阅读说明：本技术 一种通用钣焊钛合金舱体加工方法 (Method for processing general titanium alloy cabin welded by metal plate ) 是由 吴高生 蹇悦 俞玉明 郑方志 姜俊声 殷伟 张永升 于 2020-11-30 设计创作，主要内容包括：本发明公开了一种战术导弹钛合金钣焊结构舱体的通用加工方法,主要包括前端框粗加工,后端框粗加工,焊接蒙皮卷和前后端框,半精车舱体端面和内外圆,制舱体焊接工艺孔,焊接舱体内部零件,半精车舱体外圆,精车舱体内外圆,精加工舱体端面所有特征、精加工舱体周向所有特征,对舱体去毛刺,超声波清洗和总检、包装、入库等十余个步骤。在本发明中,采用先加工前后端框,再蒙皮焊接整体加工的方法保证产品最终精度。采用专用柔性夹具,实现对薄壁舱体零件的柔性装夹,有效控制装夹变形,解决零件车削过程中的振动问题。(The invention discloses a general processing method of a tactical missile titanium alloy plate welding structure cabin body, which mainly comprises more than ten steps of rough processing of a front end frame, rough processing of a rear end frame, welding of a skin roll, the front end frame and the rear end frame, semi-finish machining of the end surface and the inner and outer circles of a cabin body, cabin body welding process holes, welding of internal parts of the cabin body, semi-finish machining of the outer circle of the cabin body, finish machining of all characteristics of the end surface of the cabin body, finish machining of all characteristics of the circumference of the cabin body, deburring of the cabin body, ultrasonic cleaning, general inspection, packaging, warehousing and the like. In the invention, the final precision of the product is ensured by adopting a method of firstly processing the front end frame and the rear end frame and then welding the skin for integral processing. By adopting the special flexible fixture, the flexible clamping of the thin-wall cabin part is realized, the clamping deformation is effectively controlled, and the vibration problem in the turning process of the part is solved.)

1. A general processing method for a titanium alloy cabin welded by a metal plate is characterized by comprising the following steps:

step 1, roughly machining a front end frame and a rear end frame, and welding a skin roll and the front end frame and the rear end frame;

step 2, roughly turning the outer circle of the cabin body; roughly machining an inner cavity and an end face positioning hole of the cabin body; two end faces and an inner circle of the rough cabin body;

step 3, positioning and clamping by using end face holes, drilling welding process holes of circumferential parts by using a vertical boring tool, and performing resistance spot welding on the internal gasket, the boss and the cabin body through the welding process holes;

step 4, clamping by using a choke plug, and finely turning the outer circle of the cabin body; finish machining the inner cavity and the end face positioning hole of the cabin body by using a horizontal boring tool; supporting an excircle by using a flexible center frame, and finely turning two end faces and an inner circle of the cabin body;

step 5, positioning and clamping by using end surface holes, and processing the circumferential characteristics of the cabin by using a vertical boring tool;

and 6, deburring by a bench worker, cleaning, inspecting, oil sealing and warehousing.

2. The general processing method for the titanium alloy cabin welded by the plate according to claim 1, wherein the step 1 specifically comprises the following steps:

step 1.1, the front end frame and the rear end frame adopt the technological processes of rough turning of an outer circle and an inner hole, rough milling of an inner contour and semi-finish turning of the outer circle and the inner hole; wherein, when the front end frame and the rear end frame are roughly processed, 1.5mm of finish turning allowance is left on one side of the outer circle, and 2mm of finish milling allowance is left on one side of the inner contour;

step 1.2, roughly processing the front end frame and the rear end frame, wherein an inner hole of the end frame is matched and turned with an inner hole of the skin coil within a range of 15mm from a welding end face, an inner hole of the end frame is matched and turned with an outer circle of the skin coil, numbers are made on the front end frame and the rear end frame and are consistent with the numbers of the skin coil, and evenly dividing and scribing are carried out at the position of 45 degrees of the outer circle of the front end frame to specify the longitudinal seam welding position;

and step 1.3, when the skin is welded with the front end frame and the rear end frame, pairing the front end frame, the rear end frame and the skin roll according to the principle that the serial numbers are the same, taking an arrow as the direction of the front end frame, aligning the position of the longitudinal seam of the skin roll with the front end frame by 45-degree equal division lines, and strictly controlling the deformation of the welding cabin body in the welding process.

3. The general processing method for the titanium alloy cabin welded by the plate according to claim 1, wherein the step 2 specifically comprises the following steps:

step 2.1, clamping by using inner outlines at two ends of the cabin body through choke plugs, correcting an excircle according to the dimensional accuracy of a product drawing, and semi-finish turning the excircle diameter of two end frames to be the outer diameter D +2mm of the cabin body product drawing;

2.2, clamping the cabin body by using soft claws to clamp the outer circle of the cabin body and then supporting the cabin body by using a central frame, roughly turning two end faces of the cabin body and the inner circle of the cabin body, and ensuring that the total length of the cabin body is L +2mm and the inner diameter dimension is d-2mm of the inner diameter of a cabin body product diagram;

step 2.3, manufacturing a circumferential positioning hole of the cabin body, wherein the hole position is selected at a position needing to be processed in the circumferential follow-up of the cabin body;

and 2.4, positioning and clamping by using the positioning holes manufactured in the step 2.3, clamping the cabin body by horizontal boring, drilling the end face process holes, and selecting the subsequent processing positions of the end face of the cabin body according to the positions of the holes.

4. The general processing method for the titanium alloy cabin welded by the plate according to claim 1, wherein the step 3 specifically comprises the following steps:

step 3.1, drilling end face positioning holes by using the step 2.4, erecting a boring tool, clamping a cabin body, and processing welding process holes of all circumferential parts;

3.2, mounting small bosses which are difficult to process on the inner wall of the cabin body by using the welding process holes, nuts and screws manufactured in the step 3.1, and connecting each boss with the cabin body in a resistance spot welding mode;

3.3, positioning by utilizing the bottom and the excircle of the front end frame and the end face positioning hole manufactured in the step 2.4, erecting a boring tool and clamping the cabin body, and machining a large component mounting hole;

and 3.4, connecting and installing the large component to the inner wall of the cabin body by using the large component installation hole manufactured in the step 3.3.

5. The general processing method for the titanium alloy cabin welded by the plate according to claim 1, wherein the step 4 specifically comprises the following steps:

step 4.1, clamping the inner contour of the cabin body by using choke plugs at two ends, correcting the excircle according to the product drawing size precision according to the product drawing, and semi-finish turning the excircle of two end frames to the outer diameter D +1mm of the size cabin body product drawing;

step 4.2, clamping the cabin body by using the soft claws to clamp the outer circle of the cabin body and then supporting the cabin body by using a center frame, correcting the outer circle and the circle center according to the size precision of a cabin body product drawing, finely turning two end faces of the cabin body to the size of the product drawing, and finely turning the butt joint of the interior of the cabin body to the size of the product drawing;

step 4.3, clamping by using a mode of plugging heads on two ends of the cabin body, correcting the excircle according to the size precision of a cabin body product drawing, finely turning the excircle to the size of the product drawing, and finely turning the butt joint of the excircle of the cabin body to the size of the product drawing;

and 4.4, prefabricating the circumferential positioning holes in the step 2.3, clamping the cabin body by a horizontal boring tool, and processing the end surface characteristics to the size of a product drawing.

6. The general processing method for the titanium alloy cabin welded by the plate according to claim 1, wherein in the cabin turning procedure, the processing clamp adopts flexible claws to clamp the excircle at one end of the cabin, and then the excircle at the other end of the cabin is supported by a center frame; the center frame adopts a special flexible center frame, flexible clamping of the thin-wall cabin body part is realized, clamping deformation is effectively controlled, and the problem of vibration in the turning process of the part is solved.

7. The general processing method for the titanium alloy cabin welded by the plate according to claim 1, wherein after the cabin is cut, all remainders such as burrs, process screws and the like on the cabin are removed; immersing the cabin body into an ultrasonic cleaning tank for cleaning, wherein the cleaning solution is purified water and alkaline cleaning agent; cleaning the inner wall and the outer wall of the cabin body in a high-temperature and high-pressure water spraying mode to clean residual stains possibly left on the cabin body; and drying the cabin body at high temperature.

8. The general processing method for the plate-welded titanium alloy cabin according to claim 6, wherein the flexible center frame is suitable for long-cylinder easily-deformable thin-walled parts and comprises the following steps: the device comprises a base, a baffle, a front bearing assembly, a rotating shaft, a rolling bearing and a rear bearing assembly; the front support assembly is arranged on the rotating shaft and used for supporting the thin-walled part; the rear supporting component is arranged on the baffle and is used for supporting and limiting the thin-walled part; the base and the rotating shaft are respectively in interference fit with the rolling bearing, the outer ring of the bearing is fixed on the base, and the inner ring and the rotating shaft rotate; the baffle is arranged on the rotating shaft and used for supporting and fixing the bearing inner ring.

9. The general processing method for the plate-welded titanium alloy cabin according to claim 8, is characterized by comprising the following steps: the front bearing assembly comprises an adjusting screw, a tightening nut, a front bearing frame and a bearing leg; the tightening nut is in threaded connection with the adjusting screw and is used for fixing the adjusting screw; the adjusting screw is in threaded fit with the front support frame, the adjusting screw is connected with the support leg through a groove through a tail ball end, the support leg can slide in the front support frame, and the front support frame is screwed on the rotating shaft; the rear support assembly comprises a screw, a tightening nut and a rear support; the screwing nut is in threaded connection with the screw, the screw is in threaded connection with the rear support frame, and the rear support frame is in threaded connection with the baffle; the rolling bearing is in interference fit with the base and the rotating shaft respectively, the outer ring is fixed on the base, and the inner ring rotates along with the rotating shaft; the baffle is screwed on the rotating shaft; the front supporting component supports the thin-walled part, and the rear supporting component supports and limits the thin-walled part, wherein: the arc surface of the supporting foot for supporting changes along with the diameter change of the thin-wall part; the rotating shaft, the baffle plate, the front and rear supporting assemblies and the rolling bearing rotate along with the rotation of the thin-wall part as a whole.

Technical Field

The invention belongs to the field of welding thin-wall part machining, relates to a method for machining a tactical missile cabin, and particularly relates to a general method for machining a titanium alloy cabin welded on a metal plate of a tactical missile.

Background

The capsule body is used as an important component in the missile structure and is an installation carrier of each part and precision equipment. In order to meet the test of large flight intensity and complex environment in the test process, the cabin body is complex in structural design and high in machining precision. Meanwhile, in consideration of missile lightweight, the cabin body is mostly of a thin-wall weak rigid structure, and the manufacturing difficulty is high. With the diversification and the complication of the use requirements of tactical weapons, many structural characteristics of the casting type cabin body cannot be realized by casting due to the limitation of casting and processing, and the sheet metal welding type cabin body is wide in processing mode, relates to multiple specialties (including welding, machining, sheet metal, riveting and the like), meets the design requirements of complex structures, and is gradually applied to tactical missiles of high-strength flight tests.

At present, the plate welding type cabin bodies are more in plate welding titanium alloy cabin bodies, are applied to various types of plate welding titanium alloy cabin bodies, are different in specification and processing method, are different in technological equipment required by a technological method, improve the production cost, and simultaneously improve higher requirements on production scheduling due to different technological routes caused by different technological methods.

Disclosure of Invention

Aiming at the defects of high input cost of process equipment and high production and scheduling difficulty caused by the only special process method of the existing plate welding type titanium alloy cabin body, the invention aims to provide a universal plate welding type titanium alloy cabin body processing method and provide guidance for processing multi-type and multi-specification plate welding type titanium alloy cabin bodies.

The invention relates to a general processing method for a titanium alloy cabin welded by a metal plate, which is characterized by comprising the following steps:

step 1, roughly machining a front end frame and a rear end frame, and welding a skin roll and the front end frame and the rear end frame;

step 2, roughly turning the outer circle of the cabin body by using choke plug clamping; roughly machining the inner cavity and the end face positioning holes of the cabin body by using a horizontal boring tool; supporting an outer circle by using a flexible center frame, roughly turning two end faces and an inner circle of the cabin body;

step 3, positioning and clamping by using end face holes, drilling welding process holes of circumferential parts by using a vertical boring tool, and performing resistance spot welding on the internal gasket, the boss and the cabin body through the welding process holes;

step 4, clamping by using a choke plug, and finely turning the outer circle of the cabin body; finish machining the inner cavity and the end face positioning hole of the cabin body by using a horizontal boring tool; supporting an excircle by using a flexible center frame, and finely turning two end faces and an inner circle of the cabin body;

step 5, positioning and clamping by using end surface holes, and processing the circumferential characteristics of the cabin by using a vertical boring tool;

and 6, deburring by a bench worker, cleaning, inspecting, oil sealing and warehousing.

Further, the step 1 specifically includes:

step 1.1, the front end frame and the rear end frame adopt the technological processes of rough turning of an outer circle and an inner hole, rough milling of an inner contour and semi-finish turning of the outer circle and the inner hole. Wherein, when the front end frame and the rear end frame are roughly processed, 1.5mm of finish turning allowance is left on one side of the outer circle, and 2mm of finish milling allowance is left on one side of the inner contour;

step 1.2, the inner hole of the end frame needs to be matched with the inner hole of the skin coil and the inner hole of the end frame needs to be matched with the outer circle of the skin coil within a range 15mm from the welding end surface during the rough machining of the front end frame and the rear end frame, and the serial numbers are made on the front end frame and the rear end frame and are consistent with the serial numbers of the skin coil. Equally dividing the 45-degree position of the excircle of the front end frame to define the longitudinal seam welding position;

and step 1.3, when the skin is welded with the front end frame and the rear end frame, pairing the front end frame, the rear end frame and the skin roll according to the principle that the serial numbers are the same, taking an arrow as the direction of the front end frame, aligning the position of the longitudinal seam of the skin roll with the front end frame by 45-degree equal division lines, and strictly controlling the deformation of the welding cabin body in the welding process.

Further, the step 2 specifically includes:

step 2.1, clamping by using inner outlines at two ends of the cabin body through choke plugs, correcting an excircle according to the dimensional accuracy of a product drawing, and semi-finish turning the excircle of two end frames to reach the dimension (the outer diameter D +2) mm;

2.2, clamping the cabin body by using soft claws to clamp the outer circle of the cabin body and then supporting the cabin body by using a central frame, roughly turning two end faces of the cabin body and the inner circle of the cabin body to ensure that the total length of the cabin body is (the total length L +2) mm and the inner diameter dimension is (the inner diameter d-2) mm of a cabin body product diagram;

step 2.3, manufacturing a circumferential positioning hole of the cabin body, wherein the hole position is selected at a position needing to be processed in the circumferential follow-up of the cabin body;

2.4, positioning and clamping by using the positioning holes manufactured in the step 2.3, clamping the cabin body by horizontal boring work, drilling an end face process hole, and selecting a subsequent processing position of the end face of the cabin body at the position of the hole;

further, the step 3 specifically includes:

step 3.1, drilling end face positioning holes by using the step 2.4, erecting a boring tool, clamping a cabin body, and processing welding process holes of all circumferential parts;

3.2, mounting small bosses which are difficult to process on the inner wall of the cabin body by using the welding process holes, nuts and screws manufactured in the step 3.1, and connecting each boss with the cabin body in a resistance spot welding mode;

3.3, positioning by utilizing the bottom and the excircle of the front end frame and the end face positioning hole manufactured in the step 2.4, erecting a boring tool and clamping the cabin body, and machining a large component mounting hole;

and 3.4, connecting and installing the large component to the inner wall of the cabin body by using the large component installation hole manufactured in the step 2.7.

Further, the step 4 specifically includes:

step 4.1, clamping the inner contour of the cabin body by using choke plugs at two ends, correcting the excircle according to the product drawing according to the size precision of the product drawing, and semi-finish turning the excircle of two end frames to the size (D +1) mm;

step 4.2, clamping the cabin body by using the soft claws to clamp the outer circle of the cabin body and then supporting the cabin body by using a center frame, correcting the outer circle and the circle center according to the size precision of a cabin body product drawing, finely turning two end faces of the cabin body to the size of the product drawing, and finely turning the butt joint of the interior of the cabin body to the size of the product drawing;

step 4.3, clamping by using a mode of plugging heads on two ends of the cabin body, correcting the excircle according to the size precision of a cabin body product drawing, finely turning the excircle to the size of the product drawing, and finely turning the butt joint of the excircle of the cabin body to the size of the product drawing;

step 4.4, prefabricating the circumferential positioning holes in the step 2.3, clamping the cabin body by a horizontal boring tool, and processing the end surface characteristics to the size of a product drawing;

further, in the cabin turning procedure, the soft claws are adopted for clamping the excircle at one end of the cabin in the machining and clamping process, and then the center frame is used for supporting the excircle at the other end of the cabin. The center frame adopts a special flexible center frame, flexible clamping of the thin-wall cabin body part is realized, clamping deformation is effectively controlled, and the problem of vibration in the turning process of the part is solved.

Further, after the cabin body is cut, all the remainders such as burrs, process screws and the like on the cabin body need to be removed; immersing the cabin body into an ultrasonic cleaning tank for cleaning, wherein the cleaning solution is purified water and alkaline cleaning agent; cleaning the inner wall and the outer wall of the cabin body in a high-temperature and high-pressure water spraying mode to clean residual stains possibly left on the cabin body; and drying the cabin body at high temperature.

Further, the special flexible center frame suitable for the long-cylinder easily-deformable thin-walled part comprises: the bearing comprises a base, a baffle, a front bearing assembly, a rotating shaft, a rolling bearing and a rear bearing assembly. The front support assembly is arranged on the rotating shaft and used for supporting the thin-walled part; the rear supporting component is arranged on the baffle and is used for supporting and limiting the thin-walled part; the base and the rotating shaft are respectively in interference fit with the rolling bearing, the outer ring of the bearing is fixed on the base, and the inner ring and the rotating shaft rotate; the baffle is arranged on the rotating shaft and used for supporting and fixing the bearing inner ring.

Further, the special flexible center frame suitable for the long-cylinder easily-deformable thin-walled part specifically comprises:

said front support assembly includes: adjusting screws, tightening nuts, a front support frame and support legs. The tightening nut is in threaded connection with the adjusting screw and is used for fixing the adjusting screw; the adjusting screw is in threaded fit with the front support frame, the adjusting screw is connected with the support leg through a groove through a tail ball end, the support leg can slide in the front support frame, and the front support frame is screwed on the rotating shaft;

② said rear support assembly includes: screws, tightening nuts, and a rear support. The screwing nut is in threaded connection with the screw, the screw is in threaded connection with the rear support frame, and the rear support frame is in threaded connection with the baffle;

thirdly, the base is fixed and is in interference fit with the rolling bearing;

the rolling bearing is in interference fit with the base and the rotating shaft respectively, the outer ring is fixed on the base, and the inner ring rotates along with the rotating shaft;

the rotating shaft is in interference fit with the rolling bearing;

sixthly, the baffle is screwed on the rotating shaft;

the front supporting component supports the thin-wall part, the rear supporting component supports and limits the thin-wall part, wherein: the arc surface of the supporting foot for supporting changes along with the diameter change of the thin-wall part;

the rotating shaft, the baffle, the front and rear support assemblies and the rolling bearing rotate along with the rotation of the thin-wall part as a whole.

The invention has the following advantages:

(1) the method serves as a general processing technique and can guide the processing of the cabin body with the weak rigid structure of the titanium alloy plate welding structure of a plurality of types and specifications;

(2) the investment cost of process equipment and tools can be reduced;

(3) the device can be expanded and applied to more equipment for processing;

(4) the processing efficiency and the quality stability of the parts can be improved.

Drawings

Other advantages and benefits of the present invention will become apparent from the detailed description of the invention which follows.

FIGS. 1-8 are process diagrams required by the processing technology of a titanium alloy cabin body welded by a plate, and FIGS. 9-10 are related views of a special flexible center frame suitable for a long-cylinder deformable thin-wall part; wherein 1 is a front bearing assembly, 2 is a rotating shaft, 3 is a base, 4 is a rear bearing assembly, 5 is a baffle, and 6 is a rolling bearing.

Detailed Description

In order to embody the advancement of the present invention, embodiments of the present invention will be described in detail with reference to the accompanying drawings and examples. It is worth noting that several minor modifications made on the design framework of the present invention are within the scope of protection of the present invention.

Examples of the embodiments

Taking a certain type of plate welding type titanium alloy guiding flight control cabin as an example, the outer diameter of a part is 300mm, the total length is 698.4mm, a central frame required in the process method is a special flexible central frame suitable for a long-tube easily-deformable thin-wall part, and as shown in attached figures 9-10, the overhanging length of a front supporting foot and a rear supporting foot can be adjusted according to the outer diameter of a clamped part to powerfully support a cabin body. The front support assembly 1 and the rotating shaft 2 of the reformed center frame are in threaded connection, the rear support assembly 4 and the baffle plate 5 are in threaded connection, the rolling bearing 6 is in interference fit with the base 3 and the rotating shaft 2 respectively, the outer ring is fixed, and the inner ring rotates. The cabin rotates to drive the rolling bearing in the reformed center frame to rotate together. Compared with the rolling contact of the roller of the traditional center frame and the cabin body, the remanufactured center frame is suitable for the turning processing of the cabin body with any excircle roundness, the problem of contact clearance between the cabin body and the auxiliary support caused by insufficient excircle roundness is solved, the vibration of the tool in the turning process is avoided, the abrasion of the tool is reduced, and the manufacturing precision and the surface quality of the cabin body are improved.

The present invention will be further described below by way of this example.

Step 1, roughly machining a front end frame part according to a graph 1, roughly turning an outer circle to(300+3), reserving 1.5mm of post-welding machining allowance on one side, and reserving 2mm of post-welding machining allowance on one side of the rough-milled inner contour. Vehicle with welded end and covering on end frameOuter circle andan inner hole is formed, and the turning length is ensured to be 15 mm.

Step 2, according to the figure 2, roughly machining the rear end frame part, roughly turning the excircle to(300+3), reserving 1.5mm of postweld machining allowance on one side, and roughly turning an inner hole to(287+2)And reserving 1mm of post-welding machining allowance at the single side. Vehicle with welded end and covering on end frameOuter circle andan inner hole is formed, and the turning length is ensured to be 15 mm.

And 3, welding the front end frame, the rear end frame and the skin roll according to the attached drawing 3, and paying attention to the welding process: the excircle size of the front end frame and the back end frame only leaves 1.5mm of allowance for machining after welding, the allowance is small, and the deformation of the welding cabin body is strictly controlled; the front end frame, the rear end frame and the skin roll are matched in pairs on the principle of same serial number, and an arrow is in the direction of the front end frame; the longitudinal seam position of the skin roll is aligned with the 45-degree equal division lines of the front end frame.

Step 4, clamping two inner contours by using a choke plug, correcting the appearance, turning the outer circle to the position that the jumping amount is not more than 0.1(300+2)；

Step 5, clamping the excircle by using a soft jaw chuck at the left end, using a center frame for auxiliary support at the right end according to the attached figure 4, adjusting the overhanging length of a front supporting leg and a rear supporting leg according to the excircle size, correcting the excircle runout to be not more than 0.05, turning the right end face to be not more than 0.1, and ensuring the roughness to be 3.2 and the verticality to be 0.1, wherein the right end face is turned to 701.4 +/-0.1 (698.4+ 3); turning an inner hole at the right end to phi 287 +/-0.1 (289-2), and ensuring that the roughness is 3.2 and the coaxiality is 0.1; turning around and clamping according to the attached drawing 3, clamping the excircle by using a soft jaw chuck at the left end, supporting the right end by using a center frame in an auxiliary way, correcting the excircle runout to be not more than 0.05, and turning the right end face to a size of 700.4 +/-0.1 (698.4+2), wherein the roughness is 3.2, and the verticality is 0.1;

step 6, drilling a circumferential positioning hole of the cabin body according to the attached figure 6

Step 7, prefabricating the fabrication holes in the step 5Positioning, horizontally boring, clamping the parts, and drilling an end face process hole according to the attached figure 5

Step 8, according to the attached figure 8, referring to a product drawing and an attached figure 7, processing the welding process hole with the boss difficult to process insideA through hole;

step 9, performing acid cleaning on the cabin body and all the lugs to be welded for pretreatment before welding, referring to a process diagram 7, positioning and installing the lug boss in the cabin body by using screws, nuts and the prefabricated process holes in the step 7, and connecting the cabin body and the lug boss by using a resistance spot welding mode;

step 10, erecting a boring tool to clamp the cabin body, and prefabricating the bottom and the outer circle of the front end frame and the step 6And positioning, drilling a large part process hole, and mounting the large part inside the cabin body by using a countersunk rivet.

Step 11, clamping the profile by using a choke plug, finely adjusting and correcting the appearance of the part at two ends, turning the outer circle to the size, wherein the jumping amount is not more than 0.05(300+1)；

Step 12, clamping the outer circle of the front end frame by using a soft jaw chuck at the left end, using a center frame for auxiliary support at the right end, adjusting the overhanging length of a front supporting leg and a rear supporting leg according to the size of the outer circle, correcting the jumping quantity of the outer circle to be not more than 0.05, turning the end surface of the rear end frame to ensure the size of 699.4 +/-0.1 and considering the size of 43.4(40+ 3.4); turning the inner circle toEnsure the dimensions of 40.6(37.2+3.4), 38.7(35.3+3.4) and the coaxialityThe vehicle interior butt joint is up to the product drawing size;

step 13, clamping the outer circle of the rear end frame at the left end by using a soft jaw chuck, using a center frame for auxiliary support at the right end, adjusting the overhanging length of a front supporting leg and a rear supporting leg according to the size of the outer circle, correcting the jumping quantity of the outer circle to be not more than 0.05, correcting the jumping quantity of the right end face to be not more than 0.05, and turning the total length to the size of a product drawing;

step 14, clamping the inner contour by using two choke plugs, correcting the appearance, turning the outer circle to the size of a product drawing, and turning the step surface of the outer circle and the sealing groove to the size of the product drawing, wherein the jumping amount is not more than 0.05;

step 15, horizontally boring, assembling and clamping parts, positioning by using the prefabricated circumferential process holes in the step 5, and processing all end surface characteristics of the cabin body;

step 16, end milling tooling clamping parts, using the bottom part and the excircle of the front end frame andpositioning and processing all vertical characteristics of cabin body'

And step 17, removing all burrs on the cabin body, immersing the cabin body into an ultrasonic cleaning tank for cleaning, wherein the cleaning solution is purified water and an alkaline cleaning agent, cleaning the inner wall and the outer wall of the cabin body by using a high-temperature high-pressure water spraying mode, cleaning residual stains possibly remained on the cabin body, and finally drying the cabin body at high temperature.

And step 15, inspecting, packaging and warehousing.

As shown in fig. 9 and 10, a special flexible center frame suitable for a long-tube easily-deformable thin-wall part comprises: the device comprises a base 3, a baffle 5, a front bearing assembly 1, a rotating shaft 2, a rolling bearing 6 and a rear bearing assembly 4. The front support assembly is arranged on the rotating shaft and used for supporting the thin-walled part; the rear supporting component is arranged on the baffle and is used for supporting and limiting the thin-walled part; the base and the rotating shaft are respectively in interference fit with the rolling bearing, the outer ring of the bearing is fixed on the base, and the inner ring and the rotating shaft rotate; the baffle is arranged on the rotating shaft and used for supporting and fixing the bearing inner ring.

Further, the special flexible center frame suitable for the long-cylinder easily-deformable thin-walled part specifically comprises:

said front support assembly includes: as shown in fig. 10, adjusting screws, tightening nuts, front support brackets, and support legs. The tightening nut is in threaded connection with the adjusting screw and is used for fixing the adjusting screw; the adjusting screw is in threaded fit with the front support frame, the adjusting screw is connected with the support leg through the groove through the tail T-shaped groove, the support leg can slide in the front support frame, and the front support frame is screwed on the rotating shaft. After the titanium alloy cabin body with the metal plate welding structure is welded by the front end frame and the rear end frame, the roundness of the front end frame and the rear end frame is lower due to welding thermal deformation, and the excircle is deformed into an ellipse. In the turning process, the position with the maximum excircle deformation is supported by the front support frame, so that the cabin body is in seamless contact with the flexible center frame, the turning vibration caused by the contact gap between the cabin body with low roundness and the traditional center frame is avoided, the quality of the processed surface is improved, and the turning device is suitable for turning any roundness thin-wall cabin body. And moreover, the corresponding front support frame can be adapted according to the outer diameter of the machined cabin body, and the method is suitable for cabin body turning of various specifications.

② said rear support assembly includes:

screws, tightening nuts, and a rear support. The tightening screw cap is in threaded connection with the screw, the screw is in threaded connection with the rear support frame, and the rear support frame is in threaded connection with the baffle and used for auxiliary support of the cabin body;

thirdly, the base is fixed and is in interference fit with the rolling bearing;

the rolling bearing is in interference fit with the base and the rotating shaft respectively, the outer ring is fixed on the base, and the inner ring rotates along with the rotating shaft;

the rotating shaft is in interference fit with the rolling bearing;

sixthly, the baffle is screwed on the rotating shaft;

the front supporting component supports the thin-wall part, the rear supporting component supports and limits the thin-wall part, wherein: the arc surface of the supporting foot for supporting changes along with the diameter change of the thin-wall part;

the rotating shaft, the baffle, the front and rear support assemblies and the rolling bearing rotate along with the rotation of the thin-wall part as a whole.

The invention has the following advantages: (1) the method serves as a general processing technique and can guide the processing of the cabin body with the weak rigid structure of the titanium alloy plate welding structure of a plurality of types and specifications; (2) the investment cost of process equipment and tools can be reduced; (3) the device can be expanded and applied to more equipment for processing; (4) the processing efficiency and the quality stability of the parts can be improved.