Processing method of high-speed magnetic suspension integral track beam

Abstract

The invention relates to the technical field of high-speed magnetic suspension integral track beam machining, in particular to a machining method of a high-speed magnetic suspension integral track beam. In order to solve the problems that a traditional track beam machining method is poor in structural safety and the machining precision is insufficient to meet the dimensional precision requirement of a high-speed magnetic suspension integral track beam, the invention provides a novel machining method of the high-speed magnetic suspension integral track beam. Comprising the following steps that the integral track beam is formed in a pouring mode, machining is conducted on the track beam, and during machining, the machining method with the machining faces serving as the reference is adopted, so that the size precision control over the high-speed magnetic suspension integral track beam is guaranteed, the construction efficiency of the integral track beam is greatly improved, the construction progress is guaranteed, and the construction cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of processing of high - speed maglev integral track beams, and specifically to a processing method for high - speed maglev integral track beams. Background Art

[0002] With the continuous progress of society, people have higher and higher pursuits for the high - speed and comfort of transportation tools. According to the principle of "like poles repel, opposite poles attract", the high - speed maglev rail transit system, with technical features such as non - contact operation, vehicle hugging the rail, and ground synchronous traction, can better meet people's needs for higher speed, lower noise, and more comfortable and stable ride.

[0003] When processing traditional track beams, the construction structure form of "composite beam" is adopted, that is, the track beam is divided into a lower load - bearing beam and an upper track slab (the upper track slab is equipped with track functional components, and the track functional components are composed of a sliding plate, a guiding plate, socket bolts, a square socket with a dovetail groove, and a round socket without a dovetail groove), and they are prefabricated separately, and then combined together by means of a post - cast strip. However, during the long - term operation test process, cracks of varying degrees have occurred at the post - cast strip, affecting the structural safety. In addition, to ensure the safety of high - speed maglev vehicle operation and the comfort of passengers, the track beam size accuracy is required to be relatively high. Simply relying on reinforced concrete construction can no longer meet the design accuracy requirements. In the prior art, machining is also used to ensure the track beam size accuracy, but generally for traditional track beams. The traditional track beam is composed of track slabs with a unit length of 3.096m, and the one - time machining length of the track slab is only 3.096m. For a longer high - speed maglev integral track beam, such as its length reaching 12.384m, the corresponding machined track beam length is also 12.384m, and its numerical accuracy requirements for the geometric dimensions of the sliding surface, guiding surface, embedded socket, and the spacing between them are extremely high, all within 0.2mm to 0.6mm. During machining, extremely high accuracy requirements are put forward for the treatment of the initial machining surface, the selection of the reference point, the processing sequence of each part, and the control of the feed rate. The machining control is difficult, and the control accuracy of the existing track beam machining method is insufficient to meet the size accuracy requirements of high - speed maglev integral track beams. Summary of the Invention

[0004] In order to solve the problems of structural safety existing in the traditional track beam processing method and the processing accuracy being insufficient to meet the size accuracy requirements of high - speed maglev integral track beams, the present invention provides a new processing method for high - speed maglev integral track beams.

[0005] The present invention is realized by adopting the following technical solutions: A processing method for high - speed maglev integral track beams, comprising the following steps: 1) Integrally cast the upper track slab and the lower load-bearing beam to form a precast integral track beam. Among them, the upper track slab is equipped with track functional components, and a certain amount of machining allowance is reserved for the precast integral track beam; 2) Tension the integral track beam and let it stand for a period of time to eliminate the deformation caused by creep and temperature; 3) Lift and place the integral track beam onto a numerically controlled gantry milling machine for machining a. Level the beam surface and align the beam body of the integral track beam Use a total station for measurement. Place several steel plates under the four bottom corners of the integral track beam, and adjust the four corners of the sliding plate on the integral track beam to the same elevation to ensure the parallelism between the integral track beam and the horizontal milling cutter. Then, make the midpoints at both ends of the integral track beam coincide with the midpoints of the numerically controlled gantry milling machine bed body respectively to ensure the alignment of the beam body of the integral track beam. Finally, position and fix the integral track beam at the current position on the numerically controlled gantry milling machine; b. Machine the sliding plate Start milling the sliding surface of the sliding plate along the Z direction with a feed rate until the smoothness reaches the design requirements; c. Machine the bottom end of the guide plate Take the sliding surface completed in step b as the reference surface, flip the tool head by 180°, and start milling the bottom end of the guide plate along the Z direction until the distance between the machined bottom end of the guide plate and the sliding surface reaches the design requirements; d. Machine the stator mounting seat Take the bottom end of the guide plate completed in step c as the reference surface, and start milling the bottom surfaces of all sleeves along the Z direction multiple times until the total feed rate of the tool head in the Z direction reaches the design requirements; e. Machine the guiding surface of the guide plate Precisely center the integral track beam precast in the transverse direction of the bridge to obtain the thickness to be milled off on one side of the guiding surface. Start milling one side of the guiding surface along the X direction multiple times until the feed rate reaches the thickness value to be milled off and the smoothness of this side of the guiding surface reaches the design requirements. Then, take this side of the guiding surface as the reference surface, flip the tool head by 180°, and start milling the other side of the guiding surface along the X direction until the X-direction distance between the tool head and the machined guiding surface reaches the design requirements; f. Machine the dovetail groove Take one end face of the integral track beam in the Y direction as the reference surface in the Y direction, and take the machined stator mounting seat as the reference surface in the Z direction. Use a special dovetail groove tool head to mill the dovetail groove along the Y direction in sequence according to the design spacing and design dimensions of multiple dovetail grooves; g. Drill holes and thread After all the dovetail grooves are machined, once again, take one end face of the monolithic track beam in the Y direction as the reference plane in the Y direction, and take the machined stator mounting base as the reference plane in the Z direction. Then, use the drill bit for drilling and threading to drill holes along the Y direction in sequence according to the designed spacing and size of multiple holes. 4) Inspection, measurement and acceptance After machining is completed, check and measure the machining dimensional accuracy of each component according to the design requirements of the construction drawings. 5) Spraying for rust removal and painting After the monolithic track beam after machining is inspected, measured and accepted as qualified, use the gantry crane to lift and place the monolithic track beam to the sandblasting and rust removal site. Sandblast and remove rust strictly according to the roughness required by the drawing design, and then spray paint according to the painting process required by the design, thus completing the machining of the high-speed maglev monolithic track beam.

[0006] Furthermore, in step 3) a, the thickness of the steel plate spacer is 0.5 mm - 2 mm.

[0007] Furthermore, in step 3) a, the monolithic track beam is positioned and fixed by inserting wedge blocks into the slots of the CNC gantry milling machine bed at both ends of its track beam. The method is simple and practical.

[0008] Furthermore, in step 3) b, measure the smoothness of the sliding surface once using the percentage along the bridge to make a preliminary estimate of the unevenness, which is convenient for selecting the preliminary feed amount when milling the sliding surface.

[0009] Furthermore, in step 3), before lifting and placing the monolithic track beam onto the CNC gantry milling machine, it is necessary to measure the bed of the CNC gantry milling machine using a total station to ensure that the flatness is consistent and prevent adverse effects on the machining of the monolithic track beam.

[0010] The beneficial effects produced by the present invention are as follows: The processing method of the high-speed maglev monolithic track beam described in the present invention combines the traditional construction of precast concrete beams with machining. By means of monolithic casting, its structural safety is ensured, and by means of machining with mutual reference, the dimensional accuracy control of the high-speed maglev monolithic track beam is greatly ensured, the construction efficiency of the monolithic track beam is greatly improved, the construction progress is ensured, and the construction cost is reduced. BRIEF DESCRIPTION OF THE DRAWINGS

[0011] The drawings here are incorporated into the specification and form a part of this specification, showing the embodiments in line with the present invention, and are used together with the specification to explain the principles of the present invention.

[0012] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings required in the description of the embodiments or the prior art. Obviously, for those of ordinary skill in the art, without creative efforts, other drawings can also be obtained based on these drawings.

[0013] Figure 1 The front view of the integral track beam of the high-speed maglev described in the present invention; Figure 2 is Figure 1 the side view of; Figure 3 The flowchart for machining the integral track beam; Figure 4 The positioning schematic diagram of the integral track beam; Figure 5 The machining schematic diagram of the sliding surface and the bottom end of the guide plate; Figure 6 The machining schematic diagram of the stator mounting seat; Figure 7 The machining schematic diagram of the guide surface; Figure 8 The machining schematic diagram of the dovetail groove and hole threading.

[0014] In the figure: 1 - integral track beam, 2 - sliding plate, 3 - guide plate, 4 - sleeve, 5 - tool bit, 6 - dovetail groove, 7 - hole, 8 - CNC gantry milling machine. Detailed implementation manners

[0015] In order to more clearly understand the above-mentioned objects, features, and advantages of the present invention, the following will further describe the solutions of the present invention. It should be noted that, without conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other.

[0016] In the description, it should be noted that the terms "first" and "second" are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. It should be noted that unless otherwise clearly defined and limited, the terms "installation", "connection", and "coupling" should be understood in a broad sense. For example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection, an electrical connection; it can be directly connected, or indirectly connected through an intermediate medium, and it can be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms can be understood according to specific situations.

[0017] In the following description, numerous specific details are set forth to provide a thorough understanding of the present invention. However, the present invention may be practiced in other ways different from those described herein. Obviously, the embodiments in the specification are only a part of the embodiments of the present invention, rather than all of the embodiments.

[0018] The following specifically describes the embodiments of the present invention with reference to the accompanying drawings.

[0019] The following takes the Qingdao high-speed maglev commissioning platform project as an example for detailed description.

[0020] The integral track beam of high-speed maglev is a hollow "π" - shaped structure. The main dimensions are: beam length 6172 mm or 12364 mm, beam height 1500 mm, beam top width 2100 mm, beam bottom width 2200 mm, and web thickness 660 mm.

[0021] The key point in the construction of the integral track beam of high - speed maglev lies in the control of precision. Different from the construction of ordinary precast beams in the past, the precision of the main structural dimensions of the beam body precast this time must be controlled within 1 mm, and individual dimensions must be controlled within 0.5 mm.

[0022] As Figure 1 、 2 、as shown in Figure 3, the processing method of the integral track beam of high - speed maglev includes the following steps: 1) Integrally pour the upper track slab and the lower load - bearing beam into one body to form a precast integral track beam 1. Among them, the upper track slab is equipped with track functional components, and a certain amount of machining allowance is left for the precast integral track beam 1; 2) Tension the integral track beam 1 and let it stand for 40 days to eliminate the creep and temperature - induced deformation; 3) Lift and place the integral track beam 1 onto the CNC gantry milling machine 8 for machining. Before lifting and placing, it is necessary to use a total station to measure the bed of the CNC gantry milling machine 8 to ensure the flatness is consistent, so as to prevent adverse effects on the machining of the integral track beam 1; The specific steps of machining are as follows: a. Level the beam surface and align the beam body of the integral track beam 1 As Figure 4 shown, use a total station for measurement. Place several steel plates with a thickness of 0.5 mm - 2 mm under the four bottom corners of the integral track beam 1 to adjust the four corners (points A, B, C, and D) of the sliding plate 2 on the integral track beam 1 to the same elevation, so as to ensure the parallelism between the integral track beam 1 and the horizontal milling cutter. Then, make the mid - points (points D and F) at both ends of the integral track beam 1 coincide with the mid - points (point E) of the bed of the CNC gantry milling machine 8 respectively to ensure the alignment of the beam body of the integral track beam 1. Finally, fix the integral track beam 1 in its current position on the CNC gantry milling machine 8 through wedge - shaped blocks for positioning; b. Machining the sliding plate 2 As Figure 5 shown, use the percentage along the bridge to measure the smoothness of the sliding surface once, make a preliminary estimate of the unevenness, which is convenient for selecting the preliminary feed rate when milling the sliding surface, and then start milling the sliding surface of the sliding plate 2 along the Z direction with a feed rate of 0.5 mm until the smoothness reaches 1 / 1000 mm; c. Machining the bottom end of the guide plate 3 As Figure 5 shown, take the sliding surface completed in step b as the reference surface, flip the tool bit 5 by 180°, and start milling the bottom end of the guide plate 3 along the Z direction until the distance between the bottom end of the machined guide plate 3 and the sliding surface reaches the designed dimension of 330 mm; d. Machining the stator mounting seat As Figure 6 shown, the design requires that the height of the stator mounting seat should be 57.5 mm higher than the bottom end of the guide plate 3. During machining, take the bottom end of the guide plate 3 completed in step c as the reference surface, and start milling the bottom surfaces of all sleeves 4 along the Z direction multiple times until the total feed rate of the tool bit 5 in the Z direction reaches 57.5 mm, that is, meeting the design requirements; e. Machining the guiding surface of the guide plate 3 Precisely center the integral track beam 1 precast in the transverse direction of the bridge, and obtain the thickness to be milled off on one side of the guiding surface (as Figure 7 shown, after centering, it can be known that the width on one side is 1055 mm, so 5 mm needs to be milled off). Start milling one side of the guiding surface along the X direction multiple times with a feed rate of 0.5 mm until the feed rate reaches the thickness value to be milled off and the smoothness of this side of the guiding surface meets the design requirements. Then, take this side of the guiding surface as the reference surface, flip the tool bit 5 by 180°, and start milling the other side of the guiding surface along the X direction until the X - direction distance between the tool bit 5 and the machined guiding surface reaches 2100 mm to meet the design requirements; f. Machining the dovetail groove 6 Take one end face of the integral track beam 1 in the Y direction as the reference surface in the Y direction, and the machined stator mounting seat as the reference surface in the Z direction. Use the special tool bit 5 for the dovetail groove 6 to mill the dovetail groove 6 along the Y direction according to the designed spacing of multiple dovetail grooves 6 (as Figure 8 shown, for the first dovetail groove 6 at the beam end, the tool bit 5 needs to move 162 mm along the Y direction) and the designed dimensions in sequence; g. Drilling and threading After all the dovetail grooves 6 are machined, once again take one end face of the integral track beam 1 in the Y direction as the reference surface in the Y direction, and the machined stator mounting seat as the reference surface in the Z direction. Use the drill bit for drilling and threading to drill the holes 7 along the Y direction according to the designed spacing and designed dimensions of multiple holes 7 in sequence; 4) Inspection, measurement and acceptance After machining is completed, check and measure the machining dimensional accuracy of each component according to the design requirements of the construction drawings; ① Length and width of the track beam: The length and width of the track beam are 12384 mm and 2100 mm respectively, referring to the starting and ending point distances of the edges of the sliding plate 2 and the guiding plate 3 at the top of the beam. Mainly use a high-precision steel tape measure and measure strictly according to the standard tension of 20 N. The qualified standard is ±1 mm; ② Irregularity of the sliding surface and guiding surface: This strictly requires the flatness of the sliding surface and guiding surface. Mainly use a flatness measuring instrument composed of a dial indicator and a slide rail, as well as a knife ruler and a feeler gauge for measurement. The qualified standard is 3 / 1000 mm; ③ Longitudinal and transverse bridge spacing of the stator mounting seat: The design values are required to be 344 mm and 240 mm respectively. Mainly use a taper probe vernier caliper dedicated to measuring the center distance for measurement. The qualified standard is ±0.1 mm; ④ Clamp span distance: It refers to the distance between the sliding surface and the stator mounting surface. The design value is required to be 272.5 mm. Mainly use a square for measurement. The qualified standard is +3 / -5 mm within the beam span and ±0.6 mm at the beam end; ⑤ Rail gap width: It refers to the gap between adjacent track units within the beam span. The design value is required to be 2 mm. Mainly use a feeler gauge for measurement. The qualified standard is ±1 mm on the premise of ensuring the qualified beam length; ⑥ Thickness of the guiding surface and thickness of the sliding surface: The design values are required to be 30 mm and 15 mm respectively. Mainly use a vernier caliper for measurement. The qualified standard is ±0.5 mm; ⑦ Height of the guiding surface and width of the sliding surface: The design values are required to be 330 mm and 435 mm respectively. Mainly use a vernier caliper for measurement. The qualified standard is ±0.5 mm; 5) Spray rust removal and painting After the integral track beam 1 after machining is inspected and measured and accepted as qualified, use a gantry crane to lift and place the integral track beam 1 to the sandblasting and rust removal site, and perform sandblasting and rust removal strictly according to the roughness required by the drawing design, and then spray paint according to the paint coating process required by the design, thus completing the machining of the high-speed maglev integral track beam 1.

[0023] It has been verified that the dimensional accuracy of the integral track beam 1 processed by this construction method meets the machining accuracy of the high-speed maglev integral track beam 1, and this machining method is feasible.

[0024] The above are only specific embodiments of the present invention, enabling those skilled in the art to understand or implement the present invention. Although the foregoing embodiments have been described in detail, those of ordinary skill in the art should understand that they can still modify the technical solutions described in the foregoing embodiments, or perform equivalent replacements on some or all of the technical features; and these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the respective embodiments, and they should all be covered by the protection scope of the claims.

Claims

1. A method for processing a high-speed magnetic suspension integral track beam, characterized in that: The following steps are included 1) The upper track plate and the lower load-bearing beam are integrally cast to form a prefabricated integral track beam (1), wherein the upper track plate is provided with track functional parts, and the prefabricated integral track beam (1) has a certain amount of machining left; 2) The integral track beam (1) is tensioned and left to stand for a period of time to eliminate deformation caused by creep and temperature; 3) The integral track beam (1) is hoisted onto a CNC gantry milling machine (8) for machining. a. Leveling the beam surface and adjusting the beam body of the integral track beam (1) A total station is used to measure, and several steel plates are placed on the four bottom corners of the integral track beam (1). The four corners of the sliding plate (2) on the integral track beam (1) are adjusted to the same elevation to ensure that the integral track beam (1) is parallel to the horizontal milling cutter. The midpoints of both ends of the integral track beam (1) are respectively aligned with the midpoints of the bed of the CNC gantry milling machine (8) to ensure that the beam of the integral track beam (1) is adjusted correctly. Finally, the integral track beam (1) is positioned and fixed at the current position on the CNC gantry milling machine (8); b. Processing of sliding plates (2) Milling the sliding surface of the sliding plate (2) along the Z direction with a feed amount until the smoothness required by the design is achieved; c. Process the bottom end of the guide plate (3) Using the sliding surface processed in step b as the reference surface, the cutter head (5) is turned 180 degrees and the bottom end of the guide plate (3) is milled along the Z direction until the distance between the bottom end of the guide plate (3) and the sliding surface reaches the design requirement; d. Processing stator mounting seat Taking the bottom end of the guide plate (3) processed in step c as the reference plane, mill the bottom surfaces of all sleeves (4) multiple times along the Z direction until the total feed amount of the cutter head (5) in the Z direction reaches the design requirement; e. Processing the guide surface of the guide plate (3) The prefabricated integral rail beam (1) is precisely divided in the transverse direction to obtain the thickness of the guide surface on one side that needs to be milled, and the guide surface on one side is milled multiple times along the X direction until the feed amount reaches the thickness value to be milled and the smoothness of the guide surface on this side meets the design requirements, and then the guide surface on this side is used as a reference surface, the cutter head (5) is turned 180 degrees, and the guide surface on the other side is milled multiple times along the X direction until the X-direction distance between the cutter head (5) and the processed guide surface meets the design requirements; f. Processing dovetail groove (6) Using one end surface of the integral track beam (1) in the Y direction as a reference surface in the Y direction and the machined stator mounting seat as a reference surface in the Z direction, a dovetail groove (6) is sequentially milled along the Y direction according to the designed spacing and designed dimensions of the plurality of dovetail grooves (6) using a dovetail groove (6) special cutter head (5); g. Opening and threading After all dovetail grooves (6) are processed, one end surface of the integral track beam (1) in the Y direction is used as the reference surface in the Y direction, and the processed stator mounting seat is used as the reference surface in the Z direction. The drill used for drilling and threading is used to drill holes (7) in sequence along the Y direction according to the designed spacing and designed size of the multiple holes (7); 4) Inspection, measurement and acceptance After machining is completed, the machining dimensional accuracy of each component is inspected and measured according to the design requirements of the construction drawings; 5) Spraying rust removal and painting After the machined integral track beam (1) is inspected and measured and accepted, the integral track beam (1) is hoisted to a sandblasting and rust removal site using a gantry crane, and sandblasted and rust removed in strict accordance with the roughness required by the design drawing, and then painted in accordance with the paint coating process required by the design, thereby completing the processing of the high-speed magnetic suspension integral track beam (1).

2. The method for processing a high-speed magnetic suspension integral track beam (1) according to claim 1, characterized in that: In step 3) a, the thickness of the steel plate spacer is 0.5mm-2mm.

3. The method for processing a high-speed magnetic suspension integral track beam (1) according to claim 2, characterized in that: In step 3) a, the integral track beam (1) is positioned and fixed by inserting wedge blocks at both ends of the track beam into the grooves of the bed of the CNC gantry milling machine (8).

4. The method for processing a high-speed magnetic suspension integral track beam (1) according to claim 3, characterized in that: In step 3) b, use the percentage straight line to measure the smoothness of the sliding surface, so as to have a preliminary estimate of the unevenness, so as to facilitate the selection of the initial feed amount when milling the sliding surface.

5. The method for processing a high-speed magnetic suspension integral track beam (1) according to claim 4, characterized in that: In step 3), before the integral track beam (1) is hoisted onto the CNC gantry milling machine (8), the bed of the CNC gantry milling machine (8) is measured using a total station to ensure that the bed of the CNC gantry milling machine (8) is uniformly flat.

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