Auxiliary tool for erecting center frame for thin-wall shell with large length-diameter ratio

Abstract

The invention discloses an auxiliary tool for erecting a center frame for a large-length-diameter-ratio thin-wall shell. The auxiliary tool sequentially comprises an aluminum semicircular ring, a steel semicircular ring and an aluminum outer lining from inside to outside. The two aluminum semicircular rings surround the outer circle of the shell to form a first whole circle. The two steel semicircular rings surround the outer circle of the first full circle to form a second full circle; and the aluminum outer bushing surrounds the outer circle of the second full circle. The middle position of the shell with the large length-diameter ratio and the thin wall can be supported in an auxiliary mode, the vibration problem during turning of the middle of the shell is solved, and therefore turning of the middle of the thin-wall shell is achieved; and meanwhile, in the using process, the stress of the shell is uniform, and secondary deformation of the shell caused by the auxiliary tool for erecting the center frame for the thin-wall shell with the large length-diameter ratio can be minimized.

Description

Technical Field

[0001] The invention relates to the field of mechanical processing, and in particular to an auxiliary tooling for a center frame of a thin-wall shell with a large aspect ratio. Background Art

[0002] A thin-walled shell with a large aspect ratio is one of the important parts of a solid rocket engine. The shell has an aspect ratio of 12:1, with large outer diameters at both ends and small outer diameters in the middle. A turning structure is designed in the middle of the shell, and the coaxiality of the turning structure is required to be controlled within φ0.1. Conventional turning of the shell adopts the clamping method of "one clamp and one top" (one end is clamped by a four-jaw chuck and the other end is tightened by a tail top), but the rigidity is poor during turning in the middle, which will cause turning vibration and cannot meet the design and processing requirements of the middle structure. Common large aspect ratio parts in turning, such as crankshafts and transmission shafts, generally add center frame auxiliary support and follower frame auxiliary support on the basis of the "one clamp and one top" clamping method to enhance the stability of the workpiece during processing and avoid turning vibration and deformation. The center frame and follower frame auxiliary supports are rigid supports, requiring the supported position of the workpiece to be a finished surface and have good rigidity. However, the middle part of the shell has poor rigidity after spinning and heat treatment, and has irregular deformation. There is no machining allowance at the supporting position, and a finished surface cannot be formed. This results in the inability to directly use the center stand or follower rest for support during the shell turning process.

[0003] Therefore, a tool is needed that can assist in setting up a center frame to provide additional support when turning the middle structure of the shell. The tool needs to adapt to the irregular deformation of the outer circle of the shell itself, have sufficient rigidity to use the center frame to provide auxiliary support, and cannot cause further deformation of the shell. Summary of the invention

[0004] The technical problem solved by the present invention is: to overcome the deficiencies of the above-mentioned prior art and to provide a center frame auxiliary tooling for a thin-walled shell with a large aspect ratio, so as to meet the center frame auxiliary support requirements when turning the middle structure of the shell.

[0005] An auxiliary tooling for a center frame of a thin-walled shell with a large aspect ratio, which includes, from the inside to the outside, an aluminum semicircular ring, a steel semicircular ring, and an aluminum outer bushing;

[0006] There are two aluminum semicircular rings, which surround the outer circle of the shell to form a first full circle;

[0007] There are two steel semicircular rings, which surround the outer circle of the first full circle to form a second full circle;

[0008] The aluminum outer bushing surrounds the outer circle of the second full circle.

[0009] A kind of auxiliary tooling for erecting a center frame of a thin-walled shell with a large aspect ratio, wherein two aluminum bosses symmetrically arranged in upper and lower directions are arranged at one end of the outer circular surface of the aluminum semicircular ring, and the aluminum bosses are provided with radial threaded holes; except for the aluminum bosses, the rest of the aluminum semicircular ring is a thin-walled semicircular ring.

[0010] An auxiliary tooling for a center frame of a thin-walled shell with a large aspect ratio, wherein steel boss structures are arranged on the upper and lower outer sides of both ends of the steel semicircular ring, and a tightening threaded hole is arranged in the middle of the steel boss for connecting the steel semicircular ring;

[0011] The tightening threaded hole includes a through hole, a pin hole, and a radial step through hole;

[0012] The through hole is used to connect the two steel semicircular rings;

[0013] The pin holes include axial positioning pin holes and radial positioning pin holes, which are used to position the two steel semicircular rings. To ensure the docking accuracy of the two steel semicircular rings after disassembly and reassembly, the axial pin holes and the radial pin holes are processed after the two steel semicircular rings are assembled into a full circle.

[0014] The radial step through hole is used to connect the two steel semicircular rings and the two aluminum semicircular rings;

[0015] The steel semicircular ring is a thick-walled semicircular ring; the steel semicircular ring is provided with double rows of radially staggered and evenly distributed threaded holes for installing tightening bolts.

[0016] An auxiliary tooling for a center frame of a thin-walled shell with a large aspect ratio, wherein the aluminum outer bushing is an aluminum thick-walled ring, the aluminum outer bushing is a consumable, and the radial thickness is greater than 20 mm when in use.

[0017] An auxiliary tooling for a center frame of a thin-walled shell with a large aspect ratio, wherein the rotation axis of the first full circle coincides with the rotation axis of the shell; the rotation axis of the second full circle coincides with the rotation axis of the first full circle; the rotation axis of the aluminum outer bushing coincides with the rotation axis of the second full circle;

[0018] The assembly sequence from inside to outside is: the shell, the first full circle, the second full circle, and the aluminum outer bushing.

[0019] A center frame auxiliary tooling for a thin-walled shell with a large aspect ratio, wherein the inner circle of the first full circle is in direct contact with the shell by clearance fit; the inner circle of the second full circle is in clearance fit with the outer circle of the first full circle; and the inner circle of the aluminum outer bushing is in transition fit with the outer circle of the second full circle.

[0020] A center frame auxiliary tooling for a thin-walled shell with a large aspect ratio, wherein the steel semicircular ring and the aluminum semicircular ring are connected by screws; the two steel semicircular rings are positioned by radial positioning pins and axial positioning pins, and are fastened and connected by fastening bolts and fastening nuts.

[0021] An auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio, wherein the steel semicircular ring uses the tightening bolts to tighten the aluminum semicircular ring through the double-row radially staggered and evenly distributed threaded holes reserved on the thick-walled semicircular ring in the middle of the steel semicircular ring;

[0022] The aluminum semicircular ring can be locally deformed to adapt to the irregular deformation of the outer circle of the shell itself, and prevent the shell from being damaged by the tightening bolt.

[0023] An auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio, wherein preliminary correction of the second full circle rotation axis and the shell rotation axis is performed by adjusting the tightening bolts installed on the steel semicircular ring.

[0024] A kind of auxiliary tooling for mounting a center frame on a thin-walled shell with a large aspect ratio, wherein, after each installation of the aluminum outer bushing, the outer circle of the aluminum outer bushing needs to be completely turned to ensure that its rotation axis is coaxial with the rotation axis of the shell, so as to achieve precise correction of the rotation axis of the auxiliary tooling for mounting a center frame on a thin-walled shell with a large aspect ratio and the rotation axis of the thin-walled shell.

[0025] The advantages of the present invention compared with the prior art are:

[0026] (1) The present invention can adapt to the deformation of the outer circle of the shell itself, and the deformation of the shell is small when the large aspect ratio thin-walled shell with the center frame auxiliary tooling is used. The force on the shell is uniform during use, which can minimize the secondary deformation of the shell caused by the large aspect ratio thin-walled shell with the center frame auxiliary tooling itself.

[0027] (2) The present invention has high adjustment accuracy and strong adaptability. The auxiliary tooling for the large aspect ratio thin-walled shell and the center frame can be applied to shells in different deformation states. By adjusting the tightening bolts on the steel semicircular ring, the rotation axis of the auxiliary tooling for the large aspect ratio thin-walled shell and the center frame can be preliminarily corrected. By turning the outer circle of the aluminum outer bushing, the rotation axis of the auxiliary tooling for the large aspect ratio thin-walled shell and the center frame can be accurately corrected, so that the rotation axis of the auxiliary tooling for the large aspect ratio thin-walled shell and the center frame is highly coaxial with the rotation axis of the shell.

[0028] (3) The large aspect ratio thin-walled shell with center frame auxiliary tooling in the present invention has strong rigidity and is installed on the outer circle of the shell, thereby enhancing the rigidity of the shell and reducing turning vibration.

[0029] (4) The present invention has low use cost. For shells in different deformation states, the present invention only consumes the outermost aluminum outer bushing; the aluminum semi-circular ring and the steel semi-circular ring can be used continuously without replacement, which can effectively reduce the processing cost. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the technical solutions disclosed in the present invention, the following briefly introduces the drawings required to be used in some embodiments disclosed in the present invention. Obviously, the drawings described below are only drawings of some embodiments disclosed in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings. In addition, the drawings described below can be regarded as schematic diagrams, and are not limitations on the actual size of the products involved in the embodiments disclosed in the present invention, the actual process of the method, etc.

[0031] Figure 1 Shown is a schematic diagram of a usage scenario of the present invention.

[0032] Figure 2 Shown is an assembled isometric view of the present invention.

[0033] Figure 3 It is a partial cross-sectional assembly schematic diagram of the present invention.

[0034] Figure 4a Shown are the front view and cross-sectional view of the aluminum semicircular ring of the present invention.

[0035] Figure 4b Shown is an axonometric view of an aluminum half-ring of the present invention.

[0036] Figure 5a Shown is a front view of a steel semicircular ring of the present invention.

[0037] Figure 5b Shown is an axonometric view of a steel half-ring of the present invention.

[0038] Figure 5c Shown are the BB and CC cross-sectional views of the steel semicircular ring of the present invention.

[0039] Figure 5d Shown is a DD cross-sectional view of a steel semicircular ring of the present invention.

[0040] Figure 5e Shown are EE and FF cross-sectional views of the steel semicircular ring of the present invention.

[0041] Figure 6 Shown are the front view and cross-sectional view of the aluminum outer bushing of the present invention.

[0042] In the figure: 1 is an aluminum outer bushing, 2 is an axial positioning pin, 3 is a fastening nut, 4 is a steel semicircular ring, 5 is a tightening bolt, 6 is a radial positioning pin, 7 is a fastening bolt, 8 is a connecting screw, 9 is an aluminum semicircular ring, 10 is a machine tool tail top, 11 is a shell, 12 is a center frame auxiliary tooling for a thin-walled shell with a large aspect ratio, 13 is a center frame, 14 is a machine tool bed, and 15 is a machine tool chuck. DETAILED DESCRIPTION

[0043] The technical solutions in the embodiments of the present invention will be described clearly and completely below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0044] An auxiliary tooling for mounting a center frame on a thin-walled shell with a large aspect ratio, which comprises, from the inside to the outside, an aluminum semicircular ring 9, a steel semicircular ring 4, and an aluminum outer bushing 1;

[0045] There are two aluminum semicircular rings 9, which surround the outer circle of the shell 11 to form a first full circle;

[0046] There are two steel semicircular rings 4, which surround the outer circle of the first full circle to form a second full circle;

[0047] The aluminum outer bushing 1 surrounds the outer circle of the second full circle.

[0048] Two aluminum bosses are symmetrically arranged at one end of the outer circumferential surface of the aluminum semicircular ring 9, and the aluminum bosses are provided with radial threaded holes for connecting the steel semicircular ring 4; except for the aluminum bosses, the rest of the aluminum semicircular ring 9 is a thin-walled semicircular ring.

[0049] The upper and lower outer sides of both ends of the steel semicircular ring 4 are provided with steel boss structures, and the middle part of the steel boss is provided with a tightening threaded hole;

[0050] The tightening threaded hole includes a through hole, a pin hole, and a radial step through hole;

[0051] The through hole is used to connect the two steel semicircular rings;

[0052] The pin holes include axial positioning pin holes and radial positioning pin holes, which are used to position the two steel semicircular rings 4; in order to ensure the docking accuracy of the two steel semicircular rings 4 after disassembly and reassembly, the axial pin holes and the radial pin holes are processed after the two steel semicircular rings 4 are assembled into a full circle;

[0053] The radial step through hole is used to connect the two steel semicircular rings 4 and the two aluminum semicircular rings 9;

[0054] The steel semicircular ring 4 is a thick-walled semicircular ring; the steel semicircular ring 4 is provided with double rows of radially staggered and evenly distributed threaded holes for installing the tightening bolts 5 .

[0055] The aluminum outer bushing 1 is an aluminum thick-walled circular ring, which is a consumable part and has a radial thickness greater than 20 mm when in use.

[0056] The rotation axis of the first full circle coincides with the rotation axis of the housing 11; the rotation axis of the second full circle coincides with the rotation axis of the first full circle; the rotation axis of the aluminum outer bushing 1 coincides with the rotation axis of the second full circle;

[0057] The assembly sequence from inside to outside is: the shell 11 , the first full circle, the second full circle, and the aluminum outer bushing 1 .

[0058] The inner circle of the first full circle is in direct contact with the housing 11 with a clearance fit; the inner circle of the second full circle is in clearance fit with the outer circle of the first full circle; the inner circle of the aluminum outer bushing 1 is in transition fit with the outer circle of the second full circle.

[0059] The steel semicircular ring 4 is connected to the aluminum semicircular ring 9 by using screws 8 ; the two steel semicircular rings 4 are positioned by using radial positioning pins 6 and axial positioning pins 2 , and are fastened and connected by using fastening bolts 7 and fastening nuts 3 .

[0060] The steel semicircular ring 4 uses the tightening bolts 5 to tighten the aluminum semicircular ring 9 through the double-row radially staggered and evenly distributed threaded holes reserved on the thick-walled semicircular ring in the middle of the steel semicircular ring 4;

[0061] The aluminum semicircular ring 9 can partially deform to adapt to the irregular deformation of the outer circle of the shell 11 itself, and prevent the shell 11 from being damaged by the tightening bolt 5.

[0062] By adjusting the tightening bolts 5 installed on the steel semicircular ring 4, a preliminary correction is performed between the second full circle rotation axis and the rotation axis of the housing 11.

[0063] After each installation of the aluminum outer bushing 1, the outer circle of the aluminum outer bushing 1 needs to be completely turned to ensure that its rotation axis is coaxial with the rotation axis of the shell 11, so as to achieve precise correction of the rotation axis of the center frame auxiliary tooling 12 for the large aspect ratio thin-walled shell and the rotation axis of the thin-walled shell 11.

[0064] The invention is preferably used for auxiliary support in the process of turning the middle structure of a certain type of thin-walled shell with a large aspect ratio.

[0065] The present invention needs to be used on a lathe / CNC lathe equipped with a tailstock and a center frame. The specifications of the lathe / CNC lathe should meet the following requirements: the maximum rotation diameter through the pallet is greater than or equal to 450mm, the effective stroke of the Z axis is greater than or equal to 5000mm, the maximum clamping diameter of the center frame is greater than or equal to 560mm, and the minimum clamping diameter is less than or equal to 450mm.

[0066] The thin-walled shell with a large aspect ratio to be processed has been strengthened through heat treatment and has different degrees of deformation. It is a thin-walled cylindrical welded part with a turning structure in the middle. Except for the structure to be processed in the middle and the joints at both ends, the diameter of the shell is 370mm, the wall thickness is only 2.1mm, and the aspect ratio of the shell reaches 12:1.

[0067] The present invention is used to turn a certain type of thin-walled shell with a large aspect ratio, which can provide auxiliary support for the middle part of the shell during the turning process, solve the vibration problem during the turning process of the middle structure of the shell, and ensure the scientific research and production tasks of the shell.

[0068] The use scenarios of the large aspect ratio thin-walled shell center frame auxiliary tooling of the present invention are as follows: Figure 1 As shown, one end of the shell 11 is clamped by a machine tool chuck 15, and the other end is tightened by a machine tool tail 10. The large aspect ratio thin-walled shell center frame auxiliary tooling 12 is installed in the shell 11 near the middle of the shell to be processed structure 11-1. The center frame 13 is installed on the machine tool bed 14 and adjusted to a suitable position. It is mounted on the large aspect ratio thin-walled shell center frame auxiliary tooling 12 in a three-point support manner for auxiliary support.

[0069] Preferably, the through holes at both ends of the two steel semicircular rings 4 are aligned, and the two steel semicircular rings 4 are fastened and connected to form a second full circle using fastening bolts 7 and fastening nuts 3. Figure 5a The radial positioning pin holes and the axial positioning pin holes are provided at the positions shown to ensure the consistency of the two steel semicircular rings 4 after disassembly and reassembly.

[0070] Preferably, Figure 2 , Figure 3 As shown, the radial threaded hole at one end of the aluminum semicircular ring 9 is aligned with the radial step through hole at either end of the steel semicircular ring 4, and connected using connecting screws 8. The two aluminum semicircular rings 9 surround the housing 11 to form a first full circle, and the two steel semicircular rings 4 surround the outer circle of the first full circle to form a second full circle.

[0071] Preferably, Figure 2 , Figure 3 As shown, the radial positioning pin 6 is installed in the radial positioning pin hole formed by the two steel semicircular rings 4, and the axial positioning pin 2 is installed in the axial positioning pin hole formed by the two steel semicircular rings 4.

[0072] Preferably, Figure 2 , Figure 3 As shown, the jacking bolt 5 is installed in the double-row radially staggered threaded holes in the middle of the steel semicircular ring 4, and the head of the jacking bolt 5 contacts the outer circle of the aluminum semicircular ring 9. By adjusting the jacking bolt 5, the following can be achieved:

[0073] 1 The thin-walled part of the aluminum semicircular ring 9 is deformed along with the shell 11, and the large aspect ratio thin-walled shell with center frame auxiliary tooling 12 is more closely fitted to the shell 11;

[0074] 2. Preliminarily calibrate the outer circle of the second full circle to maximize the coaxiality between the rotation axis of the steel semicircular ring 4 and the rotation axis of the housing 11;

[0075] The steel semicircular ring 4 and the aluminum semicircular ring 9 are firmly mounted on the housing 11.

[0076] Preferably, Figure 2 , Figure 3 As shown, the aluminum outer bushing 1 is installed on the steel semicircular ring 4, and the inner circle of the aluminum outer bushing 1 is clearance-matched with the outer circle of the second full circle. After the aluminum outer bushing 1 is installed, the outer circle of the aluminum outer bushing 1 is turned until it is smooth. When turning the outer circle of the aluminum outer bushing 1, the large aspect ratio thin-walled shell center frame auxiliary tooling 12 rotates with the shell 11 to ensure that the rotation axis of the aluminum outer bushing 1 is coaxial with the rotation axis of the shell 11, and the precise calibration of the large aspect ratio thin-walled shell center frame auxiliary tooling 12 is completed.

[0077] After completing the precise calibration of the center frame auxiliary tooling 12 of the large aspect ratio thin-walled shell, the center frame 13 can be installed on the outer circle of the aluminum outer bushing 1 using a three-point support method to achieve auxiliary support for the middle part of the shell 11.

[0078] Although the present invention has been disclosed as above in the form of a preferred embodiment, it is not intended to limit the present invention. Any person skilled in the art may make possible changes and modifications to the technical solution of the present invention using the above disclosed contents without departing from the spirit and scope of the present invention. Therefore, any simple modifications, equivalent changes and modifications made to the above embodiments based on the technical essence of the present invention without departing from the contents of the technical solution of the present invention shall fall within the protection scope of the technical solution of the present invention.

Claims

1. An auxiliary tooling for assembling a center frame for a thin-walled shell with a large aspect ratio, characterized in that: It includes, from the inside to the outside, an aluminum semicircular ring (9), a steel semicircular ring (4), and an aluminum outer bushing (1); The aluminum semicircular rings (9) are two in number and surround the outer circle of the shell (11) to form a first full circle; The steel semicircular rings (4) are in two numbers, surrounding the outer circle of the first full circle to form a second full circle; The aluminum outer bushing (1) surrounds the outer circle of the second full circle.

2. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: Two aluminum bosses are symmetrically arranged at one end of the outer circumferential surface of the aluminum semicircular ring (9), and the aluminum bosses are provided with radial threaded holes for connecting with the steel semicircular ring (4).

3. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: The upper and lower outer sides of both ends of the steel semicircular ring (4) are provided with steel boss structures, and the middle of the steel boss is provided with a tightening threaded hole; The tightening threaded hole includes a through hole, a pin hole, and a radial step through hole; The through hole is used to connect the two steel semicircular rings; The pin holes include an axial positioning pin hole and a radial positioning pin hole, which are used to position the two steel semicircular rings (4); The radial step through hole is used to connect the two steel semicircular rings (4) and the two aluminum semicircular rings (9); The steel semicircular ring (4) is a thick-walled semicircular ring; the steel semicircular ring (4) is provided with double rows of radially staggered and evenly distributed threaded holes for installing tightening bolts (5).

4. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: The aluminum outer bushing (1) is an aluminum thick-walled ring.

5. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: The rotation axis of the first full circle coincides with the rotation axis of the housing (11); The rotation axis of the second full circle coincides with the rotation axis of the first full circle; The rotation axis of the aluminum outer bushing (1) coincides with the rotation axis of the second full circle.

6. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: The inner circle of the first full circle is in direct contact with the shell (11) by clearance fit; the inner circle of the second full circle is in clearance fit with the outer circle of the first full circle; and the inner circle of the aluminum outer bushing (1) is in transition fit with the outer circle of the second full circle.

7. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: The steel semicircular ring (4) and the aluminum semicircular ring (9) are connected by screws (8); the two steel semicircular rings (4) are positioned by radial positioning pins (6) and axial positioning pins (2), and are fastened and connected by fastening bolts (7) and fastening nuts (3).

8. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: The steel semicircular ring (4) uses the tightening bolt (5) to tighten the aluminum semicircular ring (9) through the double-row radially staggered and evenly distributed threaded holes reserved on the thick-walled semicircular ring in the middle of the steel semicircular ring (4).

9. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: By adjusting the tightening bolt (5) installed on the steel semicircular ring (4), a preliminary correction is performed between the second full circle rotation axis and the rotation axis of the housing (11).

10. The auxiliary tooling for erecting a center frame for a thin-walled shell with a large aspect ratio according to claim 1, characterized in that: After each installation of the aluminum outer bushing (1), the outer circumference of the aluminum outer bushing (1) needs to be completely turned to ensure that its rotation axis is coaxial with the rotation axis of the shell (11), so as to achieve accurate correction of the rotation axis of the auxiliary tooling (12) for the large aspect ratio thin-walled shell center frame and the rotation axis of the thin-walled shell (11).

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