Production method of titanium alloy cold-rolled coil

Abstract

The invention discloses a production method of a titanium alloy cold-rolled coil, and relates to the technical field of titanium material rolling. Before cold rolling, the hole in the head of the hot-rolled strip is connected with the head leading tape through the head connecting strip, and the hole in the tail of the hot-rolled strip is connected with the tail leading tape through the tail connecting strip. The tail leading tape is wound on the uncoiler; and the head leading tape penetrates through the reversible rolling mill and is wound on the coiling machine. And carrying out multi-pass reversible cold rolling on the hot-rolled strip billet through a coiling machine, an uncoiling machine and a reversible rolling mill to prepare a finished cold-rolled coil. On one hand, the head connecting strip, the head leading strip, the tail connecting strip and the tail leading strip can be connected with the titanium alloy hot-rolled strip blank through non-titanium alloy materials such as stainless steel, and the rolling production cost is reduced. And on the other hand, the connecting strength of the leading tapes and the hot-rolled strip billet is enhanced, and the situation that the production efficiency is affected due to the fact that the leading tapes and the hot-rolled strip billet are broken in the cold rolling process is avoided.

Description

Technical Field

[0001] The invention relates to the technical field of titanium material rolling, and in particular to a production method of a titanium alloy cold-rolled coil. Background Art

[0002] Reversible rolling of titanium alloy cold rolled coils is a process of rolling hot rolled strips back and forth using a single stand or a double stand. Compared with continuous rolling, the production of titanium alloy cold rolled strips by reversible cold rolling has the characteristics of low investment and flexible production organization. In the reversible rolling process of titanium alloy cold rolled strips, it is necessary to connect the lead tape at the head and tail of the hot rolled strip. The lead tape replaces the head and tail of the hot rolled strip and is wound with the rolling equipment, so that the head and tail of the hot rolled strip can be hot rolled, thereby improving the yield rate of titanium alloy hot rolled strips.

[0003] The existing technology directly connects the head and tail of the hot-rolled strip with the lead strip welding joint. When stainless steel and other dissimilar materials are used for lead strip welding, due to the difference in physical properties such as thermal expansion coefficient and yield strength between titanium alloy and stainless steel, stress concentration is easy to occur in the welded joint, resulting in strip breakage during rolling. When titanium alloy lead strips of the same material as the hot-rolled strip are used for welding, the lead strips need to be cut off and scrapped after rolling, resulting in an increase in the production cost of titanium alloy cold-rolled coils. Summary of the invention

[0004] The purpose of the present invention is to overcome the defects in the prior art and provide a production method of titanium alloy cold-rolled coil.

[0005] To achieve the above object, the technical solution of the present invention is as follows: A method for producing a titanium alloy cold-rolled coil comprises the following steps: Openings are provided at the head and tail of the hot-rolled strip; the opening at the head of the hot-rolled strip is connected to the head lead through a head connecting strip, and the opening at the tail of the hot-rolled strip is connected to the tail lead through a tail connecting strip; the head connecting strip is made of the same material as the head lead, and the tail connecting strip is made of the same material as the tail lead; The tail lead is wound on an unwinder; the head lead passes through a reversible rolling mill and is wound on a coiler; the hot-rolled strip is subjected to multiple cold rollings by the coiler, the unwinder and the reversible rolling mill, and rolling oil is sprayed on the hot-rolled strip during the rolling process to prepare a titanium alloy cold-rolled coil; Degreasing the titanium alloy cold-rolled coil; The degreased titanium alloy cold-rolled coil is vacuum annealed to prepare a finished cold-rolled coil.

[0006] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the step of connecting the opening at the head of the hot-rolled strip blank to the head leading strip through the head connecting strip and connecting the opening at the tail of the hot-rolled strip blank to the tail leading strip through the tail connecting strip includes: The head of the hot-rolled strip blank is stacked on the top overlapping area of the head leading strip. The first end of the head connecting strip is welded to the top surface of the head leading strip, and the second end of the head connecting strip is passed through the opening and welded to the top surface of the head leading strip; The tail of the hot-rolled strip blank is stacked on the top overlapping area of the tail leading strip. The first end of the tail connecting strip is welded to the top surface of the tail leading strip, and the second end of the tail connecting strip is passed through the opening and welded to the top surface of the tail leading strip.

[0007] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the end of the head leading strip is cut to form the head connecting strip, and the first end of the head connecting strip is integrally formed with the head leading strip; The end of the tail leading strip is cut to form the tail connecting strip, and the first end of the tail connecting strip is integrally formed with the tail leading strip.

[0008] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the step of connecting the opening at the head of the hot-rolled strip blank to the head leading strip through the head connecting strip and connecting the opening at the tail of the hot-rolled strip blank to the tail leading strip through the tail connecting strip includes: A first connecting hole is provided on the top of the head leading strip. The first end of the head connecting strip is passed through the connecting hole, the second end of the head connecting strip is passed through the opening, and the first end and the second end of the head connecting strip are welded and connected; A second connecting hole is provided on the top of the tail leading strip. The first end of the tail connecting strip is passed through the second connecting hole, the second end of the tail connecting strip is passed through the opening, and the first end and the second end of the tail connecting strip are welded and connected.

[0009] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the diameter of the mandrel of the uncoiler is D1, the horizontal distance between the center of the working roll of the reversing mill and the center of the mandrel of the uncoiler is L1, and the length S1 of the tail leading strip is greater than L1 + 4π*D1.

[0010] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the diameter of the mandrel of the coiler is D2, the horizontal distance between the center of the working roll of the reversing mill and the center of the mandrel of the coiler is L2, and the length S2 of the head leading strip is greater than L2 + 4π*D2.

[0011] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the steps of performing multi-pass cold rolling on the hot-rolled strip blank include: when the deviation d between the head and tail thickness of the hot-rolled strip blank and the middle thickness of the hot-rolled strip blank is less than 1%, the number of cold rolling passes for the hot-rolled strip blank is N; when the deviation d between the head and tail thickness of the hot-rolled strip blank and the middle thickness of the hot-rolled strip blank is greater than or equal to 1% and less than 3%, the number of cold rolling passes for the hot-rolled strip blank is N + 1; when the deviation d between the head and tail thickness of the hot-rolled strip blank and the middle thickness of the hot-rolled strip blank is greater than or equal to 3% and less than 5%, the number of cold rolling passes for the hot-rolled strip blank is N + 2.

[0012] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the step of performing vacuum annealing on the degreased titanium alloy cold-rolled coils includes: Performing staged annealing on the titanium alloy cold-rolled coils: in the first stage, the temperature is raised to 100 - 200 °C and held for 2 h; in the second stage, the temperature is raised to 400 - 500 °C within 4 - 6 h and held for 4 - 6 h; in the third stage, the temperature is raised to 600 - 650 °C within 6 - 10 h and held for 8 - 15 h.

[0013] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, after the step of performing vacuum annealing on the degreased titanium alloy cold-rolled coils, it further includes: Performing tension leveling on the titanium alloy cold-rolled coils, with the uncoiling tension being 30 - 100 KN, the tension leveling tension being 200 - 1500 KN, and the tension leveling speed being 10 - 35 m / min.

[0014] According to the production method of titanium alloy cold-rolled coils provided by the embodiments of the present invention, the thickness of the head leading strip and the thickness of the tail leading strip are 3 / 5 - 1 of the thickness of the hot-rolled strip blank; the width of the head leading strip and the width of the tail leading strip are 1 / 5 - 1 / 2 of the width of the hot-rolled strip blank.

[0015] The advantages and beneficial effects of the present invention are as follows: The production method of the titanium alloy cold-rolled coil provided by the present application is such that the opening at the head of the hot-rolled strip blank before cold rolling is connected to the head leading strip through the head connecting strip, and the opening at the tail of the hot-rolled strip blank is connected to the tail leading strip through the tail connecting strip. The tail leading strip is wound around the uncoiler; the head leading strip passes through the reversing mill and is wound around the coiler. Then, the hot-rolled strip blank is subjected to multi-pass reversing cold rolling by the coiler, uncoiler, and reversing mill to prepare the finished cold-rolled coil. On the one hand, the head connecting strip, head leading strip, tail connecting strip, and tail leading strip can all use non-titanium alloy materials such as stainless steel to realize the connection between the leading strip and the titanium alloy hot-rolled strip blank, reducing the rolling production cost. On the other hand, the head of the hot-rolled strip blank is connected to the head leading strip through the opening, and the tail of the hot-rolled strip blank is connected to the tail leading strip through the opening, enhancing the connection strength between each leading strip and the hot-rolled strip blank and avoiding the breakage of each leading strip and the hot-rolled strip blank during cold rolling, which affects the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 is a schematic flow chart of the production method of the titanium alloy cold-rolled coil in an embodiment of the present invention; Figure 2 is one of the schematic diagrams of the connection between the hot-rolled strip blank and each leading strip in an embodiment of the present invention; Figure 3 is Figure 2 the schematic cross-sectional structure diagram of; Figure 4 is another schematic diagram of the connection between the hot-rolled strip blank and each leading strip in an embodiment of the present invention; Figure 5 is Figure 4 the schematic cross-sectional structure diagram of; Figure 6 is still another schematic diagram of the connection between the hot-rolled strip blank and each leading strip in an embodiment of the present invention; Figure 7 is Figure 6 the schematic cross-sectional structure diagram of; Figure 8 is the schematic diagram of the rolling equipment of the titanium alloy cold-rolled coil in an embodiment of the present invention; Figure 9 is the process curve of vacuum annealing for the titanium alloy cold-rolled coil in an embodiment of the present invention.

[0017] 1. Hot-rolled strip blank; 11. Opening; 2. Head leading strip; 21. Head connecting strip; 22. First connecting hole; 3. Tail leading strip; 31. Tail connecting strip; 32. Second connecting hole; 4. Uncoiler; 5. Coiler; 6. Reversing mill. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] The following further describes the specific embodiments of the present invention in conjunction with the drawings and embodiments. The following embodiments are only used to more clearly illustrate the technical solutions of the present invention and cannot be used to limit the protection scope of the present invention.

[0019] Figure 1 is a schematic flow chart of the production method of titanium alloy cold-rolled coils in an embodiment of the present invention. As Figure 1 shown, the present application provides a production method of titanium alloy cold-rolled coils, including the following steps: S1: Open holes are provided at both the head and the tail of the hot-rolled strip blank. The hole at the head of the hot-rolled strip blank is connected to the head leading strip through the head connecting strip, and the hole at the tail of the hot-rolled strip blank is connected to the tail leading strip through the tail connecting strip. The head connecting strip and the head leading strip are made of the same material, and the tail connecting strip and the tail leading strip are made of the same material; S2: The tail leading strip is wound around the uncoiler; the head leading strip passes through the reversing mill and is wound around the coiler; the hot-rolled strip blank is subjected to multi-pass cold rolling by the coiler, the uncoiler and the reversing mill, and rolling oil is sprayed on the hot-rolled strip blank during the rolling process to prepare titanium alloy cold-rolled coils; S3: Degrease the titanium alloy cold-rolled coils; S4: Perform vacuum annealing on the degreased titanium alloy cold-rolled coils to prepare finished cold-rolled coils.

[0020] In the production method of titanium alloy cold-rolled coils provided by the present application, before cold rolling, the hole at the head of the hot-rolled strip blank is connected to the head leading strip through the head connecting strip, and the hole at the tail of the hot-rolled strip blank is connected to the tail leading strip through the tail connecting strip. The tail leading strip is wound around the uncoiler; the head leading strip passes through the reversing mill and is wound around the coiler. Then, the hot-rolled strip blank is subjected to multi-pass reversing cold rolling by the coiler, the uncoiler and the reversing mill to prepare finished cold-rolled coils. On the one hand, the head connecting strip, the head leading strip, the tail connecting strip and the tail leading strip can all use non-titanium alloy materials such as stainless steel to realize the connection between the leading strip and the titanium alloy hot-rolled strip blank, reducing the rolling production cost. On the other hand, the head of the hot-rolled strip blank is connected to the head leading strip through the hole, and the tail of the hot-rolled strip blank is connected to the tail leading strip through the hole, enhancing the connection strength between each leading strip and the hot-rolled strip blank, and avoiding the breakage of each leading strip and the hot-rolled strip blank during cold rolling, which affects the production efficiency.

[0021] It should be noted that in reversing rolling, rolling oil needs to be sprayed on the hot-rolled strip blank to reduce the friction coefficient and reduce the generation of cracks in the rolled strip coil. Before annealing, the titanium alloy cold-rolled coils need to be degreased to avoid damage to the surface of the titanium alloy cold-rolled coils during annealing.

[0022] In some embodiments, before degreasing the titanium alloy cold-rolled coils, it further includes: texturing the defective area of the titanium alloy cold-rolled coils, increasing one or two passes of rolling on the titanium alloy cold-rolled coils with a constant roll gap, and repairing the defective area on the premise that the target thickness of the titanium alloy cold-rolled coils remains unchanged.

[0023] In some embodiments, the distance between the opening located at the head of the hot-rolled strip blank and the edge of the head of the hot-rolled strip blank is 10 - 20 mm. Multiple openings are arranged at intervals along the width direction of the hot-rolled strip blank and are symmetrically arranged with respect to the center line of the hot-rolled strip blank to avoid stress concentration during rolling and prevent the occurrence of strip breakage accidents. The distance between the opening located at the tail of the hot-rolled strip blank and the edge of the tail of the hot-rolled strip blank is 10 - 20 mm. Multiple openings are arranged at intervals along the width direction of the hot-rolled strip blank and are also symmetrically arranged with respect to the center line of the hot-rolled strip blank to avoid stress concentration during rolling and prevent the occurrence of strip breakage accidents.

[0024] In some embodiments, the opening can be a circular hole or a square hole. The diameter of the circular hole is 5 - 10 mm, and the side length of the square hole is 5 - 10 mm. Specifically, it can be adjusted according to the thickness of the hot-rolled strip blank to meet the tension requirements of reversible rolling.

[0025] In some embodiments, the material of the head connecting strip and the head leading strip can be stainless steel, and the material of the tail connecting strip and the tail leading strip can also be stainless steel to reduce the rolling cost.

[0026] Figure 2 is one of the schematic diagrams showing the connection between the hot-rolled strip blank and each leading strip in the embodiments of the present invention. Figure 3 is Figure 2 the schematic cross-sectional structure diagram of Figure 2 and Figure 3 As shown, the steps of connecting the opening at the head of the hot-rolled strip blank to the head leading strip through the head connecting strip and connecting the opening at the tail of the hot-rolled strip blank to the tail leading strip through the tail connecting strip include: stacking the head of the hot-rolled strip blank on the top overlapping area of the head leading strip, welding the first end of the head connecting strip to the top surface of the head leading strip, and passing the second end of the head connecting strip through the opening and welding it to the top surface of the head leading strip. Stacking the tail of the hot-rolled strip blank on the top overlapping area of the tail leading strip, welding the first end of the tail connecting strip to the top surface of the tail leading strip, and passing the second end of the tail connecting strip through the opening and welding it to the top surface of the tail leading strip. The welding can be carried out by resistance welding or argon arc welding, the weld width > 3 mm, and the weld height > 0.5 mm to ensure that the welding strength meets the requirements.

[0027] In some embodiments, flanges are provided at the second ends of both the head connecting strip and the tail connecting strip, and the length of the flange is 1 - 3 mm to increase the welding contact area between the head connecting strip and the head leading strip and increase the welding contact area between the tail connecting strip and the tail leading strip.

[0028] In some embodiments, rounded corners are provided at the welding joints between the head connecting strip and the head leading strip, and the radius R of the rounded corner is 2 - 3 mm to reduce stress concentration at the welding joints. Rounded corners are provided at the welding joints between the tail connecting strip and the tail leading strip, and the radius R of the rounded corner is 2 - 3 mm to reduce stress concentration at the welding joints.

[0029] Figure 4 It is the second schematic diagram showing the connection between the hot-rolled strip blank and each leading strip in the embodiment of the present invention. Figure 5 It is Figure 4 the schematic cross-sectional structure diagram of, as Figure 4 and Figure 5 shown, the end of the head leading strip is cut to form a head connection strip, and the first end of the head connection strip is integrally formed with the head leading strip; the end of the tail leading strip is cut to form a tail connection strip, and the first end of the tail connection strip is integrally formed with the tail leading strip. Since the first end of the head connection strip is integrally formed with the head leading strip, the connection strength between the first end of the head connection strip and the head leading strip is enhanced. Similarly, since the first end of the tail connection strip is integrally formed with the tail leading strip, the connection strength between the first end of the tail connection strip and the tail leading strip is enhanced.

[0030] Figure 6 It is the third schematic diagram showing the connection between the hot-rolled strip blank and each leading strip in the embodiment of the present invention. Figure 7 It is Figure 6 the schematic cross-sectional structure diagram of, as Figure 6 and Figure 7 shown, the steps of connecting the opening at the head of the hot-rolled strip blank to the head leading strip through the head connection strip and connecting the opening at the tail of the hot-rolled strip blank to the tail leading strip through the tail connection strip include: Set a first connection hole at the top of the head leading strip, pass the first end of the head connection strip through the connection hole, pass the second end of the head connection strip through the opening, and weld the first end and the second end of the head connection strip; Set a second connection hole at the top of the tail leading strip, pass the first end of the tail connection strip through the second connection hole, pass the second end of the tail connection strip through the opening, and weld the first end and the second end of the tail connection strip.

[0031] Figure 8 It is the schematic diagram of the rolling equipment for titanium alloy cold-rolled coils in the embodiment of the present invention, as Figure 8 shown, the diameter of the mandrel of the uncoiler is D1, the horizontal distance between the center of the working roll of the reversing mill and the center of the mandrel of the uncoiler is L1, and the length S1 of the tail leading strip is greater than L1 + 4π*D1. By setting the length S1 of the tail leading strip to be greater than L1 + 4π*D1, it is ensured that the tail leading strip winds around the mandrel of the uncoiler for more than 4 turns, ensuring that even if the diameter of the mandrel changes due to the winding of the strip coil during the rolling process, the leading strip can still maintain sufficient tension, avoiding breakage of the strip caused by tension fluctuations.

[0032] In some embodiments, the diameter of the coiler mandrel is D2, the horizontal distance between the center of the reversible rolling mill working roll and the center of the coiler mandrel is L2, and the length S2 of the head lead is greater than L2+4π*D2. By setting the length S2 of the head lead to be greater than L2+4π*D2, it is ensured that the head lead wraps around the coiler mandrel for more than 4 turns, and it is ensured that even if the mandrel diameter changes due to the winding of the strip during the rolling process, the lead can still maintain sufficient tension to avoid breaking of the strip due to tension fluctuations.

[0033] In some embodiments, the step of performing multiple cold rolling passes on the hot-rolled strip includes: when the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d<1%, the number of cold rolling passes on the hot-rolled strip is N; when the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d≥1%, and d<3%, the number of cold rolling passes on the hot-rolled strip is N+1; when the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d≥3%, and d<5%, the number of cold rolling passes on the hot-rolled strip is N+2.

[0034] For example, before rolling, the head thickness, tail thickness and middle thickness of the hot-rolled strip are measured and averaged. The middle thickness is 4.39mm, the tail thickness is 4.51mm, and the head thickness is 4.49mm. Since the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d≥1%, and d<3%, an additional pass is added to the original rolling pass. In this pass, constant roll gap rolling is first used to roll the overall thickness of the hot-rolled strip to 4.39mm, so that the head and tail thicknesses are consistent with the middle thickness, and then the normal rolling system is used for rolling to improve the cold rolling yield rate.

[0035] Figure 9 : is the process curve of vacuum annealing of titanium alloy cold-rolled coil in the embodiment of the present invention, such as Figure 9As shown in the figure, the step of vacuum annealing the degreased titanium alloy cold-rolled coil includes: annealing the titanium alloy cold-rolled coil in stages: in the first stage, the temperature rises to 100-200°C and is kept for 2 hours; in the second stage, the temperature rises to 400-500°C within 4-6 hours and is kept for 4-6 hours; in the third stage, the temperature rises to 600-650°C within 6-10 hours and is kept for 8-15 hours. The first stage is a low-temperature preheating stage, in which the temperature is slowly raised to eliminate the cold rolling residual stress and avoid deformation or cracking of the coil due to a sudden temperature change. Titanium alloy has poor thermal conductivity and rapid heating is prone to thermal stress. This stage is a "buffer" for subsequent heating to ensure uniform temperature. The second stage is a medium-temperature soaking stage, which further diffuses atoms, partially eliminates work hardening, and prepares for high-temperature recrystallization. In this temperature range, dislocations begin to move, partially restore lattice distortion, reduce material internal stress, and reduce high-temperature holding time. The third stage is the high temperature recrystallization stage, which achieves complete recrystallization, restores plasticity, and refines grains. After cold rolling of titanium alloy, the grains are elongated, and this temperature triggers recrystallization, forming uniform equiaxed grains and eliminating work hardening.

[0036] In some embodiments, the cooling speed of the titanium alloy cold-rolled coil is controlled by replacing the cooling cover after the third stage of heat preservation. The cooling speed is controlled by replacing the cooling cover to prevent new stress or tissue defects caused by excessive cooling. The coil is cooled to a low temperature and then taken out of the furnace to avoid oxidation by high-temperature contact with air, while ensuring that the residual heat of the coil is fully released to stabilize the final tissue performance. The cooling speed can be adjusted by increasing or decreasing the number of cooling cover layers or thickness. When the cooling speed needs to be accelerated, the number of cooling cover layers is reduced. When the cooling speed needs to be reduced, the number of cooling cover layers is increased.

[0037] In some embodiments, after the step of vacuum annealing the degreased titanium alloy cold-rolled coil, the titanium alloy cold-rolled coil is further subjected to tension straightening, with an uncoiling tension of 30-100KN, a tension straightening tension of 200-1500KN, and a tension straightening speed of 10-35m / min. The internal residual stress of the vacuum annealed titanium alloy cold-rolled coil may cause the coil to have plate shape problems such as edge waves, middle waves, and warping. Through the synergistic effect of stretching and bending the titanium alloy cold-rolled coil through tension straightening, the coil is plastically deformed to correct local waves or bends. During tension straightening, the elongation of the titanium alloy cold-rolled coil is 0.8%-1.5% to correct the plate shape.

[0038] In some embodiments, the thickness of the head leader strip and the thickness of the tail leader strip are 3 / 5 - 1 of the thickness of the hot-rolled strip blank; the width of the head leader strip and the width of the tail leader strip are 1 / 5 - 1 / 2 of the width of the hot-rolled strip blank. During cold rolling, the yield strength of the head leader strip needs to be greater than the coiling tension of the coiler, and the yield strength of the tail leader strip needs to be greater than the coiling tension of the uncoiler. The yield strengths of the head leader strip and the tail leader strip depend on their own widths and thicknesses. The thickness of the leader strip can be 3 / 5 - 1 of the thickness of the hot-rolled strip blank; the width of the leader strip can be 1 / 5 - 1 / 2 of the width of the hot-rolled strip blank, so that the yield strength of the head leader strip is greater than the coiling tension of the coiler, ensuring that the head leader strip has sufficient strength for use; and the yield strength of the tail leader strip needs to be greater than the coiling tension of the uncoiler, ensuring that the tail leader strip has sufficient strength for use.

[0039] The specific production process of the titanium alloy cold-rolled coil of the present application is as follows: Place the hot-rolled strip blank on the uncoiler, and weld the head of the hot-rolled strip blank to the head leader strip. Before the first pass of rolling, pass the head leader strip through the roll gap of the reversing mill and wind it around the coiler mandrel on the other side to establish the tension required for rolling. When the tail of the hot-rolled strip blank reaches during the first pass of rolling, weld the tail of the hot-rolled strip blank to the tail leader strip, and wind the tail leader strip around the uncoiler mandrel. The uncoiler and the coiler run in reverse to perform the second pass of rolling. Each time when rolling reaches the connection between the hot-rolled strip blank and each leader strip, the uncoiler and the coiler run in reverse until the thickness of the hot-rolled strip blank reaches the target thickness of the finished cold-rolled coil.

[0040] The above are only the preferred embodiments of the present invention. It should be noted that for those of ordinary skill in the art, without departing from the technical principle of the present invention, several improvements and refinements can be made, and these improvements and refinements should also be regarded as the protection scope of the present invention.

Claims

1. A method for producing a titanium alloy cold-rolled coil, characterized in that: The following steps are involved: Openings are provided at the head and tail of the hot-rolled strip; the opening at the head of the hot-rolled strip is connected to the head lead through a head connecting strip, and the opening at the tail of the hot-rolled strip is connected to the tail lead through a tail connecting strip; the head connecting strip is made of the same material as the head lead, and the tail connecting strip is made of the same material as the tail lead; The tail lead is wound on an unwinder; the head lead passes through a reversible rolling mill and is wound on a coiler; the hot-rolled strip is subjected to multiple cold rollings by the coiler, the unwinder and the reversible rolling mill, and rolling oil is sprayed on the hot-rolled strip during the rolling process to prepare a titanium alloy cold-rolled coil; Degreasing the titanium alloy cold-rolled coil; The degreased titanium alloy cold-rolled coil is vacuum annealed to prepare a finished cold-rolled coil.

2. The method for producing a titanium alloy cold-rolled coil according to claim 1, characterized in that: The step of connecting the opening at the head of the hot-rolled strip to the head lead belt through a head connecting strip, and connecting the opening at the tail of the hot-rolled strip to the tail lead belt through a tail connecting strip comprises: The head of the hot-rolled strip is stacked on the top overlapping area of ​​the head leader, the first end of the head connecting strip is welded to the top surface of the head leader, and the second end of the head connecting strip is passed through the opening and welded to the top surface of the head leader; The tail of the hot-rolled strip is stacked on the top overlapping area of ​​the tail leader, the first end of the tail connecting strip is welded to the top surface of the tail leader, and the second end of the tail connecting strip is passed through the opening and welded to the top surface of the tail leader.

3. The method for producing a titanium alloy cold-rolled coil according to claim 2, characterized in that: Cutting the end of the head lead to form the head connecting strip, wherein the first end of the head connecting strip is integrally formed with the head lead; The end of the tail leader is cut to form the tail connecting strip, and the first end of the tail connecting strip is integrally formed with the tail leader.

4. The method for producing a titanium alloy cold-rolled coil according to claim 1, characterized in that: The step of connecting the opening at the head of the hot-rolled strip to the head lead belt through a head connecting strip, and connecting the opening at the tail of the hot-rolled strip to the tail lead belt through a tail connecting strip comprises: A first connection hole is provided at the top of the head lead strip, the first end of the head connection strip is passed through the connection hole, the second end of the head connection strip is passed through the opening, and the first end and the second end of the head connection strip are welded and connected; A second connection hole is provided at the top of the tail leader, the first end of the tail connection strip is passed through the second connection hole, the second end of the tail connection strip is passed through the opening, and the first end and the second end of the tail connection strip are welded and connected.

5. The method for producing a titanium alloy cold-rolled coil according to claim 1, characterized in that: The diameter of the uncoiler mandrel is D1, the horizontal distance between the center of the reversible rolling mill working roll and the center of the uncoiler mandrel is L1, and the length S1 of the tail lead is greater than L1+4π*D1.

6. The method for producing a titanium alloy cold-rolled coil according to claim 1, characterized in that: The diameter of the coiler mandrel is D2, the horizontal distance between the center of the reversible rolling mill working roll and the center of the coiler mandrel is L2, and the length S2 of the head lead is greater than L2+4π*D2.

7. The method for producing a titanium alloy cold-rolled coil according to claim 1, characterized in that: The step of performing multiple cold rolling on the hot-rolled strip comprises: when the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d<1%, the number of cold rolling passes on the hot-rolled strip is N; when the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d≥1%, and d<3%, the number of cold rolling passes on the hot-rolled strip is N+1; when the deviation between the head and tail thickness of the hot-rolled strip and the middle thickness of the hot-rolled strip is d≥3%, and d<5%, the number of cold rolling passes on the hot-rolled strip is N+2.

8. The method for producing a titanium alloy cold-rolled coil according to any one of claims 1 to 7, characterized in that: The step of vacuum annealing the degreased titanium alloy cold-rolled coil comprises: The titanium alloy cold-rolled coil is annealed in stages: in the first stage, the temperature is raised to 100-200°C and kept warm for 2 hours; in the second stage, the temperature is raised to 400-500°C within 4-6 hours and kept warm for 4-6 hours; in the third stage, the temperature is raised to 600-650°C within 6-10 hours and kept warm for 8-15 hours.

9. The method for producing a titanium alloy cold-rolled coil according to claim 8, characterized in that: After the step of vacuum annealing the degreased titanium alloy cold-rolled coil, the method further comprises: The titanium alloy cold-rolled coil is tension-corrected, the uncoiling tension is 30-100 KN, the tension-corrected tension is 200-1500 KN, and the tension-corrected speed is 10-35 m / min.

10. The method for producing a titanium alloy cold-rolled coil according to any one of claims 1 to 7, characterized in that: The thickness of the head lead strip and the thickness of the tail lead strip are 3 / 5-1 of the thickness of the hot-rolled strip; the width of the head lead strip and the width of the tail lead strip are 1 / 5-1 / 2 of the width of the hot-rolled strip.

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