A kind of non-hole ear support plate nut for high temperature environment and its processing technology

Abstract

This invention relates to the field of aerospace fastener technology, and particularly to a holeless lug nut for high-temperature environments and its processing technology. The nut, from left to right, comprises a riveting section, a support plate section, a main body section, a transition section, and a closing section. An internal thread is provided in the inner hole formed by the support plate section and the main body section. The inner wall of the closing section is an open-tailed inner conical surface, which is used to contact and seal with the conical surface at the tail of the screw. Compared to existing dustproof nuts with a fully enclosed tail, this invention uses an open-tailed inner conical surface to contact and seal with the conical surface at the tail of the screw. Therefore, the assembled threaded pair does not have a closed cavity, and a high-pressure gas chamber will not form under high-temperature conditions, effectively avoiding the risk of high-temperature gas suddenly escaping and damaging other parts. The holeless lug nut prepared using the processing technology provided by this invention has excellent high-temperature performance and is suitable for fastening parts in high-temperature environments.

Description

Technical Field

[0001] The invention relates to the technical field of aerospace fasteners, and in particular to a hole-free ear support plate nut for high-temperature environments and a processing technology thereof. Background Art

[0002] In the field of aerospace fasteners, fasteners used to connect important components in high-temperature environments must have good mechanical properties and anti-loosening properties in high-temperature environments, as well as the characteristics of easy installation, disassembly, and maintenance.

[0003] At the high-temperature end of aircraft engines, in order to reduce the weight of parts as much as possible, part design and material selection follow the principles of high strength, high temperature resistance, thin wall and light weight. Mechanical connections between parts are inevitable, but due to the narrow space, conventional bolt and nut tightening methods cannot be achieved; when tapping threads on parts, due to the thin parts (0.5~3mm), the short thread length cannot be tightened or the axial force load cannot meet the technical requirements, the threaded connection also needs to be sealed, and the medium in the internal space cannot leak out through the threads.

[0004] like Figure 1 The figure shows a commonly used fastener structure at present, in which a dustproof nut 101 is embedded in a part body 100, and a screw passes through a connecting piece 102 and is screwed into the internal thread of the dustproof nut 101, thereby fastening the connecting piece 102 to the part body 100. In this fastener structure, the dustproof nut 101 is located in the inner cavity of the part body 100, and the annular boss on the outer peripheral surface abuts against the inner wall of the part body 100, thereby playing a sealing role and preventing the medium 103 in the inner cavity of the part body 100 from leaking. However, the use of Figure 1 The fastener structure in the invention has the following problems:

[0005] (1) The tail of the dustproof nut 101 is a fully enclosed structure. When the dustproof nut 101 is assembled with the screw to form a threaded pair, a closed cavity 104 is formed inside the dustproof nut 101. Since the threaded pair is assembled under standard conditions with a relative humidity of 65%, the air in the closed cavity 104 contains a certain amount of water vapor. As the aircraft engine runs, the temperature continues to rise, and the water vapor in the closed cavity 104 forms a high-pressure air chamber, which poses a risk of high-temperature gas suddenly rushing out and endangering other parts.

[0006] (2) The nut structure with a fully enclosed nut at the tail has relatively large dimensions, which is not conducive to reducing the weight of the parts. Summary of the invention

[0007] The main purpose of the present invention is to provide a hole-free ear support plate nut for high temperature environment and its processing technology, aiming to solve the above technical problems.

[0008] To achieve the above-mentioned purpose, on the one hand, the present invention proposes a hole-free ear support plate nut for high-temperature environment, which includes, from left to right, a riveting section, a support plate section, a main body section, a transition section and a closing section; an internal thread is arranged in the inner hole formed by the support plate section and the main body section; the inner wall of the closing section is an open-end inner conical surface, and the inner conical surface of the closing section is used for contact sealing with the conical surface of the tail of the screw.

[0009] Preferably, knurling is provided on the outer peripheral surface of the riveting section, and chamfers are provided on the edges of the end surface of the riveting section.

[0010] Preferably, an annular empty groove is provided between the riveted section and the support plate section; the inner diameter of the transition section is larger than the diameter of the internal thread, and a transition cone surface is used to transition between the inner circumference of the transition section and the internal thread; an annular clearance groove is formed at the inner circumference of the transition section; the diameter of the inner hole of the riveted section is larger than the diameter of the internal thread; and a guide cone surface is used to transition between the inner hole of the riveted section and the internal thread.

[0011] Preferably, the taper of the inner conical surface of the closing section is 60°; the nominal value of the diameter of the inner conical surface of the closing section is φ4.5mm; the bolt length error of the screw is not greater than 0.3mm; the material of the hole-free ear support plate nut is GH4033.

[0012] Preferably, a pair of tangent planes are provided on the outer peripheral surface of the support plate segment, and the two tangent planes are symmetrically arranged at 180°; the perpendicularity between the end surface of the support plate segment close to the riveting segment and the center line of the internal thread is not greater than 0.03.

[0013] On the other hand, the present invention also provides a processing technology for the above-mentioned hole-free ear support plate nut for high temperature environment, which is used to manufacture the above-mentioned hole-free ear support plate nut for high temperature environment, comprising the following steps:

[0014] Step S1, material preparation: using cold drawn bars of high temperature nickel-based alloy GH4033 as raw materials;

[0015] Step S2, solution heat treatment;

[0016] Step S3, CNC lathe: turning the outer circles of the riveted section, the support plate section and the main section, turning the annular hollow grooves and chamfers; knurling the outer peripheral surface of the riveted section; drilling and boring; boring the inner hole of the closing section according to the straight hole; cutting; using one-time clamping processing to ensure the verticality of the end face of the support plate section and the center;

[0017] Step S4: after deburring, the parts obtained in step S3 are subjected to CNC lathing: the outer circles of the transition section and the closing section are turned, and the closing section is turned according to the cylindrical surface;

[0018] Step S5, CNC milling: milling a cutting plane on the outer peripheral surface of the support plate segment, and chamfering the edges of the cutting plane;

[0019] Step S6, deburring and tapping: tapping the inner hole formed by the support plate section and the main body section to form an internal thread;

[0020] Step S7, mid-inspection: inspect the dimensions of the closing section before closing;

[0021] Step S8, closing the mouth: using a spinning device on a CNC lathe to close the mouth, so that the inner and outer peripheral surfaces of the closing section form a tapered surface;

[0022] Step S9, aging heat treatment;

[0023] Step S10: sandblasting, grinding, cleaning, general inspection, packaging and storage.

[0024] Preferably, in step S2, the method of solution heat treatment is: placing the raw materials in a vacuum heat treatment furnace, the furnace temperature should be lower than 300°C, heating to 850~860°C, preheating for 30~40min, heating to 1090~1100°C, keeping warm for 480~500min, and the vacuum degree should be controlled below 13.3Pa; vacuum oil cooling in the furnace, and argon gas cooling; in step S9, the method of aging heat treatment is: placing the nut in a vacuum heat treatment furnace after closing, the furnace temperature should be lower than 100°C, heating to 700°C±10°C, keeping warm for 960~970min, and the vacuum degree should be controlled below 13.3Pa; argon gas is filled in the furnace for protection cooling.

[0025] Preferably, in step S8, the spinning device used for closing includes a positioning shaft, an inner cone mold head, a supporting seat, a connecting pin shaft and a clamping shaft; the positioning shaft is used to be installed on a CNC lathe and clamp and position the holeless ear support plate nut; the right end of the clamping shaft is used to be clamped on the tool holder of the CNC lathe; the internal threaded hole at the right end of the supporting seat is screwed onto the external thread at the left end of the clamping shaft; the connecting pin shaft is inserted into the center hole of the supporting seat, and the left end of the connecting pin shaft extends from the center hole of the supporting seat and is inserted into the inner hole of the inner cone mold head to form a rotatable fit; a ball is arranged in the annular groove on the left end face of the supporting seat, and the right end face of the inner cone mold head abuts against the ball; a molding cone surface is arranged at the left end of the inner hole of the inner cone mold head.

[0026] Preferably, the left section of the positioning shaft is configured as a clamping portion for clamping on a CNC lathe, and the right section of the positioning shaft is configured as a screw portion for threaded cooperation with the internal thread of a hole-free ear support plate nut; an annular limit platform is provided between the clamping portion and the screw portion; a supporting portion is integrally formed at the right end of the screw portion, the supporting portion extends into the inner hole of the closing section, and when closing is performed in step S8, the edge of the inner conical surface of the closing section abuts against the outer peripheral surface of the supporting portion.

[0027] Preferably, the connecting pin is in the shape of a stepped shaft, with the outer diameter gradually increasing from left to right, and sequentially including a rotational fitting section, an insertion section and an axial limit head; the insertion section is inserted in the center hole of the left half of the supporting seat, and a tightening screw is screwed on the supporting seat, and the inner end of the tightening screw is tightened on the outer peripheral surface of the insertion section; an accommodating countersunk hole is provided on the left end surface of the clamping shaft; the axial limit head is provided in the accommodating countersunk hole; a V-shaped ring groove is provided on the outer peripheral surface of the rotational fitting section; the rotational fitting section is inserted in the inner hole of the inner cone mold head to form a rotatable fit; an axial limit top screw is screwed on the inner cone mold head, and the inner tip of the axial limit top screw is stuck in the V-shaped ring groove.

[0028] Due to the adoption of the above technical solution, the beneficial effects of the present invention are as follows:

[0029] (1) When the hole-less ear support plate nut provided by the present invention is used to fasten the part body and the connecting piece, it is only necessary to rivet the riveting section of the hole-less ear support plate nut on the part body, and the screw passes through the connecting piece and is screwed into the internal thread on the inner hole formed by the support plate section and the main body section. When the screw is tightened, the support plate section and the part body are in close contact to form a seal, and at the same time, the conical surface of the screw tail and the inner conical surface of the closing section are closely fitted to form a seal. Therefore, the screw and the hole-less ear support plate nut cooperate with each other to play a sealing and fastening role.

[0030] (2) Compared with the dustproof nut with a fully enclosed tail in the prior art, the present invention adopts an open tail inner cone surface that contacts and seals with the tail cone surface of the screw. There is no closed cavity in the assembled thread pair, so no high-pressure gas chamber is formed under high temperature conditions, effectively avoiding the risk of high-temperature gas suddenly rushing out and endangering other parts.

[0031] (3) In the present invention, since the ear-less support plate nut adopts an open tail structure, the outer dimensions of the nut can be smaller than those of the dustproof nut in the prior art, which is beneficial to reducing the weight of the parts.

[0032] (4) The ear-less support plate nut prepared by the processing technology provided by the present invention has good high-temperature performance and is suitable for fastening parts in a high-temperature environment.

[0033] (5) In the present invention, when the spinning device is used for closing, the inner cone die head can rotate to reduce the friction between the inner cone die head and the parts and improve the forming effect of the closing section. BRIEF DESCRIPTION OF THE DRAWINGS

[0034] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on the structures shown in these drawings without paying creative work.

[0035] Figure 1 It is a schematic diagram of the prior art when a dustproof nut is used for tightening;

[0036] Figure 2 This is a schematic diagram of the structure of the ear-free support plate nut provided by the present invention;

[0037] Figure 3 A three-dimensional diagram of a lug-free support plate nut provided by the present invention;

[0038] Figure 4 This is a schematic diagram of a connection using the hole-free ear support plate nut provided by the present invention;

[0039] Figure 5 It is a schematic diagram of the structure of a screw with a conical surface at the tail portion used in the present invention;

[0040] Figure 6 This is an analysis diagram of the maximum error in bolt length and the diameter change of the tail in the present invention;

[0041] Figure 7 It is a schematic diagram of a non-hole ear support plate nut when the end is not closed in the present invention;

[0042] Figure 8 It is a schematic diagram of the present invention when a spinning device is used on a CNC lathe to close the mouth;

[0043] Fig. 9 for Figure 8 The enlarged view of the M in the middle;

[0044] Fig.10 It is a structural schematic diagram of a positioning shaft in a spinning device;

[0045] Fig.11 It is a schematic diagram of the structure of the inner cone die head in the spinning device;

[0046] Fig.12 It is a structural schematic diagram of a support seat in a spinning device;

[0047] Fig.13 It is a schematic diagram of the structure of the connecting pin in the spinning device;

[0048] Fig.14 It is a schematic diagram of the structure of the clamping shaft in the spinning device.

[0049] Description of the accompanying symbols: 1, riveting section; 1a, knurling; 1b, chamfer; 1c, guiding cone; 2, supporting plate section; 2a, cutting plane; 3, main section; 4, transition section; 4a, transition cone; 5, closing section; 6, internal thread; 7, annular empty slot; 8, annular clearance groove; 9, positioning shaft; 9a, clamping part; 9b, screw part; 9c, annular limit platform; 9d, supporting part; 10, inner cone die head; 10a, forming cone; 11, supporting Bearing; 12, connecting pin; 12a, rotating matching section; 12b, plug-in section; 12c, axial limit head; 12d, V-shaped ring groove; 13, clamping shaft; 13a, accommodating countersunk hole; 14, ball bearing; 15, axial limit top screw; 16, tightening screw; 100, part body; 101, dustproof nut; 102, connecting piece; 103, medium; 104, closed cavity; 105, screw; 17, CNC lathe spindle; 18, small pallet. DETAILED DESCRIPTION

[0050] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0051] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative position relationship, movement status, etc. between the components under a certain specific posture (as shown in the accompanying drawings). If the specific posture changes, the directional indication will also change accordingly.

[0052] Combine 1 to Figure 5 As shown, on the one hand, this embodiment provides a hole-free ear support plate nut for high-temperature environment, which includes, from left to right, a riveting section 1, a support plate section 2, a main body section 3, a transition section 4 and a closing section 5; an internal thread 6 is arranged in the inner hole formed by the support plate section 2 and the main body section 3; the inner wall of the closing section 5 is an open-end inner conical surface, and the inner conical surface of the closing section 5 is used for contact sealing with the conical surface at the end of the screw 105.

[0053] Combination Figure 4As shown, when fastening the part body 100 and the connector 102, it is only necessary to rivet the riveting section 1 of the hole-free ear support plate nut on the part body 100, and the screw 105 passes through the connector 102 and is screwed into the internal thread 6 on the inner hole formed by the support plate section 2 and the main section 3. When the screw 105 is tightened, the support plate section 2 and the part body 100 are in close contact to form a seal, and at the same time, the conical surface of the tail of the screw 105 is closely fitted with the inner conical surface of the closing section 5 to form a seal. Therefore, the screw 105 and the hole-free ear support plate nut cooperate with each other to play a sealing and fastening role. The medium 103 in the inner cavity of the part body 100 cannot leak out of the cavity through the thread gap, or impurities in the cavity cannot enter the thread gap, which affects the service life of the thread pair. Compared with the dust-proof nut 101 with a fully enclosed tail in the prior art, since the present invention adopts an open inner cone at the tail to contact and seal with the tail cone of the screw 105, there is no closed cavity in the assembled thread pair, so no high-pressure gas chamber will be formed under high temperature conditions, effectively avoiding the risk of high-temperature gas suddenly rushing out and endangering other parts.

[0054] Combination Figure 2 , Figure 3 As shown, knurling 1a is provided on the outer peripheral surface of the riveted section 1, and chamfering 1b is provided on the edge of the end surface of the riveted section 1. In this embodiment, the knurling 1a is a straight knurling. Due to the provision of the knurling 1a, when the holeless ear support plate nut is riveted to the part body 100, when the screw 105 is tightened or removed, the rotation of the nut is effectively prevented.

[0055] Combination Figure 2 As shown, an annular hollow groove 7 is provided between the riveted section 1 and the support plate section 2, so as to prevent the root of the connection between the support plate section 2 and the riveted section 1 from interfering with the component body 100 and affecting the contact sealing effect between the support plate section 2 and the component body 100.

[0056] Combination Figure 2 and Figure 4 As shown, the inner diameter of the transition section 4 is larger than the diameter of the internal thread 6, and a transition conical surface 4a is used to transition between the inner circumference of the transition section 4 and the internal thread 6; an annular clearance groove 8 is formed at the inner circumference of the transition section 4. By providing the annular clearance groove 8, when assembling the screw 105, interference with the tail of the screw 105 can be avoided, so as to ensure that the conical surface of the tail of the screw 105 can be closely fitted with the inner conical surface of the closing section 5.

[0057] Combination Figure 2 and Figure 4 As shown, the diameter of the inner hole of the riveting section 1 is larger than the diameter of the internal thread 6. The inner hole of the riveting section 1 and the internal thread 6 are transitioned through a guide cone surface 1c. The guide cone surface 1c is provided to guide the screw 105 for easy assembly.

[0058] In this embodiment, the taper of the inner cone of the closing section 5 is 60°; the nominal diameter of the inner cone of the closing section 5 is φ4.5mm; the error of the bolt length L3 of the screw 105 is not greater than 0.3mm; the material of the hole-free ear support plate nut is GH4033. Figure 5 , Figure 6 As shown in the figure, assuming that the maximum error of bolt length is A=0.3, the diameter change of the tail is B=0.3*tan(30°)=0.1732mm, and the circumference change is 2*0.3*tan(30)*π=1.088mm. The minimum elongation of GH4033 material is 13%, and the diameter of the inner cone of the closing section 5 is φ4.5mm, and its allowable elongation is C=4.5*π*0.13=1.838mm. Therefore, the bolt length error causes the circumference change of 1.088mm here to be less than the allowable extension length of the material of 1.838mm.

[0059] It can be deduced from the above calculation conclusions that the bolt length error of the control screw 105 is within a certain range, and the inner conical surface of the closing section 5 adopts a 60° cone and will not break due to the bolt length.

[0060] Combination Figure 3 As shown, a pair of cutting planes 2a are provided on the outer peripheral surface of the support plate segment 2, and the two cutting planes 2a are symmetrically arranged at 180°; by providing the cutting planes 2a, the riveting section of the non-hole ear support plate nut is riveted to the part body by using an installation tool, and the installation tool can be clamped on the cutting planes 2a to prevent relative rotation. The verticality between the end surface of the support plate segment 2 close to the riveting section 1 and the center line of the internal thread 6 is not greater than 0.03, ensuring that the support plate segment 2 can be vertically abutted against the part body 100.

[0061] On the other hand, the present embodiment also provides a processing technology for the above-mentioned hole-free ear support plate nut for high temperature environment, comprising the following steps:

[0062] Step S1, material preparation: using cold drawn bars of high temperature nickel-based alloy GH4033 as raw materials.

[0063] Step S2: solution heat treatment.

[0064] Step S3, CNC lathe: turning the outer circles of the riveted section 1, the support plate section 2 and the main section 3, turning the annular hollow groove 7 and the chamfer 1b; processing the knurling 1a on the outer peripheral surface of the riveted section 1; drilling and boring, specifically, firstly, a through hole is processed in the center of the workpiece by drilling, and then the inner hole of the riveted section 1, the guide cone surface 1c, the bottom hole of the internal thread 6, the transition cone surface 4a, the annular clearance groove 8 and the inner hole of the closing section 5 are processed in the through hole by boring, and the inner hole of the closing section 5 is bored according to the straight hole and a margin is left; cutting; one-time clamping is used to ensure that the verticality between the end face of the support plate section 2 and the center is not greater than 0.03.

[0065] Step S4: After deburring, the parts obtained in step S3 are CNC machined: the outer circles of the transition section 4 and the closing section 5 are turned, and the closing section 5 is turned according to the cylindrical surface. Figure 7 shown.

[0066] Step S5, CNC milling: milling the cutting plane 2a on the outer peripheral surface of the supporting plate segment 2, and chamfering the edges of the cutting plane 2a.

[0067] Step S6, deburring and tapping: tapping MR6 is performed on the inner hole formed by the support plate section 2 and the main body section 3 to form an internal thread 6.

[0068] Step S7, intermediate inspection: inspect the dimensions of the closing section 5 before closing.

[0069] Step S8, closing the mouth: using a spinning device on a CNC lathe to close the mouth, so that the inner and outer peripheral surfaces of the closing section 5 both form conical surfaces.

[0070] Step S9: aging heat treatment.

[0071] Step S10, sandblasting, threading, cleaning, general inspection, packaging and storage. The purpose of sandblasting is to remove the oxide layer. Threading is to use a thread plug gauge to check the thread condition after aging heat treatment.

[0072] In step S2, the method of solution heat treatment is: placing the raw materials in a vacuum heat treatment furnace, the furnace temperature should be lower than 300°C, heating to 850-860°C, preheating for 30-40 minutes, heating to 1090-1100°C, keeping warm for 480-500 minutes, and the vacuum degree should be controlled below 13.3Pa; vacuum oil cooling in the furnace, and argon gas cooling; in step S9, the method of aging heat treatment is: placing the nut in a vacuum heat treatment furnace after closing, the furnace temperature should be lower than 100°C, heating to 700°C±10°C, keeping warm for 960-970 minutes, and the vacuum degree should be controlled below 13.3Pa; argon gas protection cooling is filled in the furnace. By performing solution + aging heat treatment, the hardness of the prepared hole-free ear support plate nut reaches HB285-341.

[0073] Combination Figures 7 to 14 As shown, in step S8, the spinning device used for closing includes a positioning shaft 9, an inner cone die head 10, a support seat 11, a connecting pin shaft 12 and a clamping shaft 13; the positioning shaft 9 is used to be installed on a CNC lathe and clamp and position the holeless ear support plate nut; the right end of the clamping shaft 13 is used to be clamped on the tool holder of the CNC lathe; the internal threaded hole at the right end of the support seat 11 is screwed on the external thread at the left end of the clamping shaft 13; the connecting pin shaft 12 is inserted in the center hole of the support seat 11, and the left end of the connecting pin shaft 12 extends from the center hole of the support seat 11 and is inserted into the inner hole of the inner cone die head 10 to form a rotatable fit; a ball 14 is arranged in the annular groove on the left end face of the support seat 11, and the right end face of the inner cone die head 10 abuts against the ball 14; a forming cone surface 10a is arranged at the left end of the inner hole of the inner cone die head 10.

[0074] Furthermore, the left section of the positioning shaft 9 is set as a clamping portion 9a for clamping on a CNC lathe, and the right section of the positioning shaft 9 is set as a screw portion 9b for threaded cooperation with the internal thread 6 of the hole-free ear support plate nut; an annular limit platform 9c is provided between the clamping portion 9a and the screw portion 9b, and the perpendicularity between the right end face of the annular limit platform 9c and the axis of the screw portion 9b is not greater than φ0.02; a supporting portion 9d is integrally formed at the right end of the screw portion 9b, and the supporting portion 9d extends into the inner hole of the closing section 5, and when the closing is performed in step S8, the edge of the inner conical surface of the closing section 5 abuts against the outer peripheral surface of the supporting portion 9d.

[0075] Furthermore, the connecting pin shaft 12 is in the shape of a stepped shaft, with the outer diameter gradually increasing from left to right, and sequentially comprises a rotational fitting section 12a, a plug section 12b and an axial stopper 12c; the plug section 12b has a diameter of φ6h7 and is inserted into the center hole φ6H7 of the left half of the support seat 11, and a tightening screw 16 is screwed on the support seat 11, and the inner end of the tightening screw 16 is tightened on the outer peripheral surface of the plug section 12b; on the clamping shaft 13 The left end face is provided with an accommodating countersunk hole 13a; the axial limit head 12c is arranged in the accommodating countersunk hole 13a; a V-shaped ring groove 12d is arranged on the outer peripheral surface of the rotational fitting section 12a; the outer diameter of the rotational fitting section 12a is φ5h7, and it is inserted in the inner hole φ5H7 of the inner cone die head 10 to form a rotatable fit; an axial limit top screw 15 is screwed on the inner cone die head 10, and the inner tip of the axial limit top screw 15 is stuck on the V-shaped ring groove 12d.

[0076] In this embodiment, the nominal thickness of the compressed closing section 5 on the hole-free ear support plate nut is 0.55mm, and the length L1 is 1.59mm. The compression and closing are performed by rotational extrusion. The screw portion 9b of the positioning shaft 9 is used to fix the part blank. The positioning shaft 9 is installed on the soft claws of the CNC lathe spindle 17 and clamped. The right end of the clamping shaft 13 is installed on the tool holder of the small support plate 18 of the CNC lathe. The spindle rotates at a minimum speed of 12.5 / min, and the tool holder slowly moves toward the spindle direction. The feed rate is 0.5~0.6mm / min, and the total movement is about 1.5mm. The inner cone die head 10 can rotate during extrusion to reduce the friction between the inner cone die head 10 and the part, extrude the part into shape, and form a tapered closing section 5.

[0077] In summary, the functions of the main components of the spinning device are as follows:

[0078] Positioning shaft 9: The clamping part 9a on the positioning shaft 9 is used to be clamped on the CNC lathe, and the screw part 9b is used to threadably cooperate with the internal thread 6 of the non-hole ear support plate nut. The annular stopper 9c is used to abut against the left end face of the non-hole ear support plate nut. When the part is squeezed and closed, the axial load acts on the annular stopper 9c to avoid the extrusion of the thread gap, resulting in dimensional changes or out-of-tolerance; the shaft diameter of the support part 9d is the inner diameter of the part after closing, which controls the closing limit size.

[0079] Inner cone die head 10: bears external force extrusion, rotation, compression parts closing and forming, inner cone die head 10 rotates around connecting pin 12, axial force but cannot axially move; selects wear-resistant and high hardness material T8A, and performs quenching heat treatment.

[0080] Support seat 11: A ball 14 is arranged in the annular groove at the left end of the support seat 11, and the ball 14 rolls freely in the groove. The inner hole at the right end of the support seat 11 is threaded and connected to the clamping shaft 13 to play a supporting and connecting role.

[0081] The connecting pin 12 provides a rotation center and support for the inner cone die head 10 .

[0082] The left end of the clamping shaft 13 is threadedly connected to the supporting seat 11, and the right end of the clamping shaft 13 is used to be clamped on the tool holder of the CNC lathe.

[0083] The above description is only a preferred embodiment of the present invention, and does not limit the patent scope of the present invention. All equivalent structural changes made by using the contents of the present invention specification and drawings under the inventive concept of the present invention, or directly / indirectly applied in other related technical fields are included in the patent protection scope of the present invention.

Claims

1. A processing technology for a non-hole ear support plate nut for high temperature environment, used to make a non-hole ear support plate nut for high temperature environment, characterized in that: The ear-less support plate nut for high temperature environment comprises, from left to right, a riveting section (1), a support plate section (2), a main body section (3), a transition section (4) and a closing section (5); An internal thread (6) is provided in the inner hole formed by the support plate section (2) and the main body section (3); The inner wall of the closing section (5) is an open-end inner conical surface, and the inner conical surface of the closing section (5) is used for contact sealing with the conical surface of the end of the screw (105); The outer peripheral surface of the riveted section (1) is provided with knurling (1a), and the edge of the end surface of the riveted section (1) is provided with a chamfer (1b); An annular hollow groove (7) is provided between the riveting section (1) and the supporting plate section (2); the inner diameter of the transition section (4) is larger than the diameter of the internal thread (6); a transition cone (4a) is used to transition between the inner circumference of the transition section (4) and the internal thread (6); an annular clearance groove (8) is formed at the inner circumference of the transition section (4); the diameter of the inner hole of the riveting section (1) is larger than the diameter of the internal thread (6); and a guide cone (1c) is used to transition between the inner hole of the riveting section (1) and the internal thread (6); The taper of the inner conical surface of the closing section (5) is 60°; the nominal diameter of the inner conical surface of the closing section (5) is φ4.5 mm; the bolt length error of the screw (105) is not greater than 0.3 mm; the material of the non-hole ear support plate nut is GH4033; A pair of tangent planes (2a) are provided on the outer peripheral surface of the support plate section (2), and the two tangent planes (2a) are symmetrically arranged at 180 degrees; the perpendicularity between the end surface of the support plate section (2) close to the riveting section (1) and the center line of the internal thread (6) is not greater than 0.03; The processing technology includes the following steps: Step S1, material preparation: using cold drawn bars of high temperature nickel-based alloy GH4033 as raw materials; Step S2, solution heat treatment; Step S3, CNC lathe: turning the outer circles of the riveting section (1), the support plate section (2) and the main section (3), turning the annular hollow slot (7) and the chamfer (1b); processing the knurling (1a) on the outer peripheral surface of the riveting section (1); drilling and boring; boring the inner hole of the closing section (5) as a straight hole; cutting; using one-time clamping processing to ensure the verticality between the end face and the center of the support plate section (2); Step S4: after deburring, the part obtained in step S3 is subjected to CNC lathing: the outer circles of the transition section (4) and the closing section (5) are turned, and the closing section (5) is turned according to the cylindrical surface; Step S5, CNC milling: milling a cutting plane (2a) on the outer peripheral surface of the support plate segment (2), and chamfering the edges of the cutting plane (2a); Step S6, deburring and tapping: tapping the inner hole formed by the support plate section (2) and the main body section (3) to form an internal thread (6); Step S7, intermediate inspection: inspecting the dimensions of the closing section (5) before closing; Step S8, closing the mouth: using a spinning device on a CNC lathe to close the mouth, so that the inner and outer peripheral surfaces of the closing section (5) both form conical surfaces; Step S9, aging heat treatment; Step S10, sandblasting, tooth recovery, cleaning, general inspection, packaging and storage; In step S8, the spinning device used for closing the mouth comprises a positioning shaft (9), an inner cone die head (10), a support seat (11), a connecting pin shaft (12) and a clamping shaft (13); the positioning shaft (9) is used to be installed on a CNC lathe and to clamp and position the hole-free ear support plate nut; the right end of the clamping shaft (13) is used to be clamped on the tool holder of the CNC lathe; the internal threaded hole at the right end of the support seat (11) is screwed into the external threaded hole at the left end of the clamping shaft (13). The connecting pin (12) is inserted into the center hole of the supporting seat (11), and the left end of the connecting pin (12) extends out of the center hole of the supporting seat (11) and is inserted into the inner hole of the inner cone die head (10) to form a rotatable fit; a ball (14) is arranged in the annular groove on the left end surface of the supporting seat (11), and the right end surface of the inner cone die head (10) abuts against the ball (14); and a forming cone surface (10a) is arranged at the left end of the inner hole of the inner cone die head (10); The left section of the positioning shaft (9) is provided as a clamping portion (9a) for clamping on a numerically controlled lathe, and the right section of the positioning shaft (9) is provided as a screw portion (9b) for threadedly engaging with the internal thread (6) of the hole-free ear support plate nut; an annular limit platform (9c) is provided between the clamping portion (9a) and the screw portion (9b); a supporting portion (9d) is integrally formed at the right end of the screw portion (9b), the supporting portion (9d) extending into the inner hole of the closing section (5), and when the closing is performed in step S8, the edge of the inner conical surface of the closing section (5) abuts against the outer peripheral surface of the supporting portion (9d).

2. The processing technology of the non-hole ear support plate nut for high temperature environment as claimed in claim 1, characterized in that: In step S2, the method of solution heat treatment is: placing the raw materials in a vacuum heat treatment furnace, the furnace temperature should be lower than 300°C, heating to 850-860°C, preheating for 30-40 minutes, heating to 1090-1100°C, keeping warm for 480-500 minutes, and the vacuum degree should be controlled below 13.3 Pa; vacuum oil cooling in the furnace, and filling with argon gas for cooling; In step S9, the aging heat treatment method is: after closing, the nut is placed in a vacuum heat treatment furnace, the furnace temperature should be lower than 100°C, heated to 700°C±10°C, kept warm for 960-970 minutes, and the vacuum degree should be controlled below 13.3Pa; argon gas is filled into the furnace for protection and cooling.

3. The processing technology of the non-hole ear support plate nut for high temperature environment as claimed in claim 1, characterized in that: The connecting pin shaft (12) is in the shape of a stepped shaft, with an outer diameter gradually increasing from left to right, and comprises a rotational matching section (12a), an insertion section (12b) and an axial stopper (12c) in sequence; the insertion section (12b) is inserted into the center hole of the left half of the support seat (11), and a tightening screw (16) is screwed onto the support seat (11), and the inner end of the tightening screw (16) is tightened against the outer peripheral surface of the insertion section (12b); at the left end of the clamping shaft (13), The surface is provided with an accommodating countersunk hole (13a); the axial limit head (12c) is arranged in the accommodating countersunk hole (13a); a V-shaped annular groove (12d) is provided on the outer peripheral surface of the rotating fitting section (12a); the rotating fitting section (12a) is inserted into the inner hole of the inner cone die head (10) to form a rotatable fit; an axial limit top screw (15) is screwed on the inner cone die head (10), and the inner tip of the axial limit top screw (15) is stuck in the V-shaped annular groove (12d).

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