A processing technology for thin-wall sealing ring

Abstract

The present invention discloses a thin-walled sealing ring processing technology, which belongs to the field of aerospace parts processing technology. The process includes the following steps: step one, material preparation; step two, rough turning of blanks; step three, ultrasonic testing; step four, turning the shape and boring holes: clamping the outer circle of the part to turn the end face and boring the inner hole; step five, turning the end face and outer circle: supporting the inner hole of the part to turn the outer circle and end face, and processing its outer circle into a step shape; step six, heat treatment: remove the stress generated by the previous machining process; step seven, washing; step eight, spraying silver-copper coating; step nine, removing the silver-copper coating flash; step ten, fine turning the end face; step eleven, fine turning the shape and inner cavity; step twelve, fine turning the shape and milling holes; step thirteen, chamfering and deburring. Before fine machining the parts, the parts are first heat treated to remove the stress generated by the previous machining process, so as to avoid the stress generated by the previous machining process being released during the subsequent processing process and causing the wall of the thin-walled sealing ring to deform.

Description

Technical Field

[0001] The invention relates to a thin-wall sealing ring processing technology, belonging to the technical field of aerospace parts processing. Background Art

[0002] In the field of aerospace technology, structural parts used to seal and protect important components in high temperature and high speed environments need to maintain good mechanical properties and sealing properties in high temperature environments, as well as good stability performance under high speed conditions. As an aerospace structural part, the thin-walled sealing ring has a structure such as Figures 1 to 4 As shown, it has the functions of supporting, connecting, sealing, and protecting. Its structure is complex, and the outer circle size precision requirements are high. It is fitted with the assembly parts by interference, which effectively realizes its good sealing performance. Its inner cavity is sprayed with plasma silver-copper coating and has high dimensional precision requirements. It can support the high-speed rotation of shaft rotors and play a lubricating role. There are 4 square bosses at the ring end, and the ring wall is accompanied by multiple holes that are not perpendicular to the center axis of the thin-walled sealing ring. It is connected and tightened with the corresponding accessories during assembly to achieve good torsion resistance. In order to ensure that the thin-walled sealing ring has high supporting and protective performance, its material is selected from the precipitation-strengthened nickel-based high-temperature alloy GH4169 with a higher strength grade. However, due to the thin ring wall of the thin-walled sealing ring, the thinnest part is only 2.1mm, and the material hardness is relatively hard, the thin-walled sealing ring is prone to deformation during processing, resulting in a low yield rate.

[0003] A Chinese patent document with publication number CN112756912A discloses a thin-walled sealing ring processing system and processing method, which includes the following steps: Step S1: Obtain a blank, rough-turn the outer circumferential surface, and form a large end face clamping edge and a small end face clamping edge; Step S2: Rough-turn the inner circumferential surface near the large end face, so that an axial step is formed on the inner circumferential surface near the small end face; Step S3: Clamp the outer side of the small end face clamping edge and the axial step of the inner circumferential surface near the small end face, and rough-turn the large end face groove and the small end face groove; Step S4: Clamp the two axial end faces of the part, and mill the large end face boss and the small end face boss; Step S5: Fine-turn the process benchmark; Step S6: Fine-turn to the target size; Step S7: Wire cutting to divide the part into two parts. This method eliminates the stabilization processing step in the prior art, shortens the part processing cycle, optimizes the process route, and processes all shapes and dimensions in one process. In addition, by adjusting the processing sequence of CNC milling and CNC turning, it effectively prevents the deformation of the dimensions in the CNC turning process after CNC milling, which causes the parts to be out of tolerance. At the same time, it optimizes the tool path of the CNC turning program to reduce part deformation.

[0004] However, during the processing of thin-walled sealing rings, the stress generated in the previous machining process will be released in the subsequent processing process, causing the wall of the thin-walled sealing ring to deform, further resulting in a decrease in the yield of the thin-walled sealing ring. Summary of the invention

[0005] In order to solve the above technical problems, the present invention provides a thin-wall sealing ring processing technology.

[0006] The present invention is achieved through the following technical solutions:

[0007] A thin-wall sealing ring processing technology comprises the following steps:

[0008] Step 1: Material preparation: prepare the part blank, which is a cylindrical part;

[0009] Step 2: Rough turning of the blank: Rough turning of the two end faces, outer circle and inner hole of the parts to remove the surface oxide scale;

[0010] Step 3: Ultrasonic testing: Perform ultrasonic testing on the parts to ensure that there are no bubbles or cracks in the internal material structure of the parts;

[0011] Step 4: Turning the outer shape and boring the hole: Clamp the outer circle of the part to turn the end face, bore the inner hole, and turn the coating ring groove in the inner hole to the target size;

[0012] Step 5: Turning the end face and outer circle: Using the end face of the part processed in step 4 as a support, support the inner hole of the part to turn the outer circle and end face, and process its outer circle into a step shape;

[0013] Step 6: Heat treatment: Heat treat the parts to remove the stress generated by the previous machining process;

[0014] Step 7: Washing: Clean the parts;

[0015] Step 8, spraying silver-copper coating: plasma spraying silver-copper coating in the coating ring groove;

[0016] Step 9: Remove the silver-copper coating flash: Grind and remove the silver-copper coating flash;

[0017] Step 10: Finish turning the end face: Use soft three-jaw clamping to turn the outer circle of the part on the CNC lathe to turn the end face of the outer circle;

[0018] Step 11: Finish turning the shape and inner cavity: Use a special CNC lathe to clamp the parts, and align the end face of the parts to a runout of no more than 0.02mm. Finish turn the end face of the parts, bore the inner hole, and chamfer the parts on a CNC lathe to turn the inner cavity size of the parts to the target size.

[0019] Step 12: Finish turning the shape and milling holes: Use a special milling machine to clamp the parts, finish turning the outer circle of the parts on a five-axis turning and milling machining center, drill all vertical holes and non-vertical holes on the outer circle of the parts, mill the four square bosses on the outer circle of the end face of the parts, and process the outer dimensions of the parts to the target dimensions;

[0020] Step 13: chamfering and deburring: chamfer all the holes on the parts and remove the burrs on the holes to obtain a thin-walled sealing ring;

[0021] The special milling machine tool in step 12 comprises a positioning shaft and a clamping cover, the clamping cover is coaxially arranged with the positioning shaft and is detachably connected to one end of the positioning shaft through a connecting piece;

[0022] The positioning shaft comprises a coaxially arranged clamping section, a supporting section and a positioning section, one end of the supporting section is connected to one end of the clamping section, and the other end is connected to one end of the positioning section, and the diameter of the supporting section is larger than the diameter of the clamping section and the diameter of the positioning section;

[0023] A plurality of positioning bosses are provided on the positioning section along the circumferential direction, and a threaded hole B is coaxially provided on one end of the positioning section away from the supporting section; the outer cylindrical surface of the positioning boss is adapted to the inner cylindrical surface except for the silver-copper coating, and the outer cylindrical surface of the positioning boss is fitted with the junction of the inner cavity material body of the part and the silver-copper coating to reduce the contact area between the positioning shaft and the silver-copper coating.

[0024] The blank in step 1 is a ring forging after solution treatment and aging treatment, and the material is precipitation-strengthened nickel-based high-temperature alloy GH4169;

[0025] After step 5 is completed, the size of the parts is inspected according to the drawings;

[0026] After step 6 is completed, the parts are subjected to fluorescence inspection to ensure that there are no defects on the surface of the parts;

[0027] When grinding and removing the flash of the silver-copper coating in step nine, the flash is removed by grinding from the inner hole of the part to the outside.

[0028] The method for heat treating the parts in step 6 is: placing the parts in a vacuum furnace and heating them to 520°C~570°C, keeping them warm for 2h~4h, and controlling the vacuum degree in the vacuum furnace to below 13Pa, then filling the vacuum furnace with argon gas and turning on the circulating fan to cool the parts until the pressure in the vacuum furnace rises to (1~1.4)×10 5 Pa.

[0029] The special lathe tooling in step eleven comprises a positioning plate and a plurality of clamping components evenly arranged on the positioning plate.

[0030] The positioning plate is made of 45# steel with a hardness of HRC35-40. A plurality of positioning holes are evenly distributed on the positioning plate, and threaded holes A are evenly distributed with the same number as the clamping components. A blind hole A is coaxially provided on the end surface of one end of the positioning plate, and a reference blind hole is provided on the end surface of the other end, and a tool-releasing blind hole is coaxially provided on the bottom surface of the reference blind hole.

[0031] The end surface of the positioning plate with the blind hole A is taken as the reference plane A. The parallelism of the bottom surface of the reference blind hole relative to the reference plane A is 0.01 mm, and the verticality of the hole wall of the reference blind hole relative to the reference plane A is 0.01 mm.

[0032] The clamping assembly includes a pressure plate and a screw. The pressure plate is made of 45 steel with a hardness of HRC35-40. The pressure plate is L-shaped, one end of which is an arc surface, and an elongated hole is provided on the pressure plate. One end of the screw passes through the elongated hole on the pressure plate and is threadedly connected to the positioning plate.

[0033] The method of clamping parts using a special lathe tool in step 11 is as follows: using the end face of the large outer circle end finely turned in step 10 as a support and the outer circle of the large end as a reference, insert the large end of the part into the reference blind hole on the positioning plate, and then evenly tighten the screws in each clamping assembly to press the pressure plate tightly on the step surface machined on the outer circle of the part in step 5.

[0034] The positioning shaft and the clamping cover are made of 45# steel with a hardness of HRC35-40;

[0035] The parallelism of the two end surfaces of the supporting section is 0.01 mm, and the coaxiality of the outer cylindrical surface of the positioning boss relative to the outer cylindrical surface of the clamping section is 0.01 mm;

[0036] A sink is coaxially provided on the end surface of the clamping cover close to the positioning shaft, and a through hole is coaxially provided on the clamping cover. A plurality of lightening holes are evenly distributed on the clamping cover.

[0037] The connecting piece is a screw A, and one end of the connecting piece passes through the through hole on the clamping cover and is threadedly connected with the threaded hole B on the positioning shaft.

[0038] The method of clamping the parts using a special milling machine tool in step 12 is: using the inner hole of the silver-copper coating as a reference, inserting the positioning section on the positioning shaft into the part, and ensuring that the large end of the part is close to the supporting section, and then connecting the clamping cover to the positioning shaft through the connecting piece and tightening it.

[0039] The beneficial effects of the present invention are:

[0040] 1. Before finishing the parts, heat treat the parts first to remove the stress generated by the previous machining process to avoid the stress generated by the previous machining process being released during the subsequent processing process and causing deformation of the ring wall of the thin-walled sealing ring.

[0041] 2. The silver-copper coating process is set after the heat treatment process to avoid the stress generated by the previous machining process being released during the subsequent processing process, which may cause the silver-copper coating to deform or even fall off, thereby ensuring the spraying quality of the silver-copper coating; the silver-copper coating process is set before the finishing process to effectively utilize the machining allowance in the inner cavity of the part to remove the flash of the silver-copper coating by grinding.

[0042] 3. When the special lathe tooling clamps the parts, the end face of the large outer circle on the part is used as the support, and the large end outer circle is used as the reference. The step surface on the outer circle of the part is pressed by the pressure plate to achieve part clamping, which effectively reduces the force on the part and makes the force on the part uniform. It significantly reduces the deformation of the part caused by extrusion during the processing, improves the processing stability of the part, and can reduce the risk of excessive deformation of the part.

[0043] 4. When the special milling machine tool clamps the parts, one end face of the part is used as the support, and the inner hole of the silver-copper coating is used as the reference. The other end face of the part is pressed by the clamping cover to achieve part clamping, which effectively reduces the force on the parts and makes the force on the parts uniform. It significantly reduces the deformation of the parts caused by extrusion during the processing, improves the processing stability of the parts, and can reduce the risk of excessive deformation of the parts. BRIEF DESCRIPTION OF THE DRAWINGS

[0044] Figure 1 It is a schematic diagram of the main structure of the thin-wall sealing ring of the present invention;

[0045] Figure 2 for Figure 1 Sectional view along DD;

[0046] Figure 3 for Figure 1 Sectional view along EE;

[0047] Figure 4 It is a schematic diagram of the three-dimensional structure of the thin-wall sealing ring of the present invention;

[0048] Figure 5 It is a schematic structural diagram of the blank of the present invention;

[0049] Figure 6 This is a schematic diagram of the structure of the parts after the second step of the present invention is completed;

[0050] Figure 7 This is a schematic diagram of the structure of the parts after the fourth step of the present invention is completed;

[0051] Figure 8 This is a schematic diagram of the structure of the parts after the fifth step of the present invention is completed;

[0052] Fig. 9 This is a schematic diagram of the structure of the parts after the eighth step of the present invention is completed;

[0053] Fig.10 This is a schematic diagram of the structure of the parts after the step eleven of the present invention is completed;

[0054] Fig.11 This is a schematic diagram of the structure of the parts after the step thirteen of the present invention is completed;

[0055] Fig.12 This is a schematic diagram of the structure of the special lathe tooling of the present invention after clamping the parts;

[0056] Fig.13 A partial view of the positioning plate of the present invention;

[0057] Fig.14 It is a structural schematic diagram of the positioning plate of the present invention;

[0058] Fig.15 It is a schematic diagram of the main structure of the pressing plate of the present invention;

[0059] Fig.16 is a cross-sectional view of a pressing plate of the present invention;

[0060] Fig.17 It is a schematic diagram of the structure after the special milling machine tool of the present invention clamps the parts;

[0061] Fig.18 It is a structural schematic diagram of the positioning shaft of the present invention;

[0062] Fig.19 It is a schematic structural diagram of the compression cover of the present invention.

[0063] In the figure: 1-thin-wall sealing ring, 10-square boss, 11-coated ring groove, 12-silver-copper coating, 13-non-vertical hole, 14-vertical hole, 2-special lathe tooling, 20-positioning plate, 200-positioning hole, 201-threaded hole A, 202-blind hole A, 203-reference blind hole, 204-knife blind hole, 205-reference surface A, 21-pressing plate, 210-elongated hole, 22-screw, 3-special milling machine tooling, 30-positioning shaft, 300-clamping section, 301-supporting section, 302-positioning section, 303-positioning boss, 304-threaded hole B, 31-pressing cover, 310-sunk table, 311-through hole, 312-lightening hole, 32-connector. DETAILED DESCRIPTION

[0064] The technical solution of the present invention is further described below, but the scope of protection claimed is not limited to the description.

[0065] like Figures 1 to 19 As shown, a thin-wall sealing ring processing technology described in the present invention includes the following steps:

[0066] Step 1: Material preparation: Prepare the part blank, which is a cylindrical part.

[0067] Step 2: Rough turning of blanks: Rough turning of both end faces, outer circle and inner hole of parts to remove the surface oxide scale. Figure 6As shown, the black oxide scale on the surface of the part is removed to facilitate better ultrasonic testing of the part in the subsequent process. At the same time, a positioning and clamping reference surface is processed for the subsequent process.

[0068] Step 3: Ultrasonic testing: Perform ultrasonic testing on the parts to ensure that there are no bubbles or cracks in the internal material structure of the parts.

[0069] Step 4: Turning the outer shape and boring the hole: Clamp the outer circle of the part to turn the end face, bore the inner hole, and turn the coating ring groove 11 in the inner hole to the target size, such as Figure 7 shown.

[0070] Step 5: Turn the end face and outer circle: Use the end face of the part processed in step 4 as a support to support the inner hole of the part and turn the outer circle and end face, and process the outer circle into a step shape. Figure 8 As shown, the step surface machined on the outer circle of the part will serve as the positioning and clamping reference surface for the special lathe tooling 2 in step eleven.

[0071] Step 6: Heat treatment: Heat treatment is performed on the parts to remove the stress generated by the previous machining process, so as to avoid the stress generated by the previous machining process being released during the subsequent processing process and causing the ring wall of the thin-walled sealing ring 1 to deform.

[0072] Step 7: Washing: Clean the parts.

[0073] Step 8: Spraying silver-copper coating: Plasma spraying silver-copper coating 12 in coating ring groove 11, such as Fig. 9 shown.

[0074] Step 9. Remove the burrs of the silver-copper coating: Grind and remove the burrs of the silver-copper coating 12.

[0075] Step 10: Finish turning the end face: Use soft three-jaw clamping to turn the outer circle of the part on the CNC lathe to enlarge the outer circle end face. This will be the reference for finishing the inner cavity of the part in the subsequent process.

[0076] Step 11: Finish turning the shape and inner cavity: Use a special CNC lathe to clamp the parts, and find that the end face runout of the parts is no more than 0.02mm. Finish turn the end face of the parts, bore the inner hole, and chamfer the parts on a CNC lathe to turn the inner cavity size of the parts to the target size, such as Fig.10 shown.

[0077] Step 12, fine turning of the shape and milling of holes: Use a special milling machine tool 3 to clamp the part, fine turn the outer circle of the part on the five-axis turning and milling machining center, drill all vertical holes 14 and non-vertical holes 13 on the outer circle of the part, mill the four square bosses 10 on the outer circle of the end face of the part, and process the outer dimensions of the part to the target size, such as Fig.11 shown.

[0078] Step 13: Chamfering and deburring: Chamfer all the holes on the parts and remove the burrs on the holes to obtain a thin-walled sealing ring 1.

[0079] The special milling machine tool 3 in step twelve comprises a positioning shaft 30 and a clamping cover 31, wherein the clamping cover 31 is coaxially arranged with the positioning shaft 30 and is detachably connected to one end of the positioning shaft 30 via a connecting piece 32;

[0080] The positioning shaft 30 comprises a coaxially arranged clamping section 300, a supporting section 301 and a positioning section 302, one end of the supporting section 301 is connected to one end of the clamping section 300, and the other end is connected to one end of the positioning section 302, and the diameter of the supporting section 301 is larger than the diameter of the clamping section 300 and the diameter of the positioning section 302;

[0081] A plurality of positioning bosses 303 are circumferentially provided on the positioning section 302, and a threaded hole B304 is coaxially provided on one end of the positioning section 302 away from the supporting section 301; the outer cylindrical surface of the positioning boss 303 is adapted to the inner cylindrical surface of the silver-copper coating 12, and the outer cylindrical surface of the positioning boss 303 is in contact with the junction of the inner cavity material body of the part and the silver-copper coating 12, so as to reduce the contact area between the positioning shaft 30 and the silver-copper coating 12.

[0082] The blank in step 1 is a ring forging after solution treatment and aging treatment, and the material is precipitation-strengthened nickel-based high-temperature alloy GH4169;

[0083] After step 5 is completed, the size of the parts is inspected according to the drawings;

[0084] After step 6 is completed, the parts are subjected to fluorescence inspection to ensure that there are no defects on the surface of the parts;

[0085] When grinding and removing the flash of the silver-copper coating 12 in step nine, the flash is removed from the inner hole of the part to the outside. The blank in step one is a ring forging that has been subjected to solution treatment and aging treatment, such as Figure 5 As shown, one is to save materials, and the other is that the internal structure of the forging is much better than that of the bar, and it can have good stability in a high temperature environment; the material of the billet is precipitation-strengthened nickel-based high-temperature alloy GH4169, which has a higher hardness after aging treatment. When grinding to remove the flash of the silver-copper coating 12, the flash must be removed from the inner hole of the part in the direction of the outside, and reverse grinding is not allowed to avoid cracking the silver-copper coating 12.

[0086] The method for heat treating the parts in step 6 is: placing the parts in a vacuum furnace and heating them to 520°C~570°C, keeping them warm for 2h~4h, and controlling the vacuum degree in the vacuum furnace to below 13Pa, then filling the vacuum furnace with argon gas and turning on the circulating fan to cool the parts until the pressure in the vacuum furnace rises to (1~1.4)×10 5Pa.

[0087] The special lathe tool 2 in step 11 includes a positioning plate 20 and a plurality of clamping components uniformly arranged on the positioning plate 20 .

[0088] The positioning plate 20 is made of 45# steel with a hardness of HRC35-40. A plurality of positioning holes 200 are evenly distributed on the positioning plate 20, and threaded holes A201 are evenly distributed with the same number as the clamping components. A blind hole A202 is coaxially provided on one end surface of the positioning plate 20, and a reference blind hole 203 is provided on the other end surface, and a tool-releasing blind hole 204 is coaxially provided on the bottom surface of the reference blind hole 203.

[0089] The end face of the positioning plate 20 with the blind hole A202 is used as the reference surface A205, the parallelism of the bottom face of the reference blind hole 203 relative to the reference surface A205 is 0.01mm, and the verticality of the hole wall of the reference blind hole 203 relative to the reference surface A205 is 0.01mm. When in use, the blind hole A202 is coaxially processed on one end face of the positioning plate 20 to make the end face of the positioning plate 20 more flat and better fit with the contact surface on the machine tool fixture. Multiple positioning holes 200 are evenly processed on the positioning plate 20 to facilitate positioning and fixing the positioning holes 200 to the machine tool. The reference blind hole 203 matches the outer circle of the large end of the part. The parallelism of the bottom surface of the reference blind hole 203 relative to the reference plane A205 is 0.01mm, and the verticality of the hole wall of the reference blind hole 203 relative to the reference plane A205 is 0.01mm, ensuring the positioning and clamping accuracy of the part, making the large end surface of the part better fit with the bottom surface of the reference blind hole 203, and making the large end outer circle of the part better fit with the hole wall of the reference blind hole 203. The tool-allowing blind hole 204 is coaxially processed on the bottom surface of the reference blind hole 203 to facilitate tool-allowing when turning the inner cavity of the part.

[0090] The clamping assembly includes a pressing plate 21 and a screw 22. The pressing plate 21 is made of 45# steel with a hardness of HRC35-40. The pressing plate 21 is L-shaped, and one end face thereof is an arc surface. An elongated hole 210 is provided on the pressing plate 21. One end of the screw 22 passes through the elongated hole 210 on the pressing plate 21 and is threadedly connected with the positioning plate 20. When in use, one end face of the pressing plate 21 is an arc surface, and the arc surface is in line contact with the positioning plate 20. At the same time, the elongated hole 210 is processed on the pressing plate 21 to facilitate the movement of the pressing plate 21 during assembly, all in order to better press the step surface on the outer circle of the part and ensure the stability and reliability of the positioning and clamping of the part by the special lathe tool 2.

[0091] The method of clamping parts using the special lathe tool 2 in step 11 is: using the end face of the large outer circle end turned in step 10 as support and the outer circle of the large end as reference, insert the large end of the part into the reference blind hole 203 on the positioning plate 20, and then tighten the screws 22 in each clamping assembly evenly, so that the pressure plate 21 is pressed tightly against the step surface processed on the outer circle of the part in step 5. When the special lathe tool 2 clamps the parts, using the end face of the large outer circle end on the part as support and the outer circle of the large end as reference, the pressure plate 21 is used to press the step surface on the outer circle of the part, thereby achieving part clamping, effectively reducing the force on the parts, and the forces on the parts are even, significantly reducing the deformation of the parts caused by extrusion during the processing, improving the processing stability of the parts, and reducing the risk of part deformation exceeding the tolerance.

[0092] The positioning shaft 30 and the pressing cover 31 are made of 45# steel with a hardness of HRC35-40;

[0093] The parallelism of the two end surfaces of the supporting section 301 is 0.01 mm, and the coaxiality of the outer cylindrical surface of the positioning boss 303 relative to the outer cylindrical surface of the clamping section 300 is 0.01 mm;

[0094] A sink 310 is coaxially provided on the end surface of the pressing cover 31 close to the positioning shaft 30, and a through hole 311 is coaxially provided on the pressing cover 31. A plurality of lightening holes 312 are evenly distributed on the pressing cover 31.

[0095] The connecting member 32 is a screw A. One end of the connecting member 32 passes through the through hole 311 on the pressing cover 31 and is threadedly connected with the threaded hole B304 on the positioning shaft 30 .

[0096] The method of clamping the parts using the special milling machine tool 3 in step 12 is as follows: using the inner hole of the silver-copper coating 12 as a reference, insert the positioning section 302 on the positioning shaft 30 into the part, and ensure that the large end of the part is close to the supporting section 301, and then connect the clamping cover 31 to the positioning shaft 30 through the connecting piece 32 and tighten it. Fig.17 As shown, since the silver-copper coating 12 is relatively soft, a plurality of positioning bosses 303 are circumferentially arranged on the positioning section 302 of the positioning shaft 30, and the positioning bosses 303 cooperate with the reference positioning surface of the inner cavity of the part, and the outer cylindrical surface of the positioning bosses 303 fits with the junction of the inner cavity material body of the part and the silver-copper coating 12 to reduce the contact area between the positioning shaft 30 and the silver-copper coating 12, thereby being able to well protect the silver-copper coating 12.

[0097] When the special milling machine tool 3 clamps the parts, one end face of the part is used as the support, and the inner hole of the silver-copper coating 12 is used as the reference. The other end face of the part is pressed by the clamping cover 31, thereby achieving part clamping, effectively reducing the force on the part, and the force on the part is uniform, which significantly reduces the deformation of the part caused by extrusion during the processing, improves the processing stability of the part, and can reduce the risk of excessive deformation of the part.

[0098] After the step thirteen is completed, the thin-walled sealing ring 1 is cleaned and finally inspected according to the drawing, and then the thin-walled sealing ring 1 is wrapped with foam paper and covered with a protective net and placed in a packaging bag for packaging.

Claims

1. A thin-wall sealing ring processing technology, characterized in that: The following steps are involved: Step 1: Material preparation: prepare the part blank, which is a cylindrical part; Step 2: Rough turning of the blank: Rough turning of the two end faces, outer circle and inner hole of the parts to remove the surface oxide scale; Step 3: Ultrasonic testing: Perform ultrasonic testing on the parts to ensure that there are no bubbles or cracks in the internal material structure of the parts; Step 4: machining the outer shape and boring the hole: clamp the outer circle of the part, machine the end face, bore the inner hole, and machine the coating ring groove (11) in the inner hole to the target size; Step 5: Turning the end face and outer circle: Using the end face of the part processed in step 4 as a support, support the inner hole of the part to turn the outer circle and end face, and process its outer circle into a step shape; Step 6: Heat treatment: Heat treat the parts to remove the stress generated by the previous machining process; Step 7: Washing: Clean the parts; Step 8, spraying silver-copper coating: plasma spraying silver-copper coating (12) in the coating ring groove (11); Step 9: Remove the flash of the silver-copper coating: Grind and remove the flash of the silver-copper coating (12); Step 10: Finish turning the end face: Use soft three-jaw clamping to turn the outer circle of the part on the CNC lathe to turn the end face of the outer circle; Step 11: Finish turning the outer shape and inner cavity: Use a special CNC lathe (2) to clamp the part and align the end face of the part so that the runout is no more than 0.02 mm. Finish turn the end face of the part, bore the inner hole, and chamfer the part on a CNC lathe to turn the inner cavity of the part to the target size. Step 12: Finish turning the outer shape and milling holes: Use a special milling machine tool (3) to clamp the part, finish turning the outer circle of the part on a five-axis turning and milling machining center, drill all vertical holes (14) and non-vertical holes (13) on the outer circle of the part, mill four square bosses (10) on the outer circle of the end face of the part, and process the outer dimensions of the part to the target size; Step 13: chamfering and deburring: chamfering all holes on the parts and removing the burrs from the holes to obtain a thin-walled sealing ring (1); The special milling machine tool (3) in step twelve comprises a positioning shaft (30) and a clamping cover (31), wherein the clamping cover (31) is coaxially arranged with the positioning shaft (30) and is detachably connected to one end of the positioning shaft (30) via a connecting piece (32); The positioning shaft (30) comprises a coaxially arranged clamping section (300), a supporting section (301) and a positioning section (302); one end of the supporting section (301) is connected to one end of the clamping section (300), and the other end is connected to one end of the positioning section (302); and the diameter of the supporting section (301) is larger than the diameter of the clamping section (300) and the diameter of the positioning section (302); A plurality of positioning bosses (303) are provided on the positioning section (302) along the circumferential direction, and a threaded hole B (304) is coaxially provided on one end of the positioning section (302) away from the supporting section (301); the outer circumferential surface of the positioning boss (303) is adapted to the inner circumferential surface of the silver-copper coating (12), and the outer circumferential surface of the positioning boss (303) is in contact with the interface between the inner cavity material body of the part and the silver-copper coating (12), so as to reduce the contact area between the positioning shaft (30) and the silver-copper coating (12); The special lathe tool (2) in step 11 comprises a positioning plate (20) and a plurality of clamping components evenly arranged on the positioning plate (20); The positioning disk (20) is evenly provided with a plurality of positioning holes (200) and evenly provided with threaded holes A (201) whose number is the same as that of the clamping components; a blind hole A (202) is coaxially provided on the end surface of one end of the positioning disk (20), a reference blind hole (203) is provided on the end surface of the other end, and a tool-allowing blind hole (204) is coaxially provided on the bottom surface of the reference blind hole (203); the end surface of the positioning disk (20) provided with the blind hole A (202) is used as the reference surface A (205); The clamping assembly comprises a pressing plate (21) and a screw (22); the pressing plate (21) is L-shaped, one end surface of which is an arc surface, and an elongated hole (210) is provided on the pressing plate (21); one end of the screw (22) passes through the elongated hole (210) on the pressing plate (21) and is threadedly connected to the positioning plate (20); The method of clamping the parts by using the special lathe tool (2) in step 11 is as follows: using the end face of the large outer circle end finely turned in step 10 as a support and the outer circle of the large end as a reference, inserting the large end of the part into the reference blind hole (203) on the positioning plate (20), and then evenly tightening the screws (22) in each clamping assembly so that the pressing plate (21) is pressed tightly against the step surface machined on the outer circle of the part in step 5; The method for clamping the parts using the special milling machine tool (3) in step 12 is as follows: using the inner hole of the silver-copper coating (12) as a reference, inserting the positioning section (302) on the positioning shaft (30) into the part, and ensuring that the large end of the part is close to the supporting section (301), and then connecting the clamping cover (31) and the positioning shaft (30) through the connecting piece (32) and tightening them.

2. The thin-wall sealing ring processing process according to claim 1, characterized in that: The blank in step 1 is a ring forging after solution treatment and aging treatment, and the material is precipitation-strengthened nickel-based high-temperature alloy GH4169; After step 5 is completed, the size of the parts is inspected according to the drawings; After step 6 is completed, the parts are subjected to fluorescence inspection to ensure that there are no defects on the surface of the parts; When grinding and removing the flash of the silver-copper coating (12) in step nine, the flash is removed by grinding from the inner hole of the part to the outside.

3. The thin-wall sealing ring processing process according to claim 1, characterized in that: The method for heat treating the parts in step 6 is: placing the parts in a vacuum furnace and heating them to 520°C~570°C, keeping them warm for 2h~4h, and controlling the vacuum degree in the vacuum furnace to below 13Pa, then filling the vacuum furnace with argon gas and turning on the circulating fan to cool the parts until the pressure in the vacuum furnace rises to (1~1.4)×10 5 Pa.

4. The thin-wall sealing ring processing process according to claim 1, characterized in that: The positioning plate (20) is made of 45# steel with a hardness of HRC35-40; the parallelism of the bottom surface of the reference blind hole (203) relative to the reference plane A (205) is 0.01 mm, and the verticality of the hole wall of the reference blind hole (203) relative to the reference plane A (205) is 0.01 mm.

5. The thin-wall sealing ring processing process according to claim 1, characterized in that: The pressing plate (21) is made of 45# steel with a hardness of HRC35-40.

6. The thin-wall sealing ring processing process according to claim 1, characterized in that: The positioning shaft (30) and the pressing cover (31) are made of 45# steel with a hardness of HRC35-40; The parallelism of the two end surfaces of the supporting section (301) is 0.01 mm, and the coaxiality of the outer cylindrical surface of the positioning boss (303) relative to the outer cylindrical surface of the clamping section (300) is 0.01 mm; A sink (310) is coaxially provided on an end surface of the pressing cover (31) close to the positioning shaft (30), and a through hole (311) is coaxially provided on the pressing cover (31). The pressing cover (31) is also evenly provided with a plurality of lightening holes (312); The connecting member (32) is a screw A. One end of the connecting member (32) passes through the through hole (311) on the pressing cover (31) and is then threadedly connected to the threaded hole B (304) on the positioning shaft (30).

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