A method for controlling the temperature of a coiled titanium ribbon

Abstract

The application provides a titanium strip coiling temperature control method, and belongs to the technical field of hot rolling method control. The method comprises the following steps: obtaining a target temperature of the titanium strip; after the titanium strip is discharged from a finishing mill, a pyrometer arranged at the outlet of the finishing mill is used to obtain a finishing rolling real-time temperature curve of the titanium strip; the difference between the finishing rolling real-time temperature of the head of the titanium strip and the target temperature of the finishing rolling is used to determine the head allowance length of the titanium strip and the tail allowance length of the titanium strip; a cooling header is started to cool the titanium strip; after the titanium strip reaches a coiling machine, a pyrometer arranged in front of the coiling machine is used to obtain a coiling real-time temperature; and the difference between the coiling real-time temperature and the target temperature of the coiling is used to determine the water pressure of the pressurized water started in front of the coiling machine. The application uses high-temperature rolling to reduce stress concentration in the deformation process; and uses laminar flow cooling control in the continuous rolling mill group to improve the post-rolling cooling speed, and to improve problems such as coarse grains and uneven structure.

Description

Technical Field

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

[0002] Titanium has excellent properties such as light weight, high specific strength, corrosion resistance, and high temperature resistance, and 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 enable more slip systems to be activated. Their activation helps to coordinate the plastic deformation of the close-packed hexagonal metal, greatly reducing the critical shear stress of non-basal slip in the close-packed hexagonal metal and alleviating 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 brittle fracture more likely to occur in subsequent practical applications, and performance fluctuations are prone to occur 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 temperature control method for a coiled titanium strip is provided.

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

[0006] A method for controlling the temperature of a coiled titanium strip comprises heating the titanium strip to a temperature of 890-950° C. in a heating furnace, and controlling the temperature of the titanium strip at a finishing rolling inlet to 800-850° C. through a rough rolling process. The method comprises the following steps:

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

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

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

[0010] S4: Open the cooling manifold 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 coiling target temperature, the water pressure P of the strip pressing water opened in front of the coiler is determined.

[0012] Furthermore, in said S1, said 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 finishing target temperature is 740-780°C; and the curling target temperature is 480-530°C.

[0014] Furthermore, in said S2, a first pyrometer and a second pyrometer are provided at the finishing rolling 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] Furthermore, in S3, the relationship between the lead length L of the titanium strip and the lead 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 provided 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 0.1s after the initial measurement.

[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] This invention reduces stress concentration during deformation through high-temperature rolling. It also uses laminar cooling control in the continuous rolling mill to increase the cooling rate after rolling, improving problems such as coarse grains and uneven structure. This significantly improves product quality, reduces costs, and offers excellent 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 following briefly introduces the drawings required for use in the embodiments or the description of the prior art. 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 any 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 and features of the embodiments of the present invention 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 in no way 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 making 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 the exemplary embodiments according to the present invention. As used herein, unless the context clearly indicates otherwise, the singular form is intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0035] Unless otherwise specifically stated, the relative arrangement of the parts and steps, numerical expressions and numerical values ​​set forth 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 those of ordinary skill in the relevant art may not be discussed in detail, but in appropriate cases, the technology, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific value should be interpreted as being merely exemplary and not as a limitation. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0036] In the description of the present invention, it should be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying 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 outline 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 herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. 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 figures. For example, if the device in the 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. Unless 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 comprises heating the titanium strip to a temperature of 890-950° C. in a heating furnace, and controlling the temperature of the titanium strip at a finishing rolling inlet to 800-850° C. through a rough rolling process. The method comprises the following steps:

[0040] S1: Obtain target temperatures for the titanium strip. Target temperatures include: final rolling target temperature and coiling target temperature. Target temperatures are determined in advance based on the process. Final rolling target temperature is 740-780°C; coiling target temperature is 480-530°C.

[0041] S2: After the titanium strip exits the finishing mill, a pyrometer installed at the mill exit acquires the strip's real-time final rolling temperature curve. A first pyrometer and a second pyrometer are installed at the mill exit. Both pyrometers have a temperature acquisition range of 300-1100°C. The higher temperature of the first and second pyrometers is selected as the input value for the strip's real-time final rolling temperature curve.

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

[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 lead length L of the titanium strip and the lead 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 manifold 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 a pyrometer installed in front of the coiler. The water pressure P of the pressurized water opened in front of the coiler is determined based on 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 installed at the front end of the coiler to achieve coiling of the titanium strip. The water pressure will affect the coiling effect of the titanium strip. If the water pressure is matched, the titanium strip can be coiled as required. If the water pressure is too high or too low, the titanium strip will curl unevenly due to the mismatch of water pressure.

[0049] In this application, a third pyrometer and a fourth pyrometer are provided before 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 relationship between the difference T2 between the real-time 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:

[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 instruction execution electrical components on the rolling line.

[0057] The target thickness of the titanium strip was set to 1.5 mm, the rolling speed was 12 m / s, the target finishing temperature was 750°C, and the target coiling temperature was 490°C. The average finishing temperature measured at the start of the test for 0.1 s was 764°C. Based on the relationship between the lead and tail lengths (L) and the difference (T1) between the lead finishing temperature and the target finishing temperature, the lead and tail lengths (L) of the titanium strip were 8 m, with no laminar water cooling and instead natural air cooling.

[0058] The titanium strip is cooled by the cooling manifold, and the cooling is stopped when there is 8m of the titanium strip left. The average value of the real-time temperature of the coil measured at the beginning of 0.1S is 499℃. According to the relationship between the difference T2 of the real-time temperature of the head coil minus 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 6bar.

[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 instruction execution electrical components on the rolling line.

[0061] The target thickness of the titanium strip was set to 2.5mm, the rolling speed was set to 9m / s, the target finishing temperature was set to 765°C, and the target coiling temperature was set to 505°C. The average finishing temperature measured at the beginning of the test for 0.1s was 772°C. Based on the relationship between the lead and tail lengths (L) of the titanium strip and the difference (T1) between the lead finishing temperature and the target finishing temperature, the lead and tail lengths (L) of the titanium strip were set to 10m without laminar water cooling and with natural air cooling.

[0062] The titanium strip is cooled by the cooling manifold, and the cooling is stopped when there is 10m of the titanium strip left. The average value of the real-time temperature of the coil measured at the beginning of 0.1S is 518℃. 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 7bar.

[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 instruction execution electrical components on the rolling line.

[0065] The target thickness of the titanium strip was set to 3.7mm, the rolling speed was set to 4.5m / s, the target finishing temperature was set to 770°C, and the target coiling temperature was set to 530°C. The average finishing temperature measured at the beginning of the test for 0.1s was 790°C. Based on the relationship between the lead and tail lengths (L) of the titanium strip and the difference (T1) between the lead finishing temperature and the target finishing temperature, the lead and tail lengths (L) of the titanium strip were set to 8m without laminar water cooling, but with natural air cooling.

[0066] The titanium strip is cooled by the cooling manifold, and the cooling is stopped when there are 8m of the titanium strip left; the average value of the real-time temperature of the coil measured at 0.1S is 523℃ at the beginning, and the pressure water in front of the coiler is turned on at 1 bar 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. 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 above embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the above 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 process is controlled to be 800-850°C through a rough rolling process; characterized in that: The following steps are involved: S1: Obtain the target temperature of the titanium strip; S2: After the titanium strip leaves the finishing mill, the real-time temperature curve of the titanium strip during final rolling is obtained through a pyrometer installed at the outlet of the finishing mill; S3: determining the lead length L of the titanium strip and the tail length L of the titanium strip according to the difference T1 between the real-time finishing rolling temperature of the titanium strip head and the target finishing rolling temperature; S4: Open the cooling manifold 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 coiling target 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 temperatures include 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 finishing rolling target temperature is 740-780°C; and the curling target temperature is 480-530°C.

4. The temperature control method of a coiled titanium strip according to claim 1, characterized in that: In the S2, a first pyrometer and a second pyrometer are provided at the finishing rolling 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 the above 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. The 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. The temperature control method for a coiled titanium strip according to claim 1, characterized in that: In S3, the relationship between the lead length L of the titanium strip and the lead 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. The temperature control method for a coiled titanium strip according to claim 1, characterized in that: A third pyrometer and a fourth pyrometer are provided in front of the coiler; the temperature collection ranges of the third pyrometer and the fourth pyrometer are both 300-1100°C.

9. The 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 start of measurement.

10. The 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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