Efficient machining method for dense hole series of large conical part

Abstract

An efficient machining method for a large conical part dense hole system comprises the steps that firstly, a neutral plane projection of each hole in a steel plate unfolding state is drawn, and a gas cutting sample plate is drawn with the inward deviation X of the projection size as the sample plate size; then marking out position lines of each hole on the workpiece to be processed, aligning a gas cutting sample plate with each hole position, and pre-cutting a bottom hole of each hole by using gas cutting equipment; then the workpiece is clamped and fixed through the fixing assembly; a rough boring cutter is used for conducting rough boring machining on all holes in the 1 / 3-1 / 2 area below the workpiece; a fine boring cutter is replaced to machine all the unthreaded holes to the finished product size; the fixing assembly is loosened, the workpiece is adjusted to rotate, the unmachined area of the workpiece is located below the workpiece, alignment is conducted with the small-end inner hole as the reference after adjustment, and the inner bottom hole in the other 1 / 3-1 / 2 area is machined to the size of a finished product; and the workpiece continues to be adjusted until all area holes are machined. The method is suitable for batch machining of all the holes in the large-angle conical surface, and reliable theoretical and practical bases are provided for machining of parts of the type.

Description

Technical Field

[0001] The invention relates to the technical field of mechanical processing, in particular to a high-efficiency processing method for a dense hole system of a large-scale tapered part. Background Art

[0002] In the field of machining, it is difficult to process dense holes on the surface of large conical parts. Take the cone section used in the kiln head of the rotary kiln as an example. Its structure is as follows: Figure 1-2 As shown in the figure, its outer diameter φD is generally above 6000mm, the small end diameter φd is generally above 2000mm, and its taper is α. Hundreds of evenly distributed vertical light holes with a size of φAmm need to be processed on its conical surface. The positional form and position tolerance of each light hole is required to be 0.3~0.5mm, the size tolerance of the hole is (0, +0.1~+0.3)mm, the roughness is Ra6.3, and the total thickness δ of the steel plate of the processed part is above 80mm. It can be seen from the figure that there are many holes and the holes are arranged relatively densely, so related pipe fittings need to be arranged; the entire hole system is parallel to the axis of the conical part, not perpendicular to the conical surface; if it is necessary to process the conical surface part with a dense hole system, due to the limitation of its shape, it is difficult to take into account both the processing accuracy and processing efficiency of the hole system on the conical surface.

[0003] Due to the large diameter of the cone section, the large angle of the cone surface, and the strict requirements for the position relationship of each hole, if conventional processing methods are used, the processing and manufacturing accuracy requirements of the cone section cannot be met and the efficiency is very low.

[0004] The conventional processing methods for this type of parts are as follows: Method 1: Do not pre-cut the bottom hole when cutting the material. Use a large boring machine or gantry milling machine to mill a plane at each light hole, and then use drilling or trepanning to remove the excess material in the hole; Method 2: When cutting the material, air-cut the bottom hole of each hole perpendicular to the conical surface, and then use a single-edge boring tool on a large boring machine to rough and fine bore the hole, or use an interpolation tool disc with circumferential edges to perform spiral interpolation on the hole.

[0005] However, the above method is difficult to implement in the dense hole system processing of this type of parts. The main reason is that the cone angle of the part is large and there is no condition for milling a plane, so method one is difficult to implement; when using method two, the longest cantilever distance of the machine tool is generally more than 2500mm. At this time, the spindle rigidity is poor, and the radial force generated by the peripheral blade processing will cause tool vibration during the processing. The tool vibration can only be alleviated by reducing the cutting depth and feed rate, which will lead to long processing time. It is not suitable for use in batch hole processing. Summary of the Invention

[0006] The purpose of the present invention is to propose an efficient processing method for dense hole systems of large conical parts. The method is suitable for batch processing of holes on large-angle conical surfaces, improves processing efficiency, and provides a reliable theoretical and practical basis for the processing of this type of parts.

[0007] The technical solution adopted by the present invention is: a high-efficiency processing method for a dense hole system of a large conical part, setting the hole size processed by the conical surface to φAmm, comprising the following steps: S1. First, draw the neutral plane projection of each hole in the expanded steel plate, and use the projection size offset inward by X as the template size, with X ≥ 30mm, to draw the gas cutting template; then draw the position lines of each hole on the workpiece to be processed, align the gas cutting template with each hole position, and use the gas cutting equipment perpendicular to the inner conical surface of the workpiece to pre-cut the bottom hole of each hole; S2, placing the large end of the workpiece processed in step S1 on the motorized roller, supporting the small end, and then clamping and fixing the workpiece using a fixing assembly; S3. Use a rough boring tool to perform rough boring on the holes in the lower 1 / 3-1 / 2 area of the workpiece, and expand the pre-cut bottom hole to about φA-50~60mm; replace the fine boring tool and process the light holes in the rough boring area to the finished size; Then loosen the fixing components, use the overhead crane and electric rollers to adjust the rotation of the workpiece so that the unprocessed area is located below the workpiece. After adjustment, use the inner hole of the small end as a reference to align and open the coordinates, and use the same method to process the bottom holes in the other 1 / 3-1 / 2 area to the finished product size; continue to adjust the workpiece until the processing of holes in all areas is completed.

[0008] The processing method described in the present invention is mainly suitable for batch processing of holes on large-angle conical surfaces, which improves processing efficiency and provides a reliable theoretical and practical basis for the processing of this type of parts. By optimizing the entire process steps and designing a non-circular gas-cut bottom hole template, the allowance is removed to the maximum extent, the subsequent processing volume is reduced, and efficiency is improved; by designing fixed tooling and clamping methods, the workpiece is placed vertically on a large boring machine to ensure that the stability and rigidity of the workpiece during processing reach the best. At the same time, considering that the overall size of the workpiece is large, most machine tools cannot complete the processing at one time. Based on this, the processing process of subsequent holes is optimized, and in conjunction with the above-mentioned fixed tooling, a zone-by-zone and step-by-step processing method is adopted to improve processing accuracy and efficiency and reduce wear on the machine tool.

[0009] As a preferred solution, in step S1, the projection size is offset inward by 30 mm as the template size.

[0010] As a preferred solution, the card installation process in step S2 is as follows: S2.1. Lift the workpiece vertically, place the lower outer diameter of the large end of the workpiece on a motorized roller, and support the lower outer diameter of the small end with a cylindrical support. After the workpiece is aligned, lean it against the bent plate on both sides of the large end. At the same time, place a pressure plate on the bent plate to press the outer diameter of the large end of the workpiece tightly. S2.2. Place a square box and a fixed bent plate in the middle of the large end of the workpiece. After adjusting the height, use a pull rod and channel steel to assist in tightening the workpiece. When tightening, the channel steel is located near the horizontal center line of the workpiece to ensure stability at the center of gravity. The clamping and fixing of the workpiece in the above manner ensures that the stability and rigidity of the workpiece during processing are optimal, and at the same time facilitates adjustment of the workpiece in conjunction with subsequent processes, indirectly improving the processing quality.

[0011] As a preferred solution, the specific process of step S3 is as follows: S3.1. Use a rough boring tool to rough bore each hole in the lower 1 / 3 area of the workpiece, expanding the pre-cut bottom hole to about φA-50~60mm; replace the fine boring tool and machine each light hole in this area to the finished size; S3.2. Loosen the fixing assembly and use the overhead crane and electric rollers to adjust the workpiece rotation so that the unprocessed area is located below the workpiece. After adjustment, use the inner hole of the small end as a reference for alignment and coordinate setting. Use the method in step S3.1 to process the bottom hole in the remaining 1 / 3 area to the finished size. S3.3. After two adjustments, the processing is completed, and the workpiece is placed flat. The actual passability of each hole is checked using a test sample column to complete the processing. Taking into account the overall size of the workpiece, most machine tools cannot complete the processing in one time, and the 1 / 3 area below the workpiece is the most stable and has the best rigidity. Therefore, the processing process of subsequent holes is optimized, and a regional and step-by-step processing method is adopted. Each hole in the 1 / 3 area below the workpiece is processed in a single step. After the processing is completed, the overhead crane and electric roller are used to adjust the rotation of the workpiece so that the unprocessed area is located below the workpiece. After adjustment, the inner hole of the small end is used as the reference to align and open the coordinates, and then the holes in the 1 / 3 area below the workpiece are processed again until the holes in all areas are processed.

[0012] As a preferred solution, in step S3, the rough boring tool used is composed of 3 to 4 layers of blades, with 5 blades evenly distributed in each circle, and its outer diameter size is φA-50~60mm, and its minimum processing size is φA-140~150mm; the fine boring tool used is composed of 2 layers of blades, with 6 blades evenly distributed in each circle, and its outer diameter size is φA, with the first layer size being φA-30~40mm, and both layers participate in cutting. This solution processes each hole by designing a set of boring tools. Using this set of tools, each hole can be directly rough-bored and fine-bored, which is highly efficient. The efficiency of processing a single hole using this set of tools is more than 5 times that of the traditional interpolation milling method. When in use, multi-directional and multi-blade cutting is carried out simultaneously in layers, and the radial force is uniform during processing, which is not easy to vibrate the tool. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the drawings required for use in the embodiments or the description of the prior art. Obviously, the drawings described below are only some embodiments of the invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0014] Figure 1 It is a three-dimensional schematic diagram of a cone section for a rotary kiln in the prior art; Figure 2 It is a cross-sectional schematic diagram of a cone section for a rotary kiln; Figure 3 This is a schematic diagram of the clamping of the workpiece to be processed in the present invention; Figure 4 A front view of the rough boring tool used in the present invention; Figure 5 A side view of the rough boring tool used in the present invention; Figure 6 It is a front view of the fine boring tool used in the present invention; Figure 7 It is a side view of the fine boring tool used in the present invention.

[0015] Figure numerals: 1. workpiece to be processed, 2. fixed bending plate, 3. electric roller, 4. cylindrical support, 5. pull rod. DETAILED DESCRIPTION

[0016] The present invention is described in detail below by way of exemplary embodiments. However, it should be understood that elements, structures, and features in one embodiment may also be beneficially combined in other embodiments without further description.

[0017] It should be noted that, unless otherwise defined, the technical or scientific terms used herein shall have the ordinary meanings understood by persons having ordinary skills in the field to which the invention belongs; the words “one”, “an” or “the” and the like used in the patent application specification and claims of the present invention do not express quantitative limitations, but rather indicate the presence of at least one; the words “include” or “comprise” and the like indicate that the elements or objects preceding “include” or “comprises” include the elements or objects listed after “include” or “comprises” and their equivalents, but do not exclude other elements or objects having the same function; Example 1 An efficient machining method for dense hole systems of large tapered parts, the steps are as follows: Step 1: Pre-cut the bottom holes at each hole before processing: (1) First, draw the neutral plane projection of each hole in the expanded state of the steel plate, and use the projection size offset 30mm inward as the template size to draw the gas cutting template; (2) After cutting and welding, first mark the position lines of each hole on the blank, then align the gas cutting template with each hole position and place it, and finally use the gas cutting equipment perpendicular to the inner cone surface of the workpiece to pre-cut the bottom holes of each hole; to ensure the size of the pre-cut holes, each hole needs to be cut perpendicular to the cone angle during pre-cutting. After cutting the holes, use the template to control the minimum size of the cut bottom holes to ensure that the subsequent processing volume is as small as possible; Step 2: Place the cone section upright and fix it: (1) Prepare the electric rollers, square boxes and bending plates in advance, and place the fixtures in the approximate position with the outer cone of the workpiece facing the spindle of the machine tool; (2) Combination Figure 3 Detailed description: The workpiece 1 to be processed is lifted vertically, and the lower part of the outer circle of the large end of the workpiece is placed upright on the motorized roller 3, and the lower part of the outer circle of the small end is supported by a cylindrical support 4. After the workpiece is adjusted, it is placed on the left and right sides of the large end against the bending plate 2, and at the same time, a pressure plate is placed on the bending plate 2 to press the outer circle surface of the large end of the workpiece; (3) Place the square box and the bent plate in the middle of the large end of the workpiece. After adjusting the height, use the tie rod 5 and the channel steel to assist in tightening the workpiece. One end of the tie rod 5 is fixed on the bent plate 2. When tightening, the channel steel is located near the horizontal center line of the workpiece to ensure stability at the center of gravity. Step 3: Use rough boring tool and fine boring tool for processing: (1) Use a rough boring tool to perform rough boring on each hole in the lower 1 / 3 area of the workpiece, expand the pre-cut bottom hole to about φA-50~60mm, and eliminate the hardened layer formed by gas cutting; (2) Replace the fine boring tool and machine each hole in the rough boring area to the finished size.

[0018] (3) Adjustment: After the lower 1 / 3 is processed, loosen the pressure plates, channel steels and tie rods, and use the overhead crane and electric rollers to adjust the workpiece so that the unprocessed area is located below the workpiece. After adjustment, use the inner hole of the small end as the reference to align and open the coordinates, and process the inner hole of the other 1 / 3 area to the finished product size; (4) After adjusting twice, the processing of all area holes is completed. After unloading, the workpiece is placed flat and the actual passability of each hole is checked using the inspection sample column to complete the processing.

[0019] Example 2 An efficient machining method for dense hole systems of large tapered parts, the steps are as follows: Step 1: Pre-cut the bottom holes at each hole before processing: (1) First, draw the neutral plane projection of each hole in the expanded state of the steel plate, and use the projection size offset 40mm inward as the template size to draw the gas cutting template; (2) After cutting and welding, first mark the position lines of each hole on the blank, then align the gas cutting template with each hole position and place it, and finally use the gas cutting equipment perpendicular to the inner cone surface of the workpiece to pre-cut the bottom holes of each hole; to ensure the size of the pre-cut holes, each hole needs to be cut perpendicular to the cone angle during pre-cutting. After cutting the holes, use the template to control the minimum size of the cut bottom holes to ensure that the subsequent processing volume is as small as possible; Step 2: Place the cone section upright and fix it: (1) Prepare the electric rollers, square boxes and bending plates in advance, and place the fixtures in the approximate position with the outer cone of the workpiece facing the spindle of the machine tool; (2) Lift the workpiece 1 to be processed vertically, place the lower part of the outer circle of the large end of the workpiece on the electric roller 3, and support the lower part of the outer circle of the small end with a cylindrical support 4. After the workpiece is adjusted, it rests on the left and right sides of the large end against the bending plate 2, and at the same time, a pressure plate is placed on the bending plate 2 to press the outer circle surface of the large end of the workpiece; (3) Place the square box and the bent plate in the middle of the large end of the workpiece. After adjusting the height, use the tie rod 5 and the channel steel to assist in tightening the workpiece. One end of the tie rod 5 is fixed on the bent plate 2. When tightening, the channel steel is located near the horizontal center line of the workpiece to ensure stability at the center of gravity. Step 3: Use rough boring tool and fine boring tool for processing: (1) Use a rough boring tool to perform rough boring on each hole in the lower 1 / 2 area of the workpiece, expand the pre-cut bottom hole to about φA-50~60mm, and eliminate the hardened layer formed by gas cutting; (2) Replace the fine boring tool and machine each hole in the rough boring area to the finished size.

[0020] (3) Adjustment: Loosen the pressure plates, channel steels and pull rods, and use the overhead crane and electric rollers to adjust the rotation of the workpiece so that the unprocessed area is located below the workpiece. After adjustment, use the inner hole of the small end as the reference to align and open the coordinates, and process the inner holes in the remaining 1 / 2 area to the finished product size. Then, lay the workpiece flat and use the inspection sample column to check the actual passability of each hole to complete the processing.

[0021] The efficient processing technology for dense hole systems of large conical parts proposed in this invention has been applied to the batch processing and production of our company's products, improving the production efficiency of the products, reducing production costs, and shortening the production cycle. It can be seen that this process method is a relatively novel and practical processing method.

[0022] In the above embodiment, if Figure 4-5 As shown in the figure, the rough boring tool used is composed of 3 to 4 layers of blades, with 5 blades evenly distributed in each circle. In order to fully eliminate the gas-cut hard layer, its outer diameter is φA-50~60mm; in order to prevent pre-cutting size errors, its minimum processing size is φA-140~150mm, and it is generally not involved in cutting; Figure 6-7As shown, the fine boring tool consists of two layers of blades, with 6 blades evenly distributed in each circle. The outer diameter size is φA, and the size of the first layer is φA-30~40mm. The two layers participate in cutting together, optimizing the tool force situation and thus improving the processing surface quality.

[0023] In this embodiment, a set of boring tools is designed to process each hole. Using this set of tools, each hole can be directly rough-bored and fine-bored with high efficiency. The efficiency of using this set of tools to process a single hole is more than 5 times that of the traditional interpolation milling method. When used simultaneously, multi-directional and multi-blade cutting are performed in layers at the same time, and the radial force is uniform during processing, and the tool is not prone to vibration.

[0024] The parts not described in detail in the above embodiments are prior art.

[0025] It should be noted that although the various steps of the present invention are described through the above embodiments, the present invention may also have other various embodiments. Without departing from the spirit and scope of the present invention, it is obvious that those skilled in the art may make various corresponding changes and modifications to the present invention, and such changes and modifications shall fall within the scope of protection of the appended claims and their equivalents.

Claims

1. An efficient machining method for dense hole systems of large conical parts, wherein the hole size machined on the conical surface is set to φAmm, characterized in that: The steps include: S1. First, draw the neutral plane projection of each hole in the expanded state of the steel plate, and use the projection size offset inward by X as the template size. If X ≥ 30 mm, draw the gas cutting template. Then mark the position lines of each hole on the workpiece to be processed, align the gas cutting template with each hole position, and use the gas cutting equipment perpendicular to the inner cone surface of the workpiece to pre-cut the bottom hole of each hole; S2, placing the large end of the workpiece processed in step S1 on the motorized roller, supporting the small end, and then clamping and fixing the workpiece using a fixing assembly; S3. Use a rough boring tool to perform rough boring on the holes in the lower 1 / 3-1 / 2 area of the workpiece, and expand the pre-cut bottom hole to about φA-50~60mm; replace the fine boring tool and process the light holes in the rough boring area to the finished size; Then loosen the fixing components, use the overhead crane and electric rollers to adjust the rotation of the workpiece so that the unprocessed area is located below the workpiece. After adjustment, use the inner hole of the small end as a reference to align and open the coordinates, and use the same method to process the bottom holes in the other 1 / 3-1 / 2 area to the finished product size; continue to adjust the workpiece until the processing of holes in all areas is completed.

2. The method for efficiently machining dense hole systems of large tapered parts according to claim 1, characterized in that: In step S1, the projection size is offset inward by 30 mm as the template size.

3. The high-efficiency machining method for dense hole systems of large tapered parts according to claim 1, characterized in that: In step S2, the card installation process is as follows: S2.

1. Lift the workpiece vertically, place the lower outer diameter of the large end of the workpiece on a motorized roller, and support the lower outer diameter of the small end with a cylindrical support. After the workpiece is aligned, lean it against the bent plate on both sides of the large end. At the same time, place a pressure plate on the bent plate to press the outer diameter of the large end of the workpiece tightly. S2.

2. Place the square box and fixed bent plate in the middle of the large end of the workpiece. After adjusting the height, use the pull rod and channel steel to assist in tightening the workpiece. When tightening, the channel steel is located near the horizontal center line of the workpiece to ensure stability at the center of gravity.

4. The method for efficiently machining dense hole systems of large tapered parts according to claim 1, characterized in that: The specific process of step S3 is as follows: S3.

1. Use a rough boring tool to rough bore each hole in the lower 1 / 3 area of the workpiece, expanding the pre-cut bottom hole to about φA-50~60mm; replace the fine boring tool and machine each light hole in this area to the finished size; S3.

2. Loosen the fixing assembly and use the overhead crane and electric rollers to adjust the workpiece rotation so that the unprocessed area is located below the workpiece. After adjustment, use the inner hole of the small end as a reference for alignment and coordinate setting. Use the method in step S3.1 to process the bottom hole in the remaining 1 / 3 area to the finished size. S3.

3. After adjusting twice, the processing is completed, and the workpiece is placed flat. The actual passability of each hole is checked using a test sample column to complete the processing.

5. The high-efficiency machining method for dense hole systems of large tapered parts according to claim 1, characterized in that: In step S3, the rough boring tool used is composed of 3 to 4 layers of blades, with 5 blades evenly distributed in each circle, the outer diameter of which is φA-50~60mm, and the minimum processing size is φA-140~150mm.

6. The high-efficiency machining method for dense hole systems of large tapered parts according to claim 1, characterized in that: In step S3, the fine boring tool used is composed of two layers of blades, with 6 blades evenly distributed in each circle, and its outer diameter size is φA. The size of the first layer is φA-30~40mm, and the two layers participate in cutting together.

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