A kind of 42CrMo well completion tool assembly nitriding treatment equipment

Abstract

The application discloses a kind of 42CrMo well completion tool assembly nitriding treatment equipment, it is related to nitriding treatment equipment technical field, including furnace body, further include: support, it is fixedly connected to the furnace body inner bottom;Placement table, it is fixedly connected to the support upper end, for placing well completion tool assembly, it is made of high-purity isostatic pressing graphite material;Transmission shaft, it is rotatably connected to the furnace body inner top, its shape is several characters type;Several upper spiral vanes, it is fixedly connected to the transmission shaft side wall.The application in this paper is set up by upper spiral vane and lower spiral vane reverse spiral and the injection of pulse type ammonia gas, forms the violent up and down convection and radial shear force in furnace body, cooperates unique several characters type transmission shaft, utilizes conda effect and dean vortex in fluid mechanics, forcibly breaks the stationary gas film and concentration boundary layer of workpiece surface, also kneads active nitrogen atom into deep hole and thread dead angle, improves nitriding efficiency and uniformity, eliminates mottle.

Description

Technical Field

[0001] This invention relates to the field of nitriding equipment technology, and more particularly to a nitriding equipment for 42CrMo well completion tool components. Background Technology

[0002] 42CrMo steel is widely used in the manufacture of well completion tool components in oil and gas extraction due to its high strength, high toughness and excellent fatigue resistance. These components are usually complex in structure, thick in wall and have deep holes, threads and keyways. They need to withstand extremely high tensile, extrusion and impact loads under service conditions. Therefore, the requirements for its surface hardness, wear resistance and core toughness are extremely high. Ion nitriding is currently the preferred process to improve its surface properties.

[0003] In the existing nitriding process of 42CrMo well completion tool components, the heat source is usually located at the top or around the perimeter of the large furnace chamber, resulting in a severe temperature difference between the top and bottom. At the same time, ammonia gas, under static or simple laminar flow conditions, easily forms dead zones and gas films in the deep holes and thread roots of the workpiece, hindering the adsorption and diffusion of active nitrogen atoms, causing uneven nitriding layers, spots, or soft spots. In addition, the yield strength of the well completion tool component decreases significantly under the high temperature of nitriding, and it is very easy to become unstable or sag in the middle under its own weight. Traditional equipment relies only on the rigid support at the bottom, resulting in huge compressive stress at the bottom of the component and tensile stress at the top, which can easily cause micro-cracks or macro-warping, leading to the scrapping of the workpiece. Summary of the Invention

[0004] To address the problems mentioned in the background section, the present invention adopts the following technical solution: A device for nitriding 42CrMo well completion tool components, comprising a furnace body, and further comprising: A support frame is fixedly connected to the bottom of the furnace body; The placement platform, which is fixedly connected to the upper end of the bracket, is used to place the well completion tool assembly and is made of high-purity isostatic graphite material. The drive shaft is rotatably connected to the top of the furnace body and is shaped like a "Z". Several upper spiral fan blades are fixedly connected to the side wall of the drive shaft; Several lower spiral fan blades are fixedly connected to the side wall of the drive shaft, and their spiral direction is opposite to that of the upper spiral fan blades, and they are located below the upper spiral fan blades; The motor is fixedly connected to the upper end of the furnace body, and its output end passes through the upper end of the furnace body and is fixedly connected to the drive shaft. An air jet assembly is disposed on the inner wall of the furnace body; The jet assembly includes: Several fixing plates are fixedly connected to the inner wall of the furnace body; A rotating shaft is rotatably connected to the side walls of the two fixed plates that are close to each other; The mounting block is fixedly connected to the side wall of the rotating shaft; The nozzle is fixedly connected to the side wall of the mounting block and is positioned at a 70-degree angle to the bottom of the furnace body and the horizontal direction. An air inlet pipe, one end of which is connected to the nozzle and the other end of which is fixedly connected to an external air pump; A pulse solenoid valve is installed on the inner wall of the intake pipe.

[0005] Preferably, a resistance band heater is fixedly connected to the inner wall of the furnace body, and the resistance band heater is located above the upper spiral fan blade.

[0006] Preferably, a positioning component is installed on the placement platform. The positioning component includes multiple outer positioning frames fixedly connected to the upper end of the placement platform. The multiple outer positioning frames are arranged in a circular array around the center of the placement platform. An installation groove is opened on the side wall of the outer positioning frame. An outer positioning rod is slidably connected to the inner wall of the installation groove. A spring is fixedly connected between the inner wall of the installation groove and the outer positioning rod.

[0007] Preferably, the positioning component further includes a positioning column fixedly connected to the upper end of the placement platform. The side wall of the positioning column is provided with a plurality of mounting grooves, and an inner positioning rod is slidably connected to the inner wall of each mounting groove. A spring is fixedly connected between the inner wall of the mounting groove and the inner positioning rod.

[0008] Preferably, an FBG strain sensor is embedded in the side wall of the outer positioning frame, and the FBG strain sensor, the pulse solenoid valve, and the motor are electrically connected through a PLC control circuit.

[0009] Preferably, a servo motor is fixedly connected to the side wall of the fixed plate, and the output end of the servo motor passes through the side wall of the fixed plate and is fixedly connected to the rotating shaft.

[0010] Preferably, an external FBG sensor is fixedly embedded in the external positioning rod, and an internal FBG sensor is fixedly embedded in the internal positioning rod. The external FBG sensor, the internal FBG sensor, the pulse solenoid valve, the motor, and the servo motor are electrically connected through a PLC control circuit.

[0011] Preferably, a flow guide shroud is fixedly connected to the inner wall of the furnace body, and multiple exhaust ports are provided at the upper end of the furnace body.

[0012] Preferably, the upper end of the placement platform is provided with multiple stress relief grooves, the stress relief grooves are in a continuous S-shape, and the stress relief grooves are filled with flexible graphite felt.

[0013] Preferably, the furnace body has a feeding port on its side wall, and a furnace door is rotatably installed on the inner wall of the feeding port.

[0014] The present invention has the following beneficial effects: 1. By using the reverse spiral arrangement of the upper and lower spiral fan blades and the pulsed ammonia injection, intense vertical convection and radial shear force are formed in the furnace body. Combined with the unique Z-shaped drive shaft, the Coanda effect and Dean vortex in fluid mechanics are used to generate negative pressure adsorption force and micro cyclone pointing towards the workpiece at the shaft bend. This forcibly breaks the static gas film and concentration boundary layer on the workpiece surface, and also kneads active nitrogen atoms into deep holes and thread dead corners, improving nitriding efficiency and uniformity, and eliminating spots. 2. By pre-embedding FBG strain sensors in the outer positioning frame, the system can monitor the tensile strain of the workpiece due to its own weight in real time with micron-level accuracy. Once the workpiece is determined to enter the instability risk zone, the system automatically reduces the speed of the double helix fan to reduce the downward air pressure, and at the same time increases the frequency of the pulse solenoid valve to increase the overall gas pressure in the furnace. The uniform collision of gas molecules generates an isotropic supporting force, which lifts the lower part of the workpiece like an air cushion, reducing high-temperature creep sagging and bottom stress concentration. 3. By monitoring the expansion rate and temperature of the inner and outer walls of the workpiece in real time through internal and external FBG sensors, the system can intelligently switch cooling modes. When the inner hole is overheated, the servo motor drives the nozzle to turn downward at a 45-degree angle, creating a cold air pool at the bottom of the furnace. Utilizing thermal convection, the cold air rises naturally and flows through the inner hole, carrying away heat and achieving gentle and precise internal cooling. When the outer wall is overheated, the nozzle activates a high-frequency sine wave pulse, generating detached cold ammonia vortex rings. These high-energy cold bullets ignore the central airflow interference, directly impacting and swirling to cool the outer wall, achieving efficient external cooling. This precise temperature control with time-sharing and zone-sharing perfectly solves the problem of structural stress caused by the temperature difference between the inner and outer walls of thick-walled workpieces. Attached Figure Description

[0015] Figure 1 This is a three-dimensional structural diagram of a nitriding treatment device for a 42CrMo well completion tool assembly proposed in this invention; Figure 2 for Figure 1 Schematic diagram of the cross-sectional structure of the central furnace body; Figure 3 for Figure 2 Enlarged schematic diagram of the structure at point A; Figure 4 for Figure 2 Cross-sectional schematic diagram of the internal structure of the furnace body; Figure 5 for Figure 4 Enlarged schematic diagram of the structure at point B; Figure 6 for Figure 4 Enlarged schematic diagram of the structure at point C; Figure 7 for Figure 2 A schematic diagram of the jet assembly; Figure 8 for Figure 2 A schematic diagram of the structure of the central placement platform.

[0016] In the diagram: 1. Furnace body; 2. Support frame; 3. Placement platform; 4. Drive shaft; 5. Upper spiral fan blade; 6. Lower spiral fan blade; 7. Fixing plate; 8. Rotating shaft; 9. Mounting block; 10. Nozzle; 11. Air inlet pipe; 12. Pulse solenoid valve; 13. External positioning frame; 14. Mounting slot one; 15. External positioning rod; 16. Spring one; 17. Positioning column; 18. Mounting slot two; 19. Internal positioning rod; 20. Spring two; 21. Motor; 22. FBG strain sensor; 23. Servo motor; 24. External FBG sensor; 25. Internal FBG sensor; 26. Resistance band heater; 27. Flow guide; 28. Feed port; 29. ​​Furnace door; 30. Exhaust port; 31. Stress relief groove. Detailed Implementation

[0017] To make the above-mentioned objects, features, and advantages of the present invention more apparent and understandable, specific embodiments of the present invention will be described in detail below with reference to the accompanying drawings. Many specific details are set forth in the following description to provide a thorough understanding of the present invention. However, the present invention can be practiced in many other ways different from those described herein, and those skilled in the art can make similar modifications without departing from the spirit of the present invention. Therefore, the present invention is not limited to the specific embodiments disclosed below.

[0018] Reference Figures 1-8 A nitriding treatment device for 42CrMo well completion tool components, comprising a furnace body 1, and further comprising: Support 2 is fixedly connected to the bottom of the furnace body 1; The placement platform 3, which is fixedly connected to the upper end of the bracket 2, is used to place the well completion tool assembly. It is made of high-purity isostatic graphite material and can produce small deformations. The drive shaft 4 is rotatably connected to the top of the furnace body 1, and its shape is Z-shaped. Several upper spiral fan blades 5 are fixedly connected to the side wall of the drive shaft 4; Several lower spiral fan blades 6 are fixedly connected to the side wall of the drive shaft 4, and their spiral direction is opposite to that of the upper spiral fan blades 5, and they are located below the upper spiral fan blades 5; Motor 21 is fixedly connected to the upper end of furnace body 1, and its output end passes through the upper end of furnace body 1 and is fixedly connected to the transmission shaft 4. Motor 21 adopts a high-power variable frequency spindle motor. The jet assembly is located on the inner wall of the furnace body 1; The jet assembly includes: Several fixing plates 7 are fixedly connected to the inner wall of the furnace body 1; The rotating shaft 8 is rotatably connected to the side walls of two fixed plates 7 that are close to each other; Mounting block 9 is fixedly connected to the side wall of rotating shaft 8; The nozzle 10 is fixedly connected to the side wall of the mounting block 9 and is set at a 70-degree angle to the bottom of the furnace body 1 and the horizontal direction. The ammonia gas it sprays is directed towards the lower part of the well completion tool assembly. The air inlet pipe 11 is connected at one end to the nozzle 10 and at the other end to an external air pump. The air inlet pipe 11 is a flexible pipe that can deform. The pulse solenoid valve 12 is installed on the inner wall of the intake pipe 11.

[0019] A resistance band heater 26 is fixedly connected to the inner wall of the furnace body 1, and the resistance band heater 26 is located above the upper spiral fan blade 5.

[0020] A feeding port 28 is provided on the side wall of the furnace body 1, and a furnace door 29 is rotatably installed on the inner wall of the feeding port 28.

[0021] A positioning assembly is installed on the placement platform 3. The positioning assembly includes multiple outer positioning frames 13 fixedly connected to the upper end of the placement platform 3. The multiple outer positioning frames 13 are arranged in a circular array around the center of the placement platform 3. The side wall of the outer positioning frame 13 is provided with a mounting groove 14. An outer positioning rod 15 is slidably connected to the inner wall of the mounting groove 14. A spring 16 is fixedly connected between the inner wall of the mounting groove 14 and the outer positioning rod 15.

[0022] The positioning assembly also includes a positioning post 17 fixedly connected to the upper end of the placement platform 3. The side wall of the positioning post 17 has multiple mounting slots 18. Each mounting slot 18 has an inner positioning rod 19 slidably connected to its inner wall. A spring 20 is fixedly connected between the inner wall of the mounting slot 18 and the inner positioning rod 19.

[0023] Furthermore, the furnace door 29 is opened, and the well completion tool assembly is placed on the upper end of the placement platform 3 through the loading port 28. After placement, multiple outer positioning rods 15 will abut against the outer wall of the well completion tool assembly under the action of spring 16, while multiple inner positioning rods 19 will abut against the inner wall of the well completion tool assembly under the action of spring 20, thereby clamping and positioning the well completion tool assembly.

[0024] It should be noted that during the nitriding process, the completion tool assembly undergoes expansion deformation. Under the action of spring 16 and spring 20, the outer positioning rod 15 and the inner positioning rod 19 are always in contact with the outer wall and inner hole of the completion tool assembly, respectively, thus providing effective clamping.

[0025] Furthermore, the resistance band heater 26 is energized, and the motor 21 and external air pump are started simultaneously. The resistance band heater 26 heats the air above the upper spiral fan blade 5, while the air pump pumps external ammonia gas into the nozzle 10 through the air inlet pipe 11. The ammonia gas is then ejected from the nozzle 10 and sprayed out in the form of a pulse jet under the action of the pulse solenoid valve 12. The high-speed ammonia gas ejected each time has extremely strong penetrating power and entrainment ability. It violently entrains the surrounding gas, forming a large-scale strong turbulence in the furnace body 1. This strong tumbling and mixing can instantly break the gas film on the surface of the well completion tool assembly, allowing the temperature field and atmosphere field in the furnace body 1 to quickly reach a high degree of uniformity. In addition, the high-frequency pressure wave and turbulent pulsation brought by the pulse airflow can continuously smash high-concentration fresh ammonia gas onto the surface of the well completion tool assembly like a miniature wind hammer, promoting the adsorption and decomposition of ammonia gas on its surface. At the same time, the active substances produced by decomposition can diffuse into the matrix of the well completion tool assembly more quickly and deeply.

[0026] Furthermore, the rotation of motor 21 drives the transmission shaft 4 to rotate, which in turn drives the upper spiral fan blade 5 and the lower spiral fan blade 6 to rotate. Since the upper spiral fan blade 5 and the lower spiral fan blade 6 have opposite spiral directions, the rotation of the upper spiral fan blade 5 can press down the hot air in the upper part of the furnace body 1, while the lower spiral fan blade 6 can draw up the cold ammonia gas at the bottom of the furnace body 1. First, the two airflows collide, shear, and mix violently in the middle of the furnace body 1, allowing the high-temperature gas and the low-temperature gas to merge instantly. This controls the longitudinal temperature difference in the furnace body 1 within a very small range. The extremely small temperature difference ensures that all parts of the well completion tool assembly are heated synchronously, resulting in consistent expansion and contraction, and reducing the thermal stress on the well completion tool assembly during the nitriding process. The stable temperature ensures that the diffusion and reaction rates in every corner of the furnace body 1 remain synchronized, thus providing a favorable environment for nitriding. Secondly, the opposite spiral directions of the upper spiral blade 5 and the lower spiral blade 6 generate extremely strong radial shear force. This force disrupts the static gas film tightly adhering to the surface of the well completion tool assembly, forcibly incorporating fresh ammonia gas rich in nitrogen atoms into every threaded groove and deep hole of the well completion tool assembly, eliminating dead zones. Finally, the opposite spiral directions of the upper spiral blade 5 and the lower spiral blade 6 cause their respective pressure fields to cancel each other out in the central axis region, stabilizing the fluid pressure at the center of the furnace body 1 and providing a uniform lateral gas pressure support for the elongated well completion tool assembly.

[0027] It is worth mentioning that the U-shaped arrangement of the drive shaft 4 avoids interference with the well completion tool assembly inside the furnace body 1, enabling synchronous rotation of the upper spiral fan blade 5 and the lower spiral fan blade 6 on a single shaft, simplifying the internal structure of the furnace body 1. Furthermore, due to the U-shaped arrangement of the drive shaft 4, it forms a U-shape in the middle of the furnace body 1. When gas flows past the outer side of the U-shaped bend, according to the Coanda effect, the fluid tends to flow along the curved surface. Simultaneously, because the U-shaped cross-section changes the airflow direction, a low-pressure zone is formed on the concave surface of the U-shape, generating a negative pressure adsorption force pointing towards the well completion tool assembly. This negative pressure adsorption force re-presses the edge airflow that might otherwise detach from the surface of the well completion tool assembly back onto the workpiece. During the nitriding and heat preservation stage, this reduces the heat transfer on the surface of the well completion tool assembly. Boundary layers and concentration boundary layers allow active nitrogen atoms to penetrate deeper into the completion tool assembly, improving nitriding efficiency and uniformity. When the airflow makes a high-speed turn at the U-shape of the drive shaft 4, the pressure on the outer side of the drive shaft 4 will be higher than that on the concave side due to centrifugal force, creating a pressure difference. This pressure difference causes the fluid to generate one or more pairs of counter-rotating secondary flows on the cross-section, i.e., Dean vortices. Therefore, once the drive shaft 4 starts to rotate, each cross-section generates continuous micro-cyclones. These vortices, like countless brushes, continuously stir the flow field around the completion tool assembly, thoroughly dispersing the ammonia gas deposited in the furnace, preventing airflow short-circuiting, and ensuring a high degree of uniformity in the atmosphere of the microenvironment in which the completion tool assembly is located, reducing spots or soft spots caused by local atmosphere inhomogeneity.

[0028] An FBG strain sensor 22 is embedded in the side wall of the outer positioning frame 13. The FBG strain sensor 22, the pulse solenoid valve 12, and the motor 21 are electrically connected through a PLC control circuit.

[0029] It should be noted that the FBG strain sensor 22 uses an electroplating nickel process to metallize the bare optical fiber, then embeds it into the microgroove on the surface of the outer positioning frame 13, and finally covers it with a thin layer of high-temperature resistant alloy to ensure that it can withstand high temperature and thermal cycling.

[0030] Furthermore, during the nitriding process, when the completion tool assembly softens due to heat and bears its own weight, a complex stress distribution will occur inside. When the middle part of the completion tool assembly begins to sag due to its own weight, the lower surface will be stretched and the upper surface will be compressed. At this time, the FBG strain sensor 22 can capture the tiny tensile strain of the lattice on the lower surface of the completion tool assembly with micron-level precision. Once the detected tensile strain exceeds the preset threshold, it is determined that the completion tool assembly has entered the instability risk zone. At this time, the FBG strain sensor 22 will send a signal to control the motor 21 to slow down through the PLC control circuit, thereby reducing the rotation speed of the upper spiral fan blade 5 and the lower spiral fan blade 6. The speed is increased, thereby reducing the air pressure load on the upper surface of the well completion tool assembly, alleviating the bending stress in the middle of the well completion tool assembly, and the PLC control circuit will synchronously control the pulse solenoid valve 12 to increase the pulse frequency. When the pulse solenoid valve 12 works at high frequency, the gas pressure inside the furnace body 1 will rise as a whole, and the collision frequency and momentum transfer of gas molecules on the lower surface of the well completion tool assembly will increase sharply. Since the gas has fluidity, the pressure generated by molecular collision is uniform in all directions. It will form a uniformly distributed upward supporting force field on the lower surface of the well completion tool assembly, which will play a role in supporting the lower part of the well completion tool assembly, thereby reducing the sagging of the middle and lower part of the well completion tool assembly.

[0031] A servo motor 23 is fixedly connected to the side wall of the fixed plate 7. The output end of the servo motor 23 passes through the side wall of the fixed plate 7 and is fixedly connected to the rotating shaft 8.

[0032] An external FBG sensor 24 is fixedly embedded in the outer positioning rod 15, and an internal FBG sensor 25 is fixedly embedded in the inner positioning rod 19. The external FBG sensor 24, the internal FBG sensor 25, the pulse solenoid valve 12, the motor 21, and the servo motor 23 are electrically connected through a PLC control circuit.

[0033] It should be noted that the external FBG sensor 24 and the internal FBG sensor 25 can monitor the strain and temperature of the surface of the well completion tool assembly. This is existing technology and will not be described in detail here.

[0034] Furthermore, during the nitriding process, the external FBG sensor 24 and the internal FBG sensor 25 monitor the expansion rate and temperature of the outer wall and inner bore of the completion tool assembly in real time. When the expansion rate of the inner bore of the completion tool assembly is greater than that of the outer wall, and the temperature of the inner bore is greater than that of the outer wall, and the temperature difference exceeds a set threshold, the external FBG sensor 24 and the internal FBG sensor 25 control the motor 21 to slow down through the PLC control circuit, causing the upper spiral fan blade 5 and the lower spiral fan blade 6 to rotate at a low speed, and simultaneously control the servo motor 23 to rotate, driving the rotating shaft 8 to rotate, which in turn drives the mounting block 9 to rotate. The movement causes the nozzle 10 to rotate, adjusting its angle so that it is angled downwards at 45 degrees. This allows the ammonia gas to be sprayed directly into the bottom of the furnace body 1, rather than onto the outer surface of the well completion tool assembly. A cold gas pool is formed at the bottom of the furnace body 1. When the cold ammonia gas comes into contact with the lower end and the inner orifice of the well completion tool assembly, it is heated. According to the second law of thermodynamics, the gas, which becomes lighter when heated, will naturally rise along the vertical inner wall. Therefore, after entering the inner orifice, the cold ammonia gas will flow upwards along the inner wall, absorbing the heat from the inner wall and cooling it down.

[0035] Furthermore, when the expansion rate of the outer wall of the completion tool assembly is detected to be greater than that of the inner hole, and the temperature of the outer wall is greater than that of the inner hole, and the temperature difference exceeds the set threshold, the outer FBG sensor 24 and the inner FBG sensor 25 will control the motor 21 to slow down through the PLC control circuit, so that the upper spiral fan blade 5 and the lower spiral fan blade 6 rotate at low speed, and the pulse solenoid valve 12 is raised to high frequency, so that the nozzle 10 opens a high frequency sine wave pulse. This high frequency violent jet will continuously generate detached smoke ring-shaped cold ammonia bubbles at the outlet of the nozzle 10. Due to the low speed rotation of the upper spiral fan blade 5 and the lower spiral fan blade 6, these bubbles will not be suppressed by the downward airflow, and will rush straight towards the lower outer wall of the completion tool assembly like cold bullets, and then spiral upward along the outer wall, rapidly cooling the outer wall of the completion tool assembly.

[0036] A flow guide shroud 27 is fixedly connected to the inner wall of the furnace body 1. Multiple exhaust ports 30 are opened at the upper end of the furnace body 1. Solenoid valves are installed on the inner wall of the exhaust ports 30. When exhaust is required, the solenoid valves can be energized to open the exhaust ports 30 for exhaust.

[0037] It should be noted that when the airflow is pressed down, the guide shroud 27 can constrict the airflow and make it impact vertically downwards. When the airflow is pressed up, the guide shroud 27 collects the airflow, causing it to flow towards the exhaust port 30 for easy exhaust.

[0038] The upper end of the placement platform 3 is provided with multiple stress relief grooves 31. The stress relief grooves 31 are in a continuous S-shape and are filled with flexible graphite felt. This allows the placement platform 3 to generate controlled micro-elastic deformation when bearing heavy workpieces, thus avoiding compressive stress cracks at the bottom of the workpiece caused by rigid tops.

[0039] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any equivalent substitutions or modifications made by those skilled in the art within the scope of the technology disclosed in the present invention, based on the technical solution and inventive concept of the present invention, should be covered within the scope of protection of the present invention.

Claims

1. A device for nitriding treatment of 42CrMo well completion tool components, comprising a furnace body (1), characterized in that... , further comprising: a bracket (2), which is fixedly connected to the inner bottom of the furnace body (1); a placing table (3), which is fixedly connected to the upper end of the bracket (2) and used for placing a completion tool assembly, and is made of high-purity isostatic graphite material; a transmission shaft (4), which is rotatably connected to the inner top of the furnace body (1) and is in a zigzag shape, with the U-shaped bent section of the transmission shaft (4) located in the middle of the furnace body (1) directly facing the workpiece area; a plurality of upper spiral fan blades (5), which are fixedly connected to the side wall of the transmission shaft (4); a plurality of lower spiral fan blades (6), which are fixedly connected to the side wall of the transmission shaft (4), have a spiral direction opposite to that of the upper spiral fan blades (5), and are located below the upper spiral fan blades (5); a motor (21), which is fixedly connected to the upper end of the furnace body (1), and the output end of which penetrates through the upper end of the furnace body (1) and is fixedly connected to the transmission shaft (4); an air injection assembly, which is arranged on the inner wall of the furnace body (1); the air injection assembly comprises: a plurality of fixing plates (7), which are fixedly connected to the inner wall of the furnace body (1); a rotating shaft (8), which is rotatably connected to the side walls of the two adjacent fixing plates (7); a mounting block (9), which is fixedly connected to the side wall of the rotating shaft (8); a spray head (10), which is fixedly connected to the side wall of the mounting block (9) and is arranged at an angle of 70 degrees to the horizontal direction towards the inner bottom of the furnace body (1); an air inlet pipe (11), one end of which is communicated with the spray head (10), and the other end of which is fixedly connected to an external air pump; a pulse solenoid valve (12), which is mounted on the inner wall of the air inlet pipe (11); a positioning assembly is mounted on the placing table (3), the positioning assembly comprises a plurality of outer positioning frames (13) fixedly connected to the upper end of the placing table (3), the plurality of outer positioning frames (13) are arranged in an annular array around the center of the placing table (3), a first mounting groove (14) is formed in the side wall of the outer positioning frame (13), an outer positioning rod (15) is slidably connected to the inner wall of the first mounting groove (14), and a first spring (16) is fixedly connected between the inner wall of the first mounting groove (14) and the outer positioning rod (15); the positioning assembly further comprises a positioning column (17) fixedly connected to the upper end of the placing table (3), a plurality of second mounting grooves (18) are formed in the side wall of the positioning column (17), an inner positioning rod (19) is slidably connected to the inner wall of each second mounting groove (18), and a second spring (20) is fixedly connected between the inner wall of the second mounting groove (18) and the inner positioning rod (19); an FBG strain sensor (22) is embedded in the side wall of the outer positioning frame (13), and the FBG strain sensor (22), the pulse solenoid valve (12) and the motor (21) are electrically connected through a PLC control circuit; a servo motor (23) is fixedly connected to the side wall of the fixing plate (7), and the output end of the servo motor (23) penetrates through the side wall of the fixing plate (7) and is fixedly connected to the rotating shaft (8); An external FBG sensor (24) is fixedly embedded in the external positioning rod (15), and an internal FBG sensor (25) is fixedly embedded in the internal positioning rod (19). The external FBG sensor (24), the internal FBG sensor (25), the pulse solenoid valve (12), the motor (21), and the servo motor (23) are electrically connected through a PLC control circuit.

2. The equipment for nitriding treatment of 42CrMo well completion tool components according to claim 1, characterized in that, A resistance band heater (26) is fixedly connected to the inner wall of the furnace body (1), and the resistance band heater (26) is located above the upper spiral fan blade (5).

3. The equipment for nitriding treatment of 42CrMo well completion tool components according to claim 1, characterized in that, The inner wall of the furnace body (1) is fixedly connected with a flow guide hood (27), and the upper end of the furnace body (1) is provided with multiple exhaust ports (30).

4. The equipment for nitriding treatment of 42CrMo well completion tool components according to claim 1, characterized in that, The upper end of the placement platform (3) is provided with multiple stress relief grooves (31), the stress relief grooves (31) are in a continuous S-shape, and the stress relief grooves (31) are filled with flexible graphite felt.

5. The equipment for nitriding treatment of 42CrMo well completion tool components according to claim 1, characterized in that, The furnace body (1) has a feeding port (28) on its side wall, and a furnace door (29) is rotatably installed on the inner wall of the feeding port (28).

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