A method for processing a large-size hole

Abstract

The application discloses a kind of big size hole's sleeve processing method, comprising the following steps: the processing contour line of the hole to be processed is drawn on the surface of workpiece;Electromagnetic chuck of magnetic chuck type core fixing device is adsorbed on the inner wall of processing area and non-processing area by lifting appliance;Workpiece is installed;Processing of the hole to be processed is carried out according to preset steps;The core is taken away by magnetic chuck type core fixing device.The application keeps adsorbing and fixing the core by magnetic chuck type core fixing device, and the core does not fall off at the moment of processing completion, which ensures the safety of processing;By adjusting the installation position and magnetic force of electromagnetic chuck, it can be suitable for different materials and sizes of the hole to be processed;By clockwise and counterclockwise swing processing, the core can be balanced as much as possible on both sides, which not only can improve the processing precision, but also can reduce safety hazards.

Description

Technical Field

[0001] This invention relates to the field of machining technology, and in particular to a method for machining large-size holes using a bushing. Background Technology

[0002] In fields such as tunnel boring machines, shipbuilding, and engineering facilities, drilling holes in large parts is a crucial production process. Traditional methods for machining large holes involve drilling and boring, resulting in significant waste of raw materials as chips. To meet market demands, a nesting process can be used to machine large holes, removing a portion of the material from the workpiece for reuse. This not only improves material utilization but also reduces labor intensity and increases production efficiency, proving highly effective in practice. However, because the core material produced by nesting is often not secured, it can detach immediately after machining, leading to tool damage and workpiece injury. To secure the core material during nesting, specialized tooling is required. However, conventional tooling fixtures, with their fixing points on the worktable, not only interfere with the nesting process but also lack versatility, making them unsuitable for different workpiece sizes. Summary of the Invention

[0003] The technical problem this invention aims to solve is to address the shortcomings of existing technologies by providing a method for machining large-size holes. This method not only allows for the adsorption and fixation of the workpiece core during the machining process and its timely removal after machining, but also allows for adjustment of the installation position and adsorption strength to accommodate workpieces of different sizes. Furthermore, the operation is convenient and quick, and the adsorption tool is reusable. The method for machining large-size holes provided in this application adopts the following technical solution:

[0004] A method for machining large-size holes includes the following steps:

[0005] S1. Based on the size of the hole to be machined in the workpiece, a machining outline is drawn on the surface of the workpiece to divide the workpiece into a machining area and a non-machining area around it.

[0006] S2, according to the size of the workpiece and the hole to be processed, install the electromagnetic chuck of the magnetic chuck core fixing device on the fixing hole at a suitable position on the fixed support, and drive the magnetic chuck core fixing device to move through the lifting tool, and open all the electromagnetic chucks so that one electromagnetic chuck of the magnetic chuck core fixing device is adsorbed on the inner wall of the processing area, and the remaining electromagnetic chucks are adsorbed on the inner wall of the non-processing area.

[0007] S3, the magnetic chuck-type core fixing device is moved together with the workpiece by the lifting device, the workpiece is lifted to the preset position of the processing machine tool, and the workpiece is clamped and aligned;

[0008] S4, using a hole-opening device to process the hole to be processed along the processing contour line according to preset steps, so as to separate the core material from the workpiece body;

[0009] S5, turn off the electromagnetic chuck adsorbed in the non-processing area, and move the magnetic chuck-type core fixing device and the separated core together through the lifting tool to move the core to the dropping area.

[0010] S6, adjust the magnetic suction switch to turn off the electromagnetic chuck adsorbed in the processing area, so that the material core falls into the material dropping area.

[0011] As a preferred technical solution, the magnetic chuck type core fixing device includes a fixed support and at least two electromagnetic chucks. The electromagnetic chucks are fixedly connected through the fixed support, and each electromagnetic chuck is equipped with a magnetic switch.

[0012] As a preferred technical solution, the fixed support is provided with several rows of fixing holes, and the electromagnetic chuck is installed on the fixed support through the fixing holes. The fixing hole position of the electromagnetic chuck is adapted to the overall size of the hole to be processed.

[0013] As a preferred technical solution, the magnetic attraction force of the electromagnetic chuck adsorbed in the processing area can be adjusted according to the thickness, size, and material of the hole to be processed, and the magnetic attraction force F satisfies the following formula:

[0014] F=K×δ×S

[0015] In the formula, K is the magnetic force coefficient related to the workpiece material, which is obtained by laboratory measurement; δ is the thickness of the hole to be processed; and S is the area of ​​the hole to be processed.

[0016] As a preferred technical solution, in step S4, the preset step is: using a machining drill bit to open a machining tool inlet hole at a preset point on the machining contour line, inserting the machining tool from the inlet hole, and machining the hole to be machined along the machining contour line according to the preset steps.

[0017] As a preferred technical solution, the infeed hole is opened on the machining contour line and is located at the intersection of the machining contour line and the vertical line of the center of gravity of the material core.

[0018] As a preferred technical solution, in step S5, the machining method of the hole to be machined is as follows: the machining tool is oscillating clockwise and counterclockwise several times along the machining contour line with the infeed hole as the center until the machining of the hole to be machined is completed.

[0019] As a preferred technical solution, the clockwise and counterclockwise oscillation machining method is as follows: the machining tool takes the infeed hole as the center and processes n° clockwise along the machining contour line, then processes 2n° counterclockwise and clockwise in sequence, and so on, until the machining of the hole to be processed is completed.

[0020] As a preferred technical solution, in step S2, when the size of the hole to be processed is very large, multiple magnetic chuck-type core fixing devices are used in combination to adsorb the workpiece.

[0021] As a preferred technical solution, the drill bit used for machining the feed hole is a U-shaped drill.

[0022] In summary, this application includes at least one of the following beneficial technical effects:

[0023] 1. This invention uses a lifting device to move a magnetic chuck-type core fixing device, which then attaches several electromagnetic chucks of the device to the workpiece's processing and non-processing areas. During the nesting process, the magnetic chuck-type core fixing device maintains its attachment to the core, ensuring that the core will not fall off immediately upon completion of processing and guaranteeing processing safety. After processing is completed, the lifting device moves the magnetic chuck-type core fixing device to remove the core promptly.

[0024] 2. By adjusting the magnetic switch, this invention can not only control the opening and closing of each electromagnetic chuck individually, but also adjust the magnetic force according to the material and size of the hole to be processed, so as to achieve stable adsorption of holes of different sizes and further improve safety.

[0025] 3. The magnetic chuck type core fixing device of the present invention has a number of rows of fixing holes on the fixing support. By adjusting the installation position of the magnetic chuck on the fixing support, it can be used to adsorb holes of different sizes to be processed, which facilitates subsequent nesting processing.

[0026] 4. In this invention, the infeed hole is opened on the machining contour line and positioned at the intersection of the machining contour line and the vertical line of the core's center of gravity. The machining process is then performed clockwise and counterclockwise several times along the machining contour line, centered on the infeed hole, until the hole to be machined is completed. This clockwise and counterclockwise oscillation process ensures that the core is subjected to relatively balanced force on both sides, preventing uneven force distribution that could affect machining accuracy and avoid core breakage or detachment from the workpiece, thus preventing safety hazards. By positioning the infeed hole at the intersection of the machining contour line and the vertical line of the core's center of gravity, the support provided by the workpiece to the core is reduced as the hole is machined to a certain extent, preventing breakage due to gravity and further improving the machining effect. Attached Figure Description

[0027] Figure 1This is a schematic diagram of the operation of a set of magnetic chuck-type core fixing devices of the present invention;

[0028] Figure 2 This is a schematic diagram of the operation of the multi-group magnetic chuck type core fixing device of the present invention.

[0029] Figure label:

[0030] 1-Workpiece, 11-Machining outline, 12-Machining area, 13-Non-Machining area;

[0031] 2-Magnetic chuck type core fixing device, 21-Electromagnetic chuck, 22-Fixing support, 23-Magnetic switch, 24-Fixing hole Detailed Implementation

[0032] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings and examples. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0033] It should be noted that, unless otherwise specified, the embodiments and features described in the present invention can be combined with each other.

[0034] A method for machining large-size holes, referring to Figure 1 and Figure 2 It includes the following methods and steps:

[0035] S1. Based on the size of the hole to be processed, a machining outline 11 is drawn on the surface of workpiece 1, dividing workpiece 1 into a machining area 12 and a non-machining area 13 around it. Before workpiece 1 is installed on the machine tool, according to the requirements of machining the core, a machining outline 11 is drawn on the surface of workpiece 1 based on the size and position of the hole to be processed. The area inside the machining outline 11 is the machining area 12, which facilitates the adsorption of the electromagnetic chuck 21 to fix and support the core to be processed. The area outside the machining outline 11 is the non-machining area 13, which facilitates the adsorption of the electromagnetic chuck 21 to achieve stable adsorption of the magnetic chuck-type core fixing device, facilitating subsequent processing and material removal.

[0036] S2, according to the size of the workpiece 1 and the hole to be processed, install the electromagnetic chuck 21 of the magnetic chuck core fixing device 2 on the fixing hole 24 at a suitable position on the fixing support 22, and move the magnetic chuck core fixing device 2 by the lifting tool to open all the electromagnetic chucks 21, so that one electromagnetic chuck 21 of the magnetic chuck core fixing device 2 is adsorbed on the inner wall of the processing area 12, and the remaining electromagnetic chucks 21 are adsorbed on the inner wall of the non-processing area 13.

[0037] like Figure 1and Figure 2 As shown, in some embodiments, the magnetic chuck-type core fixing device 2 includes a fixed support 22 and at least two electromagnetic chucks 21. One electromagnetic chuck 21 is attached to the inner wall of the processing area 12 to support and fix the core in the hole to be processed, preventing the core from falling off after processing. The other electromagnetic chucks 21 are attached to the inner wall of the non-processing area 13, so that the magnetic chuck-type core fixing device 2 is firmly fixed to the workpiece 1, providing better support for the core. The fixed support 22 is used to fix the electromagnetic chucks 21 together. The fixed support 22 is provided with several rows of fixing holes 24. The electromagnetic chucks 21 are installed on the fixed support 22 through the fixing holes 24. The electromagnetic chucks 21 can be installed in a suitable position according to the size of the workpiece 1 and the hole to be processed. This application can be applied to adsorb holes of different sizes to be processed, which is convenient for subsequent nesting processing. Each electromagnetic chuck 21 is equipped with a magnetic switch 23. The magnetic switch 23 can not only control the opening and closing of each electromagnetic chuck 21, but also adjust the magnetic force according to the size of the hole to be processed, so as to achieve stable adsorption of holes of different sizes and further improve safety.

[0038] The magnetic chuck-type core fixing device 2 is connected to the lifting device. By adjusting the magnetic switch 23, all electromagnetic chucks 21 are activated. The lifting device moves the magnetic chuck-type core fixing device 2, causing the electromagnetic chucks 21 to adhere to the relevant area, thus achieving a stable connection between the magnetic chuck-type core fixing device 2 and the workpiece 1, facilitating subsequent nesting processing. In this method, the magnetic chuck-type core fixing device 2 adheres to the inner wall of the workpiece 1, while the machining tool performs nesting processing on the outer wall of the workpiece 1. Therefore, the magnetic chuck-type core fixing device 2, while fixing the core, does not interfere with the nesting processing of the workpiece 1.

[0039] S3, the magnetic chuck-type core fixing device 2 is moved together with the workpiece 1 by the lifting device, and the workpiece 1 is hoisted to the preset position of the processing machine tool, and the workpiece 1 is clamped and aligned. By simultaneously activating the electromagnetic chuck 21 adsorbed in the processing area 12 and the electromagnetic chuck 21 adsorbed in the non-processing area 13, the workpiece 1 and the magnetic chuck-type core fixing device 2 are moved together. By clamping and aligning the workpiece 1, the accuracy of subsequent nesting processing can be improved.

[0040] S4, the hole to be processed is processed along the processing contour line 11 according to the preset steps using the hole-opening device, so that the core material is separated from the workpiece 1 body;

[0041] In some embodiments, the hole-opening device is a hole-opening tool, and the preset steps are: using a machining drill bit to open a machining tool inlet hole at a preset point on the machining contour line 11, inserting the machining tool from the inlet hole, and machining the hole to be machined along the machining contour line 11 according to the preset steps.

[0042] Preferably, the infeed hole is formed on the machining contour line 11 and is positioned symmetrically to the intersection point of the machining contour line 11 and the central axis of the magnetic chuck-type core fixing device 2. The machining method for the hole to be machined is as follows: the machining tool, with the infeed hole as the center, oscillates clockwise and counterclockwise along the machining contour line 11 several times until the machining of the hole is completed, as detailed below:

[0043] 1) Starting from the infeed hole, machine the tool clockwise along the machining contour line 11 to a position of about 30°, and then machine counterclockwise from the infeed hole to a position of about 60°;

[0044] 2) The machining tool moves clockwise about 60° along the machining contour line 11, to a position of about 90°, and then counterclockwise about 60°, to a position of about 120°;

[0045] 3) The machining tool moves clockwise about 60° along the machining contour line 11 to a position of about 150°, and then counterclockwise about 60° to a position of about 180°.

[0046] 4) The machining tool processes the remaining part clockwise along the machining contour line 11 to complete the machining of the hole to be machined.

[0047] This invention processes the hole by rotating clockwise and counterclockwise, which ensures that the core is subjected to balanced force on both sides, preventing the core from shaking and affecting processing accuracy due to uneven force. It also avoids the core breaking or falling off the workpiece, which could pose a safety hazard. By setting the infeed hole at the intersection of the processing contour line and the vertical line of the core's center of gravity, the invention prevents breakage due to gravity when the hole is processed to a certain extent, further improving the processing effect.

[0048] In some embodiments, the hole-opening device may also be configured as a flame cutting device; when machining a planar hole, the hole-opening device may also be configured as a spiral milling device.

[0049] S5, adjust the magnetic suction switch 23 to turn off the electromagnetic chuck 21 adsorbed in the non-processing area 13, and move the magnetic chuck type core fixing device 2 and the separated core together through the lifting tool to move the core to the dropping area.

[0050] After processing is completed, the electromagnetic chuck 21 adsorbed in the non-processing area 13 is turned off, which allows the magnetic chuck-type core fixing device 2 to be detached from the workpiece 1. Since the electromagnetic chuck 21 in the processing area 12 is still adsorbed on the core, the core is fixed together with the magnetic chuck-type core fixing device 2. The magnetic chuck-type core fixing device 2 and the separated core can be moved together by the lifting tool.

[0051] S6, adjust the magnetic switch 23 to turn off the electromagnetic chuck 21 adsorbed in the processing area 12, so that the material core falls into the material dropping area, and the material core in the material dropping area can be processed and reused.

[0052] In some embodiments, the magnetic attraction force of the electromagnetic chuck 21 adsorbed in the processing area 12 can be adjusted according to the thickness, size, and material of the hole to be processed, and the magnetic attraction force F satisfies the following formula:

[0053] F=K×δ×S

[0054] In the formula, K is the magnetic force coefficient related to the material of workpiece 1, which is obtained by laboratory measurement; δ is the thickness of the hole to be processed; and S is the area of ​​the hole to be processed.

[0055] For workpiece 1, the larger the area and the thicker the hole to be processed, the greater the gravity of the hole, requiring a relatively large magnetic force to fix the core during processing. However, if the magnetic force of the electromagnetic chuck 21 is too large, it will cause workpiece 1 to deform, affecting its performance; if the magnetic force of the electromagnetic chuck 21 is too small, the magnetic chuck-type core fixing device 2 cannot provide stable support for the core, thus failing to achieve good nesting and material handling effects. This invention obtains the magnetic force coefficient related to the material of workpiece 1 through experimental data and correlates the electromagnetic force with the thickness and area of ​​the hole to be processed. This allows for the provision of suitable electromagnetic force for holes of different materials, thicknesses, and areas. The magnetic force can then be adjusted to a suitable level by adjusting the magnetic switch 23. This application not only improves the applicability to different workpieces 1 but also provides better nesting effects.

[0056] As a preferred embodiment, when the hole to be processed is large, multiple magnetic chuck-type core fixing devices 2 can be used in combination to provide a sufficiently large magnetic force to attract and fix the workpiece 1. Figure 2 As shown in the figure, in one embodiment, when the size of the hole to be processed is very large, two magnetic chuck-type core fixing devices 2 are set in the upper half of the core and three magnetic chuck-type core fixing devices 2 are set in the lower half of the core. Through five sets of electromagnetic chucks 21, sufficient electromagnetic attraction is provided for the large core, realizing stable support for the large core and facilitating subsequent nesting processing and material removal.

[0057] In a preferred embodiment, a U-drill is used for machining the feed hole. When the wall thickness of the workpiece 1 is relatively thick, a milling cutter can be used for machining. When the wall thickness of the workpiece 1 is relatively thin, a grooving cutter can be used for machining.

[0058] This invention provides a method for machining large-size holes by inserting a core material, which can fix the core material during and after the machining process, and can quickly and accurately separate the core material. It can also be flexibly applied to workpieces of different materials and sizes. Therefore, compared with the existing machining processes, the method for machining large-size holes provided by this invention has obvious technical advantages.

[0059] The above are merely preferred embodiments of the present invention and are not intended to limit the implementation methods and protection scope of the present invention. Those skilled in the art should recognize that any equivalent substitutions and obvious changes made based on the content of this specification should be included within the protection scope of the present invention.

Claims

1. A method for machining large-size holes using a bushing, characterized in that, Includes the following steps: S1. Based on the size of the hole to be machined in the workpiece, a machining outline is drawn on the surface of the workpiece to divide the workpiece into a machining area and a non-machining area around it. S2, according to the size of the workpiece and the hole to be processed, install the electromagnetic chuck of the magnetic chuck core fixing device on the fixing hole at a suitable position on the fixed support, and drive the magnetic chuck core fixing device to move through the lifting tool, and open all the electromagnetic chucks so that one electromagnetic chuck of the magnetic chuck core fixing device is adsorbed on the inner wall of the processing area, and the remaining electromagnetic chucks are adsorbed on the inner wall of the non-processing area. S3, the magnetic chuck-type core fixing device is moved together with the workpiece by the lifting device, the workpiece is lifted to the preset position of the processing machine tool, and the workpiece is clamped and aligned; S4, using a hole-opening device to process the hole to be processed along the processing contour line according to preset steps, so as to separate the core material from the workpiece body; S5, turn off the electromagnetic chuck adsorbed in the non-processing area, and move the magnetic chuck-type core fixing device and the separated core together through the lifting tool to move the core to the dropping area. S6, Adjust the magnetic switch to turn off the electromagnetic chuck adsorbed in the processing area, so that the material core falls into the material dropping area; In step S4, the preset step is as follows: a machining drill bit is used to open a machining tool inlet hole at a preset point on the machining contour line, the machining tool is inserted from the inlet hole, and the hole to be machined is machined along the machining contour line according to the preset step; The infeed hole is located at the intersection of the machining contour line and the vertical line of the center of gravity of the material core. In step S5, the machining method of the hole to be machined is as follows: the machining tool is oscillating clockwise and counterclockwise several times along the machining contour line with the infeed hole as the center until the machining of the hole to be machined is completed. The specific method of clockwise and counterclockwise oscillation machining is as follows: the machining tool takes the infeed hole as the center and processes n° clockwise along the machining contour line, then processes 2n° counterclockwise and clockwise in sequence, and so on, until the machining of the hole to be processed is completed.

2. The method for machining large-size holes according to claim 1, characterized in that, The magnetic chuck type core fixing device includes a fixed support and at least two electromagnetic chucks. The electromagnetic chucks are fixedly connected through the fixed support, and each electromagnetic chuck is equipped with a magnetic switch.

3. The method for machining large-size holes according to claim 2, characterized in that, The fixed support is provided with several rows of fixing holes. The electromagnetic chuck is installed on the fixed support through the fixing holes. The fixing hole position of the electromagnetic chuck is adapted to the overall size of the hole to be processed.

4. The method for machining large-size holes according to claim 3, characterized in that, The magnetic chuck adsorbed in the processing area has an adjustable magnetic force, which can be determined according to the thickness, size, and material of the hole to be processed. The magnetic force F satisfies the following formula: F=K×δ×S In the formula, K is the magnetic force coefficient related to the workpiece material, which is obtained by laboratory measurement; δ is the thickness of the hole to be processed; and S is the area of ​​the hole to be processed.

5. The method for machining large-size holes according to claim 1, characterized in that, In step S2, when the size of the hole to be processed is very large, multiple magnetic chuck-type core fixing devices are used in combination to adsorb the workpiece.

6. The method for machining large-size holes according to claim 1, characterized in that, The drill bit used for machining the feed hole is a U-shaped drill.

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