Temperature compensation method and special device during rolling of super large rings for aerospace use

Abstract

The invention discloses a method and a special device for temperature compensation during the rolling process of aerospace super-large rings, which belongs to the field of ring rolling. The specific method is as follows: during the rolling process of super-large rings, an infrared temperature sensor placed outside the workpiece monitors the surface temperature of the ring and outputs a temperature signal. When the temperature value output by the infrared temperature sensor is lower than the set minimum rolling temperature, the feeding speed of the ring rolling is reduced, and the electromagnetic induction heater surrounding the ring starts to work to induction heat the ring, thereby compensating the ring rolling temperature; when the temperature value output by the infrared temperature sensor is higher than the set maximum rolling temperature, the electromagnetic induction heater stops working, the temperature compensation work ends, and the ring rolling resumes the original feeding speed. In this way, the temperature of the ring is always kept within the rolling temperature range, thereby improving the quality of the product.

Description

Technical Field

[0001] The invention belongs to the field of ring rolling, and more specifically, relates to a method for temperature compensation during the rolling process of super-large rings for aerospace use. Technical Background

[0002] Ring rolling, also known as ring rolling and hole expansion, belongs to the plastic forming technology. By using the high-speed rotating rollers in the annular expansion device to continuously pressurize the ring blank, the wall thickness of the ring blank gradually decreases during the rotation process. Ring rolling has many technical and economic advantages such as high production efficiency, high precision, high quality, cost saving and high efficiency, saving energy and reducing materials, and bringing low production costs. At present, large rings are widely used in various fields of industrial manufacturing such as wind power equipment manufacturing, nuclear reactors, aerospace, etc. due to their good mechanical properties, among which they are more widely used in the aerospace field.

[0003] However, due to the long rolling time of large rings, the temperature of the rings in the later stage of rolling cannot meet the rolling requirements, thus affecting the product quality. Therefore, temperature compensation of the rings during the rolling process is indispensable. Secondary heating of the rings during the rolling process will waste time and energy. At the same time, the semi-finished rings are large in size, and the requirements for the size of the heating furnace are also high, which is difficult to achieve. Therefore, we need to seek a new method for temperature compensation of the rings during rolling. Summary of the invention

[0004] In order to solve the existing technical deficiencies, the present invention provides a method for temperature compensation during the rolling process of super-large rings for aerospace use.

[0005] In order to achieve the above-mentioned purpose, the present invention adopts the following technical scheme.

[0006] A method for temperature compensation during the rolling process of aerospace super-large rings includes the following steps:

[0007] (1) Before rolling begins, an infrared temperature sensor is placed on the outside of the ring to monitor the temperature of the ring in real time during the ring rolling process;

[0008] (2) During the rolling process, when the monitored temperature value is lower than the set minimum rolling temperature, the feed speed of the ring rolling is reduced, and the electromagnetic induction heater surrounding the ring starts to work to compensate the temperature of the ring;

[0009] (3) When the monitored temperature value is higher than the set maximum rolling temperature, the electromagnetic induction heater stops working, the feed speed of the ring rolling is restored to the original value, and the temperature compensation ends.

[0010] Furthermore, the infrared temperature sensor in step (1) can output a temperature signal in real time, and its measurement error is within ±1%.

[0011] Furthermore, the temperature signal output by the infrared temperature sensor can be displayed in real time on a display.

[0012] Further, the ring rolling feed speed of step (2) is reduced to Where R D is the radius of the driving roller, R is the instantaneous outer diameter of the ring, r is the instantaneous inner diameter of the ring, and R M Core roller radius, n D =wD / 2π,w D is the angular velocity.

[0013] Furthermore, the electromagnetic induction heater described in step (2) can move as the diameter of the ring increases, and the distance between the heating coil of the electromagnetic induction heater and the surface of the ring is fixed.

[0014] The heating frequency of the electromagnetic induction heater is fc = 4×10 8 ρ / μa 2 , where ρ is the resistivity of the material in ohms / cm, μ is the relative magnetic permeability of the workpiece, and a is the thickness of the material.

[0015] Furthermore, the heating power of the electromagnetic induction heater = (kg / hour production capacity) x (kilowatt-hour / kg) x (efficiency factor), where (kilowatt-hour / kg) is the heat capacity, which refers to the total energy required to heat the material to a specific temperature.

[0016] A device for temperature compensation in the rolling process of a super-large ring for aerospace use comprises a transversely arranged "I"-shaped track, an electromagnetic induction heater installed on the "I"-shaped guide rail and capable of freely moving transversely along the track, and a distance measuring device installed on the electromagnetic induction heater; the electromagnetic induction heater comprises a C-shaped heating coil and a motor and a signal processor module installed on the upper part of the C-shaped heating coil, the C-shaped heating coil is connected with the motor and the signal processor module through a connecting rod, a clamp is provided on the top of the motor and the signal processor module, and the clamp is clamped on the "I"-shaped track; a pulley is provided on the clamp, which rotates under the drive of the motor, thereby driving the electromagnetic induction heater to move along the "I"-shaped track; the distance measuring device is fixed on the inner side of the C-shaped heating coil of the electromagnetic induction heater, and the distance between the electromagnetic induction heater and the side of the annular workpiece is measured by an infrared probe provided on the distance measuring device, and the measured data is transmitted to the motor and the signal processor module on the upper part of the coil, so as to control the opening and closing of the motor switch, so that the distance between the electromagnetic induction heater and the annular workpiece is kept constant.

[0017] Furthermore, the two ends of the "I"-shaped track are fixed on the first bracket and the second bracket on the ground. The first bracket and the second bracket are fixed together with the "I"-shaped track at the connection point by bolts.

[0018] Furthermore, the clamp is a C-shaped structure with an open top, and is used for clamping on the "I"-shaped track.

[0019] The beneficial effect of the present invention is that the present invention quickly compensates the temperature of the ring during the rolling process of the super-large ring through the electromagnetic induction heater, so that the temperature of the ring is always within the rolling temperature range, reducing the defects of the ring caused by the rolling temperature not meeting the requirements, and improving product quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0020] Figure 1 It is a flow chart of the present invention.

[0021] Figure 2 This is a simplified diagram of the positional relationship between the electromagnetic induction heater, the rolling mill and the ring.

[0022] Figure 3 Schematic diagram of the fixed connection of the ring on the rolling mill.

[0023] In the figure, 1. the first bracket, 2. the second bracket, 3. the "I"-shaped track, 4. the C-shaped heating coil, 5. the motor and signal processor module, 6. the fixture, 7. the distance measuring device, 8. the ring, 9. the driving roller, 10. the core roller, and 11. the cone roller. DETAILED DESCRIPTION

[0024] See attached Figure 1 The temperature compensation method for ring rolling of the present invention is: (1) before rolling begins, an infrared temperature sensor is placed on the outside of the ring to monitor the temperature of the ring in real time during the ring rolling process; the infrared temperature sensor can output a temperature signal in real time, and its measurement error is between ±1%, and the temperature signal can be displayed in real time on a display.

[0025] (2) During the rolling process, when the monitored temperature value is lower than the set minimum rolling temperature, the feed speed of the ring rolling is reduced, and the electromagnetic induction heater surrounding the ring starts to work to compensate the temperature of the ring;

[0026] In the present invention, the ring rolling feed speed is reduced to Where R D is the radius of the driving roller, R is the instantaneous outer diameter of the ring, r is the instantaneous inner diameter of the ring, and R M Core roller radius, n D =w D / 2π,w D is the angular velocity.

[0027] (3) When the monitored temperature value is higher than the set maximum rolling temperature, the electromagnetic induction heater stops working, the feed speed of the ring rolling is restored to the original value, and the temperature compensation ends.

[0028] When the present invention performs temperature compensation on rings of different diameters, the electromagnetic induction heater can be adjusted as the diameter of the ring changes, and the distance between the heating coil of the electromagnetic induction heater and the surface of the ring should be fixed.

[0029] The heating frequency f of the electromagnetic induction heater of the present invention is c =4×10 8 ρ / μa 2 , where ρ is the resistivity of the material in ohms / cm, μ is the relative magnetic permeability of the workpiece, and a is the thickness of the material. The heating power of the electromagnetic induction heater = (kg / hour production capacity) x (kilowatt-hour / kg) x (efficiency factor), where (kilowatt-hour / kg) is the heat capacity, which refers to the total energy required to heat the material to a specific temperature.

[0030] In the present invention, the temperature compensation during the ring rolling process is achieved by a heating device, see the attached Figure 2 The heating device comprises an I-shaped guide rail 3 installed above the rolling mill, an electromagnetic induction heater installed on the I-shaped guide rail 3 and capable of freely moving laterally along the track, and a distance measuring device 7 installed on the electromagnetic induction heater. Figure 3 , the rings installed on the rolling mill are clamped and fixed by the driving roller, the core roller and the cone roller, and driven to rotate by the driving roller. The two ends of the "I"-shaped track 3 of the device of the present invention are fixed on the first bracket 1 and the second bracket 2 on the ground, and the two brackets are fixed together with the "I"-shaped track 3 by bolts, which is convenient for disassembly; the electromagnetic induction heater in the present invention is composed of a C-shaped heating coil 4 and a motor and signal processor module 5 installed on the upper part of the C-shaped heating coil 4. After the C-shaped heating coil 4 is energized, an eddy current is formed to heat the rings on the rolling mill. The C-shaped heating coil 4 is connected to the motor and signal processor module 5 through a connecting rod. A clamp 6 is provided on the top of the motor and signal processor module 5, and the electromagnetic induction heater is clamped on the "I"-shaped track through the clamp 6. The clamp 6 in the present invention is a C-shaped structure with an open top, which is used to be clamped on the "I"-shaped track 3. The fixture 6 is provided with a pulley, which can rotate under the drive of the motor, thereby driving the electromagnetic induction heater to move along the "I"-shaped track 3; the distance measuring device 7 of the present invention is fixed on the inner side of the C-shaped heating coil 4 of the electromagnetic induction heater, and the distance between it and the side of the annular workpiece is measured by the infrared probe provided on the distance measuring device and the measured data is transmitted to the motor and signal processor module 5 on the upper part of the coil for controlling the opening and closing of the motor switch, so that the distance between the electromagnetic induction heater and the annular workpiece is kept constant.

[0031] The present invention is further described below in conjunction with specific embodiments.

[0032] Example 1: A method for temperature compensation during the rolling process of large 2219 aluminum alloy rings for aerospace use.

[0033] The rolling parameters of the rings are shown in the following table:

[0034]

[0035] The specific temperature compensation process is as follows:

[0036] (1) A billet with a size of 3770 mm*2570 mm*480 mm was heated to 510°C and placed on a rolling mill. Before rolling began, an infrared temperature sensor was placed on the outside of the billet to monitor the temperature of the ring in real time during the rolling process.

[0037] (2) During the rolling process, when the ring temperature is monitored to be lower than 450°C, the feed speed of the core roller begins to decrease, and the electromagnetic induction heater starts to work to start temperature compensation of the ring.

[0038] (3) During the temperature compensation process, when it is detected that the ring temperature is higher than 520°C, the electromagnetic induction heater stops working, the temperature compensation ends, and the core roller resumes the original feed speed.

[0039] The measurement error of the infrared temperature sensor in step (1) is between ±5.2°C.

[0040] The feed rate in step (2) was reduced to 0.2 mm / s.

[0041] The heating frequency of the electromagnetic heater in step (2) is 50 Hz.

[0042] The heating power of the electromagnetic induction heater in step (2) is 1000Kw.

[0043] Through temperature compensation during the rolling process, quality has been significantly improved and defects have been significantly reduced.

[0044] Example 2: A method for temperature compensation during the rolling process of large TA1 aluminum alloy rings for aerospace use.

[0045] The ring rolling parameters are as follows:

[0046]

[0047] The specific temperature compensation process is as follows:

[0048] (1) A billet with a size of 3200 mm*2400 mm*410 mm was heated to 1320°C and placed on a rolling mill. Before rolling began, an infrared temperature sensor was placed on the outside of the billet to monitor the temperature of the ring in real time during the rolling process.

[0049] (2) During the rolling process, when the ring temperature is monitored to be lower than 1100°C, the feed speed of the core roller begins to decrease, the electromagnetic induction heater starts to work, and temperature compensation of the ring begins.

[0050] (3) During the temperature compensation process, when the ring temperature is detected to be higher than 1320°C, the electromagnetic induction heater stops working, the temperature compensation ends, and the core roller resumes the original feed speed.

[0051] The measurement error of the infrared temperature sensor in step (1) is between ±13.2°C.

[0052] The feed rate in step (2) was reduced to 0.15 mm / s.

[0053] The heating frequency of the electromagnetic heater in step (2) is 100 Hz.

[0054] The heating power of the electromagnetic induction heater in step (2) is 800Kw.

[0055] Through temperature compensation during the rolling process, quality has been significantly improved and defects have been significantly reduced.

Claims

1. A method for temperature compensation during the rolling process of super-large rings for aerospace use, characterized in that: It includes the following steps: (1) Before rolling begins, an infrared temperature sensor is placed on the outside of the ring to monitor the temperature of the ring in real time during the ring rolling process; (2) During the rolling process, when the monitored temperature value is lower than the set minimum rolling temperature, the feed speed of the ring rolling is reduced, and the electromagnetic induction heater surrounding the ring starts to work to compensate the temperature of the ring; (3) When the monitored temperature value is higher than the set maximum rolling temperature, the electromagnetic induction heater stops working, the feed speed of the ring rolling is restored to the original value, and the temperature compensation ends; The ring rolling feed speed in step (2) is reduced to Where R D is the radius of the driving roller, R is the instantaneous outer diameter of the ring, r is the instantaneous inner diameter of the ring, and R M Core roller radius, n D =w D / 2π,w D is the angular velocity; The electromagnetic induction heater described in step (2) moves as the diameter of the ring increases, and the distance between the heating coil of the electromagnetic induction heater and the surface of the ring is fixed.

2. The method for temperature compensation during the rolling process of super-large rings for aerospace use according to claim 1, characterized in that: The infrared temperature sensor in step (1) can output a temperature signal in real time, and its measurement error is between ±1%.

3. The method for temperature compensation during the rolling process of super-large rings for aerospace use according to claim 1 or 2, characterized in that: The temperature signal output by the infrared temperature sensor can be displayed in real time on the monitor.

4. The method for temperature compensation during the rolling process of super-large rings for aerospace use according to claim 1, characterized in that: Heating frequency f of electromagnetic induction heater c =4×10 8 ρ / μa 2 , where ρ is the resistivity of the material in ohms / cm, μ is the relative magnetic permeability of the workpiece, and a is the thickness of the material.

5. The method for temperature compensation during the rolling process of super-large rings for aerospace use according to claim 1, characterized in that: The heating power of the electromagnetic induction heater = (kg / hour production capacity) x (kilowatt-hour / kg) x (efficiency factor), where (kilowatt-hour / kg) is the heat capacity, which refers to the total energy required to heat the material to a specific temperature.

6. A special device for realizing the temperature compensation method in the rolling process of aerospace super-large rings as claimed in claim 1, characterized in that: The invention comprises a horizontally arranged "I"-shaped track (3), an electromagnetic induction heater installed on the "I"-shaped track (3) and capable of freely moving along the track horizontally, and a distance measuring device (7) installed on the electromagnetic induction heater; the electromagnetic induction heater comprises a C-shaped heating coil (4) and a motor and signal processor module (5) installed on the upper part of the C-shaped heating coil (4); the C-shaped heating coil (4) is connected to the motor and signal processor module (5) through a connecting rod; a clamp (6) is provided on the top of the motor and signal processor module (5); the clamp (6) is clamped On the "I"-shaped track (3); a pulley is provided on the fixture (6), which rotates under the drive of a motor, thereby driving the electromagnetic induction heater to move along the "I"-shaped track (3); a distance measuring device (7) is fixed on the inner side of the C-shaped heating coil (4) of the electromagnetic induction heater, and the distance between the distance measuring device (7) and the side surface of the annular workpiece is measured by an infrared probe provided on the distance measuring device (7), and the measured data is transmitted to the motor and signal processor module (5) on the upper part of the coil for controlling the start and stop of the motor, so that the distance between the electromagnetic induction heater and the annular workpiece is kept constant.

7. The dedicated device for the method of temperature compensation during the rolling process of super-large rings for aerospace use according to claim 6, characterized in that: Two ends of the "I"-shaped track (3) are fixed to the first bracket (1) and the second bracket (2), and the first bracket (1) and the second bracket (2) are fixed together with bolts at the connection point with the "I"-shaped track (3).

8. The dedicated device for the method of temperature compensation during the rolling process of super-large rings for aerospace use according to claim 6 is characterized in that: The clamp (6) is a C-shaped structure with an open top, and is used for clamping onto the I-shaped track (3).

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