CN103240275B - On-line heating device and heating method of magnesium alloy sheet warm rolling rollers - Google Patents

Abstract

The invention discloses an online heating device and heating method for warm rolling rolls of magnesium alloy plates. The device is composed of a heating furnace, a positioning device and a temperature control module. The heating furnace is fixed on the rolling mill frame through the positioning device, and the temperature control module detects the heating The internal temperature of the furnace, and real-time regulation and control of heating power; the heating method first seals and preheats the work rolls until the surface temperature reaches the target value, and keeps them warm; then positions the heating device, and simultaneously moves each support roll and work roll to the The position of magnesium alloy during normal warm rolling; trial rolling of magnesium alloy billet to obtain the optimum temperature value; finally start normal rolling, and realize heating at the ideal temperature through feedback control. The present invention does not need to change the structure of the existing roll, and can use a solid roll with high rigidity and strong reliability; adopts the scheme of sealing and preheating first, and then normal heating, so as to realize the rapid heating of the roll; adopts the temperature control strategy of double target temperature, The ideal roll surface temperature is obtained.

Description

On-line heating device and heating method for warm rolling roll of magnesium alloy plate

technical field

The invention belongs to the technical field of plate warm rolling equipment, and in particular relates to an online heating device and a heating method for a magnesium alloy plate warm rolling roll.

Background technique

Magnesium alloy is a modern lightweight structural metal material with the characteristics of low density, high specific strength and specific stiffness, as well as excellent electromagnetic shielding, damping and shock absorption and machinability. It is widely used in aerospace, automotive and electronic products, etc. The field has broad application prospects. China is a country rich in magnesium resources, its reserves and export volume of primary magnesium both rank first in the world, but the production technology of magnesium alloy plates and profiles with high added value is backward. At present, most magnesium alloy products are formed by casting, especially die-casting process, and the rolling technology of deformed magnesium alloy sheet is not yet mature, which limits the application range of magnesium alloy.

One of the difficulties in the warm rolling technology of magnesium alloy sheets is that the rolling temperature range is narrow. If the temperature of the roll surface cannot be maintained, the magnesium sheet will be cooled rapidly and the plasticity will deteriorate, resulting in more surface cracks and edge cracks on the rolled workpiece. Unable to obtain ideal tissue and mechanical properties. Therefore, the rolls are generally heated before and during rolling.

An existing method is to use a combustion heat source to directly heat the surface of the roll, remove the heat source after reaching the target temperature, and then carry out rolling. Due to the continuous heat dissipation of the rolls, the contact temperature difference between different billets and rolls, or even between different positions of the same billet and the rolls, is different, and the uniformity of the rolled plate is affected; , reheating the roll, the rolling efficiency is low.

Chinese patents CN1745920A and CN101249512A respectively disclose a roll core heating device for a magnesium alloy plate roll, both of which adopt a built-in heating rod in the roll core and a temperature control box outside the roll to maintain the surface temperature of the roll during rolling. Since the rigidity of the hollow roll is lower than that of the solid roll, the sand holes and pores on the surface of the inner hole of the roll are easy to induce stress concentration under the action of the down pressure, and the reliability is poor; and the size of the inner hole of the roll is limited, and the heating efficiency is not high.

Chinese patent CN202238896U discloses a roll preheating device, which is characterized in that the resistance wire around the roll is divided into several sections in the axial direction, and several thermometers are used to detect the temperature of the surface of each section of the roll. However, it is necessary to change the roll after heating with this device, and the work efficiency is not high; and since the temperature of the roll surface cannot be controlled during the rolling process, it is difficult to guarantee the quality of the product.

Contents of the invention

The purpose of the present invention is to provide an on-line heating device and heating method for warm rolling rolls of magnesium alloy sheets, which can ensure the temperature of the roll surface during the rolling process without changing the structure of the existing rolls and without changing the rolls, so as to obtain excellent Microstructure and Mechanical Properties of Magnesium Alloy Rolled Sheets. The present invention is applicable to two-roll and multi-roll warm rolling mills for magnesium alloy plates. The following is an example of a four-roll rolling mill. The four-roll mill includes two support rolls and two work rolls. The heating of the work rolls is divided into preheating and normal heating. Two stages of heating.

In order to solve the problems of the technologies described above, the present invention is realized through the following technical solutions:

An online heating device for warm rolling rolls of magnesium alloy plates, mainly composed of a heating furnace 1, a positioning device 2 and a temperature control module 3, the heating furnace 1 is fixed on the rolling mill frame through the positioning device 2, and the temperature control module 3 detects The internal temperature of the heating furnace 1, and real-time control of the heating power;

The heating furnace main body 10 in the heating furnace 1 is fixed on the heating furnace fixed plate 20, and the heating furnace fixed plate 20 is fixed on the rolling mill frame. The upper sliding cover lifting rod 22 and the lower sliding cover lifting rod 23 are respectively fixedly connected with the corresponding sliders and embedded in the chute 212 of the lifting rod rotating disk 21, the upper sliding cover 11 of the heating furnace and the lower heating furnace sliding cover The surface of 12 is equipped with bearings, which are fixedly connected with the upper sliding cover elevating rod 22 and the lower sliding cover elevating rod 23 respectively; the end heat shield 13 in the heating furnace 1 has a through hole for laying the thermocouple channel 38. Both sides of the work roll 42 are respectively equipped with a thermocouple 36 at the inlet side of the sheet and a thermocouple 37 at the outlet side of the sheet metal, and are connected to the temperature control unit 30 together with the heating element 34 at the inlet side of the sheet material and the heating element 35 at the outlet side of the sheet material. The structure of the heating device of the lower work roll 43 is the same.

The heating furnace 1 is composed of a heating furnace main body 10, a heating furnace upper sliding cover 11, a heating furnace sliding cover 12 and an end heat shield 13, which are sealed as a whole, wherein the heating furnace main body 10, the heating furnace upper sliding cover 11 and the heating furnace sliding cover 12 are in the form of "furnace shell-insulation layer-furnace lining" from the outside to the inside.

In the preheating stage, a certain distance is reserved between every two adjacent rolls in the four rolls, and the upper work roll 42 can be preheated in the closed space formed by the heating furnace 1 , the upper work roll 42 keeps rotating at a low and constant speed during the preheating process. Heating in a closed space can improve heating efficiency, and uniform rotation can make the upper work roll 42 evenly heated. The same applies to the lower work roll 43 .

Fig. 2 is the overall schematic diagram of the roll and the heating device in the normal heating stage. The main body 10 of the heating furnace, the end heat shield 13, the fixed plate 20 of the heating furnace and the rotating plate 21 of the lifting rod are all left and right split structures. When the device is working, the symmetrical structures on the left and right sides are combined, so the heating device is not interfered by the bearings at both ends of the roll, and it is convenient to directly seal and heat the installed roll. At the same time, the left and right split furnace structure It is convenient to overhaul the failed parts in the heating furnace 1 and the temperature control module 3 .

In the warm rolling stage of the magnesium alloy plate, the upper sliding cover lifting rod 22 and the lower sliding cover lifting rod 23 rotate to the other end of the respective chute on the lifting rod rotating disk 21, and the upper sliding cover 11 of the heating furnace and the lower heating furnace Slide cover 12 moves to the middle part of heating furnace main body 10, reserves space for rolling equipment normal work and plate movement. The same applies to the lower work roll 43 .

Fig. 3 is a structural diagram of the heating device in the normal heating stage. As shown in Fig. 3(a), the main body 10 of the heating furnace is equipped with a sheet material inlet side thermocouple 36 and a sheet material outlet side thermocouple 37, and the plate The thermocouple 36 at the material inlet side is used to detect the temperature of the surface of the upper work roll 42 that will be in contact with the sheet material 44. If the temperature value is inconsistent with the ideal value, the temperature control unit 30 adjusts the temperature of the sheet material through the pressure regulating mechanism 32 at the sheet material inlet side. The output voltage of the heating element 34 on the inlet side until the temperature fed back by the thermocouple 36 on the inlet side of the plate reaches the ideal temperature required by the roll surface. Since the surface of the upper work roll 42 is exposed to the air when it rotates directly above, and is in contact with the upper support roll 40, the temperature changes drastically at this time, and the heating time of the heating element 34 on the sheet inlet side is limited, only by adjusting the sheet inlet The voltage at both ends of the side heating element 34 may cause adjustment lag, resulting in an unsatisfactory temperature on the surface of the work roll that is just in contact with the sheet material. The temperature of the surface in contact, and cooperate with the temperature control unit 30, the pressure regulating mechanism 33 on the outlet side of the sheet metal and the heating element 35 on the outlet side of the sheet metal to adjust the temperature of the surface in this area. The corresponding temperature control principle is shown in Figure 3(b) Show. Because the heat dissipation of the surface that is about to be in contact with the upper support roller 40 is constant, there must be an optimum temperature, so that the surface of this area can be heated by the heat dissipation and the initial voltage of the heating element 34 on the entry side of the sheet to achieve the same temperature as the sheet. At the ideal temperature at contact, the voltage across the heating element 34 on the entry side of the sheet requires minimal adjustment and the corresponding adjustment hysteresis is minimized. The optimum temperature value of the surface to be in contact with the upper backup roll 40 can be obtained by experimentation. The adjustment of the surface temperature of the lower work roll 43 is the same.

The pressure regulating mechanism 32 on the sheet material inlet side is composed of an executive motor, a reducer and a pressure regulator;

Figure 3(c) is a front view of the heating device at the sheet material inlet side during the normal heating stage. Since the left and right ends of the work roll and the thermocouple channel 37 communicate with the outside world, a certain amount of heat loss will be caused, so the work rolls at both ends and in the middle The surface is in different temperature fields. In order to achieve precise temperature control, the temperature control area is divided into three sections: left, middle and right, and heating elements and thermocouples are set respectively. The layout of the heating device on the outlet side is the same.

Fig. 4 is the schematic diagram of locating device, and described upper sliding cover lifting rod 22 is made up of hydraulic cylinder 220, lifting rod 221, connecting arm 222 and bearing 223, and one end of connecting arm 222 is welded on the lifting rod 221, and the other end is connected with the lifting rod 221. The support 223 is connected by bolts, and the support 223 is connected with the upper sliding cover 11 of the heating furnace. The upper sliding cover lifting rod 22 moves circularly on the lifting rod rotating disk 21 through the slide block 211, and after reaching the end of the chute 212, it is fixed by the pin 213.

FIG. 5 is a schematic diagram of the end heat shield 13, the interior of the end heat shield 13 is filled with heat insulation cotton, and has a through hole through which the thermocouple channel 38 passes.

A method for on-line heating of a magnesium alloy plate warm rolling roll, comprising the following steps:

1) Seal and preheat the work roll until the surface temperature reaches the target value and keep it warm;

2) Position the heating device, and at the same time move each backup roll and work roll to the position of the normal warm rolling of the magnesium alloy;

3) Trial rolling of the magnesium alloy billet to obtain the best temperature value;

4) Start normal rolling, and realize heating at ideal temperature through feedback control.

Specifically, each step is completed in the following ways:

1) Move the four rolls separately so that there is a certain distance between every two adjacent rolls, and seal the main body 10 of the heating furnace, the upper sliding cover 11 of the heating furnace, the lower cover 12 of the heating furnace and the end heat shield 13 As a whole, the upper work roll 42 is sealed and preheated until the temperature of the left, middle and right surfaces of the upper work roll 42 fed back by the thermocouple 36 at the sheet material inlet side and the thermocouple 37 at the sheet material outlet side all reach the target value, And keep warm for 30-40 minutes, the preheating of lower work roll 43 is the same;

2) Move the upper sliding cover 11 of the heating furnace and the lower sliding cover 12 of the heating furnace to the middle of the main body 10 of the heating furnace to leave space for the normal operation of the rolling equipment and the movement of the sheet metal, and position the heating device of the lower work roll 43 in the same way, At the same time, the upper back-up roll 40, the lower back-up roll 41, the upper work roll 42 and the lower work roll 43 are moved to the position during normal warm rolling of the magnesium alloy;

3) Carry out trial rolling of the magnesium alloy blank. During this process, the temperature value detected by the thermocouple 36 on the inlet side of the sheet is only displayed and not used for feedback adjustment. The temperature value detected by the thermocouple 37 on the outlet side of the sheet is both It is displayed and used for feedback adjustment, keeping the voltage at both ends of the heating element 34 on the sheet material inlet side unchanged, setting the initial target temperature for the surface that will be in contact with the upper support roller 40, and the temperature control unit 30 adjusts the heating element 35 on the sheet material outlet side The voltage at both ends makes the temperature on the surface of the area finally stabilized at the initial target value, and record the temperature detected by the thermocouple 36 at the sheet inlet side at this time. Within the acceptable range, then the target temperature of the surface that will be in contact with the upper support roller 40 at this time is the optimum temperature value, otherwise change the target temperature of the surface in this area until finding the optimum temperature value that meets the above requirements, Lower support roller 41 is the same;

4) Start normal rolling, the temperature values detected by the thermocouple 36 on the sheet inlet side and the thermocouple 37 on the sheet outlet side are both displayed and used for feedback adjustment. The temperature control unit 30 adjusts the heating element on the sheet outlet side in real time 35, so that the temperature of the surface that is about to be in contact with the upper support roll 40 reaches an optimal value, and then by real-time adjustment of the voltage at both ends of the heating element 34 on the sheet material inlet side, the surface of the upper work roll 42 that is about to be in contact with the sheet is finally obtained ideal temperature.

The advantages and beneficial effects of the present invention are: it is not necessary to change the structure of the existing roll, and a solid roll with high rigidity and strong reliability can be used; the scheme of sealing and preheating first and then normal heating is adopted to realize the rapid heating of the roll; The temperature control strategy of the target temperature obtains the ideal roll surface temperature. It can be seen that the present invention has high working efficiency, high degree of automation, precise temperature control and good application prospect.

Description of drawings

Figure 1 is a schematic diagram of a single work roll heating device in the preheating stage

Figure 2 is the overall schematic diagram of the roll and heating device in the normal heating stage

Figure 3 is a structural diagram of the heating device in the normal heating stage

Among them, Figure 3(a) is a cross-sectional view of the entire heating device in the normal heating stage

Figure 3(b) Schematic diagram of temperature control of the temperature control module

Figure 3(c) is the front view of the heating device at the inlet side of the sheet during the normal heating stage

Figure 4 is a schematic diagram of the positioning device

Figure 5 is a schematic diagram of the end heat shield

In the picture:

1. Heating furnace 2. Positioning device 3. Temperature control module

10. The main body of the heating furnace 11. The upper sliding cover of the heating furnace 12. The sliding cover of the heating furnace 13. The end heat shield

20. Heating furnace fixed plate

21. Lifting rod rotating disc 210, rotating disc main body 211, slider 212, chute 213, pin

22. Upper sliding cover lifting rod 220, hydraulic cylinder 221, lifting rod 222, connecting arm 223, support 224, bolts

23. Lifting lever for sliding cover

30. Temperature control unit 31. AC power supply 32. Sheet metal inlet side pressure regulating mechanism 33. Sheet metal outlet side pressure regulating mechanism

34. Heating element on the sheet inlet side 35. Heating element on the sheet outlet side 36. Thermocouple on the sheet inlet side

37. Thermocouple on sheet metal outlet side 38. Thermocouple channel

40. Upper support roll 41. Lower support roll 42. Upper work roll 43. Lower work roll 44. Sheet

45. In/out chute

Detailed ways

The present invention will be further described below in conjunction with the accompanying drawings.

1 and 3, an on-line heating device for warm rolling rolls of magnesium alloy sheets according to the present invention is mainly composed of a heating furnace 1, a positioning device 2 and a temperature control module 3, and the heating furnace 1 is fixed on the On the rolling mill stand, the temperature control module 3 detects the internal temperature of the heating furnace 1, and regulates the heating power in real time;

The heating furnace main body 10 in the heating furnace 1 is fixed on the heating furnace fixed plate 20, and the heating furnace fixed plate 20 is fixed on the rolling mill frame. The upper sliding cover lifting rod 22 and the lower sliding cover lifting rod 23 are respectively fixedly connected with the corresponding sliders and embedded in the chute 212 of the lifting rod rotating disk 21, the upper sliding cover 11 of the heating furnace and the lower heating furnace sliding cover The surface of 12 is equipped with bearings, which are fixedly connected with the upper sliding cover elevating rod 22 and the lower sliding cover elevating rod 23 respectively; the end heat shield 13 in the heating furnace 1 has a through hole for laying the thermocouple channel 38. Both sides of the work roll 42 are respectively equipped with a thermocouple 36 at the inlet side of the sheet and a thermocouple 37 at the outlet side of the sheet metal, and are connected to the temperature control unit 30 together with the heating element 34 at the inlet side of the sheet material and the heating element 35 at the outlet side of the sheet material. The structure of the heating device of the lower work roll 43 is the same.

The heating furnace 1 is composed of a heating furnace main body 10, a heating furnace upper sliding cover 11, a heating furnace sliding cover 12 and an end heat shield 13, which are sealed as a whole, wherein the heating furnace main body 10, the heating furnace upper sliding cover 11 and the heating furnace sliding cover 12 are in the form of "furnace shell-insulation layer-furnace lining" from the outside to the inside.

In the preheating stage, a certain distance is reserved between every two adjacent rolls in the four rolls, and the upper work roll 42 can be preheated in the closed space formed by the heating furnace 1 , the upper work roll 42 keeps rotating at a low and constant speed during the preheating process. Heating in a closed space can improve heating efficiency, and uniform rotation can make the upper work roll 42 evenly heated. The same applies to the lower work roll 43 .

Fig. 2 is the overall schematic diagram of the roll and the heating device in the normal heating stage. The main body 10 of the heating furnace, the end heat shield 13, the fixed plate 20 of the heating furnace and the rotating plate 21 of the lifting rod are all left and right split structures. When the device is working, the symmetrical structures on the left and right sides are combined, so the heating device is not interfered by the bearings at both ends of the roll, and it is convenient to directly seal and heat the installed roll. At the same time, the left and right split furnace structure It is convenient to overhaul the failed parts in the heating furnace 1 and the temperature control module 3 .

In the warm rolling stage of the magnesium alloy plate, the upper sliding cover lifting rod 22 and the lower sliding cover lifting rod 23 rotate to the other end of the respective chute on the lifting rod rotating disk 21, and the upper sliding cover 11 of the heating furnace and the lower heating furnace Slide cover 12 moves to the middle part of heating furnace main body 10, reserves space for rolling equipment normal work and plate movement. The same applies to the lower work roll 43 .

Fig. 3 is a structural diagram of the heating device in the normal heating stage. As shown in Fig. 3(a), the main body 10 of the heating furnace is equipped with a sheet material inlet side thermocouple 36 and a sheet material outlet side thermocouple 37, and the plate The thermocouple 36 at the material inlet side is used to detect the temperature of the surface of the upper work roll 42 that will be in contact with the sheet material 44. If the temperature value is inconsistent with the ideal value, the temperature control unit 30 adjusts the temperature of the sheet material through the pressure regulating mechanism 32 at the sheet material inlet side. The output voltage of the heating element 34 on the inlet side until the temperature fed back by the thermocouple 36 on the inlet side of the plate reaches the ideal temperature required by the roll surface. Since the surface of the upper work roll 42 is exposed to the air when it rotates directly above, and is in contact with the upper support roll 40, the temperature changes drastically at this time, and the heating time of the heating element 34 on the sheet inlet side is limited, only by adjusting the sheet inlet The voltage at both ends of the side heating element 34 may cause adjustment lag, resulting in an unsatisfactory temperature on the surface of the work roll that is just in contact with the sheet material. The temperature of the surface in contact, and cooperate with the temperature control unit 30, the pressure regulating mechanism 33 on the outlet side of the sheet metal and the heating element 35 on the outlet side of the sheet metal to adjust the temperature of the surface in this area. The corresponding temperature control principle is shown in Figure 3(b) Show. Because the heat dissipation of the surface that is about to be in contact with the upper support roller 40 is constant, there must be an optimum temperature, so that the surface of this area can be heated by the heat dissipation and the initial voltage of the heating element 34 on the entry side of the sheet to achieve the same temperature as the sheet. At the ideal temperature at contact, the voltage across the heating element 34 on the entry side of the sheet requires minimal adjustment and the corresponding adjustment hysteresis is minimized. The optimum temperature value of the surface to be in contact with the upper backup roll 40 can be obtained by experimentation. The adjustment of the surface temperature of the lower work roll 43 is the same.

The pressure regulating mechanism 32 on the sheet material inlet side is composed of an executive motor, a reducer and a pressure regulator;

Figure 3(c) is a front view of the heating device at the sheet material inlet side during the normal heating stage. Since the left and right ends of the work roll and the thermocouple channel 37 communicate with the outside world, a certain amount of heat loss will be caused, so the work rolls at both ends and in the middle The surface is in different temperature fields. In order to achieve precise temperature control, the temperature control area is divided into three sections: left, middle and right, and heating elements and thermocouples are set respectively. The layout of the heating device on the outlet side is the same.

Fig. 4 is the schematic diagram of locating device, and described upper sliding cover lifting rod 22 is made up of hydraulic cylinder 220, lifting rod 221, connecting arm 222 and bearing 223, and one end of connecting arm 222 is welded on the lifting rod 221, and the other end is connected with the lifting rod 221. The support 223 is connected by bolts, and the support 223 is connected with the upper sliding cover 11 of the heating furnace. The upper sliding cover lifting rod 22 moves circularly on the lifting rod rotating disk 21 through the slide block 211, and after reaching the end of the chute 212, it is fixed by the pin 213.

FIG. 5 is a schematic diagram of the end heat shield 13, the interior of the end heat shield 13 is filled with heat insulation cotton, and has a through hole through which the thermocouple channel 38 passes.

A method for on-line heating of a magnesium alloy plate warm rolling roll, comprising the following steps:

1) Seal and preheat the work roll until the surface temperature reaches the target value and keep it warm;

2) Position the heating device, and at the same time move each backup roll and work roll to the position of the normal warm rolling of the magnesium alloy;

3) Trial rolling of the magnesium alloy billet to obtain the best temperature value;

4) Start normal rolling, and realize heating at ideal temperature through feedback control.

Specifically, each step is specifically completed through the following methods:

1) Move the four rolls separately so that there is a certain distance between every two adjacent rolls, and seal the main body 10 of the heating furnace, the upper sliding cover 11 of the heating furnace, the lower cover 12 of the heating furnace and the end heat shield 13 As a whole, the upper work roll 42 is sealed and preheated until the temperature of the left, middle and right surfaces of the upper work roll 42 fed back by the thermocouple 36 at the sheet material inlet side and the thermocouple 37 at the sheet material outlet side all reach the target value, And keep warm for 30-40 minutes, the preheating of lower work roll 43 is the same;

2) Move the upper sliding cover 11 of the heating furnace and the lower sliding cover 12 of the heating furnace to the middle of the main body 10 of the heating furnace to leave space for the normal operation of the rolling equipment and the movement of the sheet metal, and position the heating device of the lower work roll 43 in the same way, At the same time, the upper back-up roll 40, the lower back-up roll 41, the upper work roll 42 and the lower work roll 43 are moved to the position during normal warm rolling of the magnesium alloy;

3) Carry out trial rolling of the magnesium alloy blank. During this process, the temperature value detected by the thermocouple 36 on the inlet side of the sheet is only displayed and not used for feedback adjustment. The temperature value detected by the thermocouple 37 on the outlet side of the sheet is both It is displayed and used for feedback adjustment, keeping the voltage at both ends of the heating element 34 on the sheet material inlet side unchanged, setting the initial target temperature for the surface that will be in contact with the upper support roller 40, and the temperature control unit 30 adjusts the heating element 35 on the sheet material outlet side The voltage at both ends makes the temperature on the surface of the area finally stabilized at the initial target value, and record the temperature detected by the thermocouple 36 at the sheet inlet side at this time. Within the acceptable range, then the target temperature of the surface that will be in contact with the upper support roller 40 at this time is the optimum temperature value, otherwise change the target temperature of the surface in this area until finding the optimum temperature value that meets the above requirements, Lower support roller 41 is the same;

4) Start normal rolling, the temperature values detected by the thermocouple 36 on the sheet inlet side and the thermocouple 37 on the sheet outlet side are both displayed and used for feedback adjustment. The temperature control unit 30 adjusts the heating element on the sheet outlet side in real time 35, so that the temperature of the surface that is about to be in contact with the upper support roll 40 reaches an optimal value, and then by real-time adjustment of the voltage at both ends of the heating element 34 on the sheet material inlet side, the surface of the upper work roll 42 that is about to be in contact with the sheet is finally obtained ideal temperature.

It is worth pointing out that the manner given here is only used as a specific implementation manner of the present invention, and obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all the embodiments.

The present invention is applicable to two-roll and multi-roll magnesium alloy plate warm rolling mills. The above only takes four-roll rolling mill as an example for introduction. It is easy to see that other multi-roll magnesium alloy plate warm rolling mills can be realized by analogy.

Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without creative efforts fall within the protection scope of the present invention.

Claims (6)

1. An online heating device for warm rolling rolls of magnesium alloy sheets, consisting of a heating furnace (1), a positioning device (2) and a temperature control module (3), the heating furnace (1) is fixed by the positioning device (2) On the rolling mill stand, the temperature control module (3) detects the internal temperature of the heating furnace (1), and regulates the heating power in real time; it is characterized in that: The heating furnace main body (10) in the heating furnace (1) is fixed on the heating furnace fixed plate (20), the heating furnace fixed plate (20) is fixed on the rolling mill stand, and the lifting rod in the positioning device (2) The rotating disc (21) is fixedly connected with the fixed disc (20) of the heating furnace, and the upper sliding cover lifting rod (22) and the lower sliding cover lifting rod (23) are respectively fixedly connected with the corresponding sliders and embedded in the lifting rod rotating disc ( In the chute (212) of 21), supports are installed on the surfaces of the upper sliding cover (11) of the heating furnace and the sliding cover (12) of the heating furnace. (23) Fixed connection; the end heat shield (13) in the heating furnace (1) has a through hole for laying the thermocouple channel (38), and plates are installed on the two sides of the upper work roll (42) respectively. The thermocouple (36) on the material inlet side and the thermocouple (37) on the material outlet side are connected to the temperature control unit (30) together with the heating element (34) on the material inlet side and the heating element (35) on the material outlet side; The structure of the heating device of the roller (43) is the same; The heating furnace (1) is composed of a heating furnace main body (10), a heating furnace upper sliding cover (11), a heating furnace sliding cover (12) and an end heat shield (13), which are sealed as a whole, wherein The main body of the heating furnace (10), the upper sliding cover of the heating furnace (11) and the lower sliding cover of the heating furnace (12) are all in the form of "furnace shell-insulation layer-furnace lining" from outside to inside; The main body (10) of the heating furnace, the end heat shield (13), the fixed plate of the heating furnace (20) and the rotating plate of the lifting rod (21) are all left and right split structures. When the heating device is working, the left and right sides The symmetrical structures of the sides are combined; In the preheating stage, a certain distance is reserved between every two adjacent rolls among the four rolls, and the upper work roll (42) is realized in the closed space formed by the heating furnace (1). Preheating, during the preheating process, the upper work roll (42) keeps rotating at a low and constant speed; In the warm rolling stage of the magnesium alloy sheet, the upper sliding cover lifting rod (22) and the lower sliding cover lifting rod (23) rotate to the other end of the respective chute on the lifting rod rotating disk (21), and the heating furnace slides The cover (11) and the sliding cover (12) of the heating furnace are moved to the middle of the main body (10) of the heating furnace to leave space for the normal operation of the rolling equipment and the movement of the sheet metal; the same is true for the lower work roll (43); In the normal heating stage, the temperature control area of the heating device on the inlet side is divided into three sections: left, middle and right, where heating elements and thermocouples are installed respectively; the layout of the heating device on the outlet side is the same. 2. The online heating device for warm rolling rolls of a magnesium alloy plate according to claim 1, characterized in that: The main body (10) of the heating furnace is equipped with a sheet metal inlet side thermocouple (36) and a sheet material outlet side thermocouple (37), and the sheet material inlet side thermocouple (36) detects the upper work roll (42 ) the temperature of the surface that will be in contact with the sheet material (44). When the temperature value is inconsistent with the ideal value, the temperature control unit (30) adjusts the heating element ( 34) until the temperature fed back by the thermocouple (36) at the sheet inlet side reaches the ideal temperature required by the roll surface; The thermocouple (37) on the sheet material outlet side detects the temperature of the surface that is about to be in contact with the upper support roller (40), and communicates with the temperature control unit (30), the sheet material outlet side pressure regulating mechanism (33) and the sheet material outlet The side heating elements (35) cooperate to regulate the temperature of the surface in this area; the same is true for the regulation of the surface temperature of the lower work roll (43). 3. The online heating device for warm rolling rolls of a magnesium alloy plate according to claim 2, characterized in that: The pressure regulating mechanism (32) at the sheet material inlet side is composed of an executive motor, a reducer and a pressure regulator. 4. The on-line heating device for warm rolling rolls of magnesium alloy sheets according to any one of claims 1 to 3, characterized in that: The upper sliding cover lifting rod (22) is composed of a hydraulic cylinder (220), a lifting rod (221), a connecting arm (222) and a support (223), and one end of the connecting arm (222) is fixed on the lifting rod (221 ), the other end is fixedly connected with the support (223), and the support (223) is connected with the upper sliding cover (11) of the heating furnace; The upper sliding cover lifting rod (22) makes a circular motion on the lifting rod rotating disk (21) through the slider (211), and after reaching the end of the chute (212), it is fixed by a pin (213) . 5. An online heating device for warm rolling rolls of magnesium alloy sheets according to any one of claims 1 to 3, characterized in that: The inside of the end heat shield (13) is filled with heat insulation cotton. 6. A method for on-line heating of a magnesium alloy plate warm rolling roll, comprising the following steps: 1) Seal and preheat the work roll until the surface temperature reaches the target value and keep it warm; 2) Position the heating device, and at the same time move each backup roll and work roll to the position of the normal warm rolling of the magnesium alloy; 3) Trial rolling of the magnesium alloy billet to obtain the best temperature value; 4) Start normal rolling, and realize heating at ideal temperature through feedback control. Specifically through the following methods: 1) Move the four rolls separately so that there is a certain distance between every two adjacent rolls, and put the heating furnace main body (10), heating furnace upper sliding cover (11), heating furnace sliding cover (12) and end The upper heat shield (13) is sealed as a whole, and the upper work roll (42) is sealed and preheated until the upper work roll ( 42) The temperatures of the left, middle and right surfaces all reach the target value, and keep warm for 30 to 40 minutes, and the preheating of the lower work roll (43) is the same; 2) Move the upper sliding cover (11) and the lower sliding cover (12) of the heating furnace to the middle of the main body (10) of the heating furnace to leave space for the normal operation of the rolling equipment and the movement of the sheet metal, and work under the same positioning The heating device for the roll (43) moves the upper back-up roll (40), the lower back-up roll (41), the upper work roll (42) and the lower work roll (43) to the position of the normal warm rolling of the magnesium alloy at the same time; 3) Carry out trial rolling of the magnesium alloy billet. During this process, the temperature value detected by the thermocouple (36) on the inlet side of the sheet is only displayed and not used for feedback adjustment, and the temperature value detected by the thermocouple (37) on the outlet side of the sheet is obtained The temperature value is both displayed and used for feedback adjustment. Keep the voltage at both ends of the heating element (34) on the sheet inlet side constant, and set the initial target temperature for the surface that will be in contact with the upper support roller (40). The temperature control unit ( 30) Adjust the voltage at both ends of the heating element (35) on the sheet metal outlet side so that the temperature of the surface of the magnesium alloy billet that is about to be in contact with the upper support roller (40) is finally stabilized at the initial target value, and record the thermocouple (36 ) detected temperature, when the temperature value reaches the ideal temperature of the surface of the work roll that will be in contact with the sheet or is within an acceptable range, then the target of the surface that will be in contact with the upper support roll (40) at this time The temperature is the optimal temperature value, otherwise change the target temperature of the surface of the magnesium alloy billet that will be in contact with the upper support roll (40) until the optimum temperature value that meets the above requirements is found, and the same is true for the lower support roll (41); 4) Start normal rolling, the temperature values detected by the thermocouple (36) on the inlet side of the sheet and the thermocouple (37) on the outlet side of the sheet are both displayed and used for feedback adjustment, and the temperature control unit (30) adjusts in real time The voltage at both ends of the heating element (35) on the sheet material exit side makes the temperature of the surface that will be in contact with the upper support roller (40) reach the optimum value, and then adjust the voltage at both ends of the sheet material inlet side heating element (34) in real time, and finally Obtain the ideal temperature for the surface of the upper work roll (42) that will be in contact with the sheet.

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