Special machine for annealing treatment of long cylinder

Abstract

The invention relates to the technical field of pipe heat treatment, and discloses a special machine for annealing treatment of a long cylinder. The electromagnetic heating module is arranged on the rack and used for conducting heating treatment on the welding position of the pipe fitting; the clamping module is arranged on the rack and used for clamping and fixing the pipe fitting and driving the pipe fitting to rotate; the data acquisition module is used for acquiring physical parameters of the pipe fitting, including the length L, the diameter D and the thickness delta; and the control module is in signal connection with the electromagnetic heating module, the clamping module and the data acquisition module. By integrating the electromagnetic heating module, the clamping module, the data acquisition module and the control module, efficient and accurate annealing treatment on workpieces is realized. Through introduction of the data acquisition module, annealing process parameters can be dynamically adjusted according to physical parameters of a workpiece, and the flexibility and adaptability of annealing treatment are improved.

Description

Technical Field

[0001] This invention relates to the field of tube heat treatment technology, and more specifically, to a special machine for long tube annealing. Background Technology

[0002] Friction welding is a highly efficient material joining technology widely used in the assembly of end caps in the manufacturing of seamless steel pipes. This process utilizes the heat generated by high-speed rotating friction to bring the contact surfaces to a plastic state, achieving metallurgical bonding under upsetting pressure. However, residual stress generated during welding significantly reduces the fatigue strength and dimensional stability of the components; therefore, post-weld annealing is necessary to eliminate stress. The annealing process involves heating the welded area to above the recrystallization temperature of the steel (typically 600-800℃), holding it at that temperature for an appropriate time, and then slowly cooling it. This promotes lattice recombination, releasing internal stress and restoring the material's mechanical properties and service life.

[0003] Currently, although traditional annealing equipment has achieved a certain degree of automation, its automation level is still relatively low. Especially when processing workpieces of different diameters and lengths, although manual handling and fixing are unnecessary, frequent manual adjustments to heating positions and process parameters are still required, resulting in long changeover times. Furthermore, the fixed-speed rotation of the pipes can easily lead to uneven heating of large-diameter pipes, causing significant fluctuations in residual stress relief rates. Simultaneously, the functions of each automated unit are relatively independent, lacking collaborative operation capabilities, and process parameters largely rely on operator experience for setting, resulting in unstable annealing effects and difficulty in meeting the production requirements of high-precision pipes.

[0004] Therefore, there is an urgent need for an annealing equipment that can adapt to the needs of automated production in order to achieve efficient and precise annealing. Summary of the Invention

[0005] The purpose of this invention is to provide a special machine for long tube annealing to solve the above-mentioned technical problems.

[0006] The present invention solves the above-mentioned technical problems through the following technical solutions: This invention provides a special machine for long tube annealing, comprising: frame; The electromagnetic heating module, mounted on the frame, is used to heat the welded joints of pipe fittings. The clamping module, located on the frame, is used to clamp and fix the pipe fittings and drive the pipe fittings to rotate. The data acquisition module is used to obtain the physical parameters of the pipe fittings, including length. L ,diameter D and thickness δ ; The control module is connected to the electromagnetic heating module, clamping module, and data acquisition module via signals, and is configured as follows: a. Calculate the thermal property index Q based on physical parameters; b. Based on the thermal property index Q, the annealing process parameters are dynamically generated, including the target temperature T of the electromagnetic heating module, the annealing duration t, and the tube rotation speed ω of the clamping module; c. Send control commands to the electromagnetic heating module and the clamping module so that the electromagnetic heating module maintains the temperature T within time t, and the clamping module drives the pipe to rotate continuously at a speed ω.

[0007] Preferably, the formula for calculating the thermophysical property index in step a is as follows: , among which, among which, ρ For the density of the material, c p This represents the specific heat capacity of the material.

[0008] Preferably, the target temperature T is determined by the formula Calculate; the rotational speed ω Through formula calculate.

[0009] Preferably, the data acquisition module includes a laser scanning unit for non-contact measurement of L and D, an ultrasonic thickness measuring unit for detecting δ, and a temperature measuring unit for real-time measurement of the heating temperature of the electromagnetic heating module.

[0010] Preferably, the control module is further configured to: acquire temperature data uploaded by the temperature measurement unit in real time during the heating process of the electromagnetic heating module, and dynamically adjust the output power of the electromagnetic heating module when the actual temperature deviates from T by more than a threshold.

[0011] Preferably, the electromagnetic heating module includes an electromagnetic heating mechanism slidably mounted on a frame and a lead screw transmission mechanism for driving the linear movement of the electromagnetic heating mechanism. The electromagnetic heating mechanism includes an annular induction coil.

[0012] Preferably, there are two electromagnetic heating mechanisms and two lead screw transmission mechanisms, with the two electromagnetic heating mechanisms symmetrically distributed on both sides of the top of the frame.

[0013] Preferably, the clamping module includes a lifting mechanism, a jacking mechanism symmetrically arranged on both sides of the lifting mechanism, and a second lead screw transmission mechanism for driving the linear movement of the two jacking mechanisms, wherein one of the jacking mechanisms is equipped with a rotary motor.

[0014] Preferably, the jacking mechanism includes a movable seat that slides on the frame and a conical top block that rotates on the movable seat. The screw drive mechanism is threadedly connected to the bottom of the movable seat, and the rotating end of the rotary motor is connected to the conical top block.

[0015] Preferably, the lifting mechanism includes an electric push rod fixed to the frame and a clamp fixed to the top of the electric push rod.

[0016] The beneficial effects of this invention are as follows: This invention achieves efficient and precise annealing of workpieces by integrating an electromagnetic heating module, a clamping module, a data acquisition module, and a control module. The introduction of the data acquisition module allows for dynamic adjustment of annealing process parameters based on the workpiece's physical parameters, improving the flexibility and adaptability of the annealing process. Furthermore, the intelligent control module not only enables precise control of the annealing process but also allows for dynamic adjustments based on real-time temperature feedback, ensuring the stability of the annealing temperature. Attached Figure Description

[0017] Figure 1 This is a schematic diagram of the structure of a special machine for long-tube annealing provided by the present invention; Figure 2 This is a schematic diagram of the jacking mechanism in a special machine for long tube annealing provided by the present invention; Figure 3 This is a schematic diagram of the electromagnetic heating mechanism in a long-tube annealing machine provided by the present invention; Figure 4 This is a schematic diagram of the lifting mechanism in a special machine for long tube annealing provided by the present invention; Figure 5 This is a block diagram showing the relationship between the modules in a long-tube annealing machine provided by the present invention; Figure 6 This is a graph showing the relationship between target temperature and heat capacity in a long-tube annealing machine provided by the present invention; Figure 7 This is a graph showing the relationship between annealing time and heat capacity in a long-tube annealing machine provided by the present invention.

[0018] In the diagram: 1. Frame; 2. Electromagnetic heating mechanism; 21. Ring induction coil; 4. Screw drive mechanism one; 5. Lifting mechanism; 51. Electric push rod; 52. Clamping seat; 6. Pushing mechanism; 61. Moving seat; 62. Top block; 63. Rotary motor; 7. Screw drive mechanism two. Detailed Implementation

[0019] The subject matter described herein will now be discussed with reference to exemplary embodiments. It should be understood that these embodiments are discussed only to enable those skilled in the art to better understand and implement the subject matter described herein, and changes may be made to the function and arrangement of the elements discussed without departing from the scope of this specification. Various processes or components may be omitted, substituted, or added as needed in the examples. Furthermore, features described in some examples may be combined in other examples.

[0020] Please refer to the following: Figures 1 to 2 A special machine for long tube annealing includes: a frame 1, an electromagnetic heating module, a clamping module, a data acquisition module, and a control module. The electromagnetic heating module, mounted on the frame 1, is mainly used for heating the welded joints of the steel pipe. The electromagnetic heating module includes an electromagnetic heating mechanism 2 slidably mounted on the frame 1 and a screw drive mechanism 4 for driving the linear movement of the electromagnetic heating mechanism 2. The electromagnetic heating mechanism 2 includes a ring-shaped induction coil to adapt to the shape of the steel pipe and uniformly heat the gaps in the pipe.

[0021] The clamping module is mounted on the frame 1 and is mainly used to clamp and fix the workpiece, and can drive the workpiece to rotate, so that the gap in the steel pipe is heated evenly. The clamping module includes a lifting mechanism 5, a jacking mechanism 6 symmetrically arranged on both sides of the lifting mechanism 5, and a second lead screw transmission mechanism 7 for driving the linear movement of the two jacking mechanisms 6. Both the first lead screw transmission mechanism 4 and the second lead screw transmission mechanism 7 are composed of a servo motor and a transmission lead screw. One of the jacking mechanisms 6 is equipped with a rotary motor 63, making this jacking mechanism 6 the active rotating structure, and the other jacking mechanism 6 the driven structure. The jacking mechanism 6 includes a movable seat 61 that slides on the frame 1 and a conical top block 62 that rotates on the movable seat 61. The second lead screw transmission mechanism 7 is threadedly connected to the bottom of the movable seat 61, and the rotating end of the rotary motor 63 is connected to the conical top block 62. The lifting mechanism 5 includes an electric push rod 51 fixed on the frame 1 and a clamping seat 52 fixed to the top of the electric push rod 51.

[0022] The data acquisition module is used to acquire the physical parameters of the workpiece. It includes a laser scanning unit for non-contact measurement of the length L and diameter D of the steel pipe (which can use a line laser sensor (model LJ-V7080)), an ultrasonic thickness measuring unit for the wall thickness δ of the steel pipe (which can use an ultrasonic sensor, 5MHz probe, measurement range 5-50mm, 12 points are taken at equal intervals along the circumference to measure the wall thickness δ and take the average value), and a temperature measuring unit for real-time measurement of the heating temperature of the electromagnetic heating module. The laser scanning unit, ultrasonic thickness measuring unit and temperature measuring unit are all located on the frame 1.

[0023] The control module is connected to the electromagnetic heating module, clamping module, and data acquisition module via signals, and is configured as follows: a. Obtain the physical parameters uploaded by the data acquisition module, and according to the formula Calculate the thermal property index (heat capacity) Q, where, ρ For the density of the material, c p This represents the specific heat capacity of the material.

[0024] b. Based on the thermal property index Q, the annealing process parameters are dynamically generated, including the target temperature T of the electromagnetic heating module, the annealing duration t, and the workpiece rotation speed ω of the clamping module.

[0025] The target temperature T is obtained through the formula: The process involves generating the following: T0 is the basic annealing temperature, ranging from 620 to 780℃; K is the temperature compensation coefficient, ranging from 40 to 60; and Q0 is the heat capacity reference value, ranging from 800 to 1200 kJ / K.

[0026] The formula for the target temperature T was obtained by fitting experimental data. Experiments revealed a logarithmic relationship between the heat capacity Q and the optimal annealing temperature. As the heat capacity Q increases, due to the increase in thermal inertia, a higher temperature is required to ensure sufficient annealing in the weld area. This was obtained through fitting a large amount of experimental data, such as... Figure 6 As shown.

[0027] Rotational speed ω is expressed by the formula: generate, β The possible values ​​are as follows:

[0028] In the formula, ω 0 The reference rotational speed is 8-12 RPM, and D is the outer diameter of the workpiece in mm. α The pipe diameter attenuation index has a value of 0.2-0.4. The rotational speed was determined based on ensuring uniform heating of the steel pipe surface. Experiments showed that the rotational speed is exponentially related to the steel pipe diameter. The larger the diameter, the lower the rotational speed required to achieve the same surface linear velocity. Furthermore, for large-diameter steel pipes, due to the increased heat transfer path, the rotational speed needs to be appropriately reduced to increase the heating time.

[0029] Annealing time t is obtained through the formula Calculate, where, γ This is a time coefficient, with a value range of 100-150. This is derived from the diffusion kinetics model.

[0030] Annealing time is proportional to the square root of the heat capacity. This is because the heat diffusion time is proportional to the square of the workpiece size, while the heat capacity is proportional to the volume (i.e., the cube of the size), therefore time is proportional to the square root of the heat capacity. This is obtained through fitting experimental data, such as... Figure 7 As shown.

[0031] c. Send control commands to the electromagnetic heating module and the clamping module so that the electromagnetic heating module maintains the temperature T within time t, and the clamping module drives the workpiece to rotate continuously at a speed ω.

[0032] The control module is also configured to: acquire temperature data uploaded by the temperature measurement unit in real time during the heating process of the electromagnetic heating module, and dynamically adjust the output power of the electromagnetic heating module when the actual temperature deviates from T by more than the threshold.

[0033] It should be noted that regarding thermal property indicators... Q The derivation of the calculation formula is as follows: First, thermal properties Q It represents the amount of heat required for a unit temperature change, and its physical essence is the heat capacity of the workpiece. Where m is the mass of the workpiece. c p The specific heat capacity of the material; The mass m of the workpiece can be calculated using the workpiece's volume V and the material's density ρ: ; For a steel pipe, its volume is the volume of the outer cylinder minus the volume of the inner cylinder: ; The volume of the outer cylinder is: ; Volume of inner cylinder (inner diameter is) )for: ; Finally, heat capacity ; Since the units for length, diameter, and wall thickness are millimeters (mm), while the unit for density is kg / m³. 3 The volume unit needs to be converted to cubic meters (m³). 3 ), because 1m 3 =10 -9 mm 3 Therefore, the final result is:

[0034] The material is 45# steel (k=2.775×10). -6 ρ=7850kg / m 3 c p Taking (=0.45) as an example, the process of implementing the above scheme is as follows: The robotic arm places the steel pipe to be annealed onto the clamp 52 of the lifting mechanism 5. The electric push rod 51 is activated, causing the clamp 52 to rise until the steel pipe is clamped by the conical top blocks 62 of the two jacking mechanisms 6. Subsequently, the steel pipe model is manually input, and the control module automatically searches for the corresponding parameter data in the database. The laser scanning unit and ultrasonic thickness measurement unit then obtain the steel pipe's length L=5800mm, diameter D=219mm, and wall thickness δ=12.5mm. Assume T 0= 700℃, K=50, Q0=1000kJ / K, given D=219mm≤300mm, so β=1.0; assume ω0=10RPM, α=0.3, γ=120s / kJ / K; The measurement results are then uploaded to the control module, which calculates the thermal property index Q=1661.90kJ / k based on the received physical parameters using a preset formula.

[0035] Next, the control module dynamically generates annealing process parameters based on the thermal property index Q through corresponding functions, including the target temperature of the electromagnetic heating module T=711.03℃, the annealing duration t=4892.4 seconds, and the steel pipe rotation speed of the clamping module ω=1.72 RPM.

[0036] After the parameters are set, the control module sends control commands to the electromagnetic heating module and the clamping module. The electromagnetic heating module starts, and its induction coil begins to heat up. Driven by the lead screw transmission mechanism 4, the electromagnetic heating mechanism 2 moves linearly to the welded area of ​​the steel pipe for uniform heating. At the same time, the rotary motor 63 of the clamping module drives the conical top block 62 and the steel pipe to rotate, ensuring that the gaps in the steel pipe are heated evenly.

[0037] During the heating process, the temperature measurement unit measures the heating temperature of the electromagnetic heating module in real time and uploads the temperature data to the control module. The control module dynamically adjusts the output power of the electromagnetic heating module based on the deviation between the real-time temperature and the target temperature T to maintain temperature stability. Once the heating time reaches the preset annealing duration t, the electromagnetic heating module stops heating, and the clamping module also stops driving the steel pipe to rotate, completing the annealing process.

[0038] As can be seen from the above solution, the technical effects of the present invention are as follows: This invention achieves efficient and precise annealing of workpieces by integrating an electromagnetic heating module, a clamping module, a data acquisition module, and a control module. The introduction of the data acquisition module allows for dynamic adjustment of annealing process parameters based on the workpiece's physical parameters, improving the flexibility and adaptability of the annealing process. The intelligent control module not only achieves precise control of the annealing process but also dynamically adjusts based on real-time temperature feedback, ensuring the stability of the annealing temperature. Compared with traditional annealing devices, this invention has the advantages of compact structure, simple operation, and good annealing effect, meeting the needs of automated production and possessing broad application prospects.

[0039] The embodiments of the present invention have been described above, but the present invention is not limited to the specific embodiments described above. The specific embodiments described above are merely illustrative and not restrictive. Those skilled in the art can make many other forms under the guidance of the present invention, all of which are within the protection scope of the present invention.

Claims

1. A special machine for long tube annealing, characterized in that, include: frame; The electromagnetic heating module, mounted on the frame, is used to heat the welded joints of pipe fittings. The clamping module, located on the frame, is used to clamp and fix the pipe fittings and drive the pipe fittings to rotate. The data acquisition module is used to obtain the physical parameters of the pipe fitting, including length L, diameter D, and thickness δ; The control module is connected to the electromagnetic heating module, clamping module, and data acquisition module via signals, and is configured as follows: a. Calculate the thermal property index Q based on physical parameters; b. Based on the thermal property index Q, the annealing process parameters are dynamically generated, including the target temperature T of the electromagnetic heating module, the annealing duration t, and the tube rotation speed ω of the clamping module; c. Send control commands to the electromagnetic heating module and the clamping module so that the electromagnetic heating module maintains the temperature T within time t, and the clamping module drives the pipe to rotate continuously at a speed ω.

2. The long-tube annealing machine according to claim 1, characterized in that, The formula for calculating the thermophysical property index in step a is as follows: Where, ρ is the density of the material, c p This represents the specific heat capacity of the material.

3. The long-tube annealing machine according to claim 1, characterized in that, In step b, the target temperature T is determined by the formula Calculate; the rotational speed ω Through formula calculate.

4. The long-tube annealing machine according to claim 1, characterized in that, The data acquisition module includes a laser scanning unit for non-contact measurement of L and D, an ultrasonic thickness measuring unit for detecting δ, and a temperature measuring unit for real-time measurement of the heating temperature of the electromagnetic heating module.

5. A special machine for long-tube annealing according to claim 4, characterized in that, The control module is also configured to: acquire temperature data uploaded by the temperature measurement unit in real time during the heating process of the electromagnetic heating module, and dynamically adjust the output power of the electromagnetic heating module when the actual temperature deviates from T by more than the threshold.

6. A special machine for long-tube annealing according to claim 1, characterized in that, The electromagnetic heating module includes an electromagnetic heating mechanism slidably mounted on a frame and a lead screw transmission mechanism for driving the linear movement of the electromagnetic heating mechanism. The electromagnetic heating mechanism includes a ring-shaped induction coil.

7. A special machine for long-tube annealing according to claim 6, characterized in that, Both the electromagnetic heating mechanism and the lead screw transmission mechanism are provided in twos, with the two electromagnetic heating mechanisms symmetrically distributed on both sides of the top of the frame.

8. A special machine for long-tube annealing according to claim 1, characterized in that, The clamping module includes a lifting mechanism, a jacking mechanism symmetrically arranged on both sides of the lifting mechanism, and a second lead screw transmission mechanism for driving the linear movement of the two jacking mechanisms, wherein one of the jacking mechanisms is equipped with a rotary motor.

9. A special machine for long-tube annealing according to claim 8, characterized in that, The jacking mechanism includes a movable seat that slides on the frame and a conical top block that rotates on the movable seat. The screw drive mechanism is threadedly connected to the bottom of the movable seat, and the rotating end of the rotary motor is connected to the conical top block.

10. A special machine for long-tube annealing according to claim 8, characterized in that, The lifting mechanism includes an electric push rod fixed to the frame and a clamp fixed to the top of the electric push rod.

Images