A hot forming process for an ultra-thick-wall super duplex steel high-pressure tee

Abstract

This invention relates to the field of thermoforming and discloses a high-pressure thermoforming process for ultra-thick-walled super duplex steel tee fittings. A transfer pump is fixedly connected to the top of a processing box, a support base is fixedly connected to the bottom of the processing box, a side plate is fixedly connected to the top of the support base, a storage tank is fixedly connected to the left side of the side plate, an air inlet pipe is fixedly connected to the top of the storage tank, and the end of the air inlet pipe furthest from the storage tank is fixedly connected to the top of the transfer pump. A cooling assembly includes a telescopic rod, which is fixedly connected to the top of the inner wall of the processing box, and a covering cavity is fixedly connected to the bottom of the telescopic rod. By setting up the cooling assembly, while cooling, the covering cavity, being made of compressible rubber and forming a sealed covering space, effectively concentrates the cooling spray, improves the heat exchange efficiency of the outer surface cooling, ensures a uniform cooling rate across all areas of the steel pipe's outer surface, avoids localized thermal stress concentration caused by rapid localized cooling, and effectively suppresses the problems of outer surface deformation and cracking.

Description

Technical Field

[0001] This invention relates to the field of thermoforming, specifically to a thermoforming process for ultra-thick-walled super duplex steel high-pressure tee fittings. Background Technology

[0002] The hot forming process of ultra-thick-walled super duplex steel high-pressure tee refers to the complete manufacturing process of heating ultra-thick-walled super duplex steel billets to a suitable hot working temperature in the duplex region, forming them as a high-pressure tee structure by hot extrusion or hot stamping, and then performing solution treatment and rapid cooling to ensure that the material has a balanced duplex structure and that its mechanical properties and corrosion resistance meet the requirements of high-pressure working conditions.

[0003] Patent application CN201811438732.3 discloses a hot forming process for ultra-high strength steel automotive parts, including the following steps: the blank is placed in a medium-frequency induction furnace and heated; the stamping die is preheated, and the blank is placed in the die for stamping; the press holds the pressure until the part in the die cools to 180-200°C, and the press drives the upper die to move upward; the blank is removed and placed in room temperature to cool naturally to below 50°C; the blank is placed in an electrolyte for electrochemical deburring and descaling; carburizing and nitriding; and the blank is removed and post-processed to obtain the final automotive parts.

[0004] However, this patent also has the following shortcomings: when the current cold quenching process cools the duplex high-pressure steel pipe, it is easy to cause an imbalance in the ratio of the two phases on the surface and in the core of the steel pipe due to uneven cooling, resulting in inconsistent performance of the same part. In addition, it is difficult to guarantee the cooling rate of the ultra-thick-walled steel pipe. Rapid cooling is prone to deformation and cracking, while slow cooling is prone to precipitation of σ phase, resulting in poor uniformity of microstructure and performance. In order to address this situation, a hot forming process for ultra-thick-walled super duplex high-pressure tee is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a hot forming process for ultra-thick-walled super duplex steel high-pressure tees to solve the problems mentioned in the background art.

[0006] To solve the above-mentioned technical problems, the present invention provides the following technical solution: a hot forming process for ultra-thick-walled super duplex steel high-pressure tees, comprising the following steps: S1: Select a standard super duplex steel billet, and confirm that the billet is free of cracks, looseness, inclusions and other problems through ultrasonic testing. Clean the surface oxide scale by shot blasting or grinding, and cut the billet according to the unfolded dimensions of the tee to ensure uniform wall thickness after hot forming.

[0007] S2: Step heating is carried out using a ring-shaped heating furnace: low temperature preheating at 250~300℃, medium temperature uniform heating at 600~650℃, and rapid heating to the thermoforming temperature of 1150~1180℃.

[0008] S3: Hot stamping is used to form the pipe blank. The mold is preheated to 250-350℃, and the pipe blank is quickly placed into the mold cavity. The main pipe is pre-formed first, the branch pipe is extruded and formed, and finally the whole pipe is shaped.

[0009] S4: After forming, quickly transfer to the solution furnace without air cooling to room temperature. The solution temperature of the solution furnace is set to 1080~1120℃. The temperature is uniformly uniformly uniformly and then kept at a constant temperature to ensure that the core reaches the correct temperature.

[0010] S5: The solution-treated steel pipe is sent into the processing box. The steel pipe inside the processing box is subjected to controlled quenching by starting the transfer pump. The transfer pump is fixedly connected to the top of the processing box, and a support base is fixedly connected to the bottom of the processing box. A side plate is fixedly connected to the top of the support base, and a storage tank is fixedly connected to the left side of the side plate. An air inlet pipe is fixedly connected to the top of the storage tank. The end of the air inlet pipe away from the storage tank is fixedly connected to the top of the transfer pump. A cooling assembly is provided on the top of the inner wall of the processing box. The cooling assembly includes a telescopic rod, which is fixedly connected to the top of the inner wall of the processing box. A covering cavity is fixedly connected to the bottom of the telescopic rod. The coolant in the storage tank is pressurized by the transfer pump and delivered to the atomizing nozzle to form a cooling spray. The compressible covering cavity is used to seal and cover the outer surface of the steel pipe to achieve uniform spray cooling throughout the entire area. At the same time, the cooling assembly is extended into the inner cavity of the main and branch pipes of the steel pipe to achieve synchronous cooling inside and outside. Impact cooling is also performed on the contact surface between the bottom of the steel pipe and the tooling to eliminate cooling dead corners and quickly pass through the σ phase precipitation temperature zone.

[0011] According to the above technical solution, the cooling assembly further includes a jet plate, which is fixedly connected to the inner wall of the covering cavity. A clamping plate is rotatably connected to the inner wall of the covering cavity. When the telescopic rod moves the covering cavity to the surface of the steel pipe, the steel pipe surface squeezes the covering cavity, causing the inner wall of the covering cavity to be stressed and extend outward.

[0012] According to the above technical solution, the bottom of the jet disk is provided with a jet hole, the inner wall of the clamping disk is fixedly connected with a magnetic suction cup, the covering cavity is made of compressible rubber material, the surface of the covering cavity is provided with a partition groove, the inner wall of the processing box is fixedly connected with a displacement ring, the inner wall of the displacement ring is provided with a transmission mechanism, the bottom of the inner wall of the processing box is provided with a bottom punching mechanism, and the clamping disk at the bottom of the covering cavity will magnetically attract the surface of the steel pipe through the internal magnetic suction cup, thereby fixing the covering cavity to the surface of the steel pipe.

[0013] According to the above technical solution, the transmission mechanism includes a movable seat, which is slidably connected to the inner wall of the displacement ring. Adjusting arms are rotatably connected to both sides of the movable seat via rotating shafts. A mounting base is fixedly connected to the left side of the adjusting arm. A conveying pipe is fixedly connected to the inner wall of the mounting base. The end of the conveying pipe away from the mounting base is fixedly connected to the top of the inner wall of the processing box. A telescopic cavity is fixedly connected to the bottom of the adjusting arm. A cold quenching component is provided on the inner wall of the telescopic cavity. When the movable seat slides and approaches the surface of the steel pipe opening, the internal controller of the movable seat is activated to drive one end of the adjusting arm to rotate in the movable seat.

[0014] According to the above technical solution, the cold quenching assembly includes an elastic tube, one end of which is slidably connected to the inner wall of the telescopic cavity, and a support plate is fixedly connected to the end of the elastic tube away from the telescopic cavity. An elastic seat is fixedly connected to the inner wall of the support plate, and a telescopic pad is fixedly connected to the top of the elastic seat. A discharge ring is fixedly connected to the top of the telescopic pad. When the support plate slides inside the tube wall, the telescopic pad on the inner wall of the support plate will contract inward due to the pressure from the tube wall.

[0015] According to the above technical solution, the elastic tube has the function of stretching and elastically restoring, one end of the support plate is equipped with an air jet pipe, the inside of the conveying pipe is provided with a cavity, and the conveying pipe has tensile characteristics. When the elastic tube enters the inside of the steel pipe, the elastic tube can slide inside the curved pipe wall.

[0016] According to the above technical solution, the telescopic pad has compressibility elasticity, the telescopic pad has discharge grooves on both sides, and the discharge ring has a slot hole at the top. When the support plate slides inside the pipe wall, the telescopic pad on the inner wall of the support plate will contract inward due to the pressure of the pipe wall.

[0017] According to the above technical solution, the bottom-punching mechanism includes a pad, which is fixedly connected to the bottom of the inner wall of the processing box. A placement seat is fixedly connected to the top of the pad, and a contact plate is fixedly connected to the inner wall of the placement seat. A conveying rod is fixedly connected to the inner wall of the contact plate, and the end of the conveying rod away from the contact plate is fixedly connected to the inner wall of the placement seat. An impact plate is fixedly connected to the top of the conveying rod, and a feeding seat is fixedly connected to the top of the placement seat. A contact ring is fixedly connected to the inner wall of the feeding seat, and one end of the contact ring is fixedly connected to the top of the placement seat. A uniform component is provided on the top of the pad. When the cooling water mist sprayed by multiple spraying frames cools the surface of the steel pipe, the water mist will splash onto the surface of the contact ring while contacting the surface of the steel pipe.

[0018] According to the above technical solution, the uniform assembly includes a support frame, which is fixedly connected to the top of the pad. A spray gun is fixedly connected to the top of the support frame. A guide rod is fixedly connected to one end of the spray gun. The end of the guide rod away from the spray gun is fixedly connected to the bottom of the inner wall of the processing box. A conveyor plate is fixedly connected to the end of the spray gun away from the guide rod. Spray frames are rotatably connected to both sides of the conveyor plate. A guide ring is fixedly connected to the inner wall of the conveyor plate. The end of the guide ring away from the conveyor plate is fixedly connected to the inner wall of the spray frame. By starting an external drainage pump, cooling water is compressed into cooling water mist and transported into the spray gun through the guide rod.

[0019] According to the above technical solution, the bottom of the ejector frame is provided with an ejection hole, the contact ring is made of a rubber material with tensile strength, the inner wall of the contact ring is provided with a slot, and the top of the impact plate is provided with an ejection hole. By activating the internal controller of the ejector gun, the ejector frame is driven to rotate up and down on the inner wall of the conveyor plate.

[0020] Compared with the prior art, the beneficial effects of the present invention are: 1. This invention, through the setting of a transmission mechanism, allows the elastic tube to slide inside the curved pipe wall after entering the steel pipe. When the support plate slides inside the pipe wall, the telescopic pad on the inner wall of the support plate contracts inward due to the pressure from the pipe wall. At this time, cooling water is sprayed outward from one end of the support plate, and cooling water is also sprayed outward from both sides of the telescopic pad. While the discharge ring slides and contacts the pipe wall, the cooling water discharged through the discharge ring also cools the pipe wall. By setting this mechanism, the outer wall of the steel pipe, the inner hole of the main pipe, and the inner cavity of the branch pipe are cooled simultaneously in three ways, ensuring the cooling rate of the ultra-thick wall section and solving the problem of insufficient cooling rate in the core of the duplex steel pipe. 2. This invention, through the installation of a cooling assembly, utilizes an internal magnetic suction plate at the bottom of the covering cavity to magnetically attract the steel pipe surface, thus fixing the covering cavity to the steel pipe surface. Simultaneously, the jet nozzles of the jet nozzles uniformly spray cooling mist, providing comprehensive and uniform cooling to the outer surface of the steel pipe. While cooling, the covering cavity, made of compressible rubber and forming a sealed covering space, effectively concentrates the cooling mist, improving the heat exchange efficiency of the outer surface cooling. This ensures consistent cooling rates across all areas of the steel pipe's outer surface, avoiding localized thermal stress concentration caused by rapid localized cooling, and effectively suppressing outer surface deformation and cracking. 3. This invention, by setting up a bottom-impact mechanism, uses an absorption pump inside the feed seat to transport cooling water mist splashed into the grooves of the contact ring into the internal cavity of the placement seat. The cooling water mist is then discharged into the impact plate via a conveying rod. Finally, the cooling water mist is ejected through the top nozzle of the impact plate to impact the contact surface between the bottom of the steel pipe and the contact plate. This effectively solves the problem of the cooling dead zone between the bottom of the steel pipe and the tooling contact surface, and avoids the situation where insufficient cooling speed in this area leads to slow cooling and precipitation of the σ phase.

[0021] 4. This invention, by setting up uniform components and activating the internal controller of the spray gun, drives the spray frame to rotate up and down on the inner wall of the conveyor plate. This allows the cooling water mist to cover the main and branch pipes of the ultra-thick-walled tee from multiple angles, completely eliminating cooling blind spots in irregularly shaped parts in traditional cooling methods. This effectively reduces thermal and structural stress in irregularly shaped parts, preventing deformation and cracking in stress-sensitive areas such as intersection zones. Attached Figure Description Figure 1 This is a schematic diagram of the overall structure of the present invention; Figure 2 This is a schematic diagram of the internal cross-sectional structure of the processing box of the present invention; Figure 3 This is a perspective view of the cooling assembly of the present invention; Figure 4 This is a perspective view of the transmission mechanism of the present invention; Figure 5 This is a cross-sectional view of the cold quenching component of the present invention; Figure 6 This is a perspective view of the bottom-punching mechanism of the present invention; Figure 7 This is a partial schematic diagram of the contact plate of the present invention; Figure 8 This is a perspective view of the uniform component of the present invention.

[0022] In the diagram: 1. Support base; 2. Machining box; 3. Side plate; 4. Storage tank; 5. Air inlet pipe; 6. Transfer pump; 7. Transfer mechanism; 701. Movable seat; 702. Adjusting arm; 703. Mounting base; 704. Conveying pipe; 705. Telescopic cavity; 706. Cold quenching assembly; 7061. Elastic tube; 7062. Support plate; 7063. Elastic seat; 7064. Telescopic pad; 7065. Discharge ring; 8. Cooling assembly; 801. Telescopic rod; 8 02. Covering cavity; 803. Jet plate; 804. Clamping plate; 9. Bottom punching mechanism; 901. Pad; 902. Placement seat; 903. Contact plate; 904. Conveyor rod; 905. Impact plate; 906. Feed seat; 907. Contact ring; 908. Uniform assembly; 9081. Support frame; 9082. Spray gun; 9083. Feed rod; 9084. Conveyor plate; 9085. Spray frame; 9086. Guide ring; 10. Displacement ring. Detailed Implementation

[0023] The technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments.

[0024] Examples of the embodiments are shown in the accompanying drawings, wherein the same or similar reference numerals denote the same or similar elements or elements having the same or similar functions throughout. The embodiments described below with reference to the accompanying drawings are exemplary and intended to explain the invention, and should not be construed as limiting the invention.

[0025] In this invention, unless otherwise explicitly specified and limited, the terms "installation," "connection," "linking," and "fixing," etc., should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral part; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium; they can refer to the internal communication of two components or the interaction between two components. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0026] Example 1: See Figures 1-3 The present invention provides a technical solution: a high-pressure hot forming process for ultra-thick-walled super duplex steel tees, comprising the following steps: S1: Select a standard super duplex steel billet, and confirm that the billet is free of cracks, looseness, inclusions and other problems through ultrasonic testing. Clean the surface oxide scale by shot blasting or grinding, and cut the billet according to the unfolded dimensions of the tee to ensure uniform wall thickness after hot forming.

[0027] S2: Step heating is carried out using a ring-shaped heating furnace: low temperature preheating at 250~300℃, medium temperature uniform heating at 600~650℃, and rapid heating to the thermoforming temperature of 1150~1180℃.

[0028] S3: Hot stamping is used to form the pipe blank. The mold is preheated to 250-350℃, and the pipe blank is quickly placed into the mold cavity. The main pipe is pre-formed first, the branch pipe is extruded and formed, and finally the whole pipe is shaped.

[0029] S4: After forming, quickly transfer to the solution furnace without air cooling to room temperature. The solution temperature of the solution furnace is set to 1080~1120℃. The temperature is uniformly uniformly uniformly and then kept at a constant temperature to ensure that the core reaches the correct temperature.

[0030] S5: The solution-treated steel pipe is fed into the processing box 2. The transfer pump 6 is started to perform controlled quenching treatment on the steel pipe inside the processing box 2. The transfer pump 6 is fixedly connected to the top of the processing box 2. A support base 1 is fixedly connected to the bottom of the processing box 2. A side plate 3 is fixedly connected to the top of the support base 1. A storage tank 4 is fixedly connected to the left side of the side plate 3. An air inlet pipe 5 is fixedly connected to the top of the storage tank 4. The end of the air inlet pipe 5 away from the storage tank 4 is fixedly connected to the top of the transfer pump 6. A cooling assembly 8 is installed on the top of the inner wall of the processing box 2. The cooling assembly 8 includes... The system includes a telescopic rod 801, which is fixedly connected to the top of the inner wall of the processing box 2. The bottom of the telescopic rod 801 is fixedly connected to a covering cavity 802. The coolant in the storage tank 4 is pressurized by the transfer pump 6 and delivered to the atomizing nozzle to form a cooling spray. The compressible covering cavity 802 is used to seal and cover the outer surface of the steel pipe, achieving uniform spray cooling throughout the entire area. At the same time, the cooling component 8 is extended into the inner cavity of the main and branch pipes of the steel pipe to achieve synchronous cooling inside and outside. The bottom of the steel pipe and the contact surface with the tooling are subjected to impact cooling to eliminate cooling dead corners and quickly pass through the σ phase precipitation temperature zone.

[0031] Example 2: Based on Example 1, please refer to the following... Figures 1-3 The present invention provides a technical solution: the cooling assembly 8 further includes a jet disc 803, which is fixedly connected to the inner wall of the covering cavity 802. A clamping disc 804 is rotatably connected to the inner wall of the covering cavity 802. When the transfer pump 6 is started to pressurize, the coolant in the storage tank 4 is transported to the atomizing nozzle of the jet disc 803 through the air inlet pipe 5 to form a cooling spray. The cooling spray inside the storage tank 4 is then absorbed by the transfer pump 6 through the air inlet pipe 5 and discharged into the telescopic rod 801. Then, by starting the telescopic switch inside the telescopic rod 801, the telescopic rod 801 is driven to slide downward and extend. When the telescopic rod 801 moves the covering cavity 802 to the surface of the steel pipe, the steel pipe surface squeezes the covering cavity 802, causing the inner wall of the covering cavity 802 to be stressed and extend outward, thereby fully covering the steel pipe.

[0032] The ultra-thick-walled super duplex steel high-pressure tee has an irregular structure with different curved surfaces on the outer surface of the main pipe, branch pipe and intersecting area. Traditional cold quenching process is prone to uneven cooling of its outer surface, resulting in large differences in cooling rate in different areas of the outer surface. This can easily cause local thermal stress concentration, resulting in deformation and cracking. In addition, the uneven cooling efficiency of the outer surface will affect the overall cooling rhythm and make it impossible to quickly pass through the high-risk temperature zone of σ phase precipitation. Therefore, a cooling component 8 is required.

[0033] The bottom of the jet disk 803 has jet holes, and the inner wall of the clamping disk 804 is fixedly connected to a magnetic chuck. The covering cavity 802 is made of compressible rubber material, and the surface of the covering cavity 802 has dividing grooves. The inner wall of the processing box 2 is fixedly connected to a displacement ring 10, and the inner wall of the displacement ring 10 is provided with a transmission mechanism 7. The bottom of the inner wall of the processing box 2 is provided with a bottom-punching mechanism 9. At the same time, the clamping disk 804 at the bottom of the covering cavity 802 magnetically attracts the surface of the steel pipe through the internal magnetic chuck, thereby fixing the covering cavity 802 to the surface of the steel pipe. At this time, the jet holes of the jet disk 803 uniformly spray cooling spray to comprehensively and uniformly cool the outer surface of the steel pipe. While cooling, because the covering cavity 802 is made of compressible rubber material and forms a sealed covering space, it can effectively concentrate the cooling spray, improve the heat exchange efficiency of the outer surface cooling, ensure that the cooling rate of each area of ​​the outer surface of the steel pipe is consistent, avoid local thermal stress concentration caused by rapid local cooling, and effectively suppress the problem of outer surface deformation and cracking.

[0034] Example 3: Based on Example 2, please refer to the following... Figures 4-5 The present invention provides a technical solution: the transmission mechanism 7 includes a movable seat 701, which is slidably connected to the inner wall of the displacement ring 10. Adjusting arms 702 are rotatably connected to both sides of the movable seat 701 via rotating shafts. A mounting base 703 is fixedly connected to the left side of the adjusting arm 702. A conveying pipe 704 is fixedly connected to the inner wall of the mounting base 703. One end of the conveying pipe 704 away from the mounting base 703 is fixedly connected to the top of the inner wall of the processing box 2. A telescopic cavity 705 is fixedly connected to the bottom of the adjusting arm 702. The inner wall is equipped with a cold quenching component 706. After the solution-treated steel pipe is put into the processing box 2, the sliding device inside the displacement ring 10 is activated to drive the movable seat 701 to slide inside the displacement ring 10. When the movable seat 701 drives the adjusting arm 702 to rotate around the steel pipe, when the movable seat 701 slides and approaches the pipe opening surface, the controller inside the movable seat 701 is activated to drive one end of the adjusting arm 702 to rotate in the movable seat 701. The adjusting arm 702 drives one end of the telescopic cavity 705 to align with the pipe opening.

[0035] The cold quenching assembly 706 includes an elastic tube 7061. One end of the elastic tube 7061 is slidably connected to the inner wall of the telescopic cavity 705. The end of the elastic tube 7061 away from the telescopic cavity 705 is fixedly connected to a support plate 7062. An elastic seat 7063 is fixedly connected to the inner wall of the support plate 7062. A telescopic pad 7064 is fixedly connected to the top of the elastic seat 7063. A discharge ring 7065 is fixedly connected to the top of the telescopic pad 7064. The controller drives the elastic tube 7061 to slide and extend outward. When the elastic tube 7061 extends and extends into the steel pipe through the pipe opening, cooling water is then transported into the mounting base 703 through the pipe opening at the top of the processing box 2 via the conveying pipe 704. The cooling water is then transported into the elastic tube 7061 through the mounting base 703. Because the elastic tube 7061 has an elastic extension and contraction function, when the elastic tube 7061 enters the steel pipe, it can slide inside the curved pipe wall.

[0036] Current cold quenching processes only cool the outer surface of ultra-thick-walled super duplex steel high-pressure tees, leaving the internal structures, such as the main pipe bore and branch pipe cavities, as weak areas for cooling. This results in a significant difference in cooling rates between the surface and the core of the ultra-thick-walled section. Not only is the core cooling rate insufficient, making it prone to σ-phase precipitation, but the uneven cooling rates between the surface and the core also cause an imbalance in the duplex phase ratio and inconsistent performance of the same part. Therefore, it is necessary to set up a cold quenching assembly 706.

[0037] The elastic tube 7061 has the function of stretching and elastically restoring. One end of the support plate 7062 is equipped with a jet pipe. The inside of the delivery pipe 704 is provided with a cavity. The delivery pipe 704 has tensile characteristics. When the support plate 7062 slides inside the pipe wall, the telescopic pad 7064 on the inner wall of the support plate 7062 will contract inward due to the pressure of the pipe wall. At this time, cooling water is sprayed outward through one end of the support plate 7062, and cooling water is also sprayed outward from both sides of the telescopic pad 7064.

[0038] The expansion pad 7064 has compressibility and elasticity. Discharge grooves are opened on both sides of the expansion pad 7064, and a slot is opened on the top of the discharge ring 7065. While the discharge ring 7065 is in sliding contact with the pipe wall, the cooling water discharged through the discharge ring 7065 will also cool the pipe wall of the steel pipe. By simultaneously cooling the outer wall of the steel pipe, the inner hole of the main pipe, and the inner cavity of the branch pipe in three ways, the cooling rate of the ultra-thick wall section is guaranteed, and the problem of insufficient cooling rate of the core of the duplex steel pipe is solved.

[0039] Example 4: Based on Example 3, please refer to the following... Figures 6-8The present invention provides a technical solution: the bottom punching mechanism 9 includes a pad 901, which is fixedly connected to the bottom of the inner wall of the processing box 2. A placement seat 902 is fixedly connected to the top of the pad 901. A contact plate 903 is fixedly connected to the inner wall of the placement seat 902. A conveying rod 904 is fixedly connected to the inner wall of the contact plate 903. One end of the conveying rod 904 away from the contact plate 903 is fixedly connected to the inner wall of the placement seat 902. The formed three-way steel pipe is placed on the top of the contact plate 903. When the cooling water mist sprayed by multiple spraying frames 9085 cools the surface of the steel pipe, the water mist will splash onto the surface of the contact ring 907 while contacting the surface of the steel pipe. By starting the absorption pump inside the feed seat 906, the cooling water mist splashed into the groove of the inner wall of the contact ring 907 is transported into the internal cavity of the placement seat 902.

[0040] An impact plate 905 is fixedly connected to the top of the conveying rod 904, and a feeding seat 906 is fixedly connected to the top of the placement seat 902. A contact ring 907 is fixedly connected to the inner wall of the feeding seat 906. One end of the contact ring 907 is fixedly connected to the top of the placement seat 902. A uniform component 908 is provided on the top of the pad 901. Cooling water mist is discharged into the impact plate 905 through the conveying rod 904. Finally, the cooling water mist is ejected through the top nozzle of the impact plate 905 to impact the contact surface between the bottom of the steel pipe and the contact plate 903. This effectively solves the problem of the cooling dead angle between the bottom of the steel pipe and the contact surface of the tooling, and avoids the situation where the cooling rate is insufficient due to the lag in cooling in this area, resulting in slow cooling and precipitation of the σ phase.

[0041] The uniform assembly 908 includes a support frame 9081, which is fixedly connected to the top of the pad 901. A spray gun 9082 is fixedly connected to the top of the support frame 9081. A guide rod 9083 is fixedly connected to one end of the spray gun 9082. The end of the guide rod 9083 away from the spray gun 9082 is fixedly connected to the bottom of the inner wall of the processing box 2. A conveyor plate 9084 is fixedly connected to the end of the spray gun 9082 away from the guide rod 9083. Spray frames 9085 are rotatably connected to both sides of the conveyor plate 9084. A guide ring 9086 is fixedly connected to the inner wall of the conveyor plate 9084. The end furthest from the conveyor plate 9084 is fixedly connected to the inner wall of the spray frame 9085. By starting the external drainage pump, the cooling water is compressed into cooling water mist and conveyed into the spray gun 9082 through the feed rod 9083. The cooling water mist is discharged into the guide ring 9086 through the conveyor plate 9084 on the inner wall of the spray chamber. The guide ring 9086 then conveys the cooling water mist into the spray frame 9085. At this time, by starting the internal controller of the spray gun 9082, the spray frame 9085 is driven to rotate up and down on the inner wall of the conveyor plate 9084, so that the cooling water mist can cover the main pipe and branch pipe of the ultra-thick wall tee from multiple angles.

[0042] When ultra-thick-walled super duplex steel high-pressure tees are cooled, the bottom of the tee comes into contact with the tooling, forming a closed contact surface. This becomes a cooling dead zone in the traditional cold quenching process. This area cannot be effectively cooled, resulting in a serious lag in the cooling rate. Not only is it easy for σ phase to precipitate, but it also forms large structural stress with other parts of the pipe, which in turn causes cracking and deformation problems. Therefore, it is necessary to set up a bottom punching mechanism 9.

[0043] The bottom of the ejector frame 9085 has an ejection hole, and the contact ring 907 is made of stretch-resistant rubber material with slots on its inner wall. The top of the impact plate 905 has an ejection hole, completely eliminating the cooling blind spots in irregularly shaped parts in traditional cooling. The gentle cooling form of the cooling water mist ensures that the cooling rate of each part is stable and meets the process requirements, can quickly pass through the high-risk temperature zone of σ phase precipitation, and prevents the precipitation of brittle phase. It also avoids the problem of sudden local cooling rate caused by direct-spray cooling water, effectively reducing the thermal stress and structural stress of irregularly shaped parts, and preventing deformation and cracking in stress-sensitive parts such as intersecting areas.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such process, method, article, or apparatus.

[0045] Finally, it should be noted that the above descriptions are merely preferred embodiments of the present invention and are not intended to limit the present invention. Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A hot forming process for ultra-thick-walled super duplex steel high-pressure tees, characterized in that: Includes the following steps: S1: Select a super duplex steel billet that meets the standard, and confirm that the billet is free of cracks, looseness and inclusions through ultrasonic testing. Clean the surface oxide scale by shot blasting or grinding, and cut the billet according to the unfolded dimensions of the tee to ensure uniform wall thickness after hot forming. S2: Step heating is carried out using a ring heating furnace: low temperature preheating at 250~300℃, medium temperature uniform heating at 600~650℃, and rapid heating to the thermoforming temperature of 1150~1180℃; S3: Hot stamping is used to form the pipe blank. The mold is preheated to 250-350°C. The pipe blank is quickly placed into the mold cavity. The main pipe is pre-formed first, the branch pipe is extruded and formed, and finally the whole pipe is shaped. S4: After forming, quickly transfer to the solution furnace without air cooling to room temperature. The solution temperature of the solution furnace is set to 1080~1120℃. The temperature is uniformly uniformly uniformly and then kept at a constant temperature to ensure that the core reaches the correct temperature. S5: The solution-treated steel pipe is sent into the processing box (2). The steel pipe inside the processing box is subjected to controlled quenching by starting the transfer pump (6). The transfer pump (6) is fixedly connected to the top of the processing box (2). A support base (1) is fixedly connected to the bottom of the processing box (2). A side plate (3) is fixedly connected to the top of the support base (1). A storage tank (4) is fixedly connected to the left side of the side plate (3). An air inlet pipe (5) is fixedly connected to the top of the storage tank (4). The end of the air inlet pipe (5) away from the storage tank (4) is fixedly connected to the top of the transfer pump (6). A cooling assembly is provided on the top of the inner wall of the processing box (2). (8) The cooling component (8) includes a telescopic rod (801), which is fixedly connected to the top of the inner wall of the processing box (2). The bottom of the telescopic rod (801) is fixedly connected to a covering cavity (802). The coolant in the storage tank (4) is pressurized by the transfer pump (6) and transported to the atomizing nozzle to form a cooling spray. The compressible covering cavity (802) is used to seal and cover the outer surface of the steel pipe to achieve uniform spray cooling throughout the entire area. At the same time, the cooling component (8) is inserted into the inner cavity of the main pipe and the branch pipe of the steel pipe to achieve synchronous cooling inside and outside. The bottom of the steel pipe and the contact surface of the tooling are impacted and cooled to eliminate the cooling dead angle and quickly pass through the σ phase precipitation temperature zone.

2. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 1, characterized in that: The cooling assembly (8) further includes a jet disk (803), which is fixedly connected to the inner wall of the covering cavity (802). A clamping disk (804) is rotatably connected to the inner wall of the covering cavity (802), and the clamping disk (804) is used to clamp the steel pipe.

3. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 2, characterized in that: The bottom of the jet disk (803) is provided with jet holes, the inner wall of the clamping disk (804) is fixedly connected with a magnetic suction disk, the covering cavity (802) is made of compressible rubber material, the surface of the covering cavity (802) is provided with a partition groove, the inner wall of the processing box (2) is fixedly connected with a displacement ring (10), the inner wall of the displacement ring (10) is provided with a transmission mechanism (7), the bottom of the inner wall of the processing box (2) is provided with a punching mechanism (9), and the covering cavity (802) is used to cover the surface of the steel pipe.

4. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 3, characterized in that: The transmission mechanism (7) includes a movable seat (701), which is slidably connected to the inner wall of the displacement ring (10). Adjusting arms (702) are rotatably connected to both sides of the movable seat (701) via a rotating shaft. A mounting base (703) is fixedly connected to the left side of the adjusting arm (702). A conveying pipe (704) is fixedly connected to the inner wall of the mounting base (703). One end of the conveying pipe (704) away from the mounting base (703) is fixedly connected to the top of the inner wall of the processing box (2). A telescopic cavity (705) is fixedly connected to the bottom of the adjusting arm (702). A cold quenching component (706) is provided on the inner wall of the telescopic cavity (705). The adjusting arm (702) is used to rotate on both sides of the mounting base (703).

5. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 4, characterized in that: The quenching assembly (706) includes an elastic tube (7061), one end of which is slidably connected to the inner wall of the telescopic cavity (705). A support plate (7062) is fixedly connected to the end of the elastic tube (7061) away from the telescopic cavity (705). An elastic seat (7063) is fixedly connected to the inner wall of the support plate (7062). A telescopic pad (7064) is fixedly connected to the top of the elastic seat (7063). A discharge ring (7065) is fixedly connected to the top of the telescopic pad (7064). The elastic tube (7061) is used to slide and extend within the inner wall of the telescopic cavity (705).

6. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 5, characterized in that: The elastic tube (7061) has the function of stretching and elastically restoring, one end of the support plate (7062) is equipped with a jet pipe, the inside of the delivery pipe (704) is provided with a cavity, the delivery pipe (704) has tensile characteristics, and the support plate (7062) is used to spray cooling water to the outside.

7. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 5, characterized in that: The telescopic pad (7064) has compressibility elasticity, and discharge grooves are provided on both sides of the telescopic pad (7064). The top of the discharge ring (7065) is provided with a slot, and the discharge ring (7065) is used to spray cooling water onto the inner wall of the steel pipe.

8. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 3, characterized in that: The bottom-punching mechanism (9) includes a pad (901), which is fixedly connected to the bottom of the inner wall of the processing box (2). A placement seat (902) is fixedly connected to the top of the pad (901). A contact plate (903) is fixedly connected to the inner wall of the placement seat (902). A conveying rod (904) is fixedly connected to the inner wall of the contact plate (903). One end of the conveying rod (904) away from the contact plate (903) is fixed to the inner wall of the placement seat (902). The top of the conveying rod (904) is fixedly connected to an impact plate (905), the top of the placement seat (902) is fixedly connected to a feed seat (906), the inner wall of the feed seat (906) is fixedly connected to a contact ring (907), one end of the contact ring (907) is fixedly connected to the top of the placement seat (902), the top of the pad (901) is provided with a uniform component (908), and the impact plate (905) is used to cool the bottom of the steel pipe.

9. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 8, characterized in that: The uniform assembly (908) includes a support frame (9081), which is fixedly connected to the top of the pad (901). A spray gun (9082) is fixedly connected to the top of the support frame (9081). One end of the spray gun (9082) is fixedly connected to a feed rod (9083). The end of the feed rod (9083) away from the spray gun (9082) is fixedly connected to the bottom of the inner wall of the processing box (2). 82) A conveyor plate (9084) is fixedly connected to one end away from the feed rod (9083). A spraying frame (9085) is rotatably connected to both sides of the conveyor plate (9084). A guide ring (9086) is fixedly connected to the inner wall of the conveyor plate (9084). The end of the guide ring (9086) away from the conveyor plate (9084) is fixedly connected to the inner wall of the spraying frame (9085). The spraying gun (9082) is used to cool the surface of the steel pipe.

10. The hot forming process for ultra-thick-walled super duplex steel high-pressure tees according to claim 9, characterized in that: The bottom of the ejector frame (9085) is provided with an ejection hole, the contact ring (907) is made of a rubber material with stretch resistance, the inner wall of the contact ring (907) is provided with a slot, the top of the impact plate (905) is provided with an ejection hole, and the contact ring (907) is used to absorb cooling water.

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