CN110744262B

CN110744262B - Machining method for large complex thin-wall cabin part

Info

Publication number: CN110744262B
Application number: CN201911079461.1A
Authority: CN
Inventors: 耿立博; 李中华
Original assignee: Beijing Xinghang Electromechanical Equipment Co Ltd
Current assignee: Beijing Xinghang Electromechanical Equipment Co Ltd
Priority date: 2019-11-07
Filing date: 2019-11-07
Publication date: 2021-03-05
Anticipated expiration: 2039-11-07
Also published as: CN110744262A

Abstract

The invention provides a method for processing a large-scale complex thin-wall cabin-like part, which is characterized in that aiming at the complex structure of the part, a laser scanning method is utilized to determine that a part blank has enough processing allowance and obtain a machining reference; aiming at the problem that part of features cannot be processed, a method for assembling a steel bushing to form an equipment mounting surface is provided; aiming at the problems of difficult clamping and reference transmission and large part processing deformation caused by large appearance and thin wall thickness of parts, the turning and boring clamping tool is designed. The invention can ensure that all the characteristics of the complex parts are processed in place, and meets the use requirements; the rigidity of the thin-wall part can be improved and clamping deformation can be reduced by clamping the thin-wall part by using the tool; the clamping of large-scale thin-walled parts and the reference transmission among different processes can be realized.

Description

Machining method for large complex thin-wall cabin part

Technical Field

The invention belongs to the technical field of part machining, and particularly relates to a method for machining large-scale complex thin-wall cabin parts.

Background

The large complex thin-wall cabin section part is made of ZL114A, the diameter of an outer circle is phi 470mm, the length is 1312mm, the outer surface has a plurality of sunken parts, deep cavities and a plurality of window features, the front end face of the cabin section is of an open structure, the rear end face of the cabin section is of a closed structure, the wall thickness of the part is 2.5 +/-0.5 mm, and four equipment mounting bosses in the inner cavity of the cabin section cannot be machined. Therefore, in order to realize clamping and reference transmission of the parts, reduce the processing deformation of the parts and process all the characteristics in place, a processing method of the large-scale complex thin-wall cabin part is required.

Disclosure of Invention

Technical problem to be solved

The invention provides a method for machining large complex thin-wall cabin parts, and aims to solve the technical problem of how to machine the large complex thin-wall cabin parts.

(II) technical scheme

In order to solve the technical problem, the invention provides a method for machining large complex thin-wall cabin-section parts, which comprises the following steps:

s1, determining the machining allowance of the part blank, and obtaining a machining reference:

s2, clamping the cabin section part through a turning and boring clamping tool, firstly machining the excircle of the part by using a lathe, and then machining the window and the sinking characteristic on the excircle by using a numerical control boring machine;

and S3, assembling the steel bushing to form a device mounting surface.

Further, step S1 specifically includes: and carrying out laser scanning on the inner surface and the outer surface of the casting blank to obtain casting scanning data, comparing the scanning data with the theoretical model allowance, and determining a numerical control machining reference surface.

Further, in step S2, the lathe clamping fixture in the boring clamping fixture includes a front flange, a rear flange, a first pull rod, a positioning pin, and a clamping positioning plate; during clamping, firstly, the cabin section part, the front flange plate and the rear flange plate are assembled by using the positioning pins, and the front flange plate and the rear flange plate are ensured to be coaxial with the part; then the first pull rod penetrates through a reserved clamping hole of the part, two ends of the first pull rod are in threaded connection with the front flange plate and the rear flange plate, and the front flange plate, the rear flange plate and the part are fixed by the first pull rod; clamping and aligning the excircle and the end face of the positioning disc by using four jaws of a lathe; and finally, assembling the parts on a clamping positioning disc.

Further, in step S2, the tool for clamping the numerical control boring machine in the boring and clamping tool includes a chassis, a cover plate, a limit pin, and a second pull rod; during clamping, firstly fixing the chassis on an A shaft of a machine tool, and aligning the excircle of the chassis; and then inserting a plurality of limit pins into corresponding pin holes of the chassis, determining the positions of the cabin part and the chassis when the cabin part and the chassis are installed by using the limit pins, and fixing the part, the chassis and the cover plate by using the second pull rod.

Further, step S3 specifically includes: and respectively processing a counter bore and a threaded hole on the corresponding outer surface of the boss of the part shell, then screwing in the steel bushing, and forming an equipment mounting surface by the end surface of the steel bushing after the steel bushing is mounted in place.

(III) advantageous effects

Aiming at the complex structure of the large complex thin-wall cabin part, the laser scanning method is utilized to determine that a part blank has enough machining allowance and obtain a machining reference; aiming at the problem that part of features cannot be processed, a method for assembling a steel bushing to form an equipment mounting surface is provided; aiming at the problems of difficult clamping and reference transmission and large part processing deformation caused by large appearance and thin wall thickness of parts, the turning and boring clamping tool is designed.

The invention can ensure that all the characteristics of the complex parts are processed in place, and meets the use requirements; the rigidity of the thin-wall part can be improved and clamping deformation can be reduced by clamping the thin-wall part by using the tool; the clamping of large-scale thin-walled parts and the reference transmission among different processes can be realized.

Drawings

FIG. 1 is a schematic structural view of a tool for lathe clamping in an embodiment of the invention;

FIG. 2 is a schematic structural diagram of the tool for clamping the numerical control boring machine in the embodiment of the invention.

Detailed Description

In order to make the objects, contents and advantages of the present invention clearer, the following detailed description of the embodiments of the present invention will be made in conjunction with the accompanying drawings and examples.

The embodiment provides a method for machining a large complex thin-wall cabin part, which specifically comprises the following steps:

s1, determining the machining allowance of the part blank, and obtaining a machining reference: the large-scale complex thin-wall cabin part has a complex structure, in order to ensure enough machining allowance, the inner surface and the outer surface of a casting blank are subjected to laser scanning to obtain casting scanning data, then the scanning data and the theoretical model allowance are compared through special software, and under the condition that the allowance is enough, a reference surface is led out to UG software in an stp format for numerical control machining.

S2, clamping the cabin section part through the special boring and clamping tool, firstly machining the excircle of the part by using a lathe, and then machining the window, sinking and other characteristics on the excircle by using a numerical control boring machine:

(1) the lathe clamping tool is shown in figure 1 and comprises a front flange plate 1, a rear flange plate 2, a first pull rod 3, a positioning pin 4 and a clamping positioning plate 5. When clamping, the cabin section part, the front flange plate and the rear flange plate are assembled by the positioning pin 4, and the front flange plate and the rear flange plate are coaxial with the part. Then, the first pull rod 3 penetrates through a reserved clamping hole of the part, two ends of the first pull rod 3 are in threaded connection with the front flange plate and the rear flange plate, and the front flange plate, the rear flange plate and the part are fixed by the first pull rod 3. Meanwhile, the outer circle and the end face of the positioning disc 5 are clamped and aligned by four jaws of a lathe. Finally, the parts are assembled to the clamping positioning plate 5.

(2) The tool for clamping the numerical control boring machine is shown in fig. 2 and comprises a chassis 6, a cover plate 7, a limiting pin 8 and a second pull rod 9. During clamping, the chassis 6 is fixed on the shaft A of the machine tool, and the excircle of the chassis 6 is aligned. Then, three limit pins 8 are inserted into corresponding pin holes of the chassis 6, the position of the cabin part when the cabin part and the chassis 6 are installed is determined by the limit pins 6, and the part, the chassis 6 and the cover plate 7 are fixed by the second pull rod 9.

S3, assembling the steel bushing to form an equipment mounting surface: the bosses at four positions of the inner cavity of the large-sized complex thin-wall cabin part cannot be machined, so that counter bores and threaded holes are respectively machined at the corresponding outer surfaces of the bosses at four positions of the shell, then the steel bushing is screwed in, and after the steel bushing is installed in place, the end face of the steel bushing forms an equipment installation face.

The above description is only a preferred embodiment of the present invention, and it should be noted that, for those skilled in the art, several modifications and variations can be made without departing from the technical principle of the present invention, and these modifications and variations should also be regarded as the protection scope of the present invention.

Claims

1. A machining method for large complex thin-wall cabin-like part is characterized by comprising the following steps:

s1, determining the blank machining allowance of the cabin section part, and obtaining a machining reference:

s2, clamping the cabin section part blank through a turning and boring clamping tool, firstly machining the outer circle of the cabin section part blank through a lathe, and then machining a window and sinking features on the outer circle through a numerical control boring machine; wherein the content of the first and second substances,

the lathe clamping tool of the boring clamping tool comprises a front flange plate, a rear flange plate, a first pull rod, a positioning pin and a clamping positioning plate; during clamping, assembling the cabin section part blank with the front flange plate and the rear flange plate by using the positioning pins, and ensuring that the front flange plate, the rear flange plate and the cabin section part blank are coaxial; then a first pull rod penetrates through a reserved clamping hole of the cabin section part blank, two ends of the first pull rod are in threaded connection with the front flange plate and the rear flange plate, and the front flange plate, the rear flange plate and the cabin section part blank are fixed by the first pull rod; clamping and aligning the excircle and the end face of the positioning disc by using four jaws of a lathe; finally, assembling the cabin section part blank on a clamping positioning disc;

the tool for clamping the numerical control boring machine of the turning-boring clamping tool comprises a chassis, a cover plate, a limiting pin and a second pull rod; during clamping, firstly fixing the chassis on an A shaft of a machine tool, and aligning the excircle of the chassis; then inserting a plurality of limit pins into corresponding pin holes of the chassis, determining the positions of the cabin part blank and the chassis when the cabin part blank and the chassis are installed by using the limit pins, and fixing the cabin part blank, the chassis and the cover plate by using a second pull rod;

s3, assembling the steel bushing to form an equipment mounting surface, and specifically comprises the following steps: and respectively processing counter bores and threaded holes on the corresponding outer surfaces of the bosses of the cabin section part shell, screwing in the steel bushings, and forming equipment mounting surfaces by the end surfaces of the steel bushings after the steel bushings are mounted in place.

2. The processing method according to claim 1, wherein the step S1 specifically includes: and the cabin section part blank is a casting blank, the inner surface and the outer surface of the casting blank are subjected to laser scanning to obtain scanning data of the casting blank, the scanning data and the theoretical model allowance are compared, and a numerical control machining reference plane is determined.