Efficient rotor excircle de-weighting method based on numerical control boring and milling center

Abstract

The invention discloses an efficient rotor excircle de-weighting method based on a numerical control boring and milling center. The high-efficiency de-weighting method for the outer circle of the rotor comprises the following steps: obtaining unbalance amount information through a dynamic balance test performed by the rotor; obtaining a removal size based on the unbalance information; and based on the numerical control boring and milling center, the size is machined and removed. By means of the efficient de-weighting method, unbalance information is found firstly, then the removal size obtained based on the unbalance information is removed, the removal size is machined through the numerical control boring and milling center, only one-time dynamic balance test needs to be carried out, machining is directly carried out through the numerical control boring and milling center, the dynamic balance de-weighting efficiency is improved, the rotor manufacturing period is shortened, and the production economy is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of dynamic balancing of large-sized rotors of nuclear main pumps, and particularly to an efficient method for removing weight from the outer circle of a rotor based on a numerical control boring and milling center. Background Art

[0002] The dynamic balancing of the large-sized rotor of the nuclear main pump is to perform dynamic balancing by assembling rotor components such as impellers, shaft sleeves, balance drums, and flywheels together. Its weight is about 20 tons, the size is 1000 mm in diameter and about 5000 mm in length, and weight removal is required on the outer circle of the flywheel. Dynamic balancing is a key process in pump manufacturing, and the numerical value seriously affects key indicators such as the vibration and noise of the pump rotor. There are two methods in related technologies to achieve dynamic balance: one method is to remove weight by grinding when the dynamic unbalance amount is small; the other method is when the dynamic unbalance amount is large, the rotor is disassembled, and the dynamic unbalance amount is removed on a certain part through processing equipment. In the case of a large dynamic unbalance amount, the operation is cumbersome, and the work process of disassembling the rotor - removing weight - assembling the rotor - dynamic balancing needs to be carried out. It is difficult to meet the design requirements in one go, and basically the above operations are cycled, resulting in a long manufacturing cycle, waste of manpower and material resources, and reduced efficiency and economy. Summary of the Invention

[0003] The present invention aims to solve at least one of the technical problems existing in the prior art or related technologies.

[0004] In view of this, the present invention provides an efficient method for removing weight from the outer circle of a rotor based on a numerical control boring and milling center. Through the efficient weight removal method, first find the unbalanced position, and then remove the removal size obtained based on the unbalanced position. The removal size is processed by a numerical control boring and milling center. Only one dynamic balance test is required. Direct processing by the numerical control boring and milling center improves the efficiency of dynamic balance weight removal, shortens the rotor manufacturing cycle, and improves production economy.

[0005] Specifically, the following technical solutions are included:

[0006] The present invention provides an efficient method for removing weight from the outer circle of a rotor based on a numerical control boring and milling center. The efficient method for removing weight from the outer circle of a rotor includes the following steps:

[0007] Obtain unbalance amount information through a dynamic balance test of the rotor;

[0008] Obtain a removal size based on the unbalance amount information;

[0009] Process the removal size based on a numerical control boring and milling center.

[0010] Optionally, the obtaining of the unbalance amount information includes:

[0011] Obtain the position of the unbalance amount;

[0012] Obtain the weight information that is not measured.

[0013] Optionally, the obtaining and removing dimension includes:

[0014] Based on the weight information being transformed into the removed volume information, obtain the rotor-to-arc surface dimension information;

[0015] Wherein, the arc surface dimension information includes the arc surface included angle removed on the outer surface of the rotor, the total length, the total width, and the total depth.

[0016] Optionally, the total width is the removed dimension in the axial direction of the rotor axis, the total length refers to the arc surface length corresponding to the arc surface included angle at the unbalanced position, and the total depth is the removed dimension in the radial direction of the rotor.

[0017] Optionally, the processing of the removed dimension includes:

[0018] Place the rotor in the CNC boring and milling center so that the center line of the rotor is concentric with the spindle center line of the CNC boring and milling center;

[0019] Divide the total depth into multiple sub-depths, and based on the multiple sub-depths, divide the removed dimension into multiple arc surface layers;

[0020] Remove the arc surface layer through a tool;

[0021] Repeat the above steps until the sum of the depths of the multiple arc surface layers is equal to the total depth.

[0022] Optionally, the dividing of the removed dimension into multiple arc surface layers includes:

[0023] Based on the unbalanced position, set a starting point, and starting from the starting point, first use the sub-width as the decreasing amount in the total width direction;

[0024] The tool rotates clockwise and / or counterclockwise within the range of the arc surface included angle at the unbalanced position to remove the dimension with the sub-depth;

[0025] Repeat the previous step until the sum of the removed sub-widths is equal to the total width.

[0026] Optionally, the sub-width is from 0.01 mm to 1 mm.

[0027] Optionally, the sub-depth is from 0.01 mm to 0.5 mm.

[0028] Optionally, the tool is a ball-end milling cutter with a diameter of 8 mm, 10 mm, or 12 mm.

[0029] Optionally, the removed volume projects as a fan-shaped ring on the radial plane of the rotor.

[0030] The high-efficiency weight removal method for the outer circle of the rotor based on the CNC boring and milling center provided by the embodiment of the present invention, wherein the high-efficiency weight removal method includes first performing a dynamic balance test on the rotor, obtaining the positions that cause the rotor imbalance according to the dynamic balance test, then obtaining the required removal dimensions according to the imbalance positions, and finally uploading the relevant information of the dimensions to the CNC boring and milling center. At the same time, placing the rotor on the CNC boring and milling center, operating on the outer circle of the rotor through the uploaded relevant information and the tool, and machining the required removal dimensions of the rotor. If the dynamic balance test is accurate, the obtained relevant information is accurate, and the machining of the CNC boring and milling center based on this information is accurate, so that the dynamic balance requirements of the rotor can be achieved with one dynamic balance test and one machining, improving the work efficiency of dynamic balance weight removal, shortening the production cycle of the rotor, greatly reducing the use of human and material resources, and improving the economy of rotor production.

[0031] The above description is only an overview of the technical solution of this application. In order to be able to understand the technical means of this application more clearly, it can be implemented according to the content of the specification. And in order to make the above and other purposes, features and advantages of this application more obvious and understandable, the specific embodiments of this application are specifically described below. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] In order to more clearly illustrate the technical solutions in the embodiments of the present invention, the following will briefly introduce the drawings required for the description of the embodiments. Obviously, the following drawings are only some embodiments of the present invention. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0033] Figure 1 FIG. is a flowchart of the steps of the high-efficiency weight removal method for the outer circle of the rotor according to an embodiment of the present invention;

[0034] Figure 2 FIG. is a schematic diagram of depth weight removal according to an embodiment of the present invention;

[0035] Figure 3 FIG. is a schematic diagram of width weight removal according to an embodiment of the present invention.

[0036] Among them, Figure 2 and Figure 3 The corresponding relationship between the reference numerals and the component names in the figures is as follows:

[0037] 100 Rotor, 110 Width starting point, 120 Width ending point, 130 Sub-width, 140 Depth starting point, 150 Depth ending point, 160 Sub-depth, 170 Length starting point, 180 Length ending point, α Arc surface angle. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0038] Next, in combination with the accompanying drawings in the embodiments of the present invention, the technical solutions in the embodiments of the present invention will be clearly and completely described. Obviously, the described embodiments are part of the embodiments of the present invention, rather than 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 efforts belong to the scope of protection of the present invention.

[0039] Before further elaborating on the embodiments of the present invention, the directional terms involved in the embodiments of the present invention, such as "upper part", "lower part", and "side part", do not have the meaning of limiting the protection scope of the present invention.

[0040] To make the technical solutions and advantages of the present invention clearer, the embodiments of the present invention will be further described in detail below in combination with the accompanying drawings.

[0041] Figure 1 It is a step flow chart of an efficient rotor outer diameter weight removal method according to an embodiment of the present invention.

[0042] As Figure 1 shown, an embodiment of the present invention provides an efficient rotor outer diameter weight removal method based on a CNC boring and milling center. The efficient rotor outer diameter weight removal method includes the following steps:

[0043] Step 1, obtain unbalance amount information through a dynamic balance test of the rotor;

[0044] Step 2, obtain the removal dimension based on the unbalance amount information;

[0045] Step 3, machine the removal dimension based on the CNC boring and milling center.

[0046] Among them, the efficient weight removal method includes first performing a dynamic balance test on the rotor 100, obtaining the unbalanced position that causes the rotor 100 according to the dynamic balance test, then obtaining the required removal dimension according to the unbalanced position, and finally uploading the relevant information of the dimension to the CNC boring and milling center. At the same time, place the rotor 100 on the CNC boring and milling center, and operate on the outer diameter of the rotor 100 through the uploaded relevant information and the tool to machine the required removal dimension of the rotor 100. If the dynamic balance test is accurate, the obtained relevant information is accurate, and the machining of the CNC boring and milling center based on this information is accurate, so that one dynamic balance test and one machining can meet the dynamic balance requirements of the rotor 100, improve the working efficiency of dynamic balance weight removal, shorten the manufacturing cycle of the rotor 100, greatly reduce the use of human and material resources, and improve the economy of rotor 100 production.

[0047] It should be noted that the rotor 100 is usually a component, including the rotor body and other components inside it. It can be understood that this application is applicable to the case of a large dynamic unbalance. According to the standard, the dynamic unbalance of the rotor is not allowed to exceed 30 grams. If it exceeds, it is considered to have a large balance.

[0048] In a feasible implementation, the obtaining of the unbalance information includes:

[0049] Obtaining the position of the unbalance;

[0050] Obtaining the weight information of the unbalance.

[0051] Among them, the position and weight of the unbalance are measured by the dynamic balancing machine according to the rotor workpiece being measured while rotating at high speed, and the circumferential position and weight of the unbalance are measured. Through the circumferential position and weight of the unbalance, the staff can calculate the specific removal volume information.

[0052] It should be noted that the rotor is placed on the bracket of the dynamic balancing machine, and the dynamic balancing machine drives the rotor to rotate at high speed. The vibration sensor on the bracket of the dynamic balancing machine captures the angular value (circumferential position) and weight value of the vibration point on the circumference of the rotor.

[0053] In a feasible implementation, obtaining the removal dimensions includes:

[0054] Based on the weight information being converted into removal volume information, obtaining the arc surface dimension information of the rotor;

[0055] Among them, the arc surface dimension information includes the arc surface included angle, total length, total width, and total depth removed on the outer surface of the rotor.

[0056] Among them, according to the obtained unbalance position and weight information being converted into removal volume information, and based on the total length, total width, and total depth removed on the outer surface of the rotor.

[0057] It can be understood that usually a rectangle is set at the circumferential position of the unbalance, and based on the weight information of the unbalance, the depth is increased to mention the removal volume. To ensure aesthetics, the projection of the removal volume on the radial plane of the rotor is in the shape of a sector ring. A sector ring refers to a part intercepted by a sector from a circular ring, as Figure 2 shown.

[0058] In a feasible implementation, the total width is the removal dimension in the axial direction of the rotor 100, the total length is the arc length corresponding to the arc surface included angle α of the unbalance position, and the total depth is the removal dimension in the radial direction of the rotor 100.

[0059] Among them, by obtaining the total length, total width, and total depth of the dimensions to be removed, the machining of the outer surface of the rotor 100 by the CNC boring and milling center can be achieved, thereby removing the dynamic unbalance amount and enabling the rotor 100 to meet the dynamic balance requirements.

[0060] It should be noted that since the outer surface of the rotor 100 is arc-shaped and the unbalanced position is a region corresponding to a certain angle on the axis of the rotor 100, the shape of the removed dimension is rectangular in the direction of the front view (the view when the line of sight is perpendicular to the axis of the rotor), as Figure 3 shown. The shape of the removed dimension is the difference between two sectors, that is, a fan-shaped ring, in the direction of the side view (the view when the line of sight is parallel to the axis of the rotor), as Figure 2 shown. The first sector is the sector formed by the angle α of the unbalanced position and the outer arc surface of the rotor 100, and the second sector is the sector formed by the angle α of the unbalanced position and the inner arc surface of the rotor 100. It can be understood that the inner arc surface is the outer arc surface of the rotor 100 after the total depth is removed.

[0061] In a feasible implementation manner, the machining of the removed dimension includes:

[0062] Place the rotor in the CNC boring and milling center so that the center line of the rotor is concentric with the center line of the main shaft of the CNC boring and milling center;

[0063] Divide the total depth into multiple sub-depths, and based on the multiple sub-depths, divide the removed dimension into multiple arc layers;

[0064] Remove the arc layers through a tool;

[0065] Repeat the above steps until the sum of the depths of the multiple arc layers is equal to the total depth.

[0066] Among them, it is usually best to set the center line of the rotor 100 to be concentric with the center line of the main shaft of the CNC boring and milling center; divide the total depth into multiple sub-depths 160, and each sub-depth 160 forms an arc layer (fan-shaped ring); remove the multiple arc layers through a tool respectively until the removed multiple arc layers reach the total depth (the distance between the depth starting point 140 and the depth ending point 150), and then the tool stops. Removing in layers can, on the one hand, reduce the depth removed by the tool at one time, thereby reducing the instantaneous load of the tool, increasing the service life of the tool, and reducing the frequency and cost of replacing the tool; on the other hand, removing in layers ensures that the depth of each layer of cutting is controlled within a reasonable range by gradually removing the material, thereby reducing the vibration and deformation caused by excessive cutting and improving the machining accuracy of the removed dimension. At the same time, removing in layers can also reduce the surface roughness and obtain a smoother machining surface, meeting the requirements of the surface accuracy of the rotor 100.

[0067] It is understandable that the projection of the removed volume on the radial plane of the rotor is fan-shaped. Then, the starting position for removing the next arc layer should be processed starting from the ending position of the previous arc layer, which can ensure the smoothness of the removed position on the rotor and improve the machining accuracy.

[0068] In a feasible implementation manner, dividing the removed dimension into multiple arc layers includes:

[0069] Based on the unbalanced position, set a starting point. Starting from the starting point, first decrease by the sub-width in the total width direction;

[0070] The tool rotates clockwise and / or counterclockwise within the range of the arc angle of the unbalanced position, removing a dimension with a sub-depth of the sub-depth;

[0071] Repeat the previous step until the sum of the removed sub-widths is equal to the total width.

[0072] Among them, select a starting point in the entire unbalance position area, usually at a corner, and machine along the axis direction of the rotor 100, that is, gradually machine in the total width direction. At the same time, divide the total width into multiple sub-widths 130. The tool machines a dimension of one sub-width 130 each time, dividing the total width into multiple sub-widths 130 and machining in segments. On the one hand, it can achieve simultaneous machining with two-direction tool arrangement, improving the machining efficiency. On the other hand, machining in segments can reduce the risk during the machining process of the CNC boring and milling center and reduce potential safety hazards caused by the workpiece being too large or too heavy. Through width-segmented machining, the position and stability of the workpiece can be better controlled, and the operation safety can be improved. Within the range of the arc angle α of the unbalanced position, machine in the total width (the distance from the width starting point 110 to the width ending point 120) direction according to the sub-width 130. After machining one layer of sub-width and arc length, remove the next fan-shaped ring with a sub-depth. After machining the total width once, one layer of arc layer is machined. The tool returns to the position at the end of the previous arc layer until the depth of multiple arc layers is equal to the total depth.

[0073] It should be noted that it can be simultaneous machining with two-direction tool arrangement. The simultaneous machining with two-direction tool arrangement means that one tool machines Figure 3 in the left-to-right direction, and the other tool machines Figure 3 in the right-to-left direction in , achieving two-way simultaneous machining and improving the machining efficiency of the removed dimension.

[0074] It is understandable that clockwise or counterclockwise refers to the machining direction, that is, down milling or up milling, which is the rotation of the tool along the rotor.

[0075] In a feasible implementation manner, the sub-width 130 is from 0.01 mm to 1 mm.

[0076] Among them, in this embodiment, the divided width can be selected in the range of 0.1 mm to 0.5 mm. Such a range can ensure both processing efficiency and processing accuracy. That is to say, if the size of the divided width is too small, although the processing accuracy is improved, the processing efficiency is greatly reduced; if the size of the divided width is too large, although the processing efficiency is ensured, the processing accuracy is lost. Therefore, after comprehensive consideration, the divided width is selected as 0.1 mm to 0.5 mm.

[0077] In a feasible implementation manner, the divided depth 160 is 0.01 mm to 0.5 mm.

[0078] Among them, in this embodiment, the divided depth can be selected as 0.1 mm to 0.3 mm. Such a range can ensure both processing efficiency and processing accuracy. That is to say, if the size of the divided depth is too small, although the processing accuracy is improved, the processing efficiency is greatly reduced; if the size of the divided depth is too large, although the processing efficiency is ensured, the processing accuracy is lost. Therefore, after comprehensive consideration, the divided width is selected as 0.1 mm to 0.5 mm.

[0079] It can be seen that different divided depths and divided widths can be selected according to the actual situation for step-by-step processing, and a suitable processing decrement can be selected by comprehensively considering the requirements of rotor processing accuracy and processing efficiency.

[0080] In a feasible implementation manner, the tool is a ball-end mill with a diameter of 8 mm, 10 mm or 12 mm.

[0081] Among them, the 8-mm ball-end mill is suitable for processing small-sized complex features and can enter a smaller space. However, the 8-mm ball-end mill has low rigidity and is prone to vibration, requiring a small cutting depth and high-speed feed. The 10-mm ball-end mill can balance accuracy and efficiency and is the size of the ball-end mill selected for most processing. However, it has limitations in processing extremely fine or extremely large curved surfaces. The 12-mm ball-end mill is suitable for workplaces with large cutting depths and large feeds, has high processing efficiency, can quickly process large curved surfaces, has slower tool wear and longer service life, but cannot process small features and may require a ball-end mill with a smaller diameter for detail processing.

[0082] Specifically, as Figure 2 and Figure 3 shown, using a small-sized ball-end mill, starting from the width starting point 110, with the divided depth 160 as the radius, first divide by the divided width 110 as the decrement in the width direction, and process an arc layer with a depth of the divided depth 160. When the small-sized ball-end mill reaches the width end point 120 position, it is one cycle. Then the small-sized ball-end mill returns to the corner of the lower surface of the upper arc surface (corresponding to the child at the width starting point 110), and processes to the width end point 120 at the divided depth 160 until the depth of multiple arc layers reaches the total depth.

[0083] It should be noted that since the area of the machining region is much larger than the tool diameter, there can be tool arrangement increment amounts in two directions for repeated machining during the machining process. That is to say, a small-diameter ball-end mill can be set at both the width start point 110 and the width end point 120. The two small-diameter ball-end mills move relative to each other until they meet, completing the machining of one layer of the arc surface layer. Then they return to the corresponding positions of the width start point 110 and the width end point 120 respectively, and re-perform the machining of the second layer of the arc surface layer. The simultaneous machining of the two small-diameter ball-end mills can improve the machining efficiency of the rotor 100.

[0084] It can be understood that the length start point 140 and the length end point 150 are determined according to the arc surface angle α of the unbalanced position. The intersection points of the rays at both ends of the arc surface angle α of the unbalanced position with the outer arc surface of the rotor 100 form an arc on the arc surface, and the two ends of this arc are respectively the length start point 170 and the length end point 180. Since the position information in the depth direction is calculated based on the arc surface angle α and the rotor radius, and the depth is positioned along the arc surface angle α, when the depth changes, the position of the width start point has slight changes.

[0085] In the present invention, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance. The term "plurality" means two or more, unless otherwise clearly defined.

[0086] After considering the specification and practicing the present invention disclosed herein, those skilled in the art will readily conceive of other embodiments of the present invention. The present invention is intended to cover any variations, uses, or adaptations of the present invention, which follow the general principles of the present invention and include common general knowledge or conventional technical means in the technical field not disclosed by the present invention. The specification and examples are only considered to be exemplary.

[0087] The above are only the preferred embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent replacements, improvements, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. An efficient rotor outer circle weight removal method based on a numerically controlled boring and milling center, characterized in that, The efficient rotor outer circle weight removal method includes the following steps: Obtain unbalance information through the dynamic balance test of the rotor; Obtain the removal dimension based on the unbalance information; Machine the removal dimension based on a CNC boring and milling center.

2. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to claim 1, wherein The obtaining of the unbalance information includes: Obtain the position of the unbalance; Obtain the weight information of the unbalance.

3. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to claim 2, characterized in that The obtaining of the removal dimension includes: Based on the conversion of the weight information into removal volume information, obtain the arc surface dimension information of the rotor; Wherein, the arc surface dimension information includes the arc surface included angle, total length, total width, and total depth removed from the outer surface of the rotor.

4. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to claim 3, characterized in that The total width is the removal dimension in the axial direction of the rotor axis, the total length refers to the arc surface length corresponding to the arc surface included angle at the unbalance position, and the total depth is the removal dimension in the radial direction of the rotor.

5. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to claim 3, characterized in that, The machining of the removal dimension includes: Place the rotor in the CNC boring and milling center so that the center line of the rotor is concentric with the spindle center line of the CNC boring and milling center; Divide the total depth into multiple sub - depths, and based on the multiple sub - depths, divide the removal dimension into multiple arc surface layers; Remove the arc surface layers with a tool; Repeat the above steps until the sum of the depths of the multiple arc surface layers is equal to the total depth.

6. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to claim 5, characterized in that, The dividing of the removal dimension into multiple arc surface layers includes: Based on the unbalance position, set a starting point, and starting from the starting point, first use the sub - width as the decreasing amount in the total width direction; The tool rotates clockwise or counterclockwise within the range of the arc surface included angle at the unbalance position to remove a dimension with a depth of the sub - depth; Repeat the previous step until the sum of the removed sub - widths is equal to the total width.

7. The high-efficiency rotor outer circle weight removal method based on a numerically controlled boring and milling center according to claim 6, wherein The sub - width is from 0.01 mm to 1 mm.

8. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to claim 5, characterized in that, The sub - depth is from 0.01 mm to 0.5 mm.

9. The high-efficiency rotor outer diameter weight removal method based on a numerically controlled boring and milling center according to any one of claims 5 to 8, characterized in that The tool is a ball - end milling cutter with a diameter of 8 mm, 10 mm, or 12 mm.

10. The high-efficiency rotor outer circle weight removal method based on a numerically controlled boring and milling center according to any one of claims 3 to 9, characterized in that, The removed volume projects as a fan - shaped ring on the radial plane of the rotor.

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