Efficient machining method for small-diameter metal thin-wall spherical crown part

Abstract

The invention discloses an efficient machining method for a small-diameter metal thin-wall spherical crown part, which is characterized in that products with all sizes are machined by adopting a small number of dies and a small specification of plate spinning blanks through reasonably designing the sizes of a spinning core die and a blank and matching spinning process parameters. On the premise that the machining precision of the product is guaranteed, the machining efficiency of the product is improved, and the machining period and cost are reduced.

Description

Technical Field

[0001] The invention belongs to the technical field of plastic forming processing, and in particular relates to a high-efficiency processing method for a small-diameter metal thin-walled spherical crown. Background Art

[0002] As a key part of a product in the aerospace field, the metal thin-walled spherical crown is used in large quantities and has high precision requirements. The initial method for processing this part was to directly use forging machining. The raw material utilization rate of a single spherical crown was less than 3%, and the product was repeatedly turned over between machining and heat treatment processes. Xi'an Aerospace Power Machinery Co., Ltd. proposed a process method for manufacturing thin-walled spherical crown parts based on modulated sheet metal spinning in its invention with patent number CN112275878 A. The core of the process is to pre-strengthen and temper the 30CrMnSiA steel slab before spinning to make its hardness HRC23~30. After the sheet metal is pre-formed by spinning, it is machined to remove the excess part. However, the diameter of the small end of the product processed by this invention is Φ300~Φ1000mm. In actual processing, a plate blank of one size can only be processed into a thin-walled spherical crown of one size. It is necessary to prepare corresponding spinning plate blanks and spinning molds for products of different sizes. The product corresponds to the plate blank and the spinning mold one by one. After processing each size of product, it is necessary to disassemble and install the next mold again, and re-align it, which increases the processing time by at least 40 minutes, and the efficiency is low. Xi'an Xiangyang Aerospace Materials Co., Ltd. proposed a production and manufacturing method for thin-walled double spherical reinforcements for flexible joints in its invention with patent number 202211367354.O. The core of this method is to optimize the machining fixtures from forgings to products and improve the utilization rate of fixtures. However, rough machining, semi-finishing, finishing and multiple intermediate heat treatments are required from forgings to products. The processing efficiency is low and the utilization rate of raw materials is low.

[0003] In summary, when processing thin-walled spherical crown parts with a large end diameter of ≤Φ300mm by the above two methods, there will be many types of molds and blank sizes; low processing efficiency and low raw material utilization. The present invention proposes to use 30CrMnSiA steel plate with a hardness requirement of HRC33-38, and through reasonable design of the spinning core mold and blank size, a small number of molds are used to process two or more products of one size of plate blank, and the best processing technology and processing flow are designed for the production and manufacturing of products. Summary of the invention

[0004] In order to overcome the shortcomings of the prior art, the present invention provides an efficient processing method for small-diameter metal thin-walled spherical crown parts, which can achieve the use of a small number of molds and a small number of specifications of plate spinning blanks to process all sizes of products by reasonably designing the spinning core mold and blank size and matching the spinning process parameters. The number of mold changes is reduced, and the processing efficiency of the product is improved while ensuring the product processing accuracy, and the processing cycle and cost are reduced.

[0005] The technical solution adopted by the present invention to solve the technical problem is as follows:

[0006] Step 1: Design and process the spinning core mold, inspection fixture and sheet blank according to the product size;

[0007] Step 2: Install the spinning core mold, spinning wheel and tail top on the spinning machine.

[0008] Step 3: Install the spinning blank: Put the spinning blank on the spinning core mold. When the tail top is pressed tightly, there is no interference between the spinning point of the spinning wheel and the tail top;

[0009] Step 4: Spinning the sheet blank;

[0010] Step 5: Heat treat the supination ball crown to eliminate internal stress;

[0011] Step 6: Machining the semi-finished ball crown after heat treatment to remove the allowance in the height and thickness directions and process it into the finished size; by adjusting the upper allowance and the lower allowance, two or more sizes of products can be machined out of the spun semi-finished ball crown with one size of plate blank.

[0012] Preferably, in step 1, the diameter of the large end of the product is ≤Φ300mm, the wall thickness is ≤2.0mm, the material is 30CrMnSiA, the hardness of the plate blank is required to be HRC33-38, the thickness is 8-13mm, and the thinning rate of the plate blank is not more than 50%; the effective height dimension of the spun semi-finished spherical crown has a reserved margin of more than 15mm above and below the product height, and the thickness dimension has a reserved margin of more than 1.0mm on one side based on the product thickness; the effective height of the core mold is greater than the effective height of the spun semi-finished product, and the gap from the starting point to the root and the spun product is uniformly transitioned from 0mm to 1.0-2.0mm; the outer surface and height of the inspection fixture are consistent with the inner surface and height of the spun semi-finished spherical crown.

[0013] Preferably, in step 2, the circular runout of the spinning core mold in the upper, middle and lower sections is detected to be no more than 0.05; a synchronous spinning method is adopted, the roundness of the spinning wheel is R15-R25, the axis of the spinning wheel and the axis of the core mold form a certain angle, and shear spinning occurs during the spinning process to form a curved generatrix rotating body component.

[0014] Preferably, in step 4, spinning is carried out in two passes, and the total thinning rate is not greater than 50%; the semi-finished spherical crown is formed by spinning; when the wall thickness of the upper, middle and lower sections is tested, it is not less than the thickness with a margin; the gap between the large end of the workpiece and the core mold is not greater than 1.0-2.0 mm, and the gap between the bottom end of the inspection fixture and the semi-finished spherical crown is not greater than 0.5 mm.

[0015] A computer program enables a computer to execute the above-mentioned efficient processing method.

[0016] An electronic device comprises: a processor and a memory; the memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the electronic device executes the above-mentioned efficient processing method.

[0017] A computer-readable storage medium stores a computer program, which implements the above-mentioned efficient processing method when executed by a processor.

[0018] A chip includes: a processor for calling and running a computer program from a memory, so that a device equipped with the chip executes the above-mentioned efficient processing method.

[0019] A computer program product comprises a computer storage medium storing a computer program, wherein the computer program comprises instructions executable by at least one processor, and the above-mentioned efficient processing method is implemented when the instructions are executed by the at least one processor.

[0020] The beneficial effects of the present invention are as follows:

[0021] The efficient processing method for thin-walled spherical crown parts with a large end diameter of ≤Φ300mm provided by the present invention designs a plate blank according to the product size, and processes it into a semi-finished spherical crown part through spinning. The plate blank of the same size can be processed into at least two metal thin-walled spherical crown parts after spinning, thereby reducing the number of molds and blank sizes required for processing a series of metal thin-walled spherical crown parts, reducing mold replacement, and effectively improving the processing efficiency of the product's spinning process, achieving the purpose of improving quality and increasing efficiency while ensuring product precision requirements. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] Figure 1 A product diagram of an embodiment of the present invention;

[0023] Figure 2 The semi-finished spherical crown piece after spinning in the embodiment of the present invention;

[0024] Figure 3 This is a comparison diagram of 1# and 2# products and semi-finished spherical crown parts in the embodiment of the present invention. DETAILED DESCRIPTION

[0025] The present invention is further described below in conjunction with the accompanying drawings and embodiments.

[0026] The present invention proposes an efficient processing method for metal thin-walled spherical crown parts with a large end diameter of ≤Φ300mm. By reasonably designing the spinning core mold and the blank size and matching the spinning process parameters, it is possible to use a small number of molds and a small number of specifications of plate spinning blanks to process all sizes of products. The number of mold replacements is reduced, and under the premise of ensuring product processing accuracy, the processing efficiency of the product is improved, and the processing cycle and cost are reduced.

[0027] To achieve the above object, the processing method of the present invention comprises the following steps:

[0028] Step 1: Design and process the spinning core mold, inspection fixture and sheet blank according to the product size.

[0029] The large end diameter of the product is ≤Φ300mm, the wall thickness is ≤2.0mm, the material is 30CrMnSiA, the hardness of the plate blank is required to be HRC33~38, the thickness is recommended to be 8~13mm, and the thinning rate of the plate blank is not more than 50%. The effective height dimension of the semi-finished spherical crown after spinning has a reserve margin of more than 15mm above and below the product height, and the thickness dimension has a reserve margin of more than 1.0mm on one side based on the product thickness. The effective height of the core mold is greater than the effective height of the semi-finished product after spinning, and the gap between the starting point and the root and the spinning product transitions evenly from 0mm to 1.0~2.0mm. The outer surface and height of the inspection fixture are consistent with the inner surface and height of the semi-finished spherical crown after spinning. The plate blank is calculated based on the blank of the variable wall thickness curved mother line.

[0030] Step 2: Install the spinning core mold, spinning wheel and tail top on the spinning machine.

[0031] The circular runout of the spinning mandrel in the upper, middle and lower sections is not greater than 0.05. The synchronous spinning method is adopted, the roundness of the spinning wheel is R15~R25, and the axis of the spinning wheel and the axis of the mandrel form a certain angle to ensure that shear spinning mainly occurs during the spinning process to form a curved generatrix rotating body component.

[0032] Step 3: Install the spinning blank.

[0033] Put the spinning blank on the spinning core mold. When the tail top is pressed tightly, there is no interference between the spinning point of the spinning wheel and the tail top.

[0034] Step 4: Spinning the sheet blank.

[0035] Spinning is carried out in two passes, and the total thinning rate is not more than 50%. Spinning forms semi-finished spherical crown parts. When testing the wall thickness of the upper, middle and lower sections, they are not less than the thickness with margin. The gap between the large end of the workpiece and the core mold is not more than 1.0-2.0mm, and the gap between the bottom end of the inspection fixture and the semi-finished spherical crown part is not more than 0.5mm.

[0036] Step 5: Heat treat the supination ball crown to eliminate internal stress.

[0037] Step 6: Machining the semi-finished ball crown after heat treatment, removing the allowance in the height direction and thickness direction, and processing it into the finished product size. By adjusting the upper allowance and the lower allowance, two or more sizes of products can be machined from the semi-finished ball crown of the same sheet blank size. At this point, the processing of small-diameter thin-walled ball crowns is completed.

[0038] Example:

[0039] The product of the thin-walled spherical crown processed in this embodiment is as follows Figure 1 As shown, there are 10 products of different sizes, with a wall thickness of (δ±0.1) mm, a height of H, a roundness of no more than 0.2-0.4 mm, a large end diameter of 250-300 mm, and a spherical radius R determined according to design requirements. The specific process steps are as follows:

[0040] Step 1: Design and process the spinning core mold, inspection fixture and sheet blank according to the product size.

[0041] The blank material is 30CrMnSiA; the hardness of the plate blank is required to be HRC33~38, and the thickness is 10mm. The effective height dimension of the semi-finished spherical crown after spinning has a reserve margin of 15mm above and below the product height, and the thickness dimension has a reserve margin of 1.8mm on one side based on the product thickness. The effective height of the core mold is greater than the effective height of the semi-finished product after spinning, and the gap between the starting part and the root and the spinning product transitions evenly from 0mm to 1.6mm. The outer surface and height of the inspection fixture are consistent with the inner surface and height of the semi-finished spherical crown after spinning. The plate blank is calculated based on the variable wall thickness curved mother line blank, and there are 5 sizes of blanks.

[0042] Step 2: Install the spinning core mold, spinning wheel and tail top on the spinning machine.

[0043] The circular runout of the spinning core mold in the upper, middle and lower sections is not greater than 0.05. The synchronous spinning method is adopted, the roundness of the spinning wheel is R25, and the axis of the spinning wheel is 27° with the axis of the core mold, ensuring that shear spinning mainly occurs during the spinning process to form a curved generatrix rotating body component.

[0044] Step three: install the spinning blank.

[0045] Put the spinning blank on the spinning core mold. When the tail top is pressed tightly, there is no interference between the spinning point of the spinning wheel and the tail top.

[0046] Step 4: Spinning the sheet blank.

[0047] Spinning is carried out in two passes, with a total thinning rate of 46%. Spinning forms semi-finished spherical crown parts. When testing the wall thickness of the upper, middle and lower sections, they are all no less than (δ+3.6) mm. The gap between the large end of the workpiece and the core mold is no more than 1.6 mm, and the gap between the bottom end of the inspection fixture and the semi-finished spherical crown part is no more than 1.0 mm.

[0048] Step five, heat-treating the supination ball crown to eliminate internal stress.

[0049] Step 6: Machining the semi-finished ball crown after heat treatment, removing the allowance in the height direction and thickness direction, and processing it into the finished product size. By adjusting the upper allowance and the lower allowance, two or more sizes of products can be machined from the semi-finished ball crown of one sheet blank size. At this point, the processing of small-diameter metal thin-walled ball crowns is completed.

Claims

1. An efficient processing method for a small-diameter metal thin-walled spherical crown, characterized in that: The steps include: Step 1: Design and process the spinning core mold, inspection fixture and sheet blank according to the product size; Step 2: Install the spinning core mold, spinning wheel and tail top on the spinning machine; Step 3: Install the spinning blank; Put the spinning blank on the spinning core mold, and when the tail top is pressed tightly, there is no interference between the spinning point of the spinning wheel and the tail top; Step 4: Spinning the sheet blank; Step 5: Heat treat the supination ball crown to eliminate internal stress; Step 6: Machining the semi-finished ball crown after heat treatment to remove the allowance in the height and thickness directions and process it into the finished size; by adjusting the upper allowance and the lower allowance, two or more sizes of products can be machined out of the spun semi-finished ball crown with one size of plate blank.

2. The high-efficiency processing method of a small-diameter metal thin-walled spherical crown according to claim 1 is characterized in that: In the step 1, the large end diameter of the product is ≤Φ300mm, the wall thickness is ≤2.0mm, the material is 30CrMnSiA, the hardness of the plate blank is required to be HRC33-38, the thickness is 8-13mm, and the thinning rate of the plate blank is not more than 50%; the effective height dimension of the spun semi-finished ball crown part has a reserved margin of more than 15mm above and below the product height, and the thickness dimension has a reserved margin of more than 1.0mm on one side based on the product thickness; the effective height of the core mold is greater than the effective height of the spun semi-finished product, and the gap between the starting point to the root and the spun product is uniformly transitioned from 0mm to 1.0-2.0mm; the outer surface and height of the inspection fixture are consistent with the inner surface and height of the spun semi-finished ball crown part.

3. The high-efficiency processing method of a small-diameter metal thin-walled spherical crown according to claim 2 is characterized in that: In step 2, the circular runout of the spinning core mold in the upper, middle and lower sections is detected to be no greater than 0.05; a synchronous spinning method is adopted, the roundness of the spinning wheel is R15-R25, the axis of the spinning wheel and the axis of the core mold form a certain angle, and shear spinning occurs during the spinning process to form a curved generatrix rotating body component.

4. The high-efficiency processing method of a small-diameter metal thin-walled spherical crown according to claim 3 is characterized in that: In step 4, spinning is carried out in two passes, and the total thinning rate is not more than 50%; the semi-finished spherical crown is formed by spinning; when the wall thickness of the upper, middle and lower sections is tested, they are not less than the thickness with a margin; the gap between the large end of the workpiece and the core mold is not more than 1.0-2.0 mm, and the gap between the bottom end of the inspection fixture and the semi-finished spherical crown is not more than 0.5 mm.

5. A computer program, characterized in that The computer program enables a computer to execute the method according to any one of claims 1 to 4.

6. An electronic device, characterized in that: include: Processor and memory; The memory is used to store a computer program, and the processor is used to execute the computer program stored in the memory, so that the electronic device executes the method as claimed in any one of claims 1 to 4.

7. A computer-readable storage medium having a computer program stored thereon, characterized in that: When the computer program is executed by a processor, the method according to any one of claims 1 to 4 is implemented.

8. A chip, characterized in that: include: A processor, configured to call and run a computer program from a memory, so that a device equipped with the chip executes a method as claimed in any one of claims 1 to 4.

9. A computer program product, characterized in that The computer program product comprises a computer storage medium storing a computer program, wherein the computer program comprises instructions executable by at least one processor, and when the instructions are executed by the at least one processor, the method according to any one of claims 1 to 4 is implemented.

Images