[0062] Step 13: Visual inspection; The appearance of the rollers is inspected using visual inspection under diffused light or by using an automated optical inspection device to ensure that there are no defects such as scratches, rust, or residual contaminants. The appearance quality of the rollers must meet the requirements of GB / T 4661-2015 Rolling Bearings - Cylindrical Rollers, GB / T 24608-2023 Inspection Rules for Rolling Bearings and Their Commercial Parts, and CSBTSTC98.54-1999 Appearance Quality Requirements for Rolling Bearing Parts - Rings and Rollers.

[0063] Step Fourteen: Grouping; An automatic roller grouping machine is used to group rollers that have passed the appearance inspection into batches, and rollers that do not meet the batch diameter variation value or the batch length variation value are rejected.

[0064] Step 15: Rust prevention; After drying, the rollers are coated with oil using an automatic oiling machine for rust prevention, which lasts for two years. The rust-preventive oil and other rust-preventive measures meet the requirements of GB / T 8597-2013 "Rust-preventive Packaging for Rolling Bearings," further ensuring the quality of the finished rollers.

[0065] Step Sixteen: Packaging; The rollers, after being coated with oil, should be packaged immediately. The inner packaging should use air-venting polyethylene plastic bags or plastic films, and the packaging method should meet the requirements of GB / T4879—2016 Rust-proof Packaging. The outer packaging should use double-walled cardboard boxes. Requirements for the packaging of the rollers should be established to ensure proper storage.

[0066] Step 17: Identification; The label is affixed to the double-walled cardboard box containing the rollers using self-adhesive labels. The label includes the name, nominal diameter, nominal length, tolerance grade, roller diameter / length specifications, production date, and batch number. This label clearly identifies the roller's parameters, facilitating management and traceability.

[0067] Example 2: This embodiment provides a roller, which is processed using the processing method described in Embodiment 1.

[0068] Example 3: This embodiment provides a tunneling machine main bearing, wherein the rollers of the tunneling machine main bearing are as described in Embodiment 2.

[0069] The above description is only a preferred embodiment of the present invention and does not limit the scope of protection of the present invention. All equivalent structural transformations made under the inventive concept of the present invention using the contents of the present invention specification and drawings, or direct / indirect applications in other related technical fields, are included within the scope of protection of the present invention.

Claims

1. A method for machining rollers for the main bearing of a tunneling machine, characterized in that, Includes the following steps: Step 1: Customize the bar stock; Step 2: Unloading materials; Cut the material according to the preset cutting length to obtain a blank blank for a single roller; Step 3, soft carriage; The blank part is then soft-turned to obtain a soft-turned roller part; Step 4: Heat treatment; The soft-turned roller parts were heat-treated by 880±5°C bainitic quenching process and then tempered at 220±5°C to obtain heat-treated roller parts with a surface hardness of not less than 59HRC. Step 5, Hardening; Hard turning of heat-treated roller parts includes: First, machine the first end face of the heat-treated roller part; Using the first machined end face as the reference surface, the machining length is 2 / 3. The rolling surface, after machining, has a radial dimension of... ; The chamfer at the first end is machined using a five-segment circular arc chamfering method; wherein: The length of the roller component after hard turning. The diameter of the roller component after hard turning; Flip the roller component over and clamp the machined rolling surface; machine the second end face of the roller component, resulting in a roller component length of [length to be specified]. ; The remaining rolling surface is machined, and the radial dimension after machining is: ; The chamfer at the second end is processed using a five-segment circular arc chamfering method; Obtain hard rolling mill rollers; Step 6: Rough grinding of the rolling surface; The rolling surface of the hardened roller is rough ground to obtain a rough-ground roller; Step 7: Grind both end faces thoroughly; A vertical double-sided grinding machine is used to grind the two end faces of the rough grinding roller to meet the length requirements of the finished roller. Step 8: Fine grinding of the rolling surface; The rollers after fine grinding of the double end faces are cleaned; the outer circle contour of the rollers is finely ground using a CNC cylindrical grinding machine to form a logarithmic curve contour, and the machining allowance after fine grinding is controlled within the range of 0.001~0.008mm. Step Nine, Ultra-precision Research; The rolling surface of the precision-ground roller is subjected to ultra-precision treatment to make the roller roundness ≤0.0003mm and the roughness Ra≤0.08μm, so as to obtain the finished roller that meets the profile accuracy and dimensional accuracy.

2. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, Customized bar stock is made of rolled round steel, and the material is any one of 100CrMo7-3, 100CrMo7-4, or 100CrMnMoSi 8-4-6; The diameter of the custom-made bar , This indicates the diameter of the finished roller; the allowable deviation for the diameter of custom-made bar stock is ±1mm. The length of the custom-made bar stock is 4000mm~6000mm; the out-of-roundness is ≤0.7mm; the curvature is ≤2.8mm / meter; and the total curvature is ≤15mm.

3. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, Customized bar stock is cut and blanked using a high-speed saw, with the saw blade speed set to ≥100 rpm / min; Preset cutting length , This indicates the length of the finished roller; the allowable deviation for the blanking dimension is ±1mm.

4. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, The blank workpiece is subjected to soft turning, including: First, machine the first end face of the blank; Using the first machined end face as the reference surface, the machining length is 2 / 3. The rolling surface, after machining, has a radial dimension of... ;in: The length of the flexible roller component. The diameter of the flexible roller component; Chamfering at the first end This yields semi-finished soft-roller parts; The semi-finished roller assembly is flipped over, and the rolled surface after machining is clamped. The second end face is then machined, resulting in a roller assembly with a length of [length missing]. ; The remaining rolling surface is machined, and the radial dimension after machining is: ; Chamfering at the second end ; The soft-roller component is obtained.

5. The method for machining rollers for the main bearing of a tunneling machine according to claim 4, characterized in that, The blank workpiece is machined using a high-precision CNC horizontal lathe, with ceramic cutting inserts and a tool radius of 0.4mm. Diameter of flexible rolling elements , Indicates the diameter of the finished roller; Length of soft-roller components , Indicates the length of the finished roller; Chamfering of soft-roller parts , The value range is 1 to 3. This refers to the chamfering dimensions of the finished roller.

6. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, The five-segment circular arc chamfering method is specifically as follows: In order , , , , The tool path for machining the rounded chamfer is completed in the following sequence; where: This refers to the toolpath trajectory of the lathe tool. Chamfering for roller parts after hard turning; For end face and The transition arc, With end face and Tangent; yes The transition arc between the rolling surface number curve profile of the finished roller; This refers to the retraction toolpath of the lathe tool. The profile of the rolling surface number curve of the finished roller and Tangent.

7. The method for machining rollers for the main bearing of a tunneling machine according to claim 6, characterized in that, and The point of tangency on the end face is tangency point one. and The point of tangency of the rolling surface number curve profile of the finished roller is point two, and the horizontal and vertical distances between point one and point two are both... , .

8. The method for machining rollers for the main bearing of a tunneling machine according to claim 7, characterized in that, and The value is 0.4 ~0.6 , and The value is 0.3 ~0.8 .

9. The method for machining rollers for the main bearing of a tunneling machine according to claim 6, characterized in that, During hard turning, the tool radius should be ≤0.8mm; Diameter of hard rolling mill rollers , Indicates the diameter of the finished roller. The value range is 0.25~0.5mm; Length of hard car rollers , Indicates the length of the finished roller. The value range is 0.15~0.3mm; chamfering of hard rollers , The value range is 1 to 3. This refers to the chamfering dimensions of the finished roller; The tool marks on the rolling surface of hard-machined rollers must be controlled to be ≤0.1mm.

10. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, The rolling surface of the hard-turned roller is rough-ground using a CNC centerless cylindrical grinder, wherein the rolling surface profile is taken from the middle. For straight lines, the rest follow the contour curve of the finished roller. Grinding is performed. The value range is 0.02~0.1mm; Indicates the effective length of the finished roller; Diameter of coarse grinding roller , Indicates the diameter of the finished roller. The value range is 0.1~0.15mm.

11. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, A vertical double-sided grinding machine is used to grind the two end faces of the rough grinding roller. CBN grinding wheels are selected for the upper and lower discs, and the upper and lower grinding wheels rotate in opposite directions to uniformly correct the flatness and parallelism of the roller end faces.

12. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, The outer diameter of the roller is precision ground using a CNC cylindrical grinding machine. The roller end face is limited by magnetic pole adsorption. Before processing, the surface of the magnetic pole tooling is ground by vertical positioning of the roller processing position to ensure that the vertical difference between the surface of the magnetic pole tooling of the roller of this specification and the base set parallel to the roller axis is ≤0.001mm.

13. The method for machining rollers for the main bearing of a tunneling machine according to claim 1, characterized in that, It also includes demagnetization; the rollers after fine grinding of the rolling surface are demagnetized to ensure that the residual magnetism is ≤0.3mT.

14. A roller, characterized in that, It is obtained by processing according to any one of claims 1-13.

15. A main bearing for a tunneling machine, characterized in that, The rollers of the main bearing of the tunneling machine are those described in claim 14.

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