Telescoping sleeve of loading and unloading machine, and machining method

Abstract

A telescoping sleeve of a loading and unloading machine, and a machining method therefor. The machining method comprises: first carrying out rough machining on an upper flange (1), a lower flange (2), guide rails (3), mounting supports (4), and a sleeve tube (5); welding two rows of mounting supports (4) on two opposite sides of the sleeve tube (5) having small straightness; using a numerical-control plane milling and boring machine to align and machine the top surfaces and recessed straight slots (4-1) of the mounting supports (4); respectively welding the two guide rails (3) in two rows of recessed straight slots (4-1); respectively fitting the upper flange (1) and the lower flange (2) into outer stop openings of two ends of the sleeve tube (5), and carrying out positioning, assembling and welding; and finally, carrying out integral finish machining, so as to complete the machining of the telescoping sleeve of the loading and unloading machine. The straightness, symmetry, flatness and the like of the telescoping sleeve of the loading and unloading machine meet the requirements, the precision tolerance requirements of design drawings are ensured, and the requirements for functionality in apparatus debugging are satisfied.

Description

Telescopic sleeve of loading and unloading machine and processing method thereof Technical Field

[0001] The invention belongs to the technical field of pressurized water reactor nuclear power plant related equipment, and particularly relates to a telescopic sleeve of a loader and unloader and a processing method thereof. Background Art

[0002] The primary function of a fuel loader and unloader at a pressurized water reactor nuclear power plant is loading and unloading fuel assemblies. Its safety and stability are directly linked to the safety and efficiency of the power plant. Fuel loading and unloading is also a critical part of an overhaul, requiring the equipment to be in excellent condition. The loader and unloader's core component, the telescopic sleeve, is 8.7 meters long and weighs approximately 620 kg. Its lower end houses the fuel assembly gripper, while its upper end is connected to two wire ropes via a suspension head. During normal operation, the telescopic sleeve rises and falls by retracting and extending the wire ropes. When the loader and unloader is shut down, the telescopic sleeve hangs vertically within the fixed sleeve. Because the telescopic sleeve is suspended solely by the main lifting mechanism's wire ropes, with no other mechanical support structure, the loader and unloader's ultimate performance and relevant technical indicators are determined by the telescopic sleeve's smooth upward and downward movement, carrying the gripper to grasp and release the fuel assemblies. Therefore, the machining precision of the telescopic sleeve is paramount.

[0003] The telescopic sleeve is welded from a long, thin-walled stainless steel tube and other smaller stainless steel parts. The rails on either side of the tube serve as guides for capturing and releasing the fuel assembly core, resulting in extremely high machining precision (rail straightness 0.25mm, symmetry 0.03mm, parallelism 0.06mm). However, due to the poor rigidity and easy deformation of these thin-walled, long, stainless steel rod-like welded components, the straightness, symmetry, and flatness of the telescopic sleeve rails often fail to meet requirements. Therefore, overall machining technology has long been a challenge in the machining industry.

[0004] Summary of the Invention

[0005] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a telescopic sleeve for a loader and a processing method thereof, so as to solve the technical difficulties in the overall manufacturing and processing of the existing thin-walled stainless steel slender rod-shaped welded component - the telescopic sleeve for a loader and an unloader.

[0006] In order to solve the technical problem, the technical solution of the present invention is: a processing method of a telescopic sleeve of a loading and unloading machine, comprising the following steps:

[0007] Step 1: Rough machining of the upper flange, lower flange, guide rail, mounting support and sleeve tube, where there are two guide rails and multiple mounting supports;

[0008] Step 2: Recheck the straightness and roundness of the sleeve tube, and use the two opposite directions with smaller straightness of the sleeve tube as the welding orientations for the mounting bracket;

[0009] Step 3: Using the end face of one side of the sleeve tube as a reference, draw the positioning dimension line of the mounting bracket on the outer wall of the sleeve tube corresponding to the welding position. Use multiple gantry clamps to fix the sleeve tube on the construction platform, and weld the mounting bracket to the sleeve tube to form two opposite rows of mounting brackets.

[0010] Step 4: Align and machine the top surfaces of the two rows of mounting supports and the concave straight grooves on a CNC gantry boring and milling machine, ensuring that the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are in the same plane along the entire length direction, and that the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are symmetrical with respect to the center line of the sleeve tube;

[0011] Step 5: Place the lower end of the guide rail in the concave straight groove, adjust the reference position of the guide rail in the length direction, and weld the guide rail to the mounting bracket;

[0012] Step 6: Align the two end faces of the guide rail on the CNC gantry boring and milling machine and take the length. Determine the total length of the sleeve tube at both ends based on the end face of the guide rail, and process the outer stoppers at both ends of the sleeve tube to ensure that the outer stopper circles at both ends are concentric.

[0013] Step 7: Insert the upper flange and the lower flange into the outer ends of the sleeve tube respectively, and weld them in position;

[0014] Step 8: Use CNC gantry boring and milling machine to clamp and align in sequence, perform overall precision machining, and complete the machining of the telescopic sleeve of the loader and unloader.

[0015] Preferably, the rough processing process of the upper flange and the lower flange in step 1 is: processing the upper flange and the lower flange into a special-shaped structure with a cross-section of a square outer frame and a central inner circular hole, and processing the inner stop of the upper flange and the lower flange to match the sleeve tube, the thickness of the upper flange and the lower flange, the outer frame and the central inner hole are all left for post-weld processing, and all connecting threaded holes are processed after the upper flange and the lower flange are welded to the sleeve tube;

[0016] The rough machining process of the guide rail is as follows: the guide rail is processed into a long strip structure with a rectangular cross section, the lower end of the guide rail is processed into a stopper type, the lower end of the guide rail is placed in a concave straight groove for welding, the top surface and both side surfaces of the guide rail are left with post-weld processing allowance, the length of the guide rail is left with welding shrinkage and post-weld processing allowance, and the straightness of the entire length is within 0.5mm;

[0017] The rough machining process of the mounting bracket is as follows: the multiple mounting brackets are all machined into a square structure with a top surface and two side surfaces being flat and a bottom surface being an arc surface, the arc surface being adapted to the outer wall of the sleeve tube, the top surface of the mounting bracket is left with a post-weld machining allowance, and the concave straight groove corresponding to the mounting bracket is not machined at this time;

[0018] The rough processing process of the sleeve tube is as follows: welding shrinkage and post-weld processing allowance are left in the length direction of the sleeve tube, and the straightness of the entire length of the sleeve tube is controlled within 1.5mm.

[0019] Preferably, in step 2, the two end faces of the sleeve tube also need to be aligned, the two end faces are concentrically processed, and the two end faces are flush when exposed to light to ensure that the two end faces are perpendicular to the center of the sleeve tube.

[0020] Preferably, step 3 is specifically as follows: taking the end face of one side of the sleeve tube as a reference, drawing the positioning dimension line of the mounting support on the outer wall of the sleeve tube corresponding to the assembly welding orientation, accurately assembling and spot welding, and verifying that all dimensions are correct before welding the mounting support and the sleeve tube to form two opposite rows of mounting supports. During the welding process, the sleeve tube is placed on the construction platform along the length direction of the construction platform, and multiple gantry splints are used to fix the sleeve tube rigidly on the construction platform.

[0021] Preferably, the gantry splint fixing tooling includes an upper splint, a lower splint and two screws, through holes are provided on both sides of the upper splint, the upper end of the upper splint is a plane, the lower end of the upper splint is a circular arc surface, the circular arc surface is adapted to the outer wall of the sleeve tube, the lower end of the lower splint is a plane, the upper end of the lower splint is a circular arc surface, the circular arc surface is adapted to the outer wall of the sleeve tube, the upper end face of the construction platform is a plane, and a plurality of sliding grooves are provided on the upper end face of the construction platform along the length direction, the large diameter ends of the two screws are limited in the sliding grooves and can slide along the sliding grooves, the small diameter ends of the two screws pass through the through holes on both sides of the upper splint and are connected with nuts, and multiple gantry splint fixing tooling are evenly distributed at multiple points along the entire length of the sleeve tube to compress the sleeve tube, so that the sleeve tube is rigidly fixed on the construction platform to prevent the sleeve tube body from deformation due to welding heat input.

[0022] Preferably, the welding process of the guide rail and the mounting support in step 5 is as follows: the sleeve tube is placed on the construction platform along the length direction of the construction platform, and when welding the upper guide rail, the lower side of the lower mounting support is pressed against the construction platform, and a gantry plywood fixing tool is used to evenly distribute the sleeve tube at multiple points along the entire length for compression. After the upper guide rail is welded, the lower mounting support is turned over to become the upper mounting support. When welding the lower guide rail, the original upper guide rail top surface is pressed against the construction platform, and at the same time, a gantry plywood fixing tool is used to evenly distribute the sleeve tube at multiple points along the entire length for compression, so that the sleeve tube is rigidly fixed on the construction platform to prevent the guide rail from local warping and deformation, thereby completing the welding of the lower guide rail.

[0023] Preferably, step 7 is to respectively insert the inner stop of the upper flange and the lower flange into the outer stop at both ends of the sleeve tube, and position and weld them. During the welding process, the stainless steel tooling back plate is spot welded on the outer end faces of the upper flange and the lower flange for tensioning, so as to reduce the inner deformation of the upper flange or the lower flange caused by welding stress.

[0024] Preferably, all welds are subjected to surface non-destructive testing during steps 3 to 7, and all welds are polished after passing the test.

[0025] Preferably, the overall precision machining in step 8 is sequentially flipping back and forth, small cutting amount, and multi-pass symmetrical machining, interspersed with natural aging process.

[0026] Preferably, a telescopic sleeve of a loading and unloading machine is processed by the processing method of a telescopic sleeve of a loading and unloading machine described in any of the above items, and the telescopic sleeve of the loading and unloading machine includes an upper flange, a lower flange, a guide rail, a mounting support and a sleeve tube, wherein there are two guide rails and multiple mounting supports, the upper flange and the lower flange are respectively welded to the two end surfaces of the sleeve tube, and the multiple mounting supports are divided into two rows, and the two rows of mounting supports are respectively welded to two opposite directions of the sleeve tube with smaller straightness, and the top surface of each row of mounting supports and the groove surface of the concave straight groove are respectively in the same plane in the full length direction of the sleeve tube, and the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are symmetrical with respect to the center line of the sleeve tube, and the two guide rails are respectively welded in the concave straight grooves of the two rows of mounting supports.

[0027] Compared with the prior art, the advantages of the present invention are:

[0028] (1) The present invention discloses a processing method for a telescopic sleeve of a loading and unloading machine, which comprises the following steps: firstly, the upper flange, the lower flange, the guide rail, the mounting support and the sleeve tube are rough-machined, and then two rows of mounting supports are welded on two opposite sides of the sleeve tube where the straightness is smaller, and then a CNC gantry boring and milling machine is used to align and process the concave straight grooves, and then the two guide rails are welded into the two rows of concave straight grooves respectively, and then the upper flange and the lower flange are respectively inserted into the outer stoppers at both ends of the sleeve tube, and the positioning and welding are performed, and finally the whole is precision-machined to complete the processing of the telescopic sleeve of the loading and unloading machine. The straightness, symmetry and flatness of the telescopic sleeve processed by the processing method of the present invention meet the requirements, thereby ensuring the precision tolerance requirements of the design drawings and meeting the functional requirements of the equipment commissioning;

[0029] (2) The present invention uses two opposite directions of the sleeve tube with smaller straightness as the group welding orientations of the mounting supports, draws the positioning dimension lines of the mounting supports on the outer wall of the sleeve tube corresponding to the group welding orientations, uses multiple gantry clamps to fix the sleeve tube on the construction platform, and performs welding work on the mounting supports and the sleeve tube to form two opposite rows of mounting supports, which effectively improves the straightness;

[0030] (3) The present invention welds the mounting supports to the sleeve tube before aligning and processing the top surfaces and concave straight grooves of the two rows of mounting supports on a CNC gantry boring and milling machine, ensuring that the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are respectively in the same plane in the full length direction, and the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are symmetrical with respect to the center line of the sleeve tube, thereby ensuring symmetry and flatness to the greatest extent;

[0031] (4) The present invention adopts a gantry clamp fixing tool uniformly distributed at multiple points along the entire length of the sleeve tube for compression, so that it is rigidly fixed on the construction platform, preventing the sleeve tube body from being deformed due to welding heat input, and improving the straightness;

[0032] (5) The present invention adopts gantry clamps to fix the tooling evenly distributed at multiple points along the entire length of the guide rail and the sleeve tube for compression, so that the guide rail is rigidly fixed on the construction platform, thereby preventing the guide rail from being locally warped and deformed, and improving the symmetry and flatness. BRIEF DESCRIPTION OF THE DRAWINGS

[0033] FIG1 is a schematic structural diagram of a telescopic sleeve of a loading and unloading machine according to the present invention;

[0034] FIG2 is a cross-sectional view taken along line AA of FIG1 ;

[0035] FIG3 is a view taken along the line B of FIG1 ;

[0036] FIG4 is a C-direction view of FIG1 ;

[0037] FIG5 is a schematic diagram of the mounting support structure of a telescopic sleeve of a loading and unloading machine according to the present invention;

[0038] FIG6 is a schematic diagram of the processing process of a telescopic sleeve of a loading and unloading machine according to the present invention.

[0039] Explanation of the accompanying reference numerals: 1. Upper flange, 2. Lower flange, 3. Guide rail, 4. Mounting support, 5. Sleeve tube, 6. Construction platform, 7. Gantry splint fixing fixture; 4-1. Concave straight groove; 6-1. Slide groove; 7-1. Upper splint, 7-2. Lower splint, 7-3. Screw. DETAILED DESCRIPTION

[0040] The specific implementation of the present invention is described below in conjunction with examples:

[0041] It should be noted that the structures, proportions, sizes, etc. shown in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the conditions under which the present invention can be implemented. Any structural modification, change in proportional relationship or adjustment of size should still fall within the scope of the technical content disclosed in the present invention without affecting the efficacy and purpose that can be achieved by the present invention.

[0042] In addition, the accompanying drawings are merely schematic illustrations of embodiments of the present invention and are not necessarily drawn to scale. Identical reference numerals in the figures denote identical or similar parts, and thus repeated descriptions thereof will be omitted. Some of the structural diagrams shown in the accompanying drawings are functional entities and do not necessarily correspond to physically or logically independent entities.

[0043] Example 1

[0044] As shown in Figures 1 and 6, the present invention discloses a method for processing a telescopic sleeve of a loading and unloading machine, comprising the following steps:

[0045] Step 1: Roughly process the upper flange 1, the lower flange 2, the guide rail 3, the mounting support 4 and the sleeve tube 5, wherein there are two guide rails 3 and multiple mounting supports 4;

[0046] Step 2: Recheck the straightness and roundness of the sleeve tube 5, and use the two opposite directions of the sleeve tube 5 with smaller straightness as the assembly welding orientations for the mounting bracket 4;

[0047] Step 3: Using the end face of one side of the sleeve tube 5 as a reference, draw the positioning dimension line of the mounting bracket 4 on the outer wall of the sleeve tube 5 corresponding to the welding position, use multiple gantry clamps 7 to fix the sleeve tube 5 on the construction platform 6, and weld the mounting bracket 4 and the sleeve tube 5 to form two opposite rows of mounting brackets 4;

[0048] Step 4: Align and process the top surfaces of the two rows of mounting supports 4 and the concave straight grooves 4-1 on a CNC gantry boring and milling machine, ensuring that the top surfaces of the two rows of mounting supports 4 and the groove surfaces of the concave straight grooves 4-1 are respectively in the same plane in the full length direction, and the top surfaces of the two rows of mounting supports 4 and the groove surfaces of the concave straight grooves 4-1 are symmetrical with respect to the center line of the sleeve tube 5;

[0049] Step 5: Place the lower end of the guide rail 3 in the concave straight groove 4-1, adjust the reference position of the guide rail 3 in the length direction, and weld the guide rail 3 to the mounting bracket 4;

[0050] Step 6: Align and machine the two end faces of the guide rail 3 on a CNC gantry boring and milling machine and take the length. Determine the total length of the two ends of the sleeve tube 5 based on the end faces of the guide rail 3, and machine the outer stoppers at both ends of the sleeve tube 5 to ensure that the outer stopper circles at both ends are concentric.

[0051] Step 7: Insert the upper flange 1 and the lower flange 2 into the outer ends of the sleeve tube 5 respectively, and weld them in position;

[0052] Step 8: Use CNC gantry boring and milling machine to clamp and align in sequence, perform overall precision machining, and complete the machining of the telescopic sleeve of the loader and unloader.

[0053] Example 2

[0054] As shown in Figure 6, preferably, the rough processing process of the upper flange 1 and the lower flange 2 in step 1 is: the upper flange 1 and the lower flange 2 are processed into a special-shaped structure with a cross-section of a square outer frame and a central inner circular hole, and the inner stop of the upper flange 1 and the lower flange 2 that cooperates with the sleeve tube 5 is processed, and the thickness, outer frame and central inner hole of the upper flange 1 and the lower flange 2 are left with a post-weld processing allowance, and all connecting threaded holes are processed after the upper flange 1 and the lower flange 2 are welded to the sleeve tube 5;

[0055] The rough machining process of the guide rail 3 is as follows: the guide rail 3 is processed into a long strip structure with a rectangular cross section, the lower end of the guide rail 3 is processed into a stopper type, the lower end of the guide rail 3 is placed in the concave straight groove 4-1 for welding, the top surface and both side surfaces of the guide rail 3 are left with post-weld processing allowance, the length of the guide rail 3 is left with welding shrinkage and post-weld processing allowance, and the straightness of the entire length is within 0.5mm;

[0056] The rough machining process of the mounting bracket 4 is as follows: the multiple mounting brackets 4 are all machined into a square structure with a flat top surface and two side surfaces and a circular arc bottom surface. The circular arc surface is adapted to the outer wall of the sleeve tube 5. The top surface of the mounting bracket 4 is left with a post-weld machining allowance, and the concave straight groove 4-1 corresponding to the mounting bracket 4 is not machined at this time.

[0057] The rough machining process of the sleeve tube 5 is as follows: welding shrinkage and post-weld machining allowance are left in the length direction of the sleeve tube 5, and the straightness of the entire length of the sleeve tube 5 is controlled within 1.5 mm.

[0058] Example 3

[0059] As shown in FIG6 , preferably, in step 2 , the two end faces of the sleeve tube 5 also need to be aligned, and the two end faces are concentrically processed and flush with the light to ensure that the two end faces are perpendicular to the center of the sleeve tube 5 .

[0060] As shown in Figure 6, preferably, the step 3 is specifically as follows: taking the end face of one side of the sleeve tube 5 as a reference, drawing the positioning dimension line of the mounting support 4 on the outer wall of the sleeve tube 5 corresponding to the assembly welding orientation, accurately assembling and spot welding, and verifying that all dimensions are correct, then welding the mounting support 4 and the sleeve tube 5 to form two opposite rows of mounting supports 4. During the welding process, the sleeve tube 5 is placed on the construction platform 6 along the length direction of the construction platform 6, and a plurality of gantry splint fixing tools 7 are used to rigidly fix the sleeve tube 5 on the construction platform 6.

[0061] Example 4

[0062] As shown in Figure 6, preferably, the gantry plywood fixing tool 7 includes an upper plywood 7-1, a lower plywood 7-2 and two screws 7-3. Through holes are opened on both sides of the upper plywood 7-1. The upper end of the upper plywood 7-1 is a plane, and the lower end of the upper plywood 7-1 is a circular arc surface, which is adapted to the outer wall of the sleeve tube 5. The lower end of the lower plywood 7-2 is a plane, and the upper end of the lower plywood 7-2 is a circular arc surface, which is adapted to the outer wall of the sleeve tube 5. The upper end surface of the construction platform 6 is a plane, and the construction The upper end surface of the working platform 6 is provided with a plurality of slide grooves 6-1 along the length direction. The large diameter ends of the two screw rods 7-3 are limited to be located in the slide groove 6-1 and can slide along the slide groove 6-1. The small diameter ends of the two screw rods 7-3 pass through the through holes on both sides of the upper splint 7-1 and are connected with nuts. A plurality of gantry splint fixing fixtures 7 are evenly distributed at multiple points along the entire length of the sleeve tube 5 to compress the sleeve tube 5 so that the sleeve tube 5 is rigidly fixed on the construction platform 6 to prevent the sleeve tube 5 from being deformed due to the heat input of welding.

[0063] Example 5

[0064] As shown in Figure 6, preferably, the welding process of the guide rail 3 and the mounting support 4 in step 5 is: place the sleeve tube 5 on the construction platform 6 along the length direction of the construction platform 6, and when welding the upper guide rail 3, the lower side of the mounting support 4 is firmly attached to the construction platform 6, and a gantry plywood fixing tool 7 is evenly distributed at multiple points along the entire length of the sleeve tube 5 for compression. After the upper guide rail 3 is welded, the lower mounting support 4 is turned over to become the upper mounting support 4. When welding the lower guide rail 3, the original top surface of the upper guide rail 3 is firmly attached to the construction platform 6, and a gantry plywood fixing tool 7 is evenly distributed at multiple points along the entire length of the sleeve tube 5 for compression, so that the sleeve tube 5 is rigidly fixed on the construction platform 6 to prevent the guide rail 3 from local warping and deformation, and complete the welding of the lower guide rail 3.

[0065] As shown in Figure 6, preferably, step 7 is to respectively insert the inner ends of the upper flange 1 and the lower flange 2 into the outer ends of the sleeve tube 5, position and weld them, and spot weld the stainless steel tooling back plate on the outer end faces of the upper flange 1 and the lower flange 2 during the welding process to strengthen them, so as to reduce the inner deformation of the upper flange 1 or the lower flange 2 caused by welding stress.

[0066] During steps 3 to 7, all welds are subjected to surface non-destructive testing, and all welds are polished after passing the test.

[0067] The overall precision machining in step 8 is sequentially flipping back and forth, small cutting amount, and multi-pass symmetrical machining, interspersed with natural aging process.

[0068] Example 6

[0069] As shown in Figures 1 to 5, preferably, a telescopic sleeve of a loading and unloading machine is processed by the processing method of a telescopic sleeve of a loading and unloading machine described in any one of the above items, and the telescopic sleeve of the loading and unloading machine includes an upper flange 1, a lower flange 2, a guide rail 3, a mounting support 4 and a sleeve tube 5, wherein there are two guide rails 3 and multiple mounting supports 4, the upper flange 1 and the lower flange 2 are respectively welded to the two end surfaces of the sleeve tube 5, and the multiple mounting supports 4 are divided into two rows, and the two rows of mounting supports 4 are respectively welded to the two opposite directions of the sleeve tube 5 with smaller straightness, and the top surface of each row of mounting supports 4 and the groove surface of the concave straight groove 4-1 are respectively in the same plane in the full length direction of the sleeve tube 5, and the top surfaces of the two rows of mounting supports 4 and the groove surfaces of the concave straight grooves 4-1 are symmetrical with respect to the center line of the sleeve tube 5, and the two guide rails 3 are respectively welded in the concave straight grooves 4-1 of the two rows of mounting supports 4.

[0070] The upper flange 1 and lower flange 2 are machined from stainless steel sheet metal, with a cross-section featuring a square outer frame and a central circular hole. The inner stoppers of the upper and lower flanges 1 and 2 are welded to the outer stoppers at both ends of the sleeve tube 5. The thickness and shape of the upper and lower flanges, as well as the central inner hole, are machined after welding, and all threaded holes are machined after welding. The upper flange 1 is connected to the suspension head via stopper locating bolts, while the lower flange 2 is connected to the gripper flange via stopper locating bolts. Therefore, the verticality of the upper and lower flanges 1 and 2 relative to the overall center of the sleeve tube 5 is strictly required.

[0071] The guide rail 3 is machined from stainless steel oblong bar stock into a rectangular cross-section strip. The lower end of the guide rail section is placed within the concave straight groove 4-1, and the two are welded together at the side contact area. The three upper working surfaces (top surface and two side surfaces) are machined with post-weld machining. Guide wheels guide the entire length of the three working surfaces of the guide rail 3 to ensure accurate positioning of the fuel assembly during gripper grasping. Therefore, the full-length machining accuracy of the guide rail 3's working surfaces is of paramount importance.

[0072] The mounting support 4 is an arched block made of stainless steel plate, with a concave straight groove 4-1 on the top surface, flat left and right sides, and an arc surface on the bottom surface. The arc surface is welded to the two symmetrical sides of the outer wall of the sleeve tube 5.

[0073] The sleeve tube 5 is a purchased finished stainless steel seamless steel tube. As the carrier of the telescopic sleeve component, it is critical to control the straightness of the entire length. The two opposite directions with smaller straightness need to be used as the welding orientations of the mounting bracket. Symmetrical rectangular holes are opened at both ends of the outer wall of the sleeve tube 5 near the flange position, which are used as windows for subsequent installation and maintenance of other components.

[0074] Each single piece is left with a certain amount of stock before welding, and the intermediate processes are processed in sequence to meet the drawing dimensions. After being welded into an integral part, it is then fine-machined. During the process, effective process measures are taken to reduce welding and machining deformation, and ultimately ensure the straightness, symmetry, flatness and other form and position tolerance requirements of the telescopic sleeve track.

[0075] Example 7

[0076] The present invention discloses a processing method of a telescopic sleeve of a loading and unloading machine, comprising an upper flange 1 (1 piece), a lower flange 2 (1 piece), a guide rail 3 (2 pieces), a mounting support 4 (62 pieces), and a sleeve tube 5 (1 piece);

[0077] The finished sleeve tube 5 (Ф219×8) is purchased, and welding shrinkage and post-weld processing allowance are left in the length direction. As the carrier of the telescopic sleeve component, the full-length straightness is required to be controlled within 1.5mm.

[0078] After the sleeve tube 5 is purchased and returned to the factory, the straightness and roundness of the tube are rechecked and the data is recorded to guide the subsequent welding and machining operations. The two opposite directions with smaller straightness (90° and 270°) are used as the welding orientations for the mounting bracket 4. The subsequent manufacturing processes use this as a reference to align the two ends of the sleeve tube 5, concentrically process the two ends, and make them flush when exposed to light to ensure that the end faces at both ends are perpendicular to the center of the sleeve tube.

[0079] The mounting support 4 is processed into a peripheral shape and arc surface as a single piece, and the top surface is left with a post-weld processing allowance, and the corresponding concave straight groove 4-1 does not need to be processed here.

[0080] Taking one side end face of the sleeve tube 5 as a reference, draw the positioning dimension line of the mounting support 4 on the outer wall of the sleeve tube 5 at the pre-determined assembly welding orientation (90° and 270°). Accurate assembly and spot welding are carried out. Only after verifying that all dimensions are correct can the mounting support 4 and the sleeve tube 5 be welded. During the welding process, the sleeve tube 5 and the mounting support 4 are placed as a whole on the construction platform 6 with a flat surface along the length direction of the construction platform 6. A special gantry clamp fixing tool 7 is used to evenly distribute the clamping at multiple points along the entire length to rigidly fix it to the construction platform to prevent the tube body from deforming due to welding heat input.

[0081] On a CNC gantry boring and milling machine, align and process the top surface of the mounting support 4 and the concave straight groove 4-1 in two directions, ensuring that the top surface and groove surface of the mounting support 4 in two directions are in the same plane in the full length direction, and the top surface and groove surface of the mounting support in two directions are symmetrical with respect to the center line of the sleeve tube 5 (groove surface parallelism 0.06mm, groove surface straightness 0.25mm).

[0082] The guide rail 3 is processed into a long strip with a rectangular cross-section, wherein the 13mm height area at the lower end of the cross-section is placed in the concave straight groove 4-1 for welding and processed into a stop type. The three working surfaces at the upper end (top surface and two side surfaces) are left with post-weld processing allowance, and the length is left with welding shrinkage and post-weld processing allowance. The straightness of the entire length is within 0.5mm.

[0083] Place the lower end of the guide rail 3 section as a whole into the processed concave straight groove 4-1, adjust the guide rail 3 lengthwise reference position (at this point, the guide rail 3 and the sleeve tube 5 have both been processed in length), and weld the guide rail 3 to the mounting bracket 4. During the welding process, place the sleeve tube 5 and the mounting bracket 4 vertically on a flat construction platform 6. When welding the upper guide rail 3, the top surface of the lower mounting bracket 4 is firmly attached to the platform surface (after the upper welding is completed, the lower part is hoisted over to become the upper part. When welding the original lower guide rail, the top surface of the original upper guide rail is firmly attached to the platform surface). Use a special gantry clamp to fix the fixture 7, evenly distributed at multiple points along the entire length for compression, so that it is rigidly fixed to the construction platform to prevent the guide rail 3 from local warping and deformation.

[0084] On the CNC gantry boring and milling machine, align and measure the length of the two end faces of the guide rail, determine the total length of the two ends of the sleeve tube 5 based on the end face of the guide rail 3, and process the external stoppers at both ends of the sleeve tube 5 to ensure that the stopper circles at both ends are concentric.

[0085] The upper flange 1 and lower flange 2 are machined as a single piece into a square-shaped cross-section with a hollow circular center. The internal stoppers that mate with the sleeve tube are machined as a single piece. The thickness, shape, and center bore allowances are left for post-weld machining, and all threaded holes are machined after welding.

[0086] The upper and lower flanges are respectively inserted into the outer ends of the sleeve tube, and positioned and welded. During the welding process, the stainless steel tooling back plate is spot welded on the outer end face of the flange for tensioning to reduce the inner deformation of the flange caused by welding stress.

[0087] During the process, all welds are subjected to surface non-destructive testing, and all welds are polished after passing the test.

[0088] CNC gantry boring and milling machines are used for single-stage clamping and alignment, enabling precision machining of the entire guide rail. Through a process that utilizes "reciprocating rotation, minimal stock removal, multiple symmetrical passes, and interspersed natural aging," stress generated during machining is released, minimizing the impact of machining stress on the overall accuracy of the guide rail.

[0089] Factors affecting quality should be considered in precision machining:

[0090] a. Due to the poor rigidity of the steel pipe, its natural deflection and the bending of the steel pipe itself should be considered during clamping, and the compression amount should be strictly controlled and measured with a meter during compression;

[0091] b. The processing quantity should be verified before processing, and measurements should be interspersed during the processing;

[0092] c. The machining parameters such as cutting amount and rotation speed should be strictly controlled during each step of machining, and coolant should be used to prevent deformation during machining;

[0093] d. During the processing, the clamping should be loosened regularly to observe the deformation and prevent unexpected processing deformation.

[0094] At this point, all the work of overall processing of the telescopic sleeve is completed.

[0095] The telescopic sleeve structure of the present invention is a slender stainless steel tube with a length of nearly 8.7 meters. An upper flange 1 and a lower flange 2 are welded at both ends of the tube. 31 groups (62) of mounting brackets 4 are welded in two symmetrical straight lines on the outer wall of the tube. The guide rail 3 is placed in a concave straight groove 4-1 and welded to the concave straight groove 4-1 to form an integral structure. Since this structure is a stainless steel slender rod-type welded component, the overall rigidity is extremely poor, and coupled with the characteristics of the material itself, it is easy to deform as a whole. However, the processing accuracy required by the design is extremely high, so the overall processing is very difficult. Overall processing technology has always been a difficult point in the mechanical processing industry. The technology of the present invention focuses on solving the technical method of this type of overall processing, which is not a general conventional processing method.

[0096] The working principle of the present invention is as follows:

[0097] As shown in Figures 1 to 6, the present invention discloses a processing method for the telescopic sleeve of a loading and unloading machine. First, the upper flange, lower flange, guide rail, mounting support and sleeve tube are rough-processed, and then two rows of mounting supports are welded on two opposite sides of the sleeve tube with smaller straightness. Then, a CNC gantry boring and milling machine is used to align and process the concave straight grooves. Then, the two guide rails are respectively welded in the two rows of concave straight grooves. Then, the upper flange and the lower flange are respectively inserted into the outer stoppers at both ends of the sleeve tube, positioned and welded, and finally the overall precision processing is performed to complete the processing of the telescopic sleeve of the loading and unloading machine. The straightness, symmetry and flatness of the telescopic sleeve processed by the processing method of the present invention meet the requirements, ensure the accuracy tolerance requirements of the design drawings, and meet various functional requirements of equipment debugging.

[0098] The invention uses two opposite directions of the sleeve tube with smaller straightness as the group welding orientations of the mounting supports, draws the positioning dimension lines of the mounting supports on the outer wall of the sleeve tube corresponding to the group welding orientations, uses multiple gantry splint fixing tools to fix the sleeve tube on the construction platform, and performs welding work on the mounting supports and the sleeve tube to form two opposite rows of mounting supports, which effectively improves the straightness.

[0099] The present invention welds the mounting supports to the sleeve tube and then aligns and processes the top surfaces and concave straight grooves of the two rows of mounting supports on a CNC gantry boring and milling machine to ensure that the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are respectively in the same plane in the full length direction, and the top surfaces of the two rows of mounting supports and the groove surfaces of the concave straight grooves are symmetrical with respect to the center line of the sleeve tube, thereby ensuring symmetry and flatness to the greatest extent.

[0100] The present invention adopts gantry clamping tooling to be evenly distributed at multiple points along the entire length of the sleeve tube for compression, so that the sleeve tube is rigidly fixed on the construction platform, thereby preventing the sleeve tube body from being deformed due to welding heat input and improving the straightness.

[0101] The present invention adopts gantry clamp fixing tooling evenly distributed at multiple points along the entire length of the guide rail and the sleeve tube for compression, so that the guide rail is rigidly fixed on the construction platform, thereby preventing local warping and deformation of the guide rail and improving symmetry and flatness.

[0102] After technical breakthroughs, the present invention ultimately ensured that all dimensions met the precision tolerances specified in the design drawings. In-plant assembly and commissioning tests verified that relevant functional tests met design requirements. The loader and unloader assembly, assembled using the telescopic sleeves processed using the present invention, has been put into operation at a nuclear power plant with positive results.

[0103] The preferred embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments. Various changes can be made within the knowledge of ordinary technicians in this field without departing from the scope of the present invention.

[0104] Many other changes and modifications can be made without departing from the spirit and scope of the present invention. It should be understood that the present invention is not limited to the specific embodiments, and the scope of the present invention is defined by the appended claims.

Claims

1. A method for processing a telescopic sleeve of a loading and unloading machine, characterized in that: The following steps are involved: Step 1: Roughly process the upper flange (1), the lower flange (2), the guide rail (3), the mounting support (4) and the sleeve tube (5), wherein the guide rails (3) are two and the mounting support (4) are multiple; Step 2: recheck the straightness and roundness of the sleeve tube (5), and use the two opposite directions with smaller straightness of the sleeve tube (5) as the assembly welding orientations for the mounting support (4); Step 3: Using the end face of one side of the sleeve tube (5) as a reference, draw a positioning dimension line of the mounting support (4) on the outer wall of the sleeve tube (5) corresponding to the assembly welding position, fix the sleeve tube (5) on the construction platform (6) using a plurality of gantry clamping tooling (7), and weld the mounting support (4) and the sleeve tube (5) to form two opposite rows of mounting supports (4); Step 4: Align and process the top surfaces of the two rows of mounting supports (4) and the concave straight grooves (4-1) on a CNC gantry boring and milling machine, ensuring that the top surfaces of the two rows of mounting supports (4) and the groove surfaces of the concave straight grooves (4-1) are respectively in the same plane in the full length direction, and the top surfaces of the two rows of mounting supports (4) and the groove surfaces of the concave straight grooves (4-1) are symmetrical with respect to the center line of the sleeve tube (5); Step 5: Place the lower end of the guide rail (3) in its entirety into the concave straight groove (4-1), adjust the reference position of the guide rail (3) in the length direction, and weld the guide rail (3) and the mounting support (4); Step 6: Align and measure the length of the two end faces of the guide rail (3) on a CNC gantry boring and milling machine, determine the total length of the two ends of the sleeve tube (5) based on the end faces of the guide rail (3), and process the outer stoppers at both ends of the sleeve tube (5) to ensure that the outer stopper circles at both ends are concentric; Step 7: Insert the upper flange (1) and the lower flange (2) into the outer ends of the sleeve tube (5) respectively, and weld them in position; Step 8: Use a CNC gantry boring and milling machine to clamp and align in sequence, perform overall precision machining, and complete the machining of the telescopic sleeve of the loader and unloader.

2. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: The rough processing process of the upper flange (1) and the lower flange (2) in step 1 is as follows: the upper flange (1) and the lower flange (2) are processed into a special-shaped structure with a square outer frame and a central inner circular hole in cross section, and the inner stop of the upper flange (1) and the lower flange (2) matching the sleeve tube (5) is processed, the thickness of the upper flange (1) and the lower flange (2), the outer frame and the central inner hole are all left with a post-welding processing allowance, and all the connecting threaded holes are processed after the upper flange (1) and the lower flange (2) are welded to the sleeve tube (5); The rough processing process of the guide rail (3) is as follows: the guide rail (3) is processed into a long strip structure with a rectangular cross section, the lower end of the guide rail (3) is processed into a stopper type, the lower end of the guide rail (3) is placed in a concave straight groove (4-1) for welding, the top surface and two side surfaces of the guide rail (3) are left with post-welding processing allowances, the length of the guide rail (3) is left with welding shrinkage and post-welding processing allowances, and the straightness of the entire length is within 0.5 mm; The rough processing process of the mounting support (4) is as follows: the plurality of mounting supports (4) are processed into a square structure with a top surface and two side surfaces being flat and a bottom surface being an arc surface, the arc surface being adapted to the outer wall of the sleeve tube (5), the top surface of the mounting support (4) is left with a post-welding processing allowance, and the concave straight groove (4-1) corresponding to the mounting support (4) is not processed at this time; The rough processing process of the sleeve tube (5) is as follows: welding shrinkage and post-welding processing allowance are left in the length direction of the sleeve tube (5), and the straightness of the entire length of the sleeve tube (5) is controlled within 1.5 mm.

3. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: In step 2, it is also necessary to align the two end faces of the sleeve tube (5), concentrically process the two end faces, and make them flush when exposed to light, so as to ensure that the two end faces are perpendicular to the center of the sleeve tube (5).

4. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: The step 3 specifically comprises: taking the end face of one side of the sleeve tube (5) as a reference, drawing a positioning dimension line of the mounting support (4) on the outer wall of the sleeve tube (5) corresponding to the assembly welding position, accurately assembling and spot welding, and after verifying that all dimensions are correct, welding the mounting support (4) and the sleeve tube (5) to form two opposite rows of mounting supports (4); during the welding process, placing the sleeve tube (5) on the construction platform (6) along the length direction of the construction platform (6), and using a plurality of gantry clamp fixing fixtures (7) to rigidly fix the sleeve tube (5) on the construction platform (6).

5. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: The gantry clamp fixing tool (7) comprises an upper clamp (7-1), a lower clamp (7-2) and two screws (7-3). Through holes are provided on both sides of the upper clamp (7-1). The upper end of the upper clamp (7-1) is a plane, and the lower end of the upper clamp (7-1) is a circular arc surface, which is matched with the outer wall of the sleeve tube (5). The lower end of the lower clamp (7-2) is a plane, and the upper end of the lower clamp (7-2) is a circular arc surface, which is matched with the outer wall of the sleeve tube (5). The upper end surface of the construction platform (6) is a plane, and the construction platform (6) The upper end surface is provided with a plurality of slide grooves (6-1) along the length direction, the large diameter ends of the two screw rods (7-3) are limitedly located in the slide grooves (6-1) and can slide along the slide grooves (6-1), the small diameter ends of the two screw rods (7-3) pass through the through holes on both sides of the upper clamping plate (7-1) and are connected with nuts, and a plurality of gantry clamping plate fixing fixtures (7) are evenly distributed at a plurality of points along the entire length of the sleeve tube (5) to compress the sleeve tube (5), so that the sleeve tube (5) is rigidly fixed on the construction platform (6), and the sleeve tube (5) is prevented from being deformed due to welding heat input.

6. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: The welding process of the guide rail (3) and the mounting support (4) in step 5 is as follows: the sleeve tube (5) is placed on the construction platform (6) along the length direction of the construction platform (6); when welding the upper guide rail (3), the lower side of the lower mounting support (4) is firmly attached to the construction platform (6); a gantry clamp fixing tool (7) is evenly distributed at multiple points along the entire length of the sleeve tube (5) for compaction; after the upper guide rail (3) is welded, the lower mounting support (4) is turned around to become the upper mounting support (4); when welding the lower guide rail (3), the top surface of the original upper guide rail (3) is firmly attached to the construction platform (6); at the same time, a gantry clamp fixing tool (7) is evenly distributed at multiple points along the entire length of the sleeve tube (5) for compaction, so that the sleeve tube (5) is rigidly fixed on the construction platform (6) to prevent the guide rail (3) from being partially lifted and deformed, and the welding of the lower guide rail (3) is completed.

7. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 2, characterized in that: The step 7 is to insert the inner stoppers of the upper flange (1) and the lower flange (2) into the outer stoppers at both ends of the sleeve tube (5) respectively, and position and weld them. During the welding process, a stainless steel tooling back plate is spot welded on the outer end faces of the upper flange (1) and the lower flange (2) for tightening, so as to reduce the inner deformation of the upper flange (1) or the lower flange (2) caused by welding stress.

8. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: During steps 3 to 7, all welds are subjected to surface non-destructive testing, and all welds are polished after passing the test.

9. The method for processing a telescopic sleeve of a loading and unloading machine according to claim 1, characterized in that: The overall precision machining in step 8 is sequentially back and forth flipping, small cutting amount, and multi-pass symmetrical machining, and is interspersed with natural aging process.

10. A telescopic sleeve for a loading and unloading machine, characterized in that: The telescopic sleeve of a loading and unloading machine is processed by the processing method of any one of claims 1 to 9, and the telescopic sleeve of the loading and unloading machine comprises an upper flange (1), a lower flange (2), a guide rail (3), a mounting support (4) and a sleeve tube (5), wherein there are two guide rails (3) and a plurality of mounting supports (4), the upper flange (1) and the lower flange (2) are respectively welded to the two end surfaces of the sleeve tube (5), the plurality of mounting supports (4) are equally divided into two rows, the two rows of mounting supports (4) are respectively welded to two opposite directions of the sleeve tube (5) with smaller straightness, the top surface of each row of mounting supports (4) and the groove surface of the concave straight groove (4-1) are respectively in the same plane in the full length direction of the sleeve tube (5), the top surfaces of the two rows of mounting supports (4) and the groove surfaces of the concave straight grooves (4-1) are symmetrical with respect to the center line of the sleeve tube (5), and the two guide rails (3) are respectively welded in the concave straight grooves (4-1) of the two rows of mounting supports (4).

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