A high-speed wire rod rolling production method for GH4169 coil

Abstract

The application provides a GH4169 rod high-speed wire rod rolling production method, comprising the following steps: S1: blank preparation and heating: selecting GH4169 alloy blank, placing the blank in a step-by-step heating furnace or a chamber heating furnace and heating to 1110 DEG C to 1125 DEG C, and keeping the temperature for 2 to 5 hours; S2: rough rolling: sending the heated blank into an initial rolling mill set and a medium rolling mill set to carry out blooming and rough medium rolling, and controlling the rough rolling final rolling temperature to be 1000 DEG C to 1100 DEG C; S3: medium rolling and heat supplement: sending the rough-rolled intermediate blank into the medium rolling mill set to carry out medium rolling. The application provides a GH4169 rod high-speed wire rod rolling production method, through adopting a multi-stage temperature control and rolling process of blooming, rough medium rolling, pre-finishing rolling, finishing rolling and reducing sizing, cooperating with flying shear cutting and water cooling, effectively solving the head tail temperature difference and surface temperature reduction problem in the GH4169 alloy rolling process, ensuring the finishing rolling temperature stability, and being beneficial to obtaining uniform and small grain structure.

Description

Technical Field

[0001] This invention relates to the field of GH4169 wire rod production, and more particularly to a method for producing high-speed wire rod from GH4169 wire rod. Background Technology

[0002] GH4169 is a precipitation-strengthened nickel-based superalloy. Due to its excellent high-temperature strength, fatigue resistance, creep resistance and corrosion resistance below 650℃, it is widely used in aerospace, nuclear power and petrochemical fields to manufacture key components such as turbine disks, blades, casings and high-temperature fasteners.

[0003] Currently, GH4169 alloy wire rod is produced in large coils using hot rolling, which has significant advantages such as high yield, uniform structure, and high production efficiency.

[0004] However, in the current long-process rolling process, the temperature drop at the head and tail and surface of the rolled piece is significant, which leads to unstable finishing rolling temperature. This affects the consistency of product microstructure and properties. At the same time, due to limitations in heating capacity, rolling rhythm and temperature control precision, the existing production process often cannot achieve efficient and stable rolling of large-size billets into large coils. The weight of a single coil is usually small, which cannot meet the downstream users' demand for long lengths and continuous processing.

[0005] Therefore, it is necessary to provide a method for producing high-speed wire rod from GH4169 wire rod to solve the above-mentioned technical problems. Summary of the Invention

[0006] This invention provides a high-speed wire rod rolling production method for GH4169 wire rod, which solves the problem that in the current long-process rolling process, the temperature drop at the beginning and end of the rolled piece and the surface is significant, resulting in unstable finishing temperature and affecting the consistency of product microstructure and properties.

[0007] To solve the above-mentioned technical problems, the present invention provides a method for producing high-speed wire rod from GH4169 wire rod, comprising the following steps: S1: Billet preparation and heating: Select GH4169 alloy billet, place it in a walking beam furnace or chamber furnace and heat it to 1110℃~1125℃, hold it for 2~5 hours; S2: Rough rolling: The heated billet is sent to the primary rolling mill and intermediate rolling mill for billet opening and rough and intermediate rolling. The final rolling temperature of rough rolling is controlled at 1000℃~1100℃. S3: Intermediate rolling and reheating: The intermediate billet after rough rolling is sent to the intermediate rolling mill for intermediate rolling; S4: Head cutting and pre-finishing: Flying shears are set at the exit of the first, second or third intermediate rolling mill for head cutting, and then the mill enters the pre-finishing mill for pre-finishing. S5: Finishing and sizing: The pre-finished rolled piece is sent to the finishing mill for finishing rolling, and then enters the sizing mill for sizing rolling. The finishing rolling temperature is controlled at 850℃~950℃. S6: Air cooling and coiling: The finished wire rod enters the wire drawing machine to form coils. The cooled coils are collected by the coil transport system to form large coils.

[0008] Preferably, the cross-sectional dimensions of the GH4169 alloy billet in step S1 are a square billet (100-120) mm × (100-120) mm or a round billet with an equivalent cross-section.

[0009] Preferably, the total deformation of the billet opening and roughing and intermediate rolling in step S2 is 60% to 85%.

[0010] Preferably, in step S2, the total deformation of the intermediate rolling mill is 50% to 70%, and an induction heating device is installed before the outlet of the intermediate rolling mill to quickly heat the rolled workpiece at a temperature of 1000℃ to 1050℃.

[0011] Preferably, the length of the cut head in step S3 is 50~100mm, and the total deformation of the pre-finish rolling is 30%~50%.

[0012] Preferably, in step S5, both the finishing mill and the sizing mill are equipped with shears at their inlets.

[0013] Preferably, the total deformation of finishing rolling and sizing in step S5 is 30% to 60%.

[0014] Preferably, in step S4, a temperature measuring device is installed 0.5m to 1.5m before the entrance of the pre-finishing mill to continuously scan the temperature field along the entire length of the rolled piece and obtain the surface temperature distribution data of the head, middle and tail sections in real time. When the temperature at the head and tail sections is detected to be more than 15°C lower than that in the middle section, the induction heating device is activated to perform dynamic heating.

[0015] Preferably, in step S5, a rapid air mist cooling device is added between the last stand of the finishing mill and the sizing mill to cool the surface of the rolled piece.

[0016] Preferably, the cooling rate of the aerosol cooling device is 3℃ / s to 8℃ / s, so that the temperature difference between the core and surface of the rolled piece is controlled at ≤50℃.

[0017] Compared with related technologies, the high-speed wire rod rolling production method of GH4169 wire rod provided by the present invention has the following beneficial effects: This invention provides a method for producing high-speed wire rod from GH4169 wire rod. By adopting a multi-stage temperature-controlled rolling process including billet opening, roughing and intermediate rolling, pre-finishing rolling, finishing rolling, and sizing reduction, combined with flying shear head and water cooling, the method effectively solves the problems of head-to-tail temperature difference and surface cooling in the rolling process of GH4169 alloy, ensuring stable finishing rolling temperature and facilitating the acquisition of uniform and fine grain structure. Meanwhile, by optimizing the heating regime, rolling pass allocation, and overall temperature control, combined with the continuous heating capacity of the walking beam furnace and the high-efficiency rolling capacity of the semi-continuous rolling mill, the weight of a single coil has been significantly increased to over 500 kg, meeting the downstream users' demand for long lengths and continuous processing, and improving production efficiency and yield. By controlling the deformation amount and rolling temperature in stages, and coordinating with a water-cooling device for controlled cooling, the problem of internal heat accumulation and overheating caused by the poor thermal conductivity of GH4169 alloy is effectively solved, ensuring the mechanical properties and service reliability of the product. Attached Figure Description

[0018] Figure 1 This is a schematic diagram of the structure of a first embodiment of a high-speed wire rod rolling production method for GH4169 wire rod provided by the present invention. Figure 2 This is a schematic diagram of the second embodiment of a high-speed wire rod rolling production method for GH4169 wire rod provided by the present invention. Detailed Implementation

[0019] The present invention will be further described below with reference to the accompanying drawings and embodiments. Example

[0020] Please refer to the following: Figure 1 ,in, Figure 1 This is a schematic diagram of the structure of a first embodiment of a high-speed wire rod rolling production method for GH4169 wire rod provided by the present invention.

[0021] A method for producing high-speed wire rod from GH4169 wire rod includes the following steps: S1: Billet preparation and heating: Select GH4169 alloy billet, place it in a walking beam furnace or chamber furnace and heat it to 1110℃~1125℃, hold it for 2~5 hours to ensure uniform temperature inside and outside the billet; S2: Rough rolling: The heated billet is sent to the primary rolling mill and intermediate rolling mill for billet opening and rough and intermediate rolling. The final rolling temperature of rough rolling is controlled at 1000℃~1100℃. S3: Intermediate rolling and reheating: The intermediate billet after rough rolling is sent to the intermediate rolling mill for intermediate rolling; S4: Head cutting and pre-finishing: A flying shear is set at the exit of the first, second or third intermediate rolling mill for head cutting, and then the wire rod enters the pre-finishing mill for pre-finishing. The diameter of the finished wire rod is Φ5.5mm~Φ20.0mm. S5: Finishing and sizing: The pre-finished rolled piece is sent to the finishing mill for finishing rolling, and then enters the sizing mill for sizing rolling. The finishing rolling temperature is controlled at 850℃~950℃. S6: Air cooling and coiling: The finished wire rod enters the wire drawing machine to form coils. The cooled coils are collected by the coil transport system to form large coils.

[0022] The GH4169 large coil wire prepared by the above method has a grain size finer than ASTM grade 8, uniform precipitation of γ″ strengthening phase, no defects such as cracks or folds on the surface of the wire, and a single coil weight ≥500kg.

[0023] The cross-sectional dimensions of the GH4169 alloy billet in step S1 are (100~120) mm × (100~120) mm square billet or equivalent cross-sectional round billet.

[0024] The total deformation of the billet during the roughing and intermediate rolling processes in step S2 is 60% to 85%.

[0025] In step S2, the total deformation of the intermediate rolling mill is 50% to 70%, and an induction heating device is installed before the outlet of the intermediate rolling mill to quickly heat the rolled workpiece at a temperature of 1000℃ to 1050℃.

[0026] Induction heating devices are used to compensate for the temperature drop at the head, tail, and surface of the rolled piece.

[0027] In step S3, the length of the cut head is 50-100mm, and the total deformation of the pre-finish rolling is 30%-50%.

[0028] In step S5, both the finishing mill and the sizing mill are equipped with shears at their inlets.

[0029] The clamp cutter is used to quickly cut off rolled parts in the event of an accident.

[0030] In step S5, the total deformation of finishing rolling and sizing is 30% to 60%.

[0031] In this embodiment, the chemical composition of the billet by mass percentage is: C: 0.018%; Si: 0.16%; Mn: 0.087%; P: 0.009%; S: 0.001%; ​​Cr: 18.95%; Ni: 51.44%; Al: 0.45%; Cu: 0.033%; Ti: 1.022%; Mo: 3.08%; Nb: 5.23%; Co: 0.15%; B: 0.03%; with the balance being Fe. Smelting of steel billets: After vacuum induction smelting and electroslag remelting, it is forged into square billets.

[0032] Billet heating: When heating billets in a pusher-type heating furnace, the heating temperature of the billets shall be controlled according to the following requirements: Preheating section: 880℃; heating section: 800~1125℃; heat spreader section: 1100~1125℃; compensation heating: 1100℃.

[0033] Rolling of billets: On a high-speed wire rod mill, square billets are rolled into wire rods with a diameter of 8.0 mm. The rolling temperature regime is as follows: Initial rolling temperature: 1125℃; Final rolling temperature (coil-out temperature): 1020℃; Pan Yuan pickling: The coils are fed into the pickling line for pickling. After pickling, the black stainless steel coils are turned into white stainless steel wire rods, which are the finished wire rods. Component performance testing:

[0034] The working principle of the high-speed wire rod rolling production method for GH4169 wire rod provided by this invention is as follows: When using, S1: billet preparation and heating: Select GH4169 alloy billet, place it in a walking beam furnace or chamber furnace and heat it to 1110℃~1125℃, and hold it for 2~5 hours; S2: Rough rolling: The heated billet is sent to the primary rolling mill and intermediate rolling mill for billet opening and rough and intermediate rolling. The final rolling temperature of rough rolling is controlled at 1000℃~1100℃. S3: Intermediate rolling and reheating: The intermediate billet after rough rolling is sent to the intermediate rolling mill for intermediate rolling; S4: Head cutting and pre-finishing: Flying shears are set at the exit of the first, second or third intermediate rolling mill for head cutting, and then the mill enters the pre-finishing mill for pre-finishing. S5: Finishing and sizing: The pre-finished rolled piece is sent to the finishing mill for finishing rolling, and then enters the sizing mill for sizing rolling. The finishing rolling temperature is controlled at 850℃~950℃. S6: Air cooling and coiling: The finished wire rod enters the wire drawing machine to form coils. The cooled coils are collected by the coil transport system to form large coils.

[0035] Compared with related technologies, the high-speed wire rod rolling production method of GH4169 wire rod provided by the present invention has the following beneficial effects: This invention provides a method for producing high-speed wire rod from GH4169 wire rod. By adopting a multi-stage temperature-controlled rolling process including billet opening, roughing and intermediate rolling, pre-finishing rolling, finishing rolling, and sizing reduction, combined with flying shear head and water cooling, the method effectively solves the problems of head-to-tail temperature difference and surface cooling in the rolling process of GH4169 alloy, ensuring stable finishing rolling temperature and facilitating the acquisition of uniform and fine grain structure. By optimizing the heating regime, rolling pass allocation, and overall temperature control, combined with the continuous heating capacity of the walking beam furnace and the high-efficiency rolling capacity of the semi-continuous mill, the single coil weight has been significantly increased to over 500 kg, meeting the downstream users' demand for long lengths and continuous processing, and improving production efficiency and yield. By controlling the deformation amount and rolling temperature in stages, and coordinating with a water-cooling device for controlled cooling, the problem of internal heat accumulation and overheating caused by the poor thermal conductivity of GH4169 alloy is effectively solved, ensuring the mechanical properties and service reliability of the product. Example

[0036] Please refer to the following: Figure 2 Based on the first embodiment of this application providing a method for producing high-speed GH4169 wire rod, the second embodiment of this application proposes another method for producing high-speed GH4169 wire rod. The second embodiment is merely a preferred embodiment of the first embodiment, and the implementation of the second embodiment will not affect the separate implementation of the first embodiment.

[0037] Specifically, the difference in the high-speed wire rod rolling production method of GH4169 wire rod provided in the second embodiment of this application is that, in step S4, a temperature measuring device is set up 0.5m to 1.5m before the entrance of the pre-finishing mill to continuously scan the temperature field of the entire length of the rolled piece and obtain the surface temperature distribution data of the head, middle and tail sections in real time. When it is detected that the temperature of the head and tail sections is more than 15°C lower than that of the middle section, the induction heating device is activated to perform dynamic heating.

[0038] The induction heating device performs dynamic heating, raising the heating temperature at the beginning and end of the mill by 15°C to 30°C compared to the middle section. The goal is to control the temperature difference of the rolled piece along its entire length at the entrance of the finishing mill within ±15°C. After dynamic heating is completed, the temperature is verified by a secondary temperature measuring device installed at the entrance of the finishing mill, forming a closed-loop control. Through the coordinated control of dynamic temperature measurement and closed-loop heating, the temperature of the rolled piece tends to be consistent when the steel is bitten by each stand of the finishing mill. This avoids sudden changes in deformation resistance and uneven microstructure caused by temperature fluctuations, and significantly improves the microstructure consistency and performance stability of the entire length of the wire rod.

[0039] In step S5, a rapid air mist cooling device is added between the last stand of the finishing mill and the sizing mill to cool the surface of the rolled piece.

[0040] The cooling rate of the aerosol cooling device is 3℃ / s to 8℃ / s. By adjusting the water-air ratio and the injection pressure, the temperature difference between the core and surface of the rolled piece is controlled to be ≤50℃.

[0041] The aerosol cooling device cools the surface of the rolled piece, thereby suppressing the accumulation of heat in the core and the degradation of overheated structure caused by low thermal conductivity.

[0042] During the large deformation process of finishing rolling, the deformation heat of the core is difficult to be discharged quickly, which can easily lead to excessive instantaneous temperature rise in the core, causing the γ″ strengthening phase to dissolve or coarsen. By using air mist cooling to force the surface to cool down, the temperature difference between the core and the surface forms a heat conduction driving force from the inside to the outside, which accelerates the heat discharge of the core and keeps the peak temperature of the core below the dissolution temperature of the γ″ phase. This effectively avoids the formation of overheated core structure and ensures the uniform precipitation of strengthening phase across the entire cross section of the wire rod. At the same time, rapid surface cooling refines the recrystallized austenite grains on the surface, forming a fine-grained strengthening layer, while avoiding grain boundary oxidation and dechromium removal, thus improving the surface quality and fatigue resistance of the wire rod. Furthermore, by controlling the cooling rate, the temperature of the rolled piece is precisely adjusted to the optimal inlet temperature range (850℃~900℃) of the sizing mill, ensuring that the sizing rolling is completed in the stable two-phase region, which is beneficial to obtaining a uniform and fine final grain structure.

[0043] Compared with related technologies, the high-speed wire rod rolling production method of GH4169 wire rod provided by the present invention has the following beneficial effects: This invention provides a method for producing high-speed wire rod from GH4169 wire rod. By continuously scanning the temperature field along the entire length of the rolled piece with a temperature measuring device, the induction heating device can perform dynamic heating, thereby increasing the stability of the head-to-tail temperature difference and surface temperature during the GH4169 alloy rolling process.

[0044] The above description is merely an embodiment of the present invention and does not limit the patent scope of the present invention. Any equivalent structural or procedural transformations made based on the content of the present invention specification and drawings, or direct or indirect applications in other related technical fields, are similarly included within the patent protection scope of the present invention.

Claims

1. A method for producing high-speed wire rod from GH4169 wire rod, characterized in that, Includes the following steps: S1: Billet preparation and heating: Select GH4169 alloy billet, place it in a walking beam furnace or chamber furnace and heat it to 1110℃~1125℃, hold it for 2~5 hours; S2: Rough rolling: The heated billet is sent to the primary rolling mill and intermediate rolling mill for billet opening and rough and intermediate rolling. The final rolling temperature of rough rolling is controlled at 1000℃~1100℃. S3: Intermediate rolling and reheating: The intermediate billet after rough rolling is sent to the intermediate rolling mill for intermediate rolling; S4: Head cutting and pre-finishing: Flying shears are set at the exit of the first, second or third intermediate rolling mill for head cutting, and then the mill enters the pre-finishing mill for pre-finishing. S5: Finishing and sizing: The pre-finished rolled piece is sent to the finishing mill for finishing rolling, and then enters the sizing mill for sizing rolling. The finishing rolling temperature is controlled at 850℃~950℃. S6: Air cooling and coiling: The finished wire rod enters the wire drawing machine to form coils. The cooled coils are collected by the coil transport system to form large coils.

2. The method for producing high-speed wire rod from GH4169 wire rod according to claim 1, characterized in that, The cross-sectional dimensions of the GH4169 alloy billet in step S1 are (100~120) mm × (100~120) mm square billet or equivalent cross-sectional round billet.

3. The method for producing high-speed wire rod from GH4169 wire rod according to claim 1, characterized in that, The total deformation of the billet during roughing and intermediate rolling in step S2 is 60% to 85%.

4. The method for producing high-speed wire rod from GH4169 wire rod according to claim 3, characterized in that, In step S2, the total deformation of the intermediate rolling mill is 50% to 70%, and an induction heating device is installed before the outlet of the intermediate rolling mill to quickly heat the rolled workpiece at a temperature of 1000℃ to 1050℃.

5. The method for producing high-speed wire rod from GH4169 wire rod according to claim 1, characterized in that, In step S3, the length of the cut head is 50-100mm, and the total deformation of the pre-finish rolling is 30%-50%.

6. The method for producing high-speed wire rod from GH4169 wire rod according to claim 1, characterized in that, In step S5, both the finishing mill and the sizing mill are equipped with shears at their inlets.

7. The method for producing high-speed wire rod from GH4169 wire rod according to claim 6, characterized in that, In step S5, the total deformation of finishing rolling and sizing is 30% to 60%.

8. The method for producing high-speed wire rod from GH4169 wire rod according to claim 4, characterized in that, In step S4, a temperature measuring device is set up 0.5m to 1.5m before the entrance of the pre-finishing mill to continuously scan the temperature field of the entire length of the rolled piece and obtain the surface temperature distribution data of the head, middle and tail sections in real time. When the temperature of the head and tail sections is detected to be more than 15°C lower than that of the middle section, the induction heating device is activated to perform dynamic heating.

9. A method for producing high-speed wire rod from GH4169 wire rod according to claim 7, characterized in that, In step S5, a rapid air mist cooling device is added between the last stand of the finishing mill and the sizing mill to cool the surface of the rolled piece.

10. A method for producing high-speed wire rod from GH4169 wire rod according to claim 9, characterized in that, The cooling rate of the aerosol cooling device is 3℃ / s to 8℃ / s, so that the temperature difference between the core and surface of the rolled piece is controlled within ≤50℃.

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