Precision machining tool and method for two split type thin-wall cylindrical complex components

Abstract

The invention relates to a two-split type thin-wall cylindrical complex component precision machining tool and method, and the method comprises the steps: 1, rough machining: machining outer arc parts of two split parts, B end surfaces perpendicular to the axial directions of the two split parts, bottom surfaces parallel to the B end surfaces, buckling contact C surfaces of the two split parts, inner cavity gaps and inner cavity circular surfaces, a first auxiliary device is adopted for clamping and fixing the component during machining of all the circular faces of the inner cavity; 2, performing stress relief annealing to perform heat treatment on the component; 3, semi-finish machining is carried out, specifically, the end faces B, perpendicular to the axial direction, of the two split parts and the bottom faces parallel to the end faces B are machined, the two split parts are buckled to make contact with the face C and all the round faces of an inner cavity, and a first auxiliary device is adopted for clamping and fixing the component in the machining process of all the round faces of the inner cavity; 4, heat treatment is conducted on the component in a stress relief annealing and high-low temperature stable treatment mode; and 5, finish machining is conducted, specifically, the C faces of the two split parts are ground and machined, and the components are fixed through a grinding flat plate and a second auxiliary device. The machining efficiency and the machining precision are improved.

Description

Technical Field

[0001] The invention belongs to the technical field of component processing, and in particular relates to a two-piece thin-walled cylindrical complex component precision processing tool and a processing method. Background Art

[0002] When installing a high-precision gyroscope on the equipment, a two-part thin-walled cylindrical complex component is used. The component is made by combining two structural parts. Figure 1 As shown in the figure, the inner hole accuracy requirements of the two components are consistent, and the hole accuracy is very high. It is required that after the two parts are disassembled and then put together, the inner hole accuracy remains unchanged.

[0003] The traditional processing method of this component is to complete it by first processing separately and then combining them. The process flow is: A1 rough processing - B1 heat treatment - A2 semi-finishing processing - B2 heat treatment - A3 semi-finishing processing - B3 heat treatment - A4 finishing processing

[0004] In the traditional process, the process is divided into 4 rounds of processing, and heat treatment is performed in the middle of each round to eliminate stress. The main reason for gradually removing the excess in 4 times is that this component has a thin-walled structure and the inner cavity is not completed. The processing will produce large processing stress. After loosening the clamp, the component is deformed and released, making it difficult to ensure the accuracy of the component.

[0005] A1 rough machining: The process includes machining the outer arc surface of split parts 1 and 2, the B end surface perpendicular to the axial direction and the bottom surface parallel to the B end surface, the C end surface where the two split parts are in contact, the inner cavity notch and the circular surfaces of the inner cavity.

[0006] A1-1. Milling and boring: First, process the B surface and the parallel bottom surface of the split part 1 and split part 2 respectively, leaving a 1mm margin each, process the outer arc surface and the inner cavity notch of the two components respectively to meet the requirements, and process the C surface of the two components respectively, leaving a 1mm margin each.

[0007] A1-2, Lathe processing: Then use the caran to fix the two pieces on the lathe for inner hole processing, leaving a 1mm margin on each side of the inner hole;

[0008] B1 heat treatment: stress relief annealing.

[0009] A2 semi-finishing: The process includes machining the B end face and the bottom face parallel to it, the C end face and the inner cavity circles of the split parts 1 and 2.

[0010] A2-1. Milling and boring: First, process the B surface and the parallel bottom surface of the split part 1 and split part 2 respectively, leaving a 0.5mm margin each, and process the C surface of the two parts respectively, leaving a 0.5mm margin each;

[0011] A2-2, Turning: Use a calliper to fix two pieces on the lathe for inner hole processing, leaving a 1mm margin on each side of the inner hole;

[0012] B3 heat treatment: stress relief annealing.

[0013] A3 semi-finishing: The process includes machining the B end face and the bottom face parallel to it, the C end face and the inner cavity circles of the split parts 1 and 2:

[0014] A3-1. Milling and boring: First, process the B surface and the parallel bottom surface of split part 1 and split part 2 respectively, leaving a 0.2mm margin each, process the C surface of the two parts respectively, leaving a 0.1mm margin, and process the screw holes and countersunk holes on the C surface of the two parts to meet the requirements;

[0015] A3-2. Pliers processing: The fitter uses screws to fasten the two parts through the countersunk holes and screw holes.

[0016] A3-3, Turning: Then carry out inner hole processing on the lathe, leaving a 0.3mm margin on each side of the inner hole;

[0017] B3 heat treatment: stress relief annealing.

[0018] A4 finishing: The process includes machining the B end face and the bottom face parallel to it, the C end face and the inner cavity circle of split parts 1 and 2:

[0019] A4-1. Bench processing: Grind the C surfaces of the two pieces separately to meet the requirements; then fix the two pieces with screws and positioning pins;

[0020] A4-2, Grinding: Grind the B surface and the parallel bottom surface of the two pieces to meet the requirements;

[0021] A4-3. Boring process: Then finish bore the inner hole to meet the requirements.

[0022] Milling, boring and turning equipment are used in each round of processing, and vises, screw clamps and other clamping tools are used to clamp the components.

[0023] Traditional processing methods have the following problems:

[0024] 1. Since the structural parts are thin-walled, the inner wall structure is not a complete hole, there are two large openings in the middle, and the material is a casting (titanium alloy ZTC4), the stress generated during processing is large, the component deformation is large, and the accuracy is difficult to guarantee; in order to reduce the deformation of the component, the entire production process is divided into 4 rounds and the processing allowance is removed in batches, resulting in a very long entire processing cycle.

[0025] 2. The accuracy can meet the requirements just after processing on the equipment, but the components are deformed after loosening and clamping, resulting in poor accuracy;

[0026] 3. Since the requirements cannot be met in one processing, repeated trimming is required, which makes the entire processing cycle very long and easily leads to component scrapping.

[0027] 4. The processing level of the operator is very high. Summary of the invention

[0028] In view of the shortcomings of the prior art, the present invention proposes a two-part thin-walled cylindrical complex component precision machining tool and machining method that can improve production efficiency, improve machining accuracy, and reduce machining technical difficulty.

[0029] One of the above objects of the present invention is achieved by the following technical solution:

[0030] A two-part thin-walled cylindrical complex component precision machining tool, comprising a first auxiliary device and a second auxiliary device; the first auxiliary device is used to realize the alignment and snap-fit ​​internal clamping of the two parts of the component during rough turning and semi-finishing turning of the component; the second auxiliary device is used to realize the fixation of a single part of the component in a manner that the contact surface between the single part and the other part is exposed during fine machining of the component;

[0031] The first auxiliary device comprises a device body, a ball stud, a pressure plate, an arc-shaped hard baffle, an arc-shaped soft baffle, a soft filling block, and an end pressure plate; the device body is a cylinder provided with an inner hole, the shape of the inner hole of which is consistent with the outer surface shape of the thin-walled cylindrical complex component, and an axial limit platform for limiting the component is provided at one end of the inner hole; two mounting through holes are vertically provided at the inner cavity notches of the device body corresponding to the two outer bosses of the component, and the mounting through holes are composed of a stud connecting threaded hole located on the outside and a pressure plate mounting hole located on the inside; the inner ball head of the ball stud cooperates with the ball socket on the pressure plate to form a ball joint clamping assembly; a ball joint clamping assembly is installed in each mounting through hole on the device body, and a clamping contact is formed with the outer side surface of the outer boss of the component through the pressure plate; The arc-shaped soft baffle and the arc-shaped hard baffle are stacked inside and outside to form an arc-shaped baffle assembly; a group of arc-shaped baffle assemblies are respectively arranged on both sides between the embedding grooves of the two bosses of the component in the inner hole of the device body, and radial tightening screws are installed on the device body corresponding to the positions of the arc-shaped baffle assemblies on both sides, and the arc-shaped baffle assembly is pressed against the outer surface of the component by the screws; the shapes of the two soft filling blocks are consistent with the shapes of the inner grooves of the outer bosses on both sides of the component, and the two soft filling blocks are respectively embedded in the inner grooves on both sides of the component; the end face pressure plate is an annular pressure cover, the aperture of its inner hole is larger than the inner aperture of the component and smaller than the outer diameter of the component, and it is coaxially fixed to the end of the device body away from its axial limit platform by screws to achieve axial fixation of the component.

[0032] The second auxiliary device includes a device body, a ball stud and a pressure plate. The device body is a frame structure. The length of the frame inner cavity matches the axial size of the single-piece component. The width of the frame inner cavity matches the distance between the outer side surfaces of the two side bosses of the single-piece component. Positioning bosses corresponding to the upper end surfaces of the two bosses on the component are arranged at the upper part of the frame inner cavity close to the two sides along the long side direction; mounting holes are vertically arranged on the four side edges of the frame and on the two positioning bosses, and symmetrical handrails are arranged on both sides of the upper end of the frame; the inner ball head of the ball stud cooperates with the ball socket on the pressure plate to form a ball joint clamping assembly, and a ball joint clamping assembly is installed in each mounting hole. Through the ball joint clamping assembly, the component is fixed in the frame with the contact surface of the single-piece exposed downward.

[0033] The second objective of the present invention is achieved by the following technical solutions:

[0034] A processing method using the above-mentioned two-part thin-walled cylindrical complex component precision processing tooling comprises the following steps:

[0035] Step 1, rough machining: including machining the outer arc part of the split component 1 and the split component 2, the B end face perpendicular to the axial direction and the bottom face parallel to the B end face, the C face where the two split components are fastened and contacted, the inner cavity notch and each circular face of the inner cavity, wherein the first auxiliary device mentioned above is used to clamp and fix the components during machining of each circular face of the inner cavity;

[0036] Step 2, heat treating the component by stress relief annealing;

[0037] Step 3, semi-finishing: including processing the B end faces of the split component 1 and the split component 2 perpendicular to the axial direction and the bottom faces parallel to the B end faces, the C faces of the two split components in contact with each other, and the circular faces of the inner cavity, wherein the first auxiliary device mentioned above is used to clamp and fix the components during the processing of the circular faces of the inner cavity;

[0038] Step 4: heat-treating the components by stress relief annealing and high and low temperature stabilization treatment;

[0039] Step 5, finishing, including grinding the C surface of the split component 1 and the split component 2, using a grinding plate, and using the above-mentioned second auxiliary device to fix the components.

[0040] Furthermore, step 1 includes:

[0041] 1-1. Milling and boring processing: First, process the C surface of split parts 1 and 2 separately, leaving 1mm margin, process the B surface and the parallel bottom surface of split parts 1 and 2 separately, leaving 0.4mm margin respectively, process the outer arc surface of the two parts to meet the requirements, process the inner cavity groove to meet the requirements, process the screw holes and countersunk holes connecting the two parts on the C surface to meet the requirements, and finally process the C surfaces of the two parts separately, leaving 0.1mm margin respectively;

[0042] 1-2: Bench processing: Process the threaded holes on the split part 1 to meet the requirements, and tap the threads with M6 taps; use screws to fix the two components according to the component combination position in the figure: use hexagon socket screws M6×15 screws to fix the two parts through the position of the screw fastening holes shown in the figure, and finally tighten them with a unified torque wrench, and the torque is 9N.m;

[0043] 1-3: Grinding: Grind the B surface of the component and the lower surface parallel to it, remove 0.1mm each, and ensure that the parallelism of the two surfaces is no more than 0.02mm;

[0044] 1-4 Turning: Use a faceplate clamp to process the inner holes of the component combination on the lathe, leaving a 1mm margin on each side of the inner hole; processing parameters: spindle speed: 100r / min; lateral feed rate: F=0.3mm / r; longitudinal cutting depth 0.3mm.

[0045] Moreover, step 2 is specifically as follows: heating the furnace to 700° C., keeping the temperature for 2 hours, and then cooling the furnace.

[0046] Furthermore, step 3 includes:

[0047] 3.1. Grinding: Grind the C surface of split part 1 and split part 2 respectively: the removal amount is 0.05, and the flatness after grinding is not more than 0.006mm; Processing parameters: Grind the C surface on a zero-level grinding plate, using W20 boron carbide grinding material.

[0048] 3.2、Fix the two components with screws according to the assembly position of the components in the figure: Use hexagon socket screws M6×15 to fix the two parts through the position of the screw fastening holes shown in the figure. When tightening, use a unified torque wrench to fix it. The torque is 9N.m. Taper pin hole and install the taper pin;

[0049] 3.3. Grinding: Grind the component combination B surface and the bottom surface parallel to it, remove 0.2mm each, and ensure that the parallelism of the two surfaces is not greater than 0.008mm; Surface grinding machine processing parameters: Use Silicon carbide grinding wheel, grit size 46, grinding wheel linear speed 35m / S; vertical feed 0.003mm, lateral feed 10mm / time, longitudinal feed 18m / min;

[0050] 3.4. Turning: Use a faceplate clamp on the lathe to process the inner holes of the component combination, leaving a 0.3mm margin on each side of the inner hole; processing parameters: spindle speed: 150r / min; lateral feed rate: F=0.2mm / r; longitudinal cutting depth 0.2mm; the turning tool is a carbide forming tool.

[0051] Moreover, step 4 is specifically as follows: stress relief annealing: heating to 675°C with the furnace, keeping warm for 2 hours, and then cooling with the furnace; high and low temperature stabilization treatment: high temperature: heating to 100°C in 30 minutes, keeping warm for 2 hours, and air cooling to room temperature after taking out of the furnace; low temperature: cooling to -75°C in 30 minutes, keeping warm for 2 hours, and taking out of the box and placing at room temperature; the treatment is carried out in the order of hot, cold, hot and cold, and a total of 6 hot and cold cycles are carried out.

[0052] Moreover, in step 5, the precision of the grinding plate is zero level, and a cross groove with a width of 2×2 is processed on the plane of the grinding plate.

[0053] The advantages and positive effects of the present invention are:

[0054] 1. The present invention shortens the processing cycle of component finishing. By designing special auxiliary devices for grinding and turning, the accuracy of parts grinding and turning processes is improved. At the same time, the temperature of heat treatment is increased to remove the processing stress of parts more thoroughly. The deformation of parts in subsequent processing is easier to control. Therefore, the original four-round processing can be improved to three-round processing, which shortens the precision processing cycle of parts as a whole.

[0055] 2. The present invention reduces the processing deformation of components and improves the accuracy and reliability of components: by adjusting the annealing temperature of parts, the processing stress of parts can be removed more thoroughly, and by increasing high and low temperature stabilization treatment, the processing stability of parts is increased and the processing deformation is smaller; special auxiliary devices are used during grinding and turning, so that the grinding accuracy of the flatness of the joint surface of the two parts can be easily met, while improving the grinding efficiency; special devices are used during turning to enhance the rigidity of thin-walled parts, reduce the vibration of parts during processing, make it easy to ensure the accuracy of parts during fine processing, and improve the accuracy and reliability of parts.

[0056] The invention can be used for the processing and forming technology of thin-walled incomplete complex structural parts in the industries of aerospace, aviation, shipbuilding, precision instruments, etc., and has a very broad prospect for promotion and application. BRIEF DESCRIPTION OF THE DRAWINGS

[0057] Figure 1 It is a structural diagram of a two-part thin-walled cylindrical complex component according to the present invention, 1a is a split diagram, and 1b is a combined diagram;

[0058] Figure 2 It is a process flow chart of the precision machining method of two-part thin-walled cylindrical complex components of the present invention;

[0059] Figure 3 is a structural schematic diagram of the main part of the first auxiliary device of the present invention;

[0060] Figure 4 It is a schematic diagram of the appearance of the present invention in which two split components are placed in the first auxiliary device;

[0061] Figure 5 yes Figure 4 Schematic diagram after installing the end pressure plate;

[0062] Figure 6 is a cross-sectional schematic diagram of the two-part components of the present invention placed in the first auxiliary device;

[0063] Figure 7 It is a schematic structural diagram of the grinding plate used in the present invention;

[0064] Figure 8 8a is a schematic diagram of the structure of the second auxiliary device of the present invention, 8b is a stereoscopic diagram from a front view, 8c is a partial cross-sectional view at A, 8d is a partial cross-sectional view at B, and 8e is a partial cross-sectional view at C;

[0065] Fig. 9 It is a reference diagram of the present invention using the second auxiliary device for grinding finishing. DETAILED DESCRIPTION

[0066] The structure of the present invention is further described below with reference to the accompanying drawings and by way of examples. It should be noted that the present examples are descriptive rather than restrictive.

[0067] A precision machining method for two-part thin-walled cylindrical complex components, see Figure 1-Figure 9 The invention point is: it includes the following processing steps in sequence:

[0068] J1, rough machining;

[0069] R1, heat treatment;

[0070] J2, semi-finishing;

[0071] R2, heat treatment;

[0072] J3. Finishing.

[0073] See the processing flow Figure 2 The specific processing steps are as follows:

[0074] J1. Rough machining: The process includes machining the outer arc parts of split parts 1 and 2, the B end face perpendicular to their axial direction and the bottom face parallel to the B end face, the C surface where the two split parts are fastened and contacted, the inner cavity notch and the circular surfaces of the inner cavity.

[0075] J1-1, milling and boring processing: firstly process the C surface of split part 1 and split part 2 separately, leaving 1mm margin, process the B surface and the parallel bottom surface of split part 1 and split part 2 separately, leaving 0.4mm margin respectively, process the outer arc surface of the two parts to meet the requirements, process the inner cavity groove to meet the requirements, process the screw holes and countersunk holes connecting the two parts on the C surface to meet the requirements, and finally process the C surface of the two parts separately, leaving 0.1mm margin respectively;

[0076] Step 1-1: Process the C surface with a 1mm machining allowance, using a vertical machining center. Processing parameters: diameter Milling cutter, cutting depth a p＝ 0.5mm, feed speed F=150mm / min, speed 1000r / min;

[0077] Step 1-2: Use C surface as the reference to process B surface and the bottom surface parallel to B surface, leaving 1mm machining allowance, using vertical machining center for machining, machining parameters: diameter Milling cutter, cutting depth a p＝ 0.5mm, feed speed F=150mm / min, speed 1000r / min;

[0078] Step 1-3: Process the curved surface of the outer shape to meet the size requirements in the figure. Use a vertical machining center for processing. Processing parameters: ball cutter Depth of cut p＝ 0.05mm, feed speed F=100mm / min, speed 800r / min;

[0079] Step 1-4: Process the grooves in the inner cavity to meet the size requirements in the figure, using a vertical machining center. Processing parameters: diameter Milling cutter, cutting depth a p＝ 0.5mm, feed speed F=120mm / min, speed 1000r / min;

[0080] Step 1-5: Process the C surface with a 0.1mm margin; use a vertical machining center to process. Milling cutter, processing parameters: diameter Depth of cut p＝ 0.2mm, feed speed F=100mm / min, speed 1000r / min;

[0081] Step 1-6: Use a vertical machining center to process the bottom holes of the screw holes on the C surface of the split part 1 to meet the requirements. Processing parameters: drill bit Depth of cut p＝ 0.3mm, feed speed F = 30mm / min, speed 800r / min; process the through holes on the C surface of the split part 2 to the size shown in the figure, processing parameters: drill bit Depth of cutp＝ 0.3mm, feed speed F=30mm / min, speed 800r / min; milling cutter Depth of cut p＝ 0.3mm, feed speed F=20mm / min, speed 600r / min;

[0082] J1-2: Bench processing: Process the threaded holes on the split part 1 to meet the requirements, and tap the threads with M6 tap; use screws to fix the two components according to the component combination position in the figure: use hexagon socket screws M6×15 screws to fix the two parts through the position of the screw fastening holes shown in the figure, and finally tighten them with a unified torque wrench, and the torque is 9N.m.

[0083] J1-3: Grinding: Grind the B surface of the component and the lower surface parallel to it, removing 0.1mm each, and ensure that the parallelism of the two surfaces is no more than 0.02mm.

[0084] Use surface grinder for processing. Surface grinder processing parameters: Silicon carbide grinding wheel, grit size 60, grinding wheel linear speed 35m / S; vertical feed 0.005mm, lateral feed 10mm / time, longitudinal feed 18m / min;

[0085] J1-4 lathe: Then use the faceplate clamping on the lathe to process the inner hole of the component combination, leaving a 1mm margin on each side of the inner hole; ( The machining rotation diameter is greater than )

[0086] Processing parameters: spindle speed: 100r / min; lateral feed rate: F=0.3mm / r; longitudinal cutting depth 0.3mm;

[0087] The first auxiliary device is used during turning and clamping, see Figure 3-Figure 6 shown.

[0088] The structure of the first auxiliary device is as follows: a ball joint clamping mechanism consisting of a ball stud 2 and a pressure plate 3 is respectively installed on the left and right sides of the device body 1. The round ball of the ball stud and the inner spherical surface of the pressure plate have high requirements for the fit, requiring the ball pair contact rate of the two parts to be no less than 70%, and the axial clearance between the ball head and the concave ball cannot be greater than 0.003mm; an arc baffle assembly is respectively installed in front and behind the inner cavity of the device body. The arc baffle assembly consists of an arc hard baffle 8 and an arc soft baffle 9. The two parts are glued together. The arc hard baffle has a supporting function. The material is an aluminum plate. The arc soft baffle is a non-metallic material polyurethane (hardness 40A). The material is relatively soft and elastic, and grooves are processed on its surface to enhance the release of its deformation; the arc surface clamping screw is screwed into the screw hole 1.3 on the device body, and each arc surface has a total of 9.

[0089] Instructions for use of the first auxiliary device:

[0090] 1. Screw out the arc surface tightening screw 10 (indicated by the line position in the attached figure) about 2 mm; make the arc hard baffle assembly close to the inner wall of the device body;

[0091] 2. Unscrew each ball stud 3mm outward;

[0092] 3. Place the two-part component 5 into the inner cavity 1.2 of the device, then place the end face pressure plate 7 on the top of the component assembly, and tighten it with the end face fastening screws 6. Use a torque screwdriver when tightening, and use a torque of 5Nm.

[0093] 4. Place two soft fillers 4 into the inner cavity gaps 1.1 on the left and right sides of the component combination respectively. The plasticine needs to be well fitted to all sides of the gap. The second soft filler is plasticine.

[0094] 5. Then screw in the arc surface fastening screws on both sides of the arc surface, use a torque screwdriver when tightening, use a torque of 0.2Nm, so that the soft arc hard baffle can be close to the arc surface of the component combination without deforming the component combination. The use of soft materials can absorb the vibration of the component during processing and ensure that the accuracy of the component meets the requirements.

[0095] 6. Screw in the ball studs on the left and right sides of the device and tighten them with a torque screwdriver. Tighten with a torque of 0.1Nm. Tightening with a torque screwdriver of 0.1Nm is to prevent the top of the component from being deformed during tightening.

[0096] 7. Then install the entire device as a whole on the spindle of the lathe, clamp the end face and extension of the A side of the device, locate the inner hole of the component, and then process the inner hole of the component combination to meet the requirements.

[0097] J1 process analysis description:

[0098] When machining the inner hole after the components are assembled, a large deformation will occur. As a result, the original process needs to gradually remove the machining amount in multiple times. The clamping device designed for turning can strengthen the disadvantage of the thin wall of the component combination, suppress the deformation and extension of the component during processing, and after the two components are combined, the B surface and the bottom surface parallel to it are flat-ground, which also makes a good benchmark for turning and can reduce the deformation of clamping. After turning, the components are disassembled and assembled, and the deformation of the C surface of the two components is significantly reduced. The deformation of the inner hole is not more than 0.03, and the deformation of the C surface will not be more than 0.03mm. Therefore, leaving 0.1mm on the end face can ensure the subsequent processing allowance; the previous large amount of C surface allowance was because when turning the inner hole, the component deformation was large, which could reach 0.2mm, causing the C surface to be distorted, and more allowance was needed to ensure the subsequent processing, otherwise the component would be scrapped;

[0099] R1: Heat treatment; stress relief annealing.

[0100] The temperature was raised to 700°C in the furnace, kept at that temperature for 2 hours, and then cooled in the furnace.

[0101] The original heat treatment temperature was 650℃. In the subsequent processing, the deformation of the component was still large. In order to more thoroughly eliminate the internal stress of the component processing, the heat treatment temperature was increased to 700℃. This temperature was lower than the melting temperature of the casting, 950℃. Heating to this temperature will not reduce the strength of the component, and the effect of removing internal stress after heat treatment will be better.

[0102] J2: Semi-finishing

[0103] J2-1. Grinding process: Grind the C surface of split part 1 and split part 2 respectively: the removal amount is 0.05, and the flatness after grinding is not more than 0.006mm; Processing parameters: Grind the C surface on a zero-level grinding plate, using W20 boron carbide grinding material.

[0104] J2-2, Bench processing: Use screws to fix the two components according to the component combination position shown in the figure: Use hexagon socket screws M6×15 screws to fix the two parts through the position of the screw fastening holes shown in the figure. When tightening, use a uniform torque wrench to fix, and the torque is 9N.m. Taper pin hole and install the taper pin.

[0105] J2-3. Grinding: Grind the component combination B surface and the bottom surface parallel to it, removing 0.2mm each, and ensure that the parallelism of the two surfaces is not greater than 0.008mm.

[0106] Use surface grinder for processing. Surface grinder processing parameters: Silicon carbide grinding wheel, grit size 46, grinding wheel linear speed 35m / S; vertical feed 0.003mm, lateral feed 10mm / time, longitudinal feed 18m / min;

[0107] J2-4, Turning: Use a faceplate clamp to process the inner holes of the component assembly on a lathe, leaving a 0.3mm margin on each side of the inner hole; ( The machining rotation diameter is greater than ), a clamping workpiece positioning device is used during turning.

[0108] Processing parameters: spindle speed: 150r / min; lateral feed rate: F=0.2mm / r; longitudinal cutting depth 0.2mm; the turning tool is a carbide forming tool.

[0109] J2 process optimization analysis description:

[0110] Optimized areas compared to the original process: The C surface of split parts 1 and 2 is ground, and the removal amount is 0.05mm; the current allowance is 0.05mm each, which is much less than the flow rate of the traditional process; the allowance of the traditional process is 0.5mm each; reason: because the flat grinding of the B surface of the component combination is added, a high-precision benchmark is provided for semi-finishing machining, and the deformation of clamping is also reduced; and the clamping workpiece positioning device is used for clamping during machining, which greatly reduces the deformation of the processed component. After the improved process, the C surface of the two components is very small, and the inner hole is basically a full circle when the component combination is processed. The removal amount of the inner hole is uniform and small, causing little deformation of the component. Therefore, the original two semi-finishing processes are combined into one semi-finishing process.

[0111] R2: Heat treatment; stress relief annealing + high and low temperature stabilization treatment.

[0112] Stress relief annealing: heat up to 675℃ with the furnace, keep warm for 2 hours, and then cool with the furnace. High and low temperature stabilization treatment: high temperature: heat up to 100℃ in 30 minutes, keep warm for 2 hours, and air cool to room temperature after taking out of the furnace; low temperature: cool down to -75℃ in 30 minutes, keep warm for 2 hours, and put it out of the box to room temperature; process in the order of hot, cold, hot, cold, etc., for a total of 6 hot and cold cycles.

[0113] The original heat treatment temperature was 625℃, and now it is 675℃. The stress removal effect will be better, and this temperature will not reduce the strength of the component. After the stress relief annealing, high and low temperature stable cycle treatment is added to impact the component through high and low temperature cross temperature, so that the stability of the component is better, and the accuracy is easier to ensure during fine processing.

[0114] J3. Grinding: Process the C surface of split parts 1 and 2. The flatness of the C surface of the two parts is required to be no greater than 0.003mm.

[0115] Place split parts 1 and 2 on a workbench. A grinding plate, which is the second auxiliary device used for grinding, is also placed on the workbench. In addition, grinding sand (borax W20), white kerosene, non-woven fabric, medical cotton, gasoline and a brush are also required.

[0116] Grinding plate 11 see Figure 7 As shown, the precision of the grinding plate is zero level, and a cross groove with a width of 2×2 is processed on the plane of the grinding plate. The function of the groove is to facilitate the removal of abrasives during grinding and prevent the grinding component from having inconsistent removal amounts at the periphery and center, which affects the overall flatness accuracy of the component.

[0117] Secondary auxiliary device used during grinding, see Figure 8As shown. The device body 12 is a frame, and the device body is a frame structure. The length of the inner cavity of the frame matches the axial size of the single split component, and the width of the inner cavity of the frame matches the distance between the outer side surfaces of the bosses on both sides of the single split component. Positioning bosses 12.1 corresponding to the upper end surfaces of the two bosses on the component are arranged at the upper part of the inner cavity of the frame near the two sides along the long side direction; mounting through holes are vertically arranged on the four side edges of the frame and the two positioning bosses, and symmetrical handrails 13 are arranged on both sides of the upper end of the frame; the inner ball head of the ball stud cooperates with the ball socket on the pressure plate to form a ball joint clamping assembly, and a ball joint clamping assembly is installed in each mounting through hole. Through the ball joint clamping assembly, the component is fixed in the frame in a manner that the contact surface of the single split component is exposed downward.

[0118] There are 4 ball joint clamping assemblies installed on the front and rear sides of the frame. The ball joint clamping assembly (see the cross-sectional view at A) is a clamping mechanism composed of a ball stud and a pressure plate. The round ball of the ball stud and the inner spherical surface of the pressure plate have high requirements for matching, requiring the ball pair contact rate of the two pieces to be no less than 70%, and the axial clearance between the ball head and the concave ball cannot be greater than 0.003mm; There are 2 ball joint clamping assemblies installed on the left and right sides of the frame. The ball joint clamping assembly (see the cross-sectional view at B) is a clamping mechanism composed of a ball stud and a pressure plate. The round ball of the ball stud The inner spherical surface of the ball and the pressure plate has high requirements for matching, requiring the contact rate of the ball pair of the two pieces to be no less than 70%, and the axial clearance between the ball head and the concave ball cannot be greater than 0.003mm; 3 ball joint clamping assemblies are installed on both sides of the upper part of the frame. The ball joint clamping assembly (see the cross-sectional view at C) is a clamping mechanism composed of a ball stud and a pressure plate. The ball of the ball stud and the inner spherical surface of the pressure plate have high requirements for matching, requiring the contact rate of the ball joint pair of the two pieces to be no less than 70%, and the axial clearance between the ball head and the concave ball cannot be greater than 0.003mm. Explanation of the use of ball joint pairs for ball head screws and pressure plates: Since the flatness of each surface of the outer shape of split parts 1 and split parts 2 cannot reach the ideal 0mm, the actual flatness of each surface can reach 0.2mm; if only the screw is used to tighten directly, the contact position is the screw head, the contact area is small, and the screw will produce large local deformation after being tightened at normal force, resulting in increased deformation of the component clamping, affecting the processing accuracy. Therefore, a ball joint structure is adopted, and the pressure plate presses the side of the component. The end face of the pressure plate is large, and the contact area with the component is large. Because of the ball joint pair, when the center line of the screw hole is not perpendicular to the side of the component, the ball joint plays a role, which not only ensures the complete structure of the end face of the pressure plate and the side of the component, but also applies the clamping force to the side of the component vertically through the ball joint pair to ensure the compression and compaction of the side of the component. When the screw is screwed in, the pressure plate can rotate slightly with the ball head screw, so that the end face of the pressure plate can reliably contact the component. The external thread of the ball head screw adopts a fine thread pitch of 0.75, and the screw hole on the device is also M6×0.75, which strengthens the self-locking function of the thread to prevent the screw from loosening after tightening.

[0119] Although the embodiments and drawings of the present invention are disclosed for illustrative purposes, those skilled in the art will appreciate that various substitutions, changes and modifications are possible without departing from the spirit and scope of the present invention and the appended claims. Therefore, the scope of the present invention is not limited to the contents disclosed in the embodiments and drawings.

Claims

1. A two-part thin-walled cylindrical complex component precision machining tool, characterized by: The invention comprises a first auxiliary device and a second auxiliary device; the first auxiliary device is used to realize the alignment and snap-fit ​​internal fixing of the two parts of the component during the rough turning and semi-finishing turning of the component; the second auxiliary device is used to realize the fixing of a single part of the component in a manner that the contact surface between the single part and the other part is exposed during the fine machining of the component; The first auxiliary device comprises a device body, a ball stud, a pressure plate, an arc-shaped hard baffle, an arc-shaped soft baffle, a soft filling block, and an end pressure plate; the device body is a cylinder provided with an inner hole, the shape of the inner hole of which is consistent with the outer surface shape of the thin-walled cylindrical complex component, and an axial limit platform for limiting the component is provided at one end of the inner hole; two mounting through holes are vertically provided at the inner cavity notches of the device body corresponding to the two outer bosses of the component, and the mounting through holes are composed of a stud connecting threaded hole located on the outside and a pressure plate mounting hole located on the inside; the inner ball head of the ball stud cooperates with the ball socket on the pressure plate to form a ball joint clamping assembly; a ball joint clamping assembly is installed in each mounting through hole on the device body, and a clamping contact is formed with the outer side surface of the outer boss of the component through the pressure plate; The arc-shaped soft baffle and the arc-shaped hard baffle are stacked inside and outside to form an arc-shaped baffle assembly; a group of arc-shaped baffle assemblies are respectively arranged on both sides between the embedding grooves of the two bosses of the component in the inner hole of the device body, and radial tightening screws are installed on the device body at positions corresponding to the arc-shaped baffle assemblies on both sides, and the arc-shaped baffle assembly is pressed by the screws so that the arc-shaped baffle assembly is pressed against the outer surface of the component; the shapes of the two soft filling blocks are consistent with the shapes of the inner grooves of the outer bosses on both sides of the component, and the two soft filling blocks are respectively embedded in the inner grooves on both sides of the component; the end face pressure plate is an annular pressure cover, the aperture of its inner hole is larger than the inner aperture of the component and smaller than the outer diameter of the component, and it is coaxially fixed to the end of the device body away from its axial limit platform by screws to achieve axial fixation of the component; The second auxiliary device includes a device body, a ball stud and a pressure plate. The device body is a frame structure. The length of the frame inner cavity matches the axial size of the single-piece component. The width of the frame inner cavity matches the distance between the outer side surfaces of the two side bosses of the single-piece component. Positioning bosses corresponding to the upper end surfaces of the two bosses on the component are arranged at the upper part of the frame inner cavity close to the two sides along the long side direction; mounting holes are vertically arranged on the four side edges of the frame and on the two positioning bosses, and symmetrical handrails are arranged on both sides of the upper end of the frame; the inner ball head of the ball stud cooperates with the ball socket on the pressure plate to form a ball joint clamping assembly, and a ball joint clamping assembly is installed in each mounting hole. Through the ball joint clamping assembly, the component is fixed in the frame with the contact surface of the single-piece exposed downward.

2. A processing method using the two-part thin-walled cylindrical complex component precision processing tooling according to claim 1, characterized in that: The steps include: Step 1, rough machining: including machining the outer arc part of the split component 1 and the split component 2, the B end face perpendicular to the axial direction and the bottom face parallel to the B end face, the C face where the two split components are fastened and contacted, the inner cavity notch and each circular face of the inner cavity, wherein the first auxiliary device is used to clamp and fix the components during machining of each circular face of the inner cavity; Step 2, heat treating the component by stress relief annealing; Step 3, semi-finishing: including processing the B end faces of the split component 1 and the split component 2 perpendicular to the axial direction and the bottom faces parallel to the B end faces, the C faces of the two split components in contact with each other, and the circular faces of the inner cavity, wherein the first auxiliary device mentioned above is used to clamp and fix the components during the processing of the circular faces of the inner cavity; Step 4: heat-treating the components by stress relief annealing and high and low temperature stabilization treatment; Step 5, finishing, including grinding the C surface of the split component 1 and the split component 2, using a grinding plate, and using a second auxiliary device to fix the components.

3. The processing method according to claim 2 using the two-piece thin-walled cylindrical complex component precision processing tooling according to claim 1 is characterized in that: Step 1 includes: 1-1. Milling and boring processing: First, process the C surface of split parts 1 and 2 separately, leaving 1mm margin, process the B surface and the parallel bottom surface of split parts 1 and 2 separately, leaving 0.4mm margin respectively, process the outer arc surface of the two parts to meet the requirements, process the inner cavity groove to meet the requirements, process the screw holes and countersunk holes connecting the two parts on the C surface to meet the requirements, and finally process the C surfaces of the two parts separately, leaving 0.1mm margin respectively; 1-2: Bench processing: Process the threaded holes on the split part 1 to meet the requirements, and tap the threads with M6 taps; use screws to fix the two components according to the component combination position in the figure: use hexagon socket screws M6×15 screws to fix the two parts through the position of the screw fastening holes shown in the figure, and finally tighten them with a unified torque wrench, and the torque is 9N.m; 1-3: Grinding: Grind the B surface of the component and the lower surface parallel to it, remove 0.1mm each, and ensure that the parallelism of the two surfaces is no more than 0.02mm; 1-4 Turning: Use a faceplate clamp to process the inner holes of the component combination on the lathe, leaving a 1mm margin on each side of the inner hole; processing parameters: spindle speed: 100r / min; lateral feed rate: F=0.3mm / r; longitudinal cutting depth 0.3mm.

4. The processing method according to claim 2 using the two-part thin-walled cylindrical complex component precision processing tooling according to claim 1 is characterized in that: Step 2 is specifically as follows: heating the furnace to 700° C., keeping the temperature for 2 hours, and then cooling the furnace.

5. The processing method according to claim 2 using the two-part thin-walled cylindrical complex component precision processing tooling according to claim 1 is characterized in that: Step 3 includes: 3.

1. Grinding: Grind the C surface of split part 1 and split part 2 respectively: the removal amount is 0.05, and the flatness after grinding is not more than 0.006mm; Processing parameters: Grind the C surface on a zero-level grinding plate, using W20 boron carbide grinding material; 3.2、Fix the two components with screws according to the assembly position of the components in the figure: Use hexagon socket screws M6×15 to fix the two parts through the position of the screw fastening holes shown in the figure. When tightening, use a unified torque wrench to fix it. The torque is 9N.m. Taper pin hole and install the taper pin; 3.3 Grinding: Grind the component combination B surface and the bottom surface parallel to it, remove 0.2mm each, and ensure that the parallelism of the two surfaces is not greater than 0.008mm; Surface grinding machine processing parameters: Use Silicon carbide grinding wheel, grit size 46, grinding wheel linear speed 35m / S; vertical feed 0.003mm, lateral feed 10mm / time, longitudinal feed 18m / min; 3.

4. Turning: Use a faceplate clamp on the lathe to process the inner holes of the component combination, leaving a 0.3mm margin on each side of the inner hole; processing parameters: spindle speed: 150r / min; lateral feed rate: F=0.2mm / r; longitudinal cutting depth 0.2mm; the turning tool is a carbide forming tool.

6. The processing method according to claim 2 using the two-part thin-walled cylindrical complex component precision processing tooling according to claim 1 is characterized in that: Step 4 is specifically as follows: stress relief annealing: heating to 675°C with the furnace, keeping warm for 2 hours, and then cooling with the furnace; high and low temperature stabilization treatment: high temperature: heating to 100°C in 30 minutes, keeping warm for 2 hours, and air cooling to room temperature after taking out of the furnace; low temperature: cooling to -75°C in 30 minutes, keeping warm for 2 hours, and taking out of the box and placing it at room temperature; the treatment is carried out in the order of hot and cold, and a total of 6 hot and cold cycles are carried out.

7. The processing method according to claim 2 using the two-part thin-walled cylindrical complex component precision processing tooling according to claim 1 is characterized in that: In step 5, the precision of the grinding plate is zero level, and a cross groove with a width of 2×2 is processed on the plane of the grinding plate.

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