Curled titanium belt temperature control method

Abstract

The invention provides a temperature control method for a curled titanium belt, and belongs to the technical field of hot rolling method control. Comprising the following steps that the target temperature of a titanium belt is obtained; after the titanium strip is discharged from the finishing mill, a finish rolling real-time temperature curve of the titanium strip is obtained through a pyrometer arranged at an outlet of the finishing mill; according to the difference value between the titanium belt head finish rolling real-time temperature and the finish rolling target temperature, the head avoiding length of the belt head of the titanium belt and the tail avoiding length of the belt tail of the titanium belt are determined; a cooling header is started to cool the titanium belt; after the recoiling machine detects that the titanium belt arrives, the real-time crimping temperature is obtained through a pyrometer arranged in front of the crimping machine, and the water pressure of belt pressing water started in front of the crimping machine is determined according to the difference value between the real-time crimping temperature and the target crimping temperature. Through high-temperature rolling, stress concentration in the deformation process is relieved; laminar cooling control in a continuous rolling unit is used for increasing the cooling speed after rolling, and the problems of coarse grains, uneven structures and the like are solved.

Description

Technical Field

[0001] The invention relates to the technical field of hot rolling methods, and in particular to a temperature control method for a curled titanium strip. Background Art

[0002] Titanium has excellent properties such as light weight, high specific strength, corrosion resistance, and high temperature resistance. It has been widely used in aerospace, national defense and military industries. However, titanium is a typical close-packed hexagonal metal structure, and its mechanical properties have significant anisotropy, which seriously restricts its plastic processing. The use of high-temperature rolling in hot rolling production can enhance the mobility of atoms, and more slip systems can be activated. Their activation helps to coordinate the plastic deformation of close-packed hexagonal metals, greatly reducing the critical shear stress of non-basal slip in close-packed hexagonal metals, and reducing stress concentration during deformation. However, if the cooling process after high-temperature rolling is too long, it will cause coarse grains and uneven cooling of the internal structure, which will make it more likely to have brittle fractures in subsequent practical applications, and performance fluctuations in areas of stress concentration.

[0003] Therefore, in order to solve the above problems, it is particularly important to develop a method for rapid cooling after high temperature rolling. Summary of the invention

[0004] According to the above proposal, if the cooling process time is too long, it will cause coarse grains and uneven cooling of the internal structure, and a method for controlling the temperature of a curled titanium strip is provided.

[0005] The technical means adopted by the present invention are as follows:

[0006] A method for controlling the temperature of a coiled titanium strip, wherein the titanium strip is heated to a temperature of 890 to 950° C. by a heating furnace, and the temperature of the titanium strip at a finishing entrance is controlled to be 800 to 850° C. by a rough rolling process; the method comprises the following steps:

[0007] S1: obtaining the target temperature of the titanium strip;

[0008] S2: After the titanium strip leaves the finishing mill, the final rolling real-time temperature curve of the titanium strip is obtained through a pyrometer set at the exit of the finishing mill;

[0009] S3: determining the head allowance length L of the titanium strip head and the tail allowance length L of the titanium strip tail according to the difference T1 between the final rolling real-time temperature of the titanium strip head and the final rolling target temperature;

[0010] S4: Open the cooling header to cool the titanium strip;

[0011] S5: After the coiler detects the arrival of the titanium strip, the real-time coiling temperature is obtained through the pyrometer installed in front of the coiler. According to the difference T2 between the real-time coiling temperature and the target coiling temperature, the water pressure P of the strip pressing water opened in front of the coiler is determined.

[0012] Furthermore, in S1, the target temperature includes: a finishing rolling target temperature and a curling target temperature.

[0013] Furthermore, in S1, the target temperature is determined in advance according to the process; the final rolling target temperature is 740-780°C; and the curling target temperature is 480-530°C.

[0014] Furthermore, in S2, a first pyrometer and a second pyrometer are provided at the finishing exit; the temperature collection ranges of the first pyrometer and the second pyrometer are both 300-1100°C.

[0015] Furthermore, in S2, the higher temperature of the first pyrometer and the second pyrometer is selected as the input value of the final rolling real-time temperature curve of the titanium strip.

[0016] Furthermore, the final rolling real-time temperature is the average value of the final rolling real-time temperature measured 0.1S after the start.

[0017] Further, in S3, the relationship between the head allowance length L of the titanium strip head and the tail allowance length L of the titanium strip tail and the difference T1 between the final rolling real-time temperature of the titanium strip head and the final rolling target temperature is:

[0018] T1≤10℃, L=10m;

[0019] 10℃<T1≤20℃, L=8m;

[0020] 20℃<T1≤50℃, L=5m.

[0021] Furthermore, a third pyrometer and a fourth pyrometer are arranged in front of the coiler; the temperature collection ranges of the third pyrometer and the fourth pyrometer are both 300-1100°C.

[0022] Furthermore, the real-time curling temperature is an average value of the real-time curling temperature measured 0.1S after the start.

[0023] Furthermore, the difference T2 between the actual curling temperature and the target curling temperature and the water pressure P of the belt water that needs to be turned on in front of the crimping machine are related to:

[0024] T2<0℃, P=0-2bar, close the cooling header water in advance;

[0025] 0℃<T2≤10℃, P=3~6bar;

[0026] 10℃<T2≤20℃, P=6~8bar;

[0027] 20℃<T2≤50℃, P=8~10bar.

[0028] Compared with the prior art, the present invention has the following advantages:

[0029] The present invention reduces stress concentration during deformation by high-temperature rolling, and uses laminar cooling control in the continuous rolling mill to increase cooling speed after rolling, improve problems such as coarse grains and uneven structure, greatly improves product quality, reduces costs, and has good economic benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0030] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative labor.

[0031] Figure 1 It is a schematic diagram of the overall process of the present invention. DETAILED DESCRIPTION

[0032] It should be noted that, in the absence of conflict, the embodiments of the present invention and the features in the embodiments can be combined with each other. The present invention will be described in detail below with reference to the accompanying drawings and in combination with the embodiments.

[0033] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is by no means intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0034] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprising" and / or "including" are used in this specification, it indicates the presence of features, steps, operations, devices, components and / or combinations thereof.

[0035] Unless otherwise specifically stated, the relative arrangement, numerical expressions and numerical values ​​of the parts and steps described in these embodiments do not limit the scope of the present invention. At the same time, it should be clear that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The technology, methods and equipment known to ordinary technicians in the relevant field may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be regarded as a part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary, rather than as a limitation. Therefore, other examples of exemplary embodiments may have different values. It should be noted that similar reference numerals and letters represent similar items in the following drawings, so once a certain item is defined in an accompanying drawing, it does not need to be further discussed in subsequent drawings.

[0036] In the description of the present invention, it is necessary to understand that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "lateral, vertical, perpendicular, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention: the directional words "inside and outside" refer to the inside and outside relative to the contours of each component itself.

[0037] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used here to describe the spatial positional relationship between a device or feature and other devices or features as shown in the figure. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figure. For example, if the device in the accompanying drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below their position devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0038] In addition, it should be noted that the use of terms such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. If not otherwise stated, the above terms have no special meaning and therefore cannot be understood as limiting the scope of protection of the present invention.

[0039] A method for controlling the temperature of a coiled titanium strip, wherein the titanium strip is heated to a temperature of 890 to 950° C. by a heating furnace, and the temperature of the titanium strip at a finishing entrance is controlled to be 800 to 850° C. by a rough rolling process; the method comprises the following steps:

[0040] S1: Obtain the target temperature of the titanium strip; the target temperature includes: the final rolling target temperature and the curling target temperature. The target temperature is determined in advance according to the process; the final rolling target temperature is 740-780°C; the curling target temperature is 480-530°C.

[0041] S2: After the titanium strip leaves the finishing mill, the final rolling real-time temperature curve of the titanium strip is obtained by the pyrometer set at the outlet of the finishing mill; the first pyrometer and the second pyrometer are set at the outlet of the finishing mill; the temperature collection range of the first pyrometer and the second pyrometer are both 300-1100°C. The higher temperature of the first pyrometer and the second pyrometer is selected as the input value of the final rolling real-time temperature curve of the titanium strip.

[0042] S3: determining the head allowance length L of the titanium strip head and the tail allowance length L of the titanium strip tail according to the difference T1 between the final rolling real-time temperature of the titanium strip head and the final rolling target temperature;

[0043] In this application, the final rolling real-time temperature is the average value of the final rolling real-time temperature measured 0.1S after the start. In this application, the relationship between the head length L of the titanium strip and the tail length L of the titanium strip and the difference T1 between the final rolling real-time temperature of the titanium strip head and the final rolling target temperature is set as follows:

[0044] T1≤10℃, L=10m;

[0045] 10℃<T1≤20℃, L=8m;

[0046] 20℃<T1≤50℃, L=5m.

[0047] S4: Open the cooling header to cool the titanium strip;

[0048] S5: After the coiler detects the arrival of the titanium strip, the real-time coiling temperature is obtained through the pyrometer provided in front of the coiler, and the water pressure P of the pressurized water opened in front of the coiler is determined according to the difference T2 between the real-time coiling temperature and the target coiling temperature. In this application, the pressurized water refers to the water flow provided at the front end of the coiler for coiling the titanium strip, and the water pressure will affect the coiling effect of the titanium strip. If the water pressure matches, the titanium strip can be coiled as required. If the water pressure is too high or too low, the titanium strip will be unevenly coiled due to the mismatch of the water pressure.

[0049] In the present application, a third pyrometer and a fourth pyrometer are provided in front of the coiler; the temperature collection range of the third pyrometer and the fourth pyrometer is 300-1100° C. The coiling real-time temperature is the average value of the coiling real-time temperature 0.1S after the start of measurement.

[0050] Preferably, the difference T2 between the actual curling temperature and the target curling temperature and the water pressure P of the belt water to be turned on in front of the crimping machine are related to:

[0051] T2<0℃, P=0-2bar, close the cooling header water in advance;

[0052] 0℃<T2≤10℃, P=3~6bar;

[0053] 10℃<T2≤20℃, P=6~8bar;

[0054] 20℃<T2≤50℃, P=8~10bar.

[0055] Example 1

[0056] The layer cooling equipment is located at the rear side of the finishing mill and in front of the coiler. The finishing mill has 7 frames F1-F7, and there are 10 groups of headers in the layer cooling section. Each group contains 4 upper and lower cooling headers. The hot rolling mill production control system is equipped with information collection and command execution electrical components on the rolling line.

[0057] The target thickness of the titanium strip is set to 1.5mm, the rolling speed is set to 12m / s, the target final rolling temperature is set to 750℃, and the target curling temperature is set to 490℃. The average value of the final rolling real-time temperature of 0.1S measured at the beginning is 764℃. According to the relationship between the head and tail lengths L of the titanium strip and the difference T1 between the head final rolling real-time temperature and the final rolling target temperature, the head and tail lengths L and 8m of the titanium strip are not cooled by laminar water, but by natural air cooling;

[0058] The titanium strip is cooled by the cooling manifold, and the cooling is stopped when there are 8m left in the titanium strip; the average value of the real-time temperature of the coil measured at 0.1S is 499℃ at the beginning, and the pressure water in front of the coiler is turned on at 6bar according to the relationship between the difference T2 between the real-time temperature of the head coil and the target temperature of the coil and the water pressure P of the opened pressure water.

[0059] Example 2

[0060] The layer cooling equipment is located at the rear side of the finishing mill and in front of the coiler. The finishing mill has 7 frames F1-F7, and there are 10 groups of headers in the layer cooling section. Each group contains 4 upper and lower cooling headers. The hot rolling mill production control system is equipped with information collection and command execution electrical components on the rolling line.

[0061] The target thickness of the titanium strip is set to 2.5mm, the rolling speed is set to 9m / s, the target final rolling temperature is set to 765℃, and the target curling temperature is set to 505℃. At the beginning, the average final rolling real-time temperature of 0.1S is measured to be 772℃. According to the relationship between the head and tail lengths L of the titanium strip and the difference T1 between the head final rolling real-time temperature and the final rolling target temperature, the head and tail lengths L and 10m of the titanium strip are not cooled by laminar water, but by natural air cooling.

[0062] The titanium strip is cooled by the cooling manifold, and the cooling is stopped when there are 10m left in the titanium strip; the average value of the real-time temperature of the coil measured at 0.1S is 518℃ at the beginning, and the pressure water in front of the coiler is turned on at 7bar according to the relationship between the difference T2 between the real-time temperature of the head coil and the target temperature of the coil and the water pressure P of the opened pressure water.

[0063] Example 3

[0064] The layer cooling equipment is located at the rear side of the finishing mill and in front of the coiler. The finishing mill has 7 frames F1-F7, and there are 10 groups of headers in the layer cooling section. Each group contains 4 upper and lower cooling headers. The hot rolling mill production control system is equipped with information collection and command execution electrical components on the rolling line.

[0065] The target thickness of the titanium strip is set to 3.7mm, the rolling speed is set to 4.5m / s, the target final rolling temperature is set to 770℃, and the target coiling temperature is set to 530℃. At the beginning, the average final rolling real-time temperature of 0.1S is measured to be 790℃. According to the relationship between the head and tail lengths L of the titanium strip and the difference T1 between the head final rolling real-time temperature and the final rolling target temperature, the head and tail lengths L and 8m of the titanium strip are not cooled by laminar water, but by natural air cooling;

[0066] The titanium strip is cooled by the cooling manifold, and the cooling is stopped when there are 8m left in the titanium strip. The average value of the real-time temperature of the coil measured at 0.1S at the beginning is 523℃. According to the relationship between the difference T2 between the real-time temperature of the head coil and the target temperature of the coil and the water pressure P of the opened water pressure, the water pressure in front of the coiler is turned on at 1bar. When T2 is less than the target temperature of the coil, the water in the cooling manifold is added in advance for natural air cooling.

[0067] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or replace some or all of the technical features therein with equivalents. However, these modifications or replacements do not cause the essence of the corresponding technical solutions to deviate from the scope of the technical solutions of the embodiments of the present invention.

Claims

1. A method for controlling the temperature of a coiled titanium strip, wherein the titanium strip is heated to a temperature of 890-950°C by a heating furnace, and the temperature of the titanium strip at the entrance of the finishing rolling is controlled to be 800-850°C by a rough rolling process; characterized in that: The following steps are involved: S1: obtaining the target temperature of the titanium strip; S2: After the titanium strip leaves the finishing mill, the final rolling real-time temperature curve of the titanium strip is obtained through a pyrometer set at the exit of the finishing mill; S3: determining the head allowance length L of the titanium strip head and the tail allowance length L of the titanium strip tail according to the difference T1 between the final rolling real-time temperature of the titanium strip head and the final rolling target temperature; S4: Open the cooling header to cool the titanium strip; S5: After the coiler detects the arrival of the titanium strip, the real-time coiling temperature is obtained through the pyrometer installed in front of the coiler. According to the difference T2 between the real-time coiling temperature and the target coiling temperature, the water pressure P of the strip pressing water opened in front of the coiler is determined.

2. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: In the step S1, the target temperature includes a finishing rolling target temperature and a curling target temperature.

3. A temperature control method for a coiled titanium strip according to claim 2, characterized in that: In S1, the target temperature is determined in advance according to the process; the final rolling target temperature is 740-780°C; and the curling target temperature is 480-530°C.

4. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: In the S2, a first pyrometer and a second pyrometer are arranged at the finishing exit; the temperature collection range of the first pyrometer and the second pyrometer are both 300-1100°C.

5. A temperature control method for a coiled titanium strip according to claim 4, characterized in that: In S2, the higher temperature of the first pyrometer and the second pyrometer is selected as the input value of the final rolling real-time temperature curve of the titanium strip.

6. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: The final rolling real-time temperature is the average value of the final rolling real-time temperature measured 0.1S after the start.

7. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: In S3, the relationship between the head allowance length L of the titanium strip head and the tail allowance length L of the titanium strip tail and the difference T1 between the final rolling real-time temperature of the titanium strip head and the final rolling target temperature is: T1≤10℃, L=10m; 10℃<T1≤20℃, L=8m; 20℃<T1≤50℃, L=5m.

8. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: A third pyrometer and a fourth pyrometer are arranged in front of the coiler; the temperature collection ranges of the third pyrometer and the fourth pyrometer are both 300-1100°C.

9. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: The real-time curling temperature is the average value of the real-time curling temperature 0.1S after the initial measurement.

10. A temperature control method for a coiled titanium strip according to claim 1, characterized in that: The relationship between the difference T2 between the actual curling temperature and the target curling temperature and the water pressure P of the belt water that needs to be turned on in front of the crimping machine is: T2<0℃, P=0-2bar, close the cooling header water in advance; 0℃<T2≤10℃, P=3~6bar; 10℃<T2≤20℃, P=6~8bar; 20℃<T2≤50℃, P=8~10bar.

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