CN111922637A - Manufacturing process for ensuring coaxiality of shaft sleeve - Google Patents

Manufacturing process for ensuring coaxiality of shaft sleeve Download PDF

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Publication number
CN111922637A
CN111922637A CN202010704869.XA CN202010704869A CN111922637A CN 111922637 A CN111922637 A CN 111922637A CN 202010704869 A CN202010704869 A CN 202010704869A CN 111922637 A CN111922637 A CN 111922637A
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China
Prior art keywords
shaft sleeve
turning
side wall
blank
outer side
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CN202010704869.XA
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CN111922637B (en
Inventor
邹一峰
顾宇顺
陆忠泉
孙志华
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Zhejiang Changsheng Sliding Bearings Co Ltd
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Zhejiang Changsheng Sliding Bearings Co Ltd
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Publication of CN111922637A publication Critical patent/CN111922637A/en
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B23MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23PMETAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
    • B23P15/00Making specific metal objects by operations not covered by a single other subclass or a group in this subclass

Abstract

A manufacturing process for ensuring the coaxiality of a shaft sleeve comprises the following steps: providing a shaft sleeve blank; clamping one end of the outer side wall of the shaft sleeve blank and turning the inner side wall and the outer side wall of the bearing blank at the same time, wherein the turning of the outer side wall of the bearing blank is a first turning and a certain margin is reserved, and the axial length of the first turning of the outer side wall of the shaft sleeve blank is greater than half of the axial length of the shaft sleeve blank and less than the whole shaft sleeve length of the shaft sleeve blank; clamping the turned outer side wall of the shaft sleeve blank to perform secondary turning on the non-turned outer side wall of the bearing blank and leaving a certain margin; and providing a centerless grinding machine, and grinding the turned blank of the shaft sleeve to ensure that the precision of the outer side wall of the shaft sleeve meets the precision requirement so as to manufacture the shaft sleeve with high coaxiality. The manufacturing process can not damage the coaxiality due to the centerless grinding, so that the coaxiality of the shaft sleeve blank can be ensured in the whole grinding process, the coaxiality of the shaft sleeve can be further ensured, and the coaxiality precision is improved.

Description

Manufacturing process for ensuring coaxiality of shaft sleeve
Technical Field
The invention belongs to the technical field of shaft sleeve manufacturing, and particularly relates to a manufacturing process for ensuring the coaxiality of a shaft sleeve.
Background
The shaft sleeve is a cylindrical mechanical part sleeved on the rotating shaft and is a component of the sliding bearing. Typically, the sleeve is an interference fit with the bearing seat and a clearance fit with the shaft.
For some high-precision tools or equipment, the coaxiality requirement of the shaft sleeve is generally high, but is difficult to guarantee, because the shaft sleeve is used, and multiple dimensional accuracies are involved in the using process, such as the dimensional accuracy of a hole of a bearing seat, the dimensional accuracy of the coaxiality of the inner side wall and the outer side wall of the shaft sleeve, the dimensional accuracy of the shaft, and the like. Accuracy is therefore guaranteed if these dimensional errors accumulate. In particular, the coaxiality of the inner and outer side walls of the shaft sleeve is difficult to be ensured at the same time, so that the precision is difficult to be improved as a whole.
In order to solve the above problems, the current method is to use a turning machine to clamp the sleeve blank, and then simultaneously turn the inner and outer side walls of the sleeve blank to ensure the coaxiality of the inner and outer side walls. And finally, cutting off the part of the shaft sleeve blank which is not turned, namely the part clamped by the turning machine. Although the coaxiality of the inner wall and the outer wall of the shaft sleeve can be ensured, thermal stress is formed on the shaft sleeve during cutting, and the thermal stress can become a fatal defect of the shaft sleeve during later use, such as stress crack, end face tensile crack and the like, which can cause hidden troubles during use.
Disclosure of Invention
In view of the above, the present invention provides a manufacturing process for ensuring the coaxiality of the shaft sleeve, which can solve the above problems.
A manufacturing process for ensuring the coaxiality of a shaft sleeve comprises the following steps:
s1: providing a shaft sleeve blank;
s2: clamping one end of the outer side wall of the shaft sleeve blank, turning the inner side wall and the outer side wall of the bearing blank at the same time, enabling the turning precision of the inner side wall of the shaft sleeve blank to meet the precision requirement, turning the outer side wall of the bearing blank for the first turning and reserving a certain allowance, wherein the axial length of the first turning of the outer side wall of the shaft sleeve blank is greater than half of the axial length of the shaft sleeve blank and less than the whole shaft sleeve length of the shaft sleeve blank;
s3: clamping the turned outer side wall of the shaft sleeve blank to perform secondary turning on the non-turned outer side wall of the bearing blank and reserving a certain allowance, wherein the allowance reserved by the secondary turning is smaller than the allowance reserved by the primary turning;
s4: and providing a centerless grinding machine, and grinding the turned blank of the shaft sleeve to ensure that the precision of the outer side wall of the shaft sleeve meets the precision requirement so as to manufacture the shaft sleeve with high coaxiality.
Further, the turning accuracy requirement of the shaft sleeve is that the cylindricity is less than 0.01.
Further, in step S2, the axial length of the turning of the outer side wall of the sleeve blank is two thirds of the total axial length of the sleeve blank.
Further, a salt bath heat treatment step is further included before step S3 and step S4.
Further, the allowance left in the first turning of the outer side wall of the shaft sleeve blank is 0.10-0.20 mm, and the allowance left in the second turning of the outer side wall of the shaft sleeve blank is 0.08-0.15 mm.
Further, the allowance left in the first turning of the outer side wall of the shaft sleeve blank is 0.15mm, and the allowance left in the second turning of the outer side wall of the shaft sleeve blank is 0.1 mm.
Further, the allowance left in the first turning of the outer side wall of the shaft sleeve blank is larger than the allowance left in the second turning by 0.05 mm.
Further, the axial length of the shaft sleeve blank meets the requirement of precision.
Compared with the prior art, the manufacturing process for ensuring the coaxiality of the shaft sleeve provided by the invention firstly clamps one end of the shaft sleeve blank, and then simultaneously turns the inner side wall and the outer side wall of the shaft sleeve blank, so that the coaxiality of the inner side wall and the outer side wall of the shaft sleeve blank turned at the second time can be ensured, and a certain margin is reserved when the outer side wall is turned at the first time. Then clamping the machined part, turning the unprocessed part for the second time, wherein a certain margin is reserved during the turning for the second time, but the margin reserved during the turning for the second time is smaller than the margin reserved during the turning for the first time, and the axial length of the turning for the second time is smaller than the axial length of the turning for the first time, then putting the shaft sleeve blank turned for the second time into a centerless grinder for grinding, wherein the margin reserved during the turning for the second time is smaller than the margin reserved during the turning for the first time, and the axial length of the turning for the second time is smaller than the axial length of the turning for the first time, so that the part of the shaft sleeve blank turned for the first time in the whole grinding process is a reference surface and a processing surface, and meanwhile, the concentricity cannot be damaged due to the centerless grinding, the coaxiality of the shaft sleeve blank can be ensured in the whole grinding process, and further the coaxiality of the shaft sleeve can be ensured, the coaxial precision is improved.
Drawings
Fig. 1 is a flow chart of a manufacturing process for ensuring the coaxiality of a shaft sleeve provided by the invention.
Fig. 2 is a schematic structural diagram of the bearing blank machined in step S2 in the flow chart of fig. 1.
Fig. 3 is a schematic structural diagram of the bearing blank processed in step S3 in the flow chart of fig. 1.
Fig. 4 is a schematic structural diagram of the process of step S4 in the flowchart of fig. 1 when a centerless grinder is used for machining.
Detailed Description
Specific examples of the present invention will be described in further detail below. It should be understood that the description herein of embodiments of the invention is not intended to limit the scope of the invention.
Fig. 1 is a flowchart of a manufacturing process for ensuring the coaxiality of a shaft sleeve according to the present invention. The manufacturing process for ensuring the coaxiality of the shaft sleeve comprises the following steps:
s1: providing a sleeve blank 10;
s2: clamping one end of the outer side wall of the shaft sleeve blank 10, turning the inner side wall and the outer side wall of the bearing blank 10 at the same time, enabling the turning precision of the inner side wall of the shaft sleeve blank to meet the precision requirement, turning the outer side wall of the bearing blank 10 for the first turning and reserving a certain allowance, wherein the axial length of the first turning of the outer side wall of the shaft sleeve blank 10 is greater than half of the axial length of the shaft sleeve blank 10 and less than the total shaft sleeve length of the shaft sleeve blank 10;
s3: clamping the turned outer side wall of the shaft sleeve blank 10 to perform secondary turning on the non-turned outer side wall of the bearing blank 10 and reserving a certain allowance, wherein the allowance reserved by the secondary turning is smaller than the allowance reserved by the primary turning;
s4: and providing a centerless grinder 20, and grinding the turned shaft sleeve blank 10 to enable the precision of the outer side wall of the shaft sleeve to meet the precision requirement so as to manufacture the shaft sleeve with high coaxiality.
In step S1, the sleeve blank 10 may be a workpiece whose axial length has been determined or whose axial length meets the accuracy requirement. The blank 10 may be a cylindrical structure made of steel, copper, etc.
In step S2, the positions of the triangles represent the positions at which the bearing blank 10 is clamped, as shown in fig. 2. The clamp for clamping the shaft sleeve blank 10 should be a clamp on a lathe, and the tool for turning the inner and outer side walls of the shaft sleeve blank 10 is also arranged on the lathe, and the precision of the tool is determined by the lathe itself, so that the precision of the lathe itself should be guaranteed, and details are not repeated herein. When the sleeve blank 10 is clamped on a lathe, the clamped length should be less than one third of the total axial length of the sleeve blank 10. Then, the lathe is started, and the inner side wall and the outer side wall of the shaft sleeve blank 10 are turned by the tool for turning the inner side wall and the outer side wall. When the inner side wall is turned, the accuracy during turning should be ensured, that is, the accuracy of the inner side wall of the shaft sleeve blank 10 has already reached the accuracy requirement, such as flatness, smoothness and the like, through the turning of the inner side wall. In the turning of the outer side wall, since one end of the sleeve blank 10 is clamped, in step S2, the axial length of the turning of the outer side wall is smaller than the total axial length of the sleeve blank 10, but the axial length of the turning of the outer side wall is greater than half of the total axial length of the sleeve blank 10. Specifically, in step S2, the axial length of the turning of the outer side wall of the sleeve blank 10 is two thirds of the total axial length of the sleeve blank 10. For the purpose of distinction, the turning of the outer side wall of the sleeve blank 10 in step S2 is defined as the first turning. In the present embodiment, the turning precision of the sleeve blank 10 is required to be less than 0.01 by turning the inner and outer side walls, that is, the coaxiality of the first turned part and the inner side wall is already up to the requirement. The first cutting whiskers have a certain margin for grinding in a subsequent process. It should be noted that the margin is relative to the turning accuracy, i.e., the turning accuracy is not achieved by leaving a margin. The allowance left in the first turning of the outer side wall of the bearing blank 10 may be 0.10mm to 0.20mm, and in the present embodiment, the allowance left in the first turning of the outer side wall of the sleeve blank 10 is 0.15 mm.
In step S3, the position of the triangle is also the position representing the position at which the bearing blank 10 is clamped, as shown in fig. 3. The outer side wall of the shaft sleeve blank 10 which has been turned is clamped by the fixture of the lathe again, that is, the outer side wall of the shaft sleeve blank 10 which has been turned for the first time is clamped, the outer side wall of the shaft sleeve blank 10 which has not been turned is turned by the tool, and the turning in the step S3 is defined as the second turning. This second turning must also be done with some margin for grinding in subsequent processes. The allowance left in the first turning of the outer side wall of the shaft sleeve blank 10 is larger than the allowance left in the second turning by 0.05 mm. And the allowance left in the second turning of the outer side wall of the shaft sleeve blank 10 is 0.08 mm-0.15 mm. In this embodiment, the margin left in the second turning of the outer side wall of the sleeve blank 10 is 0.1 mm. Since two thirds of the total axial length of the sleeve blank 10 are turned in the first turning, one third of the total axial length of the sleeve blank 10 is turned in the second turning.
After this step S3, a salt bath heat treatment, i.e. a heat quenching of the workpiece with a salt in the molten state, may also be performed, which is per se prior art and will not be described in detail here. The salt bath heat treatment has the advantages of large comprehensive heat exchange coefficient, high workpiece heating speed, close contact between the workpiece and bath liquid, uniform heating and small deformation. The bath furnace has large heat capacity and small heating temperature fluctuation, is easy to maintain a neutral state, and realizes non-oxidation and non-decarburization heating. Through the heat treatment, the hardness of the whole turned shaft sleeve blank 10 is increased.
In step S4, as shown in fig. 4, a centerless grinder, which is a prior art technique in itself, is first used and will not be described in detail. The centerless grinding machine is a grinding machine which does not need to adopt the axis positioning of a workpiece for grinding, and mainly comprises a grinding wheel, an adjusting wheel and a workpiece support. The shaft sleeve blank 10 after the second turning is mounted on a grinding wheel and a working bracket, so that the shaft sleeve blank 10 is ground by the grinding of the grinding wheel. Because two thirds of the total axial length of the shaft sleeve blank 10 is turned during the first turning, and the allowance left during the first turning is larger than the allowance left during the second turning, when the shaft sleeve blank 10 after the second turning is placed on the centerless grinding machine, the part of the shaft sleeve blank 10 during the first turning is in contact with the grinding wheel, and the part of the shaft sleeve blank 10 during the second turning is overhead, so that the part during the first turning is the reference surface and the processing surface. And because the precision of the coaxiality of the part and the inner side wall of the shaft sleeve blank 10 during the first turning already meets the requirement, and the coaxiality cannot be damaged during the grinding of the centerless grinder, the parameters such as the flatness and the smoothness of the inner side wall and the outer side wall of the shaft sleeve can meet the requirement through the grinding of the centerless grinder, and the coaxiality of the inner side wall and the outer side wall of the shaft sleeve blank 10 is also ensured.
Compared with the prior art, the manufacturing process for ensuring the coaxiality of the shaft sleeve provided by the invention firstly clamps one end of the shaft sleeve blank 10, and then simultaneously turns the inner side wall and the outer side wall of the shaft sleeve blank 10, so that the coaxiality of the inner side wall and the outer side wall of the shaft sleeve blank 10 turned at the time can be ensured, and a certain margin is reserved when the outer side wall is turned for the first time. Then clamping the machined part, turning the unprocessed part for the second time, wherein a certain margin is reserved during the turning for the second time, but the margin reserved during the turning for the second time is smaller than the margin reserved during the turning for the first time, and the axial length of the turning for the second time is smaller than the axial length of the turning for the first time, then putting the shaft sleeve blank turned for the second time into a centerless grinder for grinding, wherein the margin reserved during the turning for the second time is smaller than the margin reserved during the turning for the first time, and the axial length of the turning for the second time is smaller than the axial length of the turning for the first time, so that the part of the shaft sleeve blank turned for the first time in the whole grinding process is a reference surface and a processing surface, and meanwhile, the concentricity cannot be damaged due to the centerless grinding, the coaxiality of the shaft sleeve blank can be ensured in the whole grinding process, and further the coaxiality of the shaft sleeve can be ensured, the coaxial precision is improved.
The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the scope of the present invention, and any modifications, equivalents or improvements that are within the spirit of the present invention are intended to be covered by the following claims.

Claims (8)

1. A manufacturing process for ensuring the coaxiality of a shaft sleeve comprises the following steps:
s1: providing a shaft sleeve blank;
s2: clamping one end of the outer side wall of the shaft sleeve blank, turning the inner side wall and the outer side wall of the bearing blank at the same time, enabling the turning precision of the inner side wall of the shaft sleeve blank to meet the precision requirement, turning the outer side wall of the bearing blank for the first turning and reserving a certain allowance, wherein the axial length of the first turning of the outer side wall of the shaft sleeve blank is greater than half of the axial length of the shaft sleeve blank and less than the whole shaft sleeve length of the shaft sleeve blank;
s3: clamping the turned outer side wall of the shaft sleeve blank to perform secondary turning on the non-turned outer side wall of the bearing blank and reserving a certain allowance, wherein the allowance reserved by the secondary turning is smaller than the allowance reserved by the primary turning;
s4: and providing a centerless grinding machine, and grinding the turned blank of the shaft sleeve to ensure that the precision of the outer side wall of the shaft sleeve meets the precision requirement so as to manufacture the shaft sleeve with high coaxiality.
2. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 1, wherein: the cylindricity in the turning accuracy requirement of axle sleeve is less than 0.01.
3. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 1, wherein: in step S2, the axial length of the turning of the outer side wall of the sleeve blank is two thirds of the total axial length of the sleeve blank.
4. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 1, wherein: a salt bath heat treatment step is further included before step S3 and step S4.
5. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 1, wherein: the allowance left in the first turning of the outer side wall of the shaft sleeve blank is 0.10-0.20 mm, and the allowance left in the second turning of the outer side wall of the shaft sleeve blank is 0.08-0.15 mm.
6. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 5, wherein: the allowance left in the first turning of the outer side wall of the shaft sleeve blank is 0.15mm, and the allowance left in the second turning of the outer side wall of the shaft sleeve blank is 0.1 mm.
7. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 5, wherein: and the allowance left in the first turning of the outer side wall of the shaft sleeve blank is larger than the allowance left in the second turning by 0.05 mm.
8. The manufacturing process for ensuring the coaxiality of the shaft sleeve as claimed in claim 1, wherein: the axial length of the shaft sleeve blank meets the requirement of precision.
CN202010704869.XA 2020-07-21 2020-07-21 Manufacturing process for ensuring coaxiality of shaft sleeve Active CN111922637B (en)

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CN111922637B CN111922637B (en) 2022-04-08

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Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19753111A1 (en) * 1997-11-29 1999-06-10 Federal Mogul Wiesbaden Gmbh Bearing bush with a central collar and its use and manufacturing process
JP2011247408A (en) * 2010-04-27 2011-12-08 Minebea Co Ltd Non-lubricated sliding bearing having self-lubricating liner
CN104384825A (en) * 2014-08-01 2015-03-04 中国人民解放军第五七一九工厂 Machining deformation control method of bushing thin-wall part
CN106425337A (en) * 2016-12-28 2017-02-22 贵州虹轴轴承有限公司 Bearing machining process
CN108673072A (en) * 2018-08-01 2018-10-19 重庆通用工业(集团)有限责任公司 Face-hardened large thin-wall stainless steel axle sleeve manufacturing process
CN108788650A (en) * 2018-06-28 2018-11-13 安庆银亿轴承有限公司 A kind of processing technology of bearing holder (housing, cover)
CN109773416A (en) * 2017-11-15 2019-05-21 中设精工制造江苏有限公司 A kind of high lead bearing shell manufacturing process of marine main engine thin-walled
CN109955035A (en) * 2017-12-25 2019-07-02 丹阳市延陵镇度越五金厂 A kind of axle sleeve processing method

Patent Citations (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
DE19753111A1 (en) * 1997-11-29 1999-06-10 Federal Mogul Wiesbaden Gmbh Bearing bush with a central collar and its use and manufacturing process
JP2011247408A (en) * 2010-04-27 2011-12-08 Minebea Co Ltd Non-lubricated sliding bearing having self-lubricating liner
CN104384825A (en) * 2014-08-01 2015-03-04 中国人民解放军第五七一九工厂 Machining deformation control method of bushing thin-wall part
CN106425337A (en) * 2016-12-28 2017-02-22 贵州虹轴轴承有限公司 Bearing machining process
CN109773416A (en) * 2017-11-15 2019-05-21 中设精工制造江苏有限公司 A kind of high lead bearing shell manufacturing process of marine main engine thin-walled
CN109955035A (en) * 2017-12-25 2019-07-02 丹阳市延陵镇度越五金厂 A kind of axle sleeve processing method
CN108788650A (en) * 2018-06-28 2018-11-13 安庆银亿轴承有限公司 A kind of processing technology of bearing holder (housing, cover)
CN108673072A (en) * 2018-08-01 2018-10-19 重庆通用工业(集团)有限责任公司 Face-hardened large thin-wall stainless steel axle sleeve manufacturing process

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