WO2024093182A1 - Method and device for improving hardness of reaustenitizing area of hypereutectoid steel rail joint - Google Patents

Method and device for improving hardness of reaustenitizing area of hypereutectoid steel rail joint Download PDF

Info

Publication number
WO2024093182A1
WO2024093182A1 PCT/CN2023/093531 CN2023093531W WO2024093182A1 WO 2024093182 A1 WO2024093182 A1 WO 2024093182A1 CN 2023093531 W CN2023093531 W CN 2023093531W WO 2024093182 A1 WO2024093182 A1 WO 2024093182A1
Authority
WO
WIPO (PCT)
Prior art keywords
rail
hardness
hypereutectoid
flash
joint
Prior art date
Application number
PCT/CN2023/093531
Other languages
French (fr)
Chinese (zh)
Inventor
陆鑫
李大东
邓健
董雪娇
Original Assignee
攀钢集团攀枝花钢铁研究院有限公司
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by 攀钢集团攀枝花钢铁研究院有限公司 filed Critical 攀钢集团攀枝花钢铁研究院有限公司
Priority to AU2023216732A priority Critical patent/AU2023216732A1/en
Publication of WO2024093182A1 publication Critical patent/WO2024093182A1/en

Links

Classifications

    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/18—Hardening; Quenching with or without subsequent tempering
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
    • C21D1/62—Quenching devices
    • C—CHEMISTRY; METALLURGY
    • C21—METALLURGY OF IRON
    • C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
    • C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
    • C21D9/50—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for welded joints
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/02—Ferrous alloys, e.g. steel alloys containing silicon
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/04—Ferrous alloys, e.g. steel alloys containing manganese
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/12—Ferrous alloys, e.g. steel alloys containing tungsten, tantalum, molybdenum, vanadium, or niobium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C38/00—Ferrous alloys, e.g. steel alloys
    • C22C38/18—Ferrous alloys, e.g. steel alloys containing chromium
    • C22C38/24—Ferrous alloys, e.g. steel alloys containing chromium with vanadium

Definitions

  • the invention relates to the technical field of rail welding, and in particular to a method and a device for improving the hardness of a re-austenitizing zone of a hypereutectoid rail joint.
  • rails with a carbon content of more than 0.90% are usually called hypereutectoid rails.
  • Technicians increase the thickness of cementite sheets and cementite density in the matrix to improve the hardness and wear resistance of the rails, that is, increase the carbon content to obtain higher hardness.
  • the higher the strength and hardness of the rails the worse the welding performance of the rails.
  • the welded joints are the weak link in the railway lines. Therefore, the optimization of the performance of heavy-load rail welded joints is also a focus of research by scholars at home and abroad.
  • the re-austenitizing zone of rail flash welding refers to the area in the rail joint where austenite phase transformation occurs during the welding heating process. Because the phase transformation law during heating and cooling is the same as the heat treatment normalizing process, this area is also usually called the normalizing zone. Under normal circumstances, the microstructure, tensile and impact properties of the re-austenitizing zone of rail flash welding are better than those of the base material. However, the hardness index of the re-austenitizing zone of the flash welded joint of rails with different chemical compositions and supply conditions will be different from that of the base material. Generally speaking, the hardness of the rail is mainly determined by the cooling rate.
  • the greater the cooling rate during the cooling process the higher the hardness. If the cooling rate of the re-austenitizing zone after welding is greater than the cooling rate of the base material, the hardness of the re-austenitizing zone will be higher than that of the base material; if the cooling rate of the re-austenitizing zone after welding is less than the cooling rate of the base material, the hardness of the re-austenitizing zone will be lower than that of the base material.
  • the hardness of the re-austenitizing zone is too high or too low, which will affect the smoothness of the joint during service, and abnormal harmful structures such as martensite and bainite will also affect the performance of the rail joint.
  • the purpose of the embodiments of the present invention is to propose a method and device for improving the hardness of the re-austenization zone of a hypereutectoid rail joint, by controlling welding parameters and post-weld cooling treatment to improve the hardness of the re-austenization zone of a high-strength hypereutectoid rail joint for heavy-duty railways, thereby effectively ensuring the smoothness of the rail joint.
  • an embodiment of the present invention provides a method for improving the hardness of a hypereutectoid rail joint re-austenitization zone, the method comprising:
  • each processing step is connected by a conveying roller to form a production line, and the hypereutectoid rail joint is driven by the conveying roller to enter each processing step in turn.
  • the quenching length during the circumferential quenching treatment is 10 to 50 meters.
  • the welding process of step (2) includes:
  • the high-voltage time in the pre-flash stage is 45s to 65s, and the flash speed is 0.1mm/s to 0.6mm/s;
  • the low pressure time in the flash stage is 80s to 140s, and the flash speed is 0.1mm/s to 0.6mm/s;
  • the flash acceleration speed in the accelerated burning stage is 0.5mm/s to 2.0mm/s;
  • the live forging time in the forging stage is 0.1s to 2.0s, and the forging timing is 1.0s to 3.0s;
  • the rail consumption in the forging stage is 2.0mm ⁇ 4.0mm
  • the forging time is 1.5s ⁇ 3.0s
  • the average speed is 0.60mm/s ⁇ 2.60mm/s.
  • compressed air with a pressure value of 50 kPa to 300 kPa is uniformly sprayed on the top, sides and lower jaw of the rail head.
  • the conveying speed of the conveying roller is set to 0.2 m/s to 2.5 m/s.
  • the main chemical composition of the hypereutectoid rail includes:
  • the mass fraction of carbon is between 0.90% and 1.20%, the mass fraction of silicon is between 0.10% and 1.00%, the mass fraction of manganese is between 0.60% and 1.50%, the mass fractions of phosphorus and sulfur do not exceed 0.020%, the mass fraction of chromium does not exceed 0.3%, and the mass fraction of vanadium does not exceed 0.01%.
  • the minimum tensile strength of the hypereutectoid rail is 1200 MPa, and the minimum hardness of the hypereutectoid rail head is 400 HB.
  • Another aspect of the present invention is to provide a device for improving the hardness of the re-austenitization zone of a hypereutectoid rail joint, the device being used for circumferential quenching treatment, and comprising:
  • each quenching unit comprises a rail head air box, a first air duct symmetrically distributed on the side of the rail head, and a second air duct symmetrically distributed on the lower jaw of the rail head.
  • the longitudinal lengths of the air box and the air duct are consistent, and the distances from the surfaces of the adjacent rails are the same.
  • a plurality of air outlets are evenly distributed on the air box and the air duct to spray compressed air to the rail joints.
  • each quenching unit includes a rail head air box, two first air ducts symmetrically distributed on the side of the rail head, and two second air ducts symmetrically distributed on the lower jaw of the rail head.
  • Each quenching unit independently adjusts the compressed air pressure value.
  • the pressure of the compressed air before entering the quenching device is 50 kPa to 300 kPa.
  • the total length of the quenching device composed of multiple quenching units is 10m to 50m
  • the width of the wind box is ⁇ 70mm
  • the length of the wind box and the air duct is ⁇ 150mm
  • the diameter of the air duct is ⁇ 25mm to ⁇ 30mm
  • the distance between the wind box and the air duct and the surface of the adjacent rail is 20mm to 40mm
  • the diameter of the air outlet is ⁇ 1mm to ⁇ 3mm
  • the spacing between the air outlets is 5mm to 15mm.
  • the method of the present invention is implemented by a mobile rail flash welding machine.
  • the welding process mainly includes five main stages: pre-flash, flash, accelerated burning, top forging and forging.
  • a special fixed online quenching device is used to perform circumferential air quenching treatment on the joint.
  • the ratio of the hardness of the high-strength hypereutectoid rail joint for heavy-duty railway welded by this method and device in the austenite zone to the hardness of the rail base material is 0.95-1.10, which ensures the smoothness of the joint and can easily meet the technical indicators specified in the standard.
  • the residual heat of the rail joint after welding is fully utilized to improve the hardness of the joint and effectively ensure the production efficiency.
  • FIG1 is a flow chart of an embodiment of a method for improving the hardness of a hypereutectoid rail joint re-austenitization zone provided by the present invention
  • FIG2 is a schematic diagram of an embodiment of a quenching unit provided by the present invention.
  • FIG3 is a schematic diagram of the re-austenitization zone of the rail joint provided by the present invention.
  • FIG1 is a flow chart of an embodiment of a method for improving the hardness of a hypereutectoid rail joint re-austenization zone provided by the present invention, the method comprising:
  • each processing step is connected by a conveying roller to form a production line, and the hypereutectoid rail joint is driven by the conveying roller to enter each processing step in turn.
  • the quenching length during the circumferential quenching treatment is 10 to 50 meters.
  • the above-mentioned high-strength hypereutectoid rail for heavy-duty railway is characterized in that the mass fraction of carbon in the main chemical composition of the rail is 0.90% to 1.20%, the mass fraction of silicon is 0.10% to 1.00%, the mass fraction of manganese is 0.60% to 1.50%, the mass fraction of phosphorus and sulfur does not exceed 0.020%, the mass fraction of chromium does not exceed 0.3%, and the mass fraction of vanadium does not exceed 0.01%.
  • the minimum tensile strength of the rail is 1200MPa, and the minimum hardness of the rail head is 400HB.
  • the front-end process and the back-end process in the method of the present invention are conventional processes for rail joint welding, and therefore, the present invention will not be further explained.
  • the flash process is mainly achieved by pre-flash, flash, and accelerated sintering, and the flash process is smooth, continuous and uninterrupted.
  • the heat input of the welding process and the cooling rate of the joint cooling process need to be strictly controlled.
  • the joint is subjected to the circumferential quenching treatment of step (3).
  • the basic function of the above-mentioned pre-flash stage is to make the section of the rail to be welded flat and clean through flash blasting, providing relatively uniform and flat favorable conditions and basic heat for the subsequent flash.
  • it is mainly necessary to control the high-voltage time and flash speed in this stage.
  • the high-voltage time in the pre-flash stage is 45s to 65s, and the flash speed is 0.1mm/s to 0.6mm/s.
  • the main function of the above-mentioned flash stage is to make the cross section of the rail to be welded flat and clean through flash blasting, providing relatively uniform and flat favorable conditions and basic heat for the subsequent flash.
  • it is mainly necessary to control the low pressure time and flash speed of this stage.
  • the low pressure time of the flash stage is 80s to 140s, and the flash speed is 0.1mm/s to 0.6mm/s.
  • the main function of the above-mentioned accelerated burning stage is to form a protective atmosphere in the entire welding area to prevent end face oxidation, and finally form a suitable temperature field distribution to provide conditions for upsetting.
  • the flash acceleration speed in the accelerated burning stage is 0.5mm/s to 2.0mm/s.
  • the main function of the above-mentioned upset forging stage is to make the steel rail to be welded in a high-temperature plastic state produce atomic bonding.
  • the charged upset forging time is 0.1s to 2.0s, and the upset forging timing is 1.0s to 3.0s.
  • the forging stage is mainly used to continuously apply load to the rail joint during the metal crystallization process of the joint after the rail top forging.
  • the rail consumption in the forging stage is 2.0 mm to 4.0 mm
  • the forging time is 1.5 s to 3.0 s
  • the average speed is 0.60 mm/s to 2.60 mm/s.
  • the above-mentioned circumferential quenching treatment is a process in which the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed, and the rail welded joint with residual heat from welding is accelerated to cool under the action of compressed air with a specific pressure.
  • the conveying speed of the conveying roller is set to 0.2m/s to 2.5m/s, and the quenching device is used to evenly spray compressed air with a pressure value of 50kPa to 300kPa to the top, side and lower jaw of the rail head.
  • the device is a fixed online quenching device, used for circumferential quenching treatment, and is tightly connected to the outlet end of the welding machine, and the device comprises:
  • each quenching unit comprises a rail head air box, a first air duct symmetrically distributed on the side of the rail head, and a second air duct symmetrically distributed on the lower jaw of the rail head.
  • the longitudinal lengths of the air box and the air duct are consistent, and the distances from the surfaces of the adjacent rails are the same.
  • a plurality of air outlets are evenly distributed on the air box and the air duct to spray compressed air to the rail joints.
  • each quenching unit includes a rail head air box, two first air ducts symmetrically distributed on the side of the rail head, and two second air ducts symmetrically distributed on the lower jaw of the rail head, and each quenching unit independently adjusts the compressed air pressure value. Further, the pressure value of the compressed air before entering the quenching device is 50kPa to 300kPa.
  • the total length of the quenching device composed of multiple quenching units is 10m to 50m
  • the width of the wind box is ⁇ 70mm
  • the length of the wind box and the air duct is ⁇ 150mm
  • the diameter of the air duct is ⁇ 25mm to ⁇ 30mm
  • the distance between the wind box and the air duct and the adjacent rail surface is 20mm to 40mm
  • the diameter of the air outlet is ⁇ 1mm to ⁇ 3mm
  • the spacing between the air outlets is 5mm to 15mm.
  • the device of the present invention is mainly used in the quenching treatment process in the above method.
  • the welded rail joint is conveyed to a fixed quenching device through a conveying roller, and is driven by the conveying roller to pass through multiple quenching units in sequence for continuous quenching treatment.
  • the cooling effect of the rail joint is better, and on the other hand, the working efficiency of the entire welding production line is higher.
  • the mass fraction of carbon in the test rail material is 0.91%
  • the mass fraction of silicon is 0.46%
  • the mass fraction of manganese is 0.81%
  • the tensile strength of the rail is 1200MPa-1300MPa
  • the rail head hardness is 405HB-415HB.
  • the high-pressure time in the pre-flash stage of continuous flash welding is 45s, and the flash speed is 0.1mm/s; the low-pressure time in the flash stage is 80s, and the flash speed is 0.1mm/s; the flash acceleration speed in the accelerated burning stage is 0.5mm/s; the charged upsetting time in the upsetting stage is 0.1s, and the upsetting timing is 1.0s; the rail consumption in the forging stage is 2.0mm, the forging time is 1.5s, and the average speed is 0.60mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a specific running speed. Under the action of compressed air with a specific pressure, the rail has a welding residual. The process of accelerated cooling of hot rail welding joints.
  • the rail running speed is 0.2m/s; the effective total quenching length of the residual heat quenching device at the rear end of the welding process is 40m; the length of the independent quenching unit wind box and the air duct is 160mm, the width of the rail top wind box is 72mm, the inner diameter of the air duct is ⁇ 30mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 20mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 3mm, and the spacing between the air outlets is 8mm; the pressure value of the compressed air before entering the quenching device is 300kPa.
  • the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this embodiment is 0.95, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements.
  • the microstructure of the standard inspection part of the joint is pearlite, without abnormal structures such as martensite or bainite. The joint and its performance meet the standard technical requirements.
  • the mass fraction of carbon in the test rail material is 1.18%
  • the mass fraction of silicon is 0.56%
  • the mass fraction of manganese is 0.78%
  • the tensile strength of the rail is 1380MPa-1480MPa
  • the rail head hardness is 425HB-450HB.
  • the high pressure time of the pre-flash stage of continuous flash welding is 65s, and the flash speed is 0.6mm/s; the low pressure time of the flash stage is 140s, and the flash speed is 0.6mm/s; the flash acceleration speed of the accelerated burning stage is 2.0mm/s; the charged upsetting time of the upsetting stage is 2.0s, and the upsetting timing is 3.0s; the rail consumption in the forging stage is 4.0mm, the forging time is 3.0s, and the average speed is 2.60mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool.
  • the running speed of the rail is 2.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 20m; the length of the independent quenching unit wind box and the air duct is 150mm, the width of the wind box on the top of the rail is 70mm, the inner diameter of the air duct is ⁇ 25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 100kPa.
  • the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this embodiment is 1.02, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements.
  • the microstructure of the standard inspection part of the joint is pearlite, without abnormal structures such as martensite or bainite. The joint and its performance meet the standard technical requirements.
  • the mass fraction of carbon in the test rail material is 1.10%
  • the mass fraction of silicon is 0.73%
  • the mass fraction of manganese is 1.10%
  • the tensile strength of the rail is 1300MPa-1420MPa
  • the rail head hardness is 415HB-440HB.
  • the high pressure time in the pre-flash stage of continuous flash welding is 50s, and the flash speed is 0.4mm/s; the low pressure time in the flash stage is 100s, and the flash speed is 0.5mm/s; the flash acceleration speed in the accelerated burning stage is 1.7mm/s; the charged upsetting time in the upsetting stage is 1.2s, and the upsetting timing is 1.1s; the rail consumption in the forging stage is 2.4mm, the forging time is 2.0s, and the average speed is 1.2mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool.
  • the running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 35m; the length of the independent quenching unit wind box and the air duct is 155mm, the width of the wind box on the top of the rail is 72mm, the inner diameter of the air duct is ⁇ 25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 200kPa.
  • the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this embodiment is 0.98, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements.
  • the microstructure of the standard inspection part of the joint is pearlite, without abnormal structures such as martensite or bainite. The joint and its performance meet the standard technical requirements.
  • the mass fraction of carbon in the test rail material is 1.10%
  • the mass fraction of silicon is 0.73%
  • the mass fraction of manganese is 1.10%
  • the tensile strength of the rail is 1300MPa ⁇ 1420MPa
  • the rail head hardness is 415HB ⁇ 440HB.
  • the high pressure time in the pre-flash stage of continuous flash welding is 50s, and the flash speed is 0.4mm/s; the low pressure time in the flash stage is 100s, and the flash speed is 0.5mm/s; the flash acceleration speed in the accelerated burning stage is 1.7mm/s; the charged upsetting time in the upsetting stage is 1.2s, and the upsetting timing is 1.1s; the rail consumption in the forging stage is 2.4mm, the forging time is 2.0s, and the average speed is 1.2mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool.
  • the rail running speed is 3.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 8m; the independent quenching unit wind box and air duct
  • the length is 150mm, the width of the wind box on the top of the rail is 70mm, the inner diameter of the air duct is ⁇ 25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 2mm, and the distance between the air outlets is 20mm; the pressure value before the compressed air enters the quenching device is 40kPa.
  • the ratio of the hardness of the re-austenitizing zone of the rail joint to the hardness of the rail base material in this comparative example is 0.75, which cannot meet the standard requirements.
  • the main difference between this comparative example and Example 3 lies in the post-weld quenching device and the quenching method. After welding is completed, the rail passes through the quenching device at a running speed exceeding the claims of this patent, and the quenching device is short in length and the compressed air pressure is low, which results in the rail joint cooling speed being too slow, and the hardness of the joint in the re-austenitizing zone cannot be improved. That is, when the rail material and welding method are the same, the method of this comparative example cannot achieve the expected effect.
  • the mass fraction of carbon in the test rail material is 1.10%
  • the mass fraction of silicon is 0.73%
  • the mass fraction of manganese is 1.10%
  • the tensile strength of the rail is 1300MPa ⁇ 1420MPa
  • the rail head hardness is 415HB ⁇ 440HB.
  • the high pressure time in the pre-flash stage of continuous flash welding is 50s, and the flash speed is 0.4mm/s; the low pressure time in the flash stage is 100s, and the flash speed is 0.5mm/s; the flash acceleration speed in the accelerated burning stage is 1.7mm/s; the charged upsetting time in the upsetting stage is 1.2s, and the upsetting timing is 1.1s; the rail consumption in the forging stage is 2.4mm, the forging time is 2.0s, and the average speed is 1.2mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with welding residual heat is accelerated to cool.
  • the running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 60m; the length of the independent quenching unit wind box and the air duct is 150mm, the width of the wind box on the top of the rail is 70mm, the internal diameter of the air duct is ⁇ 30mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 2mm, and the distance between the air outlets is 15mm; the pressure value of the compressed air before entering the quenching device is 350kPa.
  • the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this comparative example is 1.3, the local hardness of the joint is too high, the smoothness of the joint cannot be guaranteed, and the technical indicators do not meet the standard requirements. At the same time, abnormal martensitic structure was detected in the standard inspection part of the joint.
  • the main difference between this comparative example and Example 3 lies in the post-weld quenching device and the quenching method.
  • the rail passes through the quenching device at a certain speed, and the quenching device is long and the compressed air pressure is high, which leads to The cooling speed of the rail joint is too fast, so that the hardness of the joint austenitization zone increases beyond the standard requirement, and the microstructure is also abnormal. That is, under the condition of the same rail material and welding method, the comparative method cannot achieve the expected effect.
  • the mass fraction of carbon in the test rail material is 1.10%
  • the mass fraction of silicon is 0.73%
  • the mass fraction of manganese is 1.10%
  • the tensile strength of the rail is 1300MPa ⁇ 1420MPa
  • the rail head hardness is 415HB ⁇ 440HB.
  • the high pressure time in the pre-flash stage of continuous flash welding is 70s, and the flash speed is 0.1mm/s; the low pressure time in the flash stage is 160s, and the flash speed is 0.1mm/s; the flash acceleration speed in the accelerated burning stage is 0.5mm/s; the charged upsetting time in the upsetting stage is 0.1s, and the upsetting timing is 1.0s; the rail consumption in the forging stage is 1.0mm, the forging time is 1.2s, and the average speed is 0.40mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool.
  • the running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 35m; the length of the independent quenching unit wind box and the air duct is 155mm, the width of the wind box on the top of the rail is 72mm, the internal diameter of the air duct is ⁇ 25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 200kPa.
  • the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this comparative example is 1.25, the local hardness of the joint is too high, the smoothness of the joint cannot be guaranteed, and the technical indicators do not meet the standard requirements. At the same time, abnormal martensitic structure was detected in the standard inspection part of the joint.
  • the main difference between this comparative example and Example 3 lies in the welding method.
  • the comparative example adopts a higher high pressure time and a lower low pressure time than the claims of this patent, resulting in a large welding heat input; adopts a lower flash speed at each stage than the claims of this patent, resulting in a reduced rail consumption and less heat loss; adopts a lower top forging and forging rail consumption than the claims of this patent, resulting in a reduced rail consumption and less heat loss.
  • the cooling rate is too fast, and the ratio of the hardness of the joint re-austenitization zone to the hardness of the rail base material does not meet the standard technical requirements.
  • the comparative example method cannot achieve the expected effect.
  • the mass fraction of carbon in the test rail material is 1.10%
  • the mass fraction of silicon is 0.73%
  • the mass fraction of manganese is 1.10%
  • the tensile strength of the rail is 1300MPa ⁇ 1420MPa
  • the rail head hardness is 415HB ⁇ 440HB.
  • the high pressure time in the pre-flash stage of continuous flash welding is 40s, and the flash speed is 0.8mm/s; the low pressure time in the flash stage is 50s, and the flash speed is 1.0mm/s; the flash acceleration speed in the accelerated burning stage is 2.1mm/s; the charged upsetting time in the upsetting stage is 0.1s, and the upsetting timing is 1.0s; the rail consumption in the forging stage is 5.0mm, the forging time is 1.0s, and the average speed is 0.60mm/s.
  • the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool.
  • the running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 35m; the length of the independent quenching unit wind box and the air duct is 155mm, the width of the wind box on the top of the rail is 72mm, the inner diameter of the air duct is ⁇ 25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is ⁇ 2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 200kPa.
  • the ratio of the hardness of the re-austenitized zone of the rail joint in this comparative example to the hardness of the rail base material is 0.78, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements.
  • the microstructure of the standard inspection part in the joint is pearlite, without abnormal structures such as martensite or bainite.
  • the comparative example adopts a lower high pressure time and low pressure time than the patent claims, resulting in a small welding heat input; adopts a higher flash speed at each stage than the patent claims, resulting in an increased rail consumption and a large heat loss; adopts a higher top forging and forging rail consumption than the patent claims, resulting in an increased rail consumption and a large heat loss.
  • the cooling rate is too slow, and the ratio of the hardness of the joint re-austenitization zone to the hardness of the rail base material does not meet the standard technical requirements.
  • the comparative example method cannot achieve the expected effect.

Landscapes

  • Chemical & Material Sciences (AREA)
  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Materials Engineering (AREA)
  • Metallurgy (AREA)
  • Organic Chemistry (AREA)
  • Physics & Mathematics (AREA)
  • Thermal Sciences (AREA)
  • Crystallography & Structural Chemistry (AREA)
  • Heat Treatment Of Articles (AREA)

Abstract

Disclosed in the present invention are a method and a device for improving the hardness of a reaustenitizing area of a hypereutectoid steel rail joint. The method comprises: performing front-end treatment; subjecting a hypereutectoid steel rail joint to flash welding treatment, wherein welding comprises the stages of pre-flashing, flashing, accelerated burning, upsetting and forging; subjecting the welded hypereutectoid steel rail joint, which has welding waste heat, to circumferential quenching treatment, wherein the circumferential quenching treatment comprises respectively evenly spraying and blowing compressed air to a rail head top, a rail head side and a rail head lower jaw to perform accelerated cooling; and performing back-end treatment. The ratio of the hardness of a reaustenitizing area of the high-strength hypereutectoid steel rail joint, which is welded by means of the method and the device, for heavy haul railway to the hardness of a steel rail base metal is 0.95-1.10, such that the technical index requirements of standard regulations can be easily satisfied while the smoothness of the joint is guaranteed; and the waste heat of the welded steel rail joint is fully utilized after the welding is completed, such that the production efficiency is effectively guaranteed while the joint hardness is improved.

Description

一种提高过共析钢轨接头再奥氏体化区硬度的方法及装置A method and device for improving the hardness of the re-austenitization zone of a hypereutectoid rail joint 技术领域Technical Field
本发明涉及钢轨焊接技术领域，尤其涉及一种提高过共析钢轨接头再奥氏体化区硬度的方法及装置。The invention relates to the technical field of rail welding, and in particular to a method and a device for improving the hardness of a re-austenitizing zone of a hypereutectoid rail joint.
背景技术Background technique
在钢轨生产领域，通常将碳含量超过0.90％的钢轨称之为过共析钢轨，技术人员采用通过增加基体中渗碳体片厚度和渗碳体密度来提升钢轨的硬度与耐磨性，即提高碳含量以获得更高的硬度，钢轨的强度和硬度越高，钢轨的焊接性能越差，而焊接接头是铁路线路上的薄弱环节，因此重载钢轨焊接接头性能的优化也是国内外学者研究的重点。In the field of rail production, rails with a carbon content of more than 0.90% are usually called hypereutectoid rails. Technicians increase the thickness of cementite sheets and cementite density in the matrix to improve the hardness and wear resistance of the rails, that is, increase the carbon content to obtain higher hardness. The higher the strength and hardness of the rails, the worse the welding performance of the rails. The welded joints are the weak link in the railway lines. Therefore, the optimization of the performance of heavy-load rail welded joints is also a focus of research by scholars at home and abroad.
钢轨闪光焊再奥氏体化区是指钢轨接头中在焊接加热过程中发生奥氏体相变的区域。因加热和冷却过程中的相变规律与热处理正火过程相同，故该区域通常也被称为正火区。通常情况下，钢轨闪光焊接再奥氏体化区的显微组织、拉伸以及冲击性能会优于母材。但不同化学成分和供货状态的钢轨，其闪光焊接头再奥氏体化区域的硬度指标与母材相比会有不同的状态。一般而言，钢轨的硬度主要由冷却速率决定，同样起始温度的钢轨材质金属，冷却过程中的冷却速率越大，硬度越高。如果焊接后再奥氏体化区的冷却速率大于母材的冷却速率，则再奥氏体化区的硬度将高于母材；如果焊接后再奥氏体化区的冷却速率小于母材的冷却速率，则再奥氏体化区的硬度将低于母材，再奥氏体区化硬度与钢轨母材相比，过高或过低均对接头服役过程中的平顺性造成影响，且马氏体、贝氏体等异常有害组织也会对钢轨接头的性能造成影响。The re-austenitizing zone of rail flash welding refers to the area in the rail joint where austenite phase transformation occurs during the welding heating process. Because the phase transformation law during heating and cooling is the same as the heat treatment normalizing process, this area is also usually called the normalizing zone. Under normal circumstances, the microstructure, tensile and impact properties of the re-austenitizing zone of rail flash welding are better than those of the base material. However, the hardness index of the re-austenitizing zone of the flash welded joint of rails with different chemical compositions and supply conditions will be different from that of the base material. Generally speaking, the hardness of the rail is mainly determined by the cooling rate. For rail material metals with the same starting temperature, the greater the cooling rate during the cooling process, the higher the hardness. If the cooling rate of the re-austenitizing zone after welding is greater than the cooling rate of the base material, the hardness of the re-austenitizing zone will be higher than that of the base material; if the cooling rate of the re-austenitizing zone after welding is less than the cooling rate of the base material, the hardness of the re-austenitizing zone will be lower than that of the base material. Compared with the base material of the rail, the hardness of the re-austenitizing zone is too high or too low, which will affect the smoothness of the joint during service, and abnormal harmful structures such as martensite and bainite will also affect the performance of the rail joint.
因此，现有技术中存在对提高过共析钢轨接头再奥氏体化区硬度的方 法改进的需求。Therefore, there are methods in the prior art to improve the hardness of the re-austenitized zone of the hypereutectoid rail joint. The need for law improvement.
发明内容Summary of the invention
有鉴于此，本发明实施例的目的在于提出一种提高过共析钢轨接头再奥氏体化区硬度的方法及装置，通过控制焊接参数和焊后冷却处理以提高重载铁路用高强过共析钢轨接头再奥氏体区硬度，有效保障钢轨接头的平顺性。In view of this, the purpose of the embodiments of the present invention is to propose a method and device for improving the hardness of the re-austenization zone of a hypereutectoid rail joint, by controlling welding parameters and post-weld cooling treatment to improve the hardness of the re-austenization zone of a high-strength hypereutectoid rail joint for heavy-duty railways, thereby effectively ensuring the smoothness of the rail joint.
基于上述目的，本发明实施例一方面提供了一种提高过共析钢轨接头再奥氏体化区硬度的方法，所述方法包括：Based on the above purpose, an embodiment of the present invention provides a method for improving the hardness of a hypereutectoid rail joint re-austenitization zone, the method comprising:
(1)将过共析钢轨接头进行前端处理；(1) Perform front-end processing on the hypereutectoid rail joint;
(2)将过共析钢轨接头进行闪光焊接处理，焊接包括预闪光、闪光、加速烧化、顶锻以及锻造阶段；(2) flash welding the hypereutectoid rail joint, including pre-flash, flash, accelerated burning, top forging and forging stages;
(3)对焊接后具有焊接余热的过共析钢轨接头进行周向淬火处理，周向淬火处理包括分别对轨头顶部、轨头侧部以及轨头下颚均匀喷吹压缩空气进行加速冷却；(3) performing circumferential quenching treatment on the hypereutectoid rail joint with residual heat after welding, wherein the circumferential quenching treatment includes uniformly spraying compressed air on the top, side and lower jaw of the rail head to accelerate cooling;
(4)将过共析钢轨接头进行后端处理；(4) performing back-end processing on the hypereutectoid rail joint;
其中，每一个处理工序之间通过传送辊道连接以形成生产线，过共析钢轨接头通过传送辊道带动依次进入每一个处理工序中，周向淬火处理时的淬火长度为10～50m。Among them, each processing step is connected by a conveying roller to form a production line, and the hypereutectoid rail joint is driven by the conveying roller to enter each processing step in turn. The quenching length during the circumferential quenching treatment is 10 to 50 meters.
在一些实施方式中，步骤(2)的焊接处理包括：In some embodiments, the welding process of step (2) includes:
预闪光阶段的高压时间为45s～65s，闪光速度为0.1mm/s～0.6mm/s；The high-voltage time in the pre-flash stage is 45s to 65s, and the flash speed is 0.1mm/s to 0.6mm/s;
闪光阶段的低压时间为80s～140s，闪光速度为0.1mm/s～0.6mm/s；The low pressure time in the flash stage is 80s to 140s, and the flash speed is 0.1mm/s to 0.6mm/s;
加速烧化阶段的闪光加速速度为0.5mm/s～2.0mm/s；The flash acceleration speed in the accelerated burning stage is 0.5mm/s to 2.0mm/s;
顶锻阶段的带电顶锻时间为0.1s～2.0s，顶锻计时为1.0s～3.0s；The live forging time in the forging stage is 0.1s to 2.0s, and the forging timing is 1.0s to 3.0s;
锻造阶段钢轨消耗量为2.0mm～4.0mm，锻造时间为1.5s～3.0s，平均速度为0.60mm/s～2.60mm/s。 The rail consumption in the forging stage is 2.0mm~4.0mm, the forging time is 1.5s~3.0s, and the average speed is 0.60mm/s~2.60mm/s.
在一些实施方式中，对轨头顶部、轨头侧部以及轨头下颚均匀喷吹压力值为50kPa～300kPa的压缩空气。In some embodiments, compressed air with a pressure value of 50 kPa to 300 kPa is uniformly sprayed on the top, sides and lower jaw of the rail head.
在一些实施方式中，设置传送辊道的传送速度为0.2m/s～2.5m/s。In some embodiments, the conveying speed of the conveying roller is set to 0.2 m/s to 2.5 m/s.
在一些实施方式中，过共析钢轨的主要化学成分包括：In some embodiments, the main chemical composition of the hypereutectoid rail includes:
碳的质量分数处于0.90％～1.20％、硅的质量分数处于0.10％～1.00％、锰的质量分数处于0.60％～1.50％、磷和硫的质量分数均不超过0.020％，铬的质量分数不超过0.3％以及钒的质量分数不超过0.01％。The mass fraction of carbon is between 0.90% and 1.20%, the mass fraction of silicon is between 0.10% and 1.00%, the mass fraction of manganese is between 0.60% and 1.50%, the mass fractions of phosphorus and sulfur do not exceed 0.020%, the mass fraction of chromium does not exceed 0.3%, and the mass fraction of vanadium does not exceed 0.01%.
在一些实施方式中，过共析钢轨的最小抗拉强度为1200MPa，过共析钢轨轨头的最小硬度为400HB。In some embodiments, the minimum tensile strength of the hypereutectoid rail is 1200 MPa, and the minimum hardness of the hypereutectoid rail head is 400 HB.
本发明实施例另一方面还提供了一种提高过共析钢轨接头再奥氏体化区硬度的装置，装置用于周向淬火处理，该装置包括：Another aspect of the present invention is to provide a device for improving the hardness of the re-austenitization zone of a hypereutectoid rail joint, the device being used for circumferential quenching treatment, and comprising:
传送辊道；Conveyor rollers;
沿传送辊道方向依次排列的多个淬火单元，每一个淬火单元包括轨头风盒、对称分布于轨头侧面的第一风管以及对称分布于轨头下颚的第二风管，风盒与风管的纵向长度一致，并且与其相邻钢轨表面的距离相同，风盒与风管上均匀分布多个出气孔以向钢轨接头喷吹压缩空气。A plurality of quenching units are arranged in sequence along the conveying roller direction, each quenching unit comprises a rail head air box, a first air duct symmetrically distributed on the side of the rail head, and a second air duct symmetrically distributed on the lower jaw of the rail head. The longitudinal lengths of the air box and the air duct are consistent, and the distances from the surfaces of the adjacent rails are the same. A plurality of air outlets are evenly distributed on the air box and the air duct to spray compressed air to the rail joints.
在一些实施方式中，每一个淬火单元包括一个轨头风盒、对称分布于轨头侧面的两个第一风管以及对称分布于轨头下颚的两个第二风管，每一个淬火单元独立调控压缩空气压力值。In some embodiments, each quenching unit includes a rail head air box, two first air ducts symmetrically distributed on the side of the rail head, and two second air ducts symmetrically distributed on the lower jaw of the rail head. Each quenching unit independently adjusts the compressed air pressure value.
在一些实施方式中，压缩空气进入淬火装置前的压力值为50kPa～300kPa。In some embodiments, the pressure of the compressed air before entering the quenching device is 50 kPa to 300 kPa.
在一些实施方式中，多个淬火单元组成的淬火装置的总长度为10m～50m，风盒宽度≥70mm，风盒和风管的长度≥150mm，风管的直径为Φ25mm～Φ30mm，风盒和风管与其相邻钢轨表面的距离为20mm～40mm，出气孔直径为Φ1mm～Φ3mm，出气孔之间的间距为5mm～15mm。In some embodiments, the total length of the quenching device composed of multiple quenching units is 10m to 50m, the width of the wind box is ≥70mm, the length of the wind box and the air duct is ≥150mm, the diameter of the air duct is Φ25mm to Φ30mm, the distance between the wind box and the air duct and the surface of the adjacent rail is 20mm to 40mm, the diameter of the air outlet is Φ1mm to Φ3mm, and the spacing between the air outlets is 5mm to 15mm.
本发明至少具有以下有益技术效果： The present invention has at least the following beneficial technical effects:
本发明的方法采用钢轨移动式闪光焊机实现，焊接过程主要包括预闪光、闪光、加速烧化、顶锻及锻造等5个主要阶段，闪光焊接过程结束后，采用特殊的固定式在线淬火装置，对接头进行周向空气淬火处理。采用该方法及装置焊接的重载铁路用高强过共析钢轨接头再奥氏体区硬度与钢轨母材硬度的比值为0.95～1.10，保障接头平顺性的同时，能够容易的满足标准规定的技术指标要求，焊接完成后充分利用焊接后钢轨接头余热，提升接头硬度的同时有效保障了生产效率。The method of the present invention is implemented by a mobile rail flash welding machine. The welding process mainly includes five main stages: pre-flash, flash, accelerated burning, top forging and forging. After the flash welding process is completed, a special fixed online quenching device is used to perform circumferential air quenching treatment on the joint. The ratio of the hardness of the high-strength hypereutectoid rail joint for heavy-duty railway welded by this method and device in the austenite zone to the hardness of the rail base material is 0.95-1.10, which ensures the smoothness of the joint and can easily meet the technical indicators specified in the standard. After the welding is completed, the residual heat of the rail joint after welding is fully utilized to improve the hardness of the joint and effectively ensure the production efficiency.
附图说明BRIEF DESCRIPTION OF THE DRAWINGS
为了更清楚地说明本发明实施例或现有技术中的技术方案，下面将对实施例或现有技术描述中所需要使用的附图作简单地介绍，显而易见地，下面描述中的附图仅仅是本发明的一些实施例，对于本领域普通技术人员来讲，在不付出创造性劳动的前提下，还可以根据这些附图获得其他的实施例。In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments or the description of the prior art will be briefly introduced below. Obviously, the drawings in the following description are only some embodiments of the present invention. For ordinary technicians in this field, other embodiments can be obtained based on these drawings without paying creative work.
图1为本发明提供的提高过共析钢轨接头再奥氏体化区硬度的方法实施例的流程图；FIG1 is a flow chart of an embodiment of a method for improving the hardness of a hypereutectoid rail joint re-austenitization zone provided by the present invention;
图2为本发明提供的淬火单元的实施例的示意图；FIG2 is a schematic diagram of an embodiment of a quenching unit provided by the present invention;
图3为本发明提供的钢轨接头再奥氏体化区的示意图。FIG3 is a schematic diagram of the re-austenitization zone of the rail joint provided by the present invention.
具体实施方式Detailed ways
为使本发明的目的、技术方案和优点更加清楚明白，以下结合具体实施例，并参照附图，对本发明实施例进一步详细说明。In order to make the objectives, technical solutions and advantages of the present invention more clearly understood, the embodiments of the present invention are further described in detail below in combination with specific embodiments and with reference to the accompanying drawings.
本发明的说明书和权利要求书及上述附图说明中的术语“包括”和“具有”以及它们的任何变形，意图在于覆盖不排他的包含；本发明的说明书和权利要求书或上述附图中的术语“第一”、“第二”等是用于区别不同对象，而不是用于描述特定顺序。“多个”的含义是两个或两个以上，除非另有明确具体的限定。The terms "including" and "having" and any variations thereof in the specification and claims of the present invention and the above-mentioned drawings are intended to cover non-exclusive inclusions; the terms "first", "second", etc. in the specification and claims of the present invention or the above-mentioned drawings are used to distinguish different objects rather than to describe a specific order. "Multiple" means two or more, unless otherwise clearly and specifically defined.
此外，在本文中提及“实施例”意味着，结合实施例描述的特定特征、 结构或特性可以包含在本发明的至少一个实施例中。在说明书中的各个位置出现该短语并不一定均是指相同的实施例，也不是与其它实施例互斥的独立的或备选的实施例。本领域技术人员显式地和隐式地理解的是，本文所描述的实施例可以与其它实施例相结合。In addition, reference to an "embodiment" in this document means that the specific features, The structure or characteristic may be included in at least one embodiment of the present invention. The appearance of the phrase in various places in the specification does not necessarily refer to the same embodiment, nor is it an independent or alternative embodiment that is mutually exclusive with other embodiments. It is explicitly and implicitly understood by those skilled in the art that the embodiments described herein can be combined with other embodiments.
如图1所示为本发明提供的提高过共析钢轨接头再奥氏体化区硬度的方法实施例的流程图，该方法包括：FIG1 is a flow chart of an embodiment of a method for improving the hardness of a hypereutectoid rail joint re-austenization zone provided by the present invention, the method comprising:
(1)将过共析钢轨接头进行前端处理；(1) Perform front-end processing on the hypereutectoid rail joint;
(2)将过共析钢轨接头进行闪光焊接处理，焊接包括预闪光、闪光、加速烧化、顶锻以及锻造阶段；(2) flash welding the hypereutectoid rail joint, including pre-flash, flash, accelerated burning, top forging and forging stages;
(3)对焊接后具有焊接余热的过共析钢轨接头进行周向淬火处理，周向淬火处理包括分别对轨头顶部、轨头侧部以及轨头下颚均匀喷吹压缩空气进行加速冷却；(3) performing circumferential quenching treatment on the hypereutectoid rail joint with residual heat after welding, wherein the circumferential quenching treatment includes uniformly spraying compressed air on the top, side and lower jaw of the rail head to accelerate cooling;
(4)将过共析钢轨接头进行后端处理；(4) performing back-end processing on the hypereutectoid rail joint;
其中，每一个处理工序之间通过传送辊道连接以形成生产线，过共析钢轨接头通过传送辊道带动依次进入每一个处理工序中，周向淬火处理时的淬火长度为10～50m。Among them, each processing step is connected by a conveying roller to form a production line, and the hypereutectoid rail joint is driven by the conveying roller to enter each processing step in turn. The quenching length during the circumferential quenching treatment is 10 to 50 meters.
进一步地，上述的重载铁路用高强过共析钢轨，其特征在于钢轨的主要化学成分中碳的质量分数处于0.90％～1.20％、硅的质量分数处于0.10％～1.00％、锰的质量分数处于0.60％～1.50％、磷和硫的质量分数均不超过0.020％，铬的质量分数不超过0.3％以及钒的质量分数不超过0.01％。钢轨的最小抗拉强度为1200MPa，轨头最小硬度为400HB。Furthermore, the above-mentioned high-strength hypereutectoid rail for heavy-duty railway is characterized in that the mass fraction of carbon in the main chemical composition of the rail is 0.90% to 1.20%, the mass fraction of silicon is 0.10% to 1.00%, the mass fraction of manganese is 0.60% to 1.50%, the mass fraction of phosphorus and sulfur does not exceed 0.020%, the mass fraction of chromium does not exceed 0.3%, and the mass fraction of vanadium does not exceed 0.01%. The minimum tensile strength of the rail is 1200MPa, and the minimum hardness of the rail head is 400HB.
进一步地，本发明的方法中的前端工序和后端工序为钢轨接头焊接时的常规工序，因此，本发明不再作进一步解释。对于步骤(2)中的连续闪光焊接，闪光过程主要通过预闪光、闪光、加速烧化实现，闪光过程平稳连续无中断。为达到提高过共析钢轨接头再奥氏体区硬度的目的，需严格控制焊接过程的热量输入以及接头冷却过程的冷却速率。并且在焊接完成后对接头进行步骤(3)的周向淬火处理。 Furthermore, the front-end process and the back-end process in the method of the present invention are conventional processes for rail joint welding, and therefore, the present invention will not be further explained. For the continuous flash welding in step (2), the flash process is mainly achieved by pre-flash, flash, and accelerated sintering, and the flash process is smooth, continuous and uninterrupted. In order to achieve the purpose of improving the hardness of the hypereutectoid rail joint in the austenite zone, the heat input of the welding process and the cooling rate of the joint cooling process need to be strictly controlled. And after the welding is completed, the joint is subjected to the circumferential quenching treatment of step (3).
进一步地，上述的预闪光阶段的基础作用是通过闪光爆破使得钢轨待焊截面平整清洁，为后续的闪光提供相对均匀平整的有利条件和基础热量。为达到控制热量输入的目的，主要需要控制该阶段高压时间和闪光速度。预闪光阶段的高压时间为45s～65s，闪光速度为0.1mm/s～0.6mm/s。Furthermore, the basic function of the above-mentioned pre-flash stage is to make the section of the rail to be welded flat and clean through flash blasting, providing relatively uniform and flat favorable conditions and basic heat for the subsequent flash. In order to achieve the purpose of controlling heat input, it is mainly necessary to control the high-voltage time and flash speed in this stage. The high-voltage time in the pre-flash stage is 45s to 65s, and the flash speed is 0.1mm/s to 0.6mm/s.
进一步地，上述的闪光阶段主要作用是通过闪光爆破使得钢轨待焊截面平整清洁，为后续的闪光提供相对均匀平整的有利条件和基础热量。为达到控制热量输入的目的，主要需要控制该阶段低压时间和闪光速度。闪光阶段的低压时间为80s～140s，闪光速度为0.1mm/s～0.6mm/s。Furthermore, the main function of the above-mentioned flash stage is to make the cross section of the rail to be welded flat and clean through flash blasting, providing relatively uniform and flat favorable conditions and basic heat for the subsequent flash. In order to achieve the purpose of controlling heat input, it is mainly necessary to control the low pressure time and flash speed of this stage. The low pressure time of the flash stage is 80s to 140s, and the flash speed is 0.1mm/s to 0.6mm/s.
进一步地，上述的加速烧化阶段主要作用是在整个焊接区域形成防止端面氧化的保护气氛，最终形成合适的温度场分布，为顶锻提供条件。为达到控制热量输入的目的，主要需要控制该阶段闪光加速速度。加速烧化阶段的闪光加速速度为0.5mm/s～2.0mm/s。Furthermore, the main function of the above-mentioned accelerated burning stage is to form a protective atmosphere in the entire welding area to prevent end face oxidation, and finally form a suitable temperature field distribution to provide conditions for upsetting. In order to achieve the purpose of controlling heat input, it is mainly necessary to control the flash acceleration speed in this stage. The flash acceleration speed in the accelerated burning stage is 0.5mm/s to 2.0mm/s.
进一步地，上述的顶锻阶段主要作用是使得处于高温塑性状态的待焊钢轨产生原子间结合。为达到控制热量输入的目的，主要需要控制该阶段带电顶锻时间和顶锻计时。带电顶锻时间为0.1s～2.0s，顶锻计时为1.0s～3.0s。Furthermore, the main function of the above-mentioned upset forging stage is to make the steel rail to be welded in a high-temperature plastic state produce atomic bonding. In order to achieve the purpose of controlling heat input, it is mainly necessary to control the charged upset forging time and upset forging timing in this stage. The charged upset forging time is 0.1s to 2.0s, and the upset forging timing is 1.0s to 3.0s.
进一步地，上述的锻造阶段主要作用是在钢轨顶锻后的接头金属结晶过程中对钢轨接头持续施加载荷。锻造阶段钢轨消耗量为2.0mm～4.0mm，锻造时间为1.5s～3.0s，平均速度为0.60mm/s～2.60mm/s。Furthermore, the forging stage is mainly used to continuously apply load to the rail joint during the metal crystallization process of the joint after the rail top forging. The rail consumption in the forging stage is 2.0 mm to 4.0 mm, the forging time is 1.5 s to 3.0 s, and the average speed is 0.60 mm/s to 2.60 mm/s.
进一步地，上述的周向淬火处理是钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。具体地，设置传送辊道的传送速度为0.2m/s～2.5m/s，通过该淬火装置对轨头顶部、轨头侧部以及轨头下颚均匀喷吹压力值为50kPa～300kPa的压缩空气。Furthermore, the above-mentioned circumferential quenching treatment is a process in which the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed, and the rail welded joint with residual heat from welding is accelerated to cool under the action of compressed air with a specific pressure. Specifically, the conveying speed of the conveying roller is set to 0.2m/s to 2.5m/s, and the quenching device is used to evenly spray compressed air with a pressure value of 50kPa to 300kPa to the top, side and lower jaw of the rail head.
本发明另一方面还提供了一种上述方法中使用的提高过共析钢轨接头再奥氏体化区硬度的装置，该装置为固定式在线淬火装置，用于周向淬火处理，与焊机出口端紧密连接，该装置包括： Another aspect of the present invention provides a device for improving the hardness of the re-austenitization zone of the hypereutectoid rail joint used in the above method, the device is a fixed online quenching device, used for circumferential quenching treatment, and is tightly connected to the outlet end of the welding machine, and the device comprises:
传送辊道；Conveyor rollers;
沿传送辊道方向依次排列的多个淬火单元，每一个淬火单元包括轨头风盒、对称分布于轨头侧面的第一风管以及对称分布于轨头下颚的第二风管，风盒与风管的纵向长度一致，并且与其相邻钢轨表面的距离相同，风盒与风管上均匀分布多个出气孔以向钢轨接头喷吹压缩空气。A plurality of quenching units are arranged in sequence along the conveying roller direction, each quenching unit comprises a rail head air box, a first air duct symmetrically distributed on the side of the rail head, and a second air duct symmetrically distributed on the lower jaw of the rail head. The longitudinal lengths of the air box and the air duct are consistent, and the distances from the surfaces of the adjacent rails are the same. A plurality of air outlets are evenly distributed on the air box and the air duct to spray compressed air to the rail joints.
在一些实施例中，每一个淬火单元包括一个轨头风盒、对称分布于轨头侧面的两个第一风管以及对称分布于轨头下颚的两个第二风管，每一个淬火单元独立调控压缩空气压力值。进一步地，压缩空气进入淬火装置前的压力值为50kPa～300kPa。In some embodiments, each quenching unit includes a rail head air box, two first air ducts symmetrically distributed on the side of the rail head, and two second air ducts symmetrically distributed on the lower jaw of the rail head, and each quenching unit independently adjusts the compressed air pressure value. Further, the pressure value of the compressed air before entering the quenching device is 50kPa to 300kPa.
在一些实施例中，多个淬火单元组成的淬火装置的总长度为10m～50m，风盒宽度≥70mm，风盒和风管的长度≥150mm，风管的直径为Φ25mm～Φ30mm，风盒和风管与其相邻钢轨表面的距离为20mm～40mm，出气孔直径为Φ1mm～Φ3mm，出气孔之间的间距为5mm～15mm。In some embodiments, the total length of the quenching device composed of multiple quenching units is 10m to 50m, the width of the wind box is ≥70mm, the length of the wind box and the air duct is ≥150mm, the diameter of the air duct is Φ25mm to Φ30mm, the distance between the wind box and the air duct and the adjacent rail surface is 20mm to 40mm, the diameter of the air outlet is Φ1mm to Φ3mm, and the spacing between the air outlets is 5mm to 15mm.
本发明的装置主要应用于上述方法中的淬火处理工序，焊接后的钢轨接头通过传送辊道传送至固定式淬火装置中，通过传送辊道带动依次通过多个淬火单元，连续进行淬火处理，一方面使得钢轨接头的冷却效果更好，另一方面使得整个焊接生产线的工作效率更高。The device of the present invention is mainly used in the quenching treatment process in the above method. The welded rail joint is conveyed to a fixed quenching device through a conveying roller, and is driven by the conveying roller to pass through multiple quenching units in sequence for continuous quenching treatment. On the one hand, the cooling effect of the rail joint is better, and on the other hand, the working efficiency of the entire welding production line is higher.
下面根据具体实施例进一步阐述本发明的具体实施方式。The specific implementation of the present invention is further described below based on specific examples.
实施例1Example 1
本实施例中试验用钢轨材料中碳的质量分数为0.91％、硅的质量分数为于0.46％、锰的质量分数为0.81％、钢轨的抗拉强度为1200MPa～1300MPa，轨头硬度为405HB～415HB。连续闪光焊接的预闪光阶段的高压时间为45s，闪光速度为0.1mm/s；闪光阶段的低压时间为80s，闪光速度为0.1mm/s；加速烧化阶段的闪光加速速度为0.5mm/s；顶锻阶段的带电顶锻时间为0.1s，顶锻计时为1.0s；锻造阶段钢轨消耗量为2.0mm，锻造时间为1.5s，平均速度为0.60mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余 热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为0.2m/s；焊接工序后端的余热淬火装置的有效淬火总长度为40m；独立淬火单元风盒及风管的长度为160mm、轨顶面风盒的宽度为72mm、风管内部直径为Φ30mm，风盒和风管与钢轨表面相邻的一侧的距离为20mm，且均匀分布若干出气孔，出气孔直径为Φ3mm，出气孔间距为8mm；压缩空气进入淬火装置前的压力值为300kPa。经检验，本实施例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为0.95，有效保障了接头平顺性，技术指标满足标准规定。同时接头中标准检验部位的显微组织为珠光体，无马氏体或贝氏体等异常组织。接头其与性能均满足标准技术要求。In the present embodiment, the mass fraction of carbon in the test rail material is 0.91%, the mass fraction of silicon is 0.46%, the mass fraction of manganese is 0.81%, the tensile strength of the rail is 1200MPa-1300MPa, and the rail head hardness is 405HB-415HB. The high-pressure time in the pre-flash stage of continuous flash welding is 45s, and the flash speed is 0.1mm/s; the low-pressure time in the flash stage is 80s, and the flash speed is 0.1mm/s; the flash acceleration speed in the accelerated burning stage is 0.5mm/s; the charged upsetting time in the upsetting stage is 0.1s, and the upsetting timing is 1.0s; the rail consumption in the forging stage is 2.0mm, the forging time is 1.5s, and the average speed is 0.60mm/s. After the welding is completed, the rail passes through a special quenching device along the longitudinal direction of the rail at a specific running speed. Under the action of compressed air with a specific pressure, the rail has a welding residual. The process of accelerated cooling of hot rail welding joints. The rail running speed is 0.2m/s; the effective total quenching length of the residual heat quenching device at the rear end of the welding process is 40m; the length of the independent quenching unit wind box and the air duct is 160mm, the width of the rail top wind box is 72mm, the inner diameter of the air duct is Φ30mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 20mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ3mm, and the spacing between the air outlets is 8mm; the pressure value of the compressed air before entering the quenching device is 300kPa. After inspection, the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this embodiment is 0.95, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements. At the same time, the microstructure of the standard inspection part of the joint is pearlite, without abnormal structures such as martensite or bainite. The joint and its performance meet the standard technical requirements.
实施例2Example 2
本实施例中试验用钢轨材料中碳的质量分数为1.18％、硅的质量分数为于0.56％、锰的质量分数为0.78％、钢轨的抗拉强度为1380MPa～1480MPa，轨头硬度为425HB～450HB。连续闪光焊接的预闪光阶段的高压时间为65s，闪光速度为0.6mm/s；闪光阶段的低压时间为140s，闪光速度为0.6mm/s；加速烧化阶段的闪光加速速度为2.0mm/s；顶锻阶段的带电顶锻时间为2.0s，顶锻计时为3.0s；锻造阶段钢轨消耗量为4.0mm，锻造时间为3.0s，平均速度为2.60mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为2.0m/s；焊接工序后端的余热淬火装置的有效淬火总长度为20m；独立淬火单元风盒及风管的长度为150mm、轨顶面风盒的宽度为70mm、风管内部直径为Φ25mm，风盒和风管与钢轨表面相邻的一侧的距离为30mm，且均匀分布若干出气孔，出气孔直径为Φ2mm，出气孔间距为10mm；压缩空气进入淬火装置前的压力值为100kPa。经检验，本实施例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为1.02，有效保障了接头平顺性，技术指标满足标准规定。同时接头中标准检验部位的显微组织为珠光体，无马氏体或贝氏体等异常组织。接头其与性能均满足标准技术要求。In this embodiment, the mass fraction of carbon in the test rail material is 1.18%, the mass fraction of silicon is 0.56%, the mass fraction of manganese is 0.78%, the tensile strength of the rail is 1380MPa-1480MPa, and the rail head hardness is 425HB-450HB. The high pressure time of the pre-flash stage of continuous flash welding is 65s, and the flash speed is 0.6mm/s; the low pressure time of the flash stage is 140s, and the flash speed is 0.6mm/s; the flash acceleration speed of the accelerated burning stage is 2.0mm/s; the charged upsetting time of the upsetting stage is 2.0s, and the upsetting timing is 3.0s; the rail consumption in the forging stage is 4.0mm, the forging time is 3.0s, and the average speed is 2.60mm/s. After welding, the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool. The running speed of the rail is 2.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 20m; the length of the independent quenching unit wind box and the air duct is 150mm, the width of the wind box on the top of the rail is 70mm, the inner diameter of the air duct is Φ25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 100kPa. After inspection, the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this embodiment is 1.02, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements. At the same time, the microstructure of the standard inspection part of the joint is pearlite, without abnormal structures such as martensite or bainite. The joint and its performance meet the standard technical requirements.
实施例3 Example 3
本实施例中试验用钢轨材料中碳的质量分数为1.10％、硅的质量分数为于0.73％、锰的质量分数为1.10％、钢轨的抗拉强度为1300MPa～1420MPa，轨头硬度为415HB～440HB。连续闪光焊接的预闪光阶段的高压时间为50s，闪光速度为0.4mm/s；闪光阶段的低压时间为100s，闪光速度为0.5mm/s；加速烧化阶段的闪光加速速度为1.7mm/s；顶锻阶段的带电顶锻时间为1.2s，顶锻计时为1.1s；锻造阶段钢轨消耗量为2.4mm，锻造时间为2.0s，平均速度为1.2mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为1.0m/s；焊接工序后端的余热淬火装置的有效淬火总长度为35m；独立淬火单元风盒及风管的长度为155mm、轨顶面风盒的宽度为72mm、风管内部直径为Φ25mm，风盒和风管与钢轨表面相邻的一侧的距离为30mm，且均匀分布若干出气孔，出气孔直径为Φ2mm，出气孔间距为10mm；压缩空气进入淬火装置前的压力值为200kPa。经检验，本实施例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为0.98，有效保障了接头平顺性，技术指标满足标准规定。同时接头中标准检验部位的显微组织为珠光体，无马氏体或贝氏体等异常组织。接头其与性能均满足标准技术要求。In this embodiment, the mass fraction of carbon in the test rail material is 1.10%, the mass fraction of silicon is 0.73%, the mass fraction of manganese is 1.10%, the tensile strength of the rail is 1300MPa-1420MPa, and the rail head hardness is 415HB-440HB. The high pressure time in the pre-flash stage of continuous flash welding is 50s, and the flash speed is 0.4mm/s; the low pressure time in the flash stage is 100s, and the flash speed is 0.5mm/s; the flash acceleration speed in the accelerated burning stage is 1.7mm/s; the charged upsetting time in the upsetting stage is 1.2s, and the upsetting timing is 1.1s; the rail consumption in the forging stage is 2.4mm, the forging time is 2.0s, and the average speed is 1.2mm/s. After welding, the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool. The running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 35m; the length of the independent quenching unit wind box and the air duct is 155mm, the width of the wind box on the top of the rail is 72mm, the inner diameter of the air duct is Φ25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 200kPa. After inspection, the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this embodiment is 0.98, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements. At the same time, the microstructure of the standard inspection part of the joint is pearlite, without abnormal structures such as martensite or bainite. The joint and its performance meet the standard technical requirements.
对比例1Comparative Example 1
本对比例中试验用钢轨材料中碳的质量分数为1.10％、硅的质量分数为于0.73％、锰的质量分数为1.10％、钢轨的抗拉强度为1300MPa～1420MPa，轨头硬度为415HB～440HB。连续闪光焊接的预闪光阶段的高压时间为50s，闪光速度为0.4mm/s；闪光阶段的低压时间为100s，闪光速度为0.5mm/s；加速烧化阶段的闪光加速速度为1.7mm/s；顶锻阶段的带电顶锻时间为1.2s，顶锻计时为1.1s；锻造阶段钢轨消耗量为2.4mm，锻造时间为2.0s，平均速度为1.2mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为3.0m/s；焊接工序后端的余热淬火装置的有效淬火总长度为8m；独立淬火单元风盒及风管 的长度为150mm、轨顶面风盒的宽度为70mm、风管内部直径为Φ25mm，风盒和风管与钢轨表面相邻的一侧的距离为30mm，且均匀分布若干出气孔，出气孔直径为Φ2mm，出气孔间距为20mm；压缩空气进入淬火装置前的压力值为40kPa。经检验，本对比例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为0.75，无法满足标准要求。本对比例中与实施例3的主要区别在于焊后淬火装置和淬火方法上。焊接完成后，钢轨以超过本专利权利要求的运行速度通过淬火装置，且淬火装置长度短、压缩空气压力小，导致钢轨接头冷却速度过慢，无法使得接头再奥氏体化区硬度提升。即，在钢轨材质和焊接方法相同的情况下，采用本对比例方法无法达到预期效果。In this comparative example, the mass fraction of carbon in the test rail material is 1.10%, the mass fraction of silicon is 0.73%, the mass fraction of manganese is 1.10%, the tensile strength of the rail is 1300MPa~1420MPa, and the rail head hardness is 415HB~440HB. The high pressure time in the pre-flash stage of continuous flash welding is 50s, and the flash speed is 0.4mm/s; the low pressure time in the flash stage is 100s, and the flash speed is 0.5mm/s; the flash acceleration speed in the accelerated burning stage is 1.7mm/s; the charged upsetting time in the upsetting stage is 1.2s, and the upsetting timing is 1.1s; the rail consumption in the forging stage is 2.4mm, the forging time is 2.0s, and the average speed is 1.2mm/s. After welding, the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool. The rail running speed is 3.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 8m; the independent quenching unit wind box and air duct The length is 150mm, the width of the wind box on the top of the rail is 70mm, the inner diameter of the air duct is Φ25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ2mm, and the distance between the air outlets is 20mm; the pressure value before the compressed air enters the quenching device is 40kPa. After inspection, the ratio of the hardness of the re-austenitizing zone of the rail joint to the hardness of the rail base material in this comparative example is 0.75, which cannot meet the standard requirements. The main difference between this comparative example and Example 3 lies in the post-weld quenching device and the quenching method. After welding is completed, the rail passes through the quenching device at a running speed exceeding the claims of this patent, and the quenching device is short in length and the compressed air pressure is low, which results in the rail joint cooling speed being too slow, and the hardness of the joint in the re-austenitizing zone cannot be improved. That is, when the rail material and welding method are the same, the method of this comparative example cannot achieve the expected effect.
对比例2Comparative Example 2
本对比例中试验用钢轨材料中碳的质量分数为1.10％、硅的质量分数为于0.73％、锰的质量分数为1.10％、钢轨的抗拉强度为1300MPa～1420MPa，轨头硬度为415HB～440HB。连续闪光焊接的预闪光阶段的高压时间为50s，闪光速度为0.4mm/s；闪光阶段的低压时间为100s，闪光速度为0.5mm/s；加速烧化阶段的闪光加速速度为1.7mm/s；顶锻阶段的带电顶锻时间为1.2s，顶锻计时为1.1s；锻造阶段钢轨消耗量为2.4mm，锻造时间为2.0s，平均速度为1.2mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为1.0m/s；焊接工序后端的余热淬火装置的有效淬火总长度为60m；独立淬火单元风盒及风管的长度为150mm、轨顶面风盒的宽度为70mm、风管内部直径为Φ30mm，风盒和风管与钢轨表面相邻的一侧的距离为30mm，且均匀分布若干出气孔，出气孔直径为Φ2mm，出气孔间距为15mm；压缩空气进入淬火装置前的压力值为350kPa。经检验，本对比例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为1.3，接头局部硬度过高，无法保障接头平顺性，技术指标不满足标准规定。同时接头中标准检验部位检验到马氏体异常组织。本对比例中与实施例3的主要区别在于焊后淬火装置和淬火方法上。焊接完成后，钢轨以一定速度通过淬火装置，且淬火装置长、压缩空气压力大，导 致钢轨接头冷却速度过快，使得接头再奥氏体化区硬度提升超过标准要求范围，同时显微组织也出现异常。即，在钢轨材质和焊接方法相同的情况下，采用本对比例方法无法达到预期效果。In this comparative example, the mass fraction of carbon in the test rail material is 1.10%, the mass fraction of silicon is 0.73%, the mass fraction of manganese is 1.10%, the tensile strength of the rail is 1300MPa~1420MPa, and the rail head hardness is 415HB~440HB. The high pressure time in the pre-flash stage of continuous flash welding is 50s, and the flash speed is 0.4mm/s; the low pressure time in the flash stage is 100s, and the flash speed is 0.5mm/s; the flash acceleration speed in the accelerated burning stage is 1.7mm/s; the charged upsetting time in the upsetting stage is 1.2s, and the upsetting timing is 1.1s; the rail consumption in the forging stage is 2.4mm, the forging time is 2.0s, and the average speed is 1.2mm/s. After welding, the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with welding residual heat is accelerated to cool. The running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 60m; the length of the independent quenching unit wind box and the air duct is 150mm, the width of the wind box on the top of the rail is 70mm, the internal diameter of the air duct is Φ30mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ2mm, and the distance between the air outlets is 15mm; the pressure value of the compressed air before entering the quenching device is 350kPa. After inspection, the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this comparative example is 1.3, the local hardness of the joint is too high, the smoothness of the joint cannot be guaranteed, and the technical indicators do not meet the standard requirements. At the same time, abnormal martensitic structure was detected in the standard inspection part of the joint. The main difference between this comparative example and Example 3 lies in the post-weld quenching device and the quenching method. After welding is completed, the rail passes through the quenching device at a certain speed, and the quenching device is long and the compressed air pressure is high, which leads to The cooling speed of the rail joint is too fast, so that the hardness of the joint austenitization zone increases beyond the standard requirement, and the microstructure is also abnormal. That is, under the condition of the same rail material and welding method, the comparative method cannot achieve the expected effect.
对比例3Comparative Example 3
本对比例中试验用钢轨材料中碳的质量分数为1.10％、硅的质量分数为于0.73％、锰的质量分数为1.10％、钢轨的抗拉强度为1300MPa～1420MPa，轨头硬度为415HB～440HB。连续闪光焊接的预闪光阶段的高压时间为70s，闪光速度为0.1mm/s；闪光阶段的低压时间为160s，闪光速度为0.1mm/s；加速烧化阶段的闪光加速速度为0.5mm/s；顶锻阶段的带电顶锻时间为0.1s，顶锻计时为1.0s；锻造阶段钢轨消耗量为1.0mm，锻造时间为1.2s，平均速度为0.40mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为1.0m/s；焊接工序后端的余热淬火装置的有效淬火总长度为35m；独立淬火单元风盒及风管的长度为155mm、轨顶面风盒的宽度为72mm、风管内部直径为Φ25mm，风盒和风管与钢轨表面相邻的一侧的距离为30mm，且均匀分布若干出气孔，出气孔直径为Φ2mm，出气孔间距为10mm；压缩空气进入淬火装置前的压力值为200kPa。经检验，本对比例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为1.25，接头局部硬度过高，无法保障接头平顺性，技术指标不满足标准规定。同时接头中标准检验部位检验到马氏体异常组织。本对比例中与实施例3的主要区别在于焊接方法上。对比例采用的高于本专利权利要求的高压时间、低压时间，焊接热输入量大；采用低于本专利权利要求的各阶段闪光速度，钢轨消耗量减小，热量损失少；采用低于本专利权利要求的顶锻和锻造钢轨消耗量，钢轨消耗量减小，热量损失少，在后续的空气淬火过程中，冷却速率过快，接头再奥氏体化区硬度与钢轨母材硬度的比值不满足标准技术要求。在钢轨材质相同的情况下，采用本对比例方法无法达到预期效果。In this comparative example, the mass fraction of carbon in the test rail material is 1.10%, the mass fraction of silicon is 0.73%, the mass fraction of manganese is 1.10%, the tensile strength of the rail is 1300MPa~1420MPa, and the rail head hardness is 415HB~440HB. The high pressure time in the pre-flash stage of continuous flash welding is 70s, and the flash speed is 0.1mm/s; the low pressure time in the flash stage is 160s, and the flash speed is 0.1mm/s; the flash acceleration speed in the accelerated burning stage is 0.5mm/s; the charged upsetting time in the upsetting stage is 0.1s, and the upsetting timing is 1.0s; the rail consumption in the forging stage is 1.0mm, the forging time is 1.2s, and the average speed is 0.40mm/s. After welding, the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool. The running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 35m; the length of the independent quenching unit wind box and the air duct is 155mm, the width of the wind box on the top of the rail is 72mm, the internal diameter of the air duct is Φ25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 200kPa. After inspection, the ratio of the hardness of the austenitized zone of the rail joint to the hardness of the rail base material in this comparative example is 1.25, the local hardness of the joint is too high, the smoothness of the joint cannot be guaranteed, and the technical indicators do not meet the standard requirements. At the same time, abnormal martensitic structure was detected in the standard inspection part of the joint. The main difference between this comparative example and Example 3 lies in the welding method. The comparative example adopts a higher high pressure time and a lower low pressure time than the claims of this patent, resulting in a large welding heat input; adopts a lower flash speed at each stage than the claims of this patent, resulting in a reduced rail consumption and less heat loss; adopts a lower top forging and forging rail consumption than the claims of this patent, resulting in a reduced rail consumption and less heat loss. In the subsequent air quenching process, the cooling rate is too fast, and the ratio of the hardness of the joint re-austenitization zone to the hardness of the rail base material does not meet the standard technical requirements. In the case of the same rail material, the comparative example method cannot achieve the expected effect.
对比例4 Comparative Example 4
本对比例中试验用钢轨材料中碳的质量分数为1.10％、硅的质量分数为于0.73％、锰的质量分数为1.10％、钢轨的抗拉强度为1300MPa～1420MPa，轨头硬度为415HB～440HB。连续闪光焊接的预闪光阶段的高压时间为40s，闪光速度为0.8mm/s；闪光阶段的低压时间为50s，闪光速度为1.0mm/s；加速烧化阶段的闪光加速速度为2.1mm/s；顶锻阶段的带电顶锻时间为0.1s，顶锻计时为1.0s；锻造阶段钢轨消耗量为5.0mm，锻造时间为1.0s，平均速度为0.60mm/s。焊接结束后，钢轨以某一特定的运行速度，沿钢轨纵向方向通过特殊淬火装置，在具有特定压力的压缩空气的作用下，具有焊接余热的钢轨焊接接头被加速冷却的过程。其中钢轨运行速度为1.0m/s；焊接工序后端的余热淬火装置的有效淬火总长度为35m；独立淬火单元风盒及风管的长度为155mm、轨顶面风盒的宽度为72mm、风管内部直径为Φ25mm，风盒和风管与钢轨表面相邻的一侧的距离为30mm，且均匀分布若干出气孔，出气孔直径为Φ2mm，出气孔间距为10mm；压缩空气进入淬火装置前的压力值为200kPa。经检验，本对比例中钢轨接头再奥氏体化区硬度与钢轨母材硬度的比值为0.78，有效保障了接头平顺性，技术指标满足标准规定。同时接头中标准检验部位的显微组织为珠光体，无马氏体或贝氏体等异常组织。对比例采用的低于本专利权利要求的高压时间、低压时间，焊接热输入量小；采用高于本专利权利要求的各阶段闪光速度，钢轨消耗量增加，热量损失多；采用高于本专利权利要求的顶锻和锻造钢轨消耗量，钢轨消耗量增加，热量损失多，在后续的空气淬火过程中，冷却速率过慢，接头再奥氏体化区硬度与钢轨母材硬度的比值不满足标准技术要求。在钢轨材质相同的情况下，采用本对比例方法无法达到预期效果。In this comparative example, the mass fraction of carbon in the test rail material is 1.10%, the mass fraction of silicon is 0.73%, the mass fraction of manganese is 1.10%, the tensile strength of the rail is 1300MPa~1420MPa, and the rail head hardness is 415HB~440HB. The high pressure time in the pre-flash stage of continuous flash welding is 40s, and the flash speed is 0.8mm/s; the low pressure time in the flash stage is 50s, and the flash speed is 1.0mm/s; the flash acceleration speed in the accelerated burning stage is 2.1mm/s; the charged upsetting time in the upsetting stage is 0.1s, and the upsetting timing is 1.0s; the rail consumption in the forging stage is 5.0mm, the forging time is 1.0s, and the average speed is 0.60mm/s. After welding, the rail passes through a special quenching device along the longitudinal direction of the rail at a certain running speed. Under the action of compressed air with a specific pressure, the rail welded joint with residual heat from welding is accelerated to cool. The running speed of the rail is 1.0m/s; the total effective quenching length of the residual heat quenching device at the rear end of the welding process is 35m; the length of the independent quenching unit wind box and the air duct is 155mm, the width of the wind box on the top of the rail is 72mm, the inner diameter of the air duct is Φ25mm, the distance between the wind box and the air duct on the side adjacent to the rail surface is 30mm, and a number of air outlets are evenly distributed, the diameter of the air outlet is Φ2mm, and the spacing between the air outlets is 10mm; the pressure value of the compressed air before entering the quenching device is 200kPa. After inspection, the ratio of the hardness of the re-austenitized zone of the rail joint in this comparative example to the hardness of the rail base material is 0.78, which effectively ensures the smoothness of the joint, and the technical indicators meet the standard requirements. At the same time, the microstructure of the standard inspection part in the joint is pearlite, without abnormal structures such as martensite or bainite. The comparative example adopts a lower high pressure time and low pressure time than the patent claims, resulting in a small welding heat input; adopts a higher flash speed at each stage than the patent claims, resulting in an increased rail consumption and a large heat loss; adopts a higher top forging and forging rail consumption than the patent claims, resulting in an increased rail consumption and a large heat loss. In the subsequent air quenching process, the cooling rate is too slow, and the ratio of the hardness of the joint re-austenitization zone to the hardness of the rail base material does not meet the standard technical requirements. In the case of the same rail material, the comparative example method cannot achieve the expected effect.
以上是本发明公开的示例性实施例，但是应当注意，在不背离权利要求限定的本发明实施例公开的范围的前提下，可以进行多种改变和修改。根据这里描述的公开实施例的方法权利要求的功能、步骤和/或动作不需以任何特定顺序执行。此外，尽管本发明实施例公开的元素可以以个体形式描述或要求，但除非明确限制为单数，也可以理解为多个。The above are exemplary embodiments disclosed in the present invention, but it should be noted that various changes and modifications may be made without departing from the scope disclosed in the embodiments of the present invention as defined in the claims. The functions, steps and/or actions of the method claims according to the disclosed embodiments described herein do not need to be performed in any particular order. In addition, although the elements disclosed in the embodiments of the present invention may be described or required in individual form, they may also be understood as multiple unless explicitly limited to the singular.
应当理解的是，在本文中使用的，除非上下文清楚地支持例外情况， 单数形式“一个”旨在也包括复数形式。还应当理解的是，在本文中使用的“和/或”是指包括一个或者一个以上相关联地列出的项目的任意和所有可能组合。It should be understood that as used herein, unless the context clearly supports an exception, The singular forms "a", "an", and "an" are intended to include the plural forms as well. It should also be understood that "and/or" used herein is intended to include any and all possible combinations of one or more of the associated listed items.
上述本发明实施例公开实施例序号仅仅为了描述，不代表实施例的优劣。The serial numbers of the embodiments disclosed in the above embodiments of the present invention are only for description and do not represent the advantages or disadvantages of the embodiments.
所属领域的普通技术人员应当理解：以上任何实施例的讨论仅为示例性的，并非旨在暗示本发明实施例公开的范围(包括权利要求)被限于这些例子；在本发明实施例的思路下，以上实施例或者不同实施例中的技术特征之间也可以进行组合，并存在如上的本发明实施例的不同方面的许多其它变化，为了简明它们没有在细节中提供。因此，凡在本发明实施例的精神和原则之内，所做的任何省略、修改、等同替换、改进等，均应包含在本发明实施例的保护范围之内。 A person skilled in the art should understand that the discussion of any of the above embodiments is only exemplary and is not intended to imply that the scope of the disclosure of the embodiments of the present invention (including the claims) is limited to these examples; under the concept of the embodiments of the present invention, the technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the above embodiments of the present invention, which are not provided in detail for the sake of simplicity. Therefore, any omissions, modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the embodiments of the present invention should be included in the protection scope of the embodiments of the present invention.

Claims (10)

  1. 一种提高过共析钢轨接头再奥氏体化区硬度的方法，其特征在于，包括：A method for improving the hardness of a hypereutectoid rail joint re-austenitization zone, characterized by comprising:
    (1)将过共析钢轨接头进行前端处理；(1) Perform front-end processing on the hypereutectoid rail joint;
    (2)将过共析钢轨接头进行闪光焊接处理，焊接包括预闪光、闪光、加速烧化、顶锻以及锻造阶段；(2) flash welding the hypereutectoid rail joint, including pre-flash, flash, accelerated burning, top forging and forging stages;
    (3)对焊接后具有焊接余热的所述过共析钢轨接头进行周向淬火处理，所述周向淬火处理包括分别对轨头顶部、轨头侧部以及轨头下颚均匀喷吹压缩空气进行加速冷却；(3) performing circumferential quenching treatment on the hypereutectoid rail joint having residual heat after welding, wherein the circumferential quenching treatment comprises uniformly spraying compressed air on the top, side and lower jaw of the rail head to accelerate cooling;
    (4)将过共析钢轨接头进行后端处理；(4) performing back-end processing on the hypereutectoid rail joint;
    其中，每一个处理工序之间通过传送辊道连接以形成生产线，所述过共析钢轨接头通过所述传送辊道带动依次进入每一个所述处理工序中，所述周向淬火处理时的淬火长度为10～50m。Among them, each processing step is connected by a conveying roller to form a production line, and the hypereutectoid rail joint is driven by the conveying roller to enter each processing step in turn, and the quenching length during the circumferential quenching treatment is 10 to 50m.
  2. 根据权利要求1所述的提高过共析钢轨接头再奥氏体化区硬度的方法，其特征在于，步骤(2)的焊接处理包括：The method for improving the hardness of the re-austenitized zone of a hypereutectoid rail joint according to claim 1 is characterized in that the welding process in step (2) comprises:
    所述预闪光阶段的高压时间为45s～65s，闪光速度为0.1mm/s～0.6mm/s；The high-voltage time of the pre-flash stage is 45s to 65s, and the flash speed is 0.1mm/s to 0.6mm/s;
    所述闪光阶段的低压时间为80s～140s，闪光速度为0.1mm/s～0.6mm/s；The low pressure time of the flashing stage is 80s to 140s, and the flashing speed is 0.1mm/s to 0.6mm/s;
    所述加速烧化阶段的闪光加速速度为0.5mm/s～2.0mm/s；The flash acceleration speed in the accelerated burning stage is 0.5 mm/s to 2.0 mm/s;
    所述顶锻阶段的带电顶锻时间为0.1s～2.0s，顶锻计时为1.0s～3.0s；The charged upsetting time in the upsetting stage is 0.1s to 2.0s, and the upsetting timing is 1.0s to 3.0s;
    所述锻造阶段钢轨消耗量为2.0mm～4.0mm，锻造时间为1.5s～3.0s，平均速度为0.60mm/s～2.60mm/s。The rail consumption in the forging stage is 2.0 mm to 4.0 mm, the forging time is 1.5 s to 3.0 s, and the average speed is 0.60 mm/s to 2.60 mm/s.
  3. 根据权利要求1所述的提高过共析钢轨接头再奥氏体化区硬度的方法，其特征在于，对所述轨头顶部、所述轨头侧部以及所述轨头下颚均匀喷吹压力值为50kPa～300kPa的所述压缩空气。The method for improving the hardness of the re-austenitizing zone of a hypereutectoid rail joint according to claim 1 is characterized in that the compressed air with a pressure value of 50 kPa to 300 kPa is uniformly sprayed on the top of the rail head, the side of the rail head and the lower jaw of the rail head.
  4. 根据权利要求1所述的提高过共析钢轨接头再奥氏体化区硬度的方法，其特征在于，设置所述传送辊道的传送速度为0.2m/s～2.5m/s。 The method for improving the hardness of the re-austenitizing zone of the hypereutectoid rail joint according to claim 1 is characterized in that the conveying speed of the conveying roller is set to 0.2m/s to 2.5m/s.
  5. 根据权利要求1所述的提高过共析钢轨接头再奥氏体化区硬度的方法，其特征在于，过共析钢轨的主要化学成分包括：The method for improving the hardness of the re-austenitization zone of a hypereutectoid rail joint according to claim 1 is characterized in that the main chemical components of the hypereutectoid rail include:
    碳的质量分数处于0.90％～1.20％、硅的质量分数处于0.10％～1.00％、锰的质量分数处于0.60％～1.50％、磷和硫的质量分数均不超过0.020％，铬的质量分数不超过0.3％以及钒的质量分数不超过0.01％。The mass fraction of carbon is between 0.90% and 1.20%, the mass fraction of silicon is between 0.10% and 1.00%, the mass fraction of manganese is between 0.60% and 1.50%, the mass fractions of phosphorus and sulfur do not exceed 0.020%, the mass fraction of chromium does not exceed 0.3%, and the mass fraction of vanadium does not exceed 0.01%.
  6. 根据权利要求1所述的提高过共析钢轨接头再奥氏体化区硬度的方法，其特征在于，所述过共析钢轨的最小抗拉强度为1200MPa，所述过共析钢轨轨头的最小硬度为400HB。The method for improving the hardness of the re-austenization zone of the hypereutectoid rail joint according to claim 1 is characterized in that the minimum tensile strength of the hypereutectoid rail is 1200 MPa, and the minimum hardness of the hypereutectoid rail head is 400 HB.
  7. 一种如上述权利要求任一项所述的方法中使用的提高过共析钢轨接头再奥氏体化区硬度的装置，所述装置用于周向淬火处理，其特征在于，包括：A device for increasing the hardness of the re-austenitized zone of a hypereutectoid rail joint as used in the method according to any one of the preceding claims, the device being used for circumferential quenching treatment, characterized in that it comprises:
    传送辊道；Conveyor rollers;
    沿所述传送辊道方向依次排列的多个淬火单元，每一个所述淬火单元包括轨头风盒、对称分布于轨头侧面的第一风管以及对称分布于轨头下颚的第二风管，所述风盒与所述风管的纵向长度一致，并且与其相邻钢轨表面的距离相同，所述风盒与所述风管上均匀分布多个出气孔以向所述钢轨接头喷吹压缩空气。A plurality of quenching units are arranged in sequence along the direction of the conveying roller, each of the quenching units comprises a rail head wind box, a first wind duct symmetrically distributed on the side of the rail head, and a second wind duct symmetrically distributed on the lower jaw of the rail head, the wind box is consistent with the longitudinal length of the wind duct, and has the same distance from the surface of the adjacent rail, and a plurality of air outlets are evenly distributed on the wind box and the wind duct to spray compressed air to the rail joint.
  8. 根据权利要求7所述的提高过共析钢轨接头再奥氏体化区硬度的装置，其特征在于，每一个所述淬火单元包括一个轨头风盒、对称分布于轨头侧面的两个所述第一风管以及对称分布于轨头下颚的两个所述第二风管，每一个所述淬火单元独立调控压缩空气压力值。The device for improving the hardness of the re-austenization zone of the hypereutectoid rail joint according to claim 7 is characterized in that each of the quenching units includes a rail head air box, two of the first air ducts symmetrically distributed on the side of the rail head, and two of the second air ducts symmetrically distributed on the lower jaw of the rail head, and each of the quenching units independently adjusts the compressed air pressure value.
  9. 根据权利要求8所述的提高过共析钢轨接头再奥氏体化区硬度的装置，其特征在于，所述压缩空气进入淬火装置前的压力值为50kPa～300kPa。The device for increasing the hardness of the re-austenitizing zone of a hypereutectoid rail joint according to claim 8 is characterized in that the pressure of the compressed air before entering the quenching device is 50 kPa to 300 kPa.
  10. 根据权利要求7所述的提高过共析钢轨接头再奥氏体化区硬度的装置，其特征在于，所述多个淬火单元组成的所述淬火装置的总长度为10m～50m，所述风盒宽度≥70mm，所述风盒和所述风管的长度≥150mm，所述风管的直径为Φ25mm～Φ30mm，所述风盒和所述风管与其相邻所述钢轨表面的距离为20mm～40mm，所述出气孔直径为Φ1mm～Φ3mm，所述出气孔之间的间距为5mm～15mm。 The device for improving the hardness of the re-austenitizing zone of the hypereutectoid rail joint according to claim 7 is characterized in that the total length of the quenching device composed of the multiple quenching units is 10m to 50m, the width of the wind box is ≥70mm, the length of the wind box and the air duct is ≥150mm, the diameter of the air duct is Φ25mm to Φ30mm, the distance between the wind box and the air duct and the adjacent rail surface is 20mm to 40mm, the diameter of the air outlet is Φ1mm to Φ3mm, and the spacing between the air outlets is 5mm to 15mm.
PCT/CN2023/093531 2022-11-03 2023-05-11 Method and device for improving hardness of reaustenitizing area of hypereutectoid steel rail joint WO2024093182A1 (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
AU2023216732A AU2023216732A1 (en) 2022-11-03 2023-05-11 A method and device for increasing hardness of re-austenitizing zone of hypereutectoid rail joint

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
CN202211368264.3A CN115679079A (en) 2022-11-03 2022-11-03 Method and device for improving hardness of hypereutectoid steel rail joint re-austenitizing area
CN202211368264.3 2022-11-03

Publications (1)

Publication Number Publication Date
WO2024093182A1 true WO2024093182A1 (en) 2024-05-10

Family

ID=85048726

Family Applications (1)

Application Number Title Priority Date Filing Date
PCT/CN2023/093531 WO2024093182A1 (en) 2022-11-03 2023-05-11 Method and device for improving hardness of reaustenitizing area of hypereutectoid steel rail joint

Country Status (3)

Country Link
CN (1) CN115679079A (en)
AU (1) AU2023216732A1 (en)
WO (1) WO2024093182A1 (en)

Families Citing this family (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN115679079A (en) * 2022-11-03 2023-02-03 攀钢集团攀枝花钢铁研究院有限公司 Method and device for improving hardness of hypereutectoid steel rail joint re-austenitizing area

Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2415885A1 (en) * 2009-03-30 2012-02-08 Nippon Steel Corporation Method of cooling welded rail section, device for cooling welded rail section, and welded rail joint
CN109055708A (en) * 2018-08-20 2018-12-21 攀钢集团攀枝花钢铁研究院有限公司 A kind of eutectoid rail and hypereutectoid steel rail weld joint heat treatment method
US20190061041A1 (en) * 2017-08-31 2019-02-28 Pangang Group Research Institute Co., Ltd. Mobile flash butt welding method for 136re+ss heat-treated rail
CN113414480A (en) * 2021-07-23 2021-09-21 攀钢集团攀枝花钢铁研究院有限公司 Method for eliminating overburning defect of mobile flash welding head of hypereutectoid steel rail of 75kg/m
CN115488484A (en) * 2022-11-03 2022-12-20 攀钢集团攀枝花钢铁研究院有限公司 Method for improving hardness of normalizing region of hypereutectoid steel rail flash welding head
CN115679079A (en) * 2022-11-03 2023-02-03 攀钢集团攀枝花钢铁研究院有限公司 Method and device for improving hardness of hypereutectoid steel rail joint re-austenitizing area

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP2415885A1 (en) * 2009-03-30 2012-02-08 Nippon Steel Corporation Method of cooling welded rail section, device for cooling welded rail section, and welded rail joint
US20190061041A1 (en) * 2017-08-31 2019-02-28 Pangang Group Research Institute Co., Ltd. Mobile flash butt welding method for 136re+ss heat-treated rail
CN109055708A (en) * 2018-08-20 2018-12-21 攀钢集团攀枝花钢铁研究院有限公司 A kind of eutectoid rail and hypereutectoid steel rail weld joint heat treatment method
CN113414480A (en) * 2021-07-23 2021-09-21 攀钢集团攀枝花钢铁研究院有限公司 Method for eliminating overburning defect of mobile flash welding head of hypereutectoid steel rail of 75kg/m
CN115488484A (en) * 2022-11-03 2022-12-20 攀钢集团攀枝花钢铁研究院有限公司 Method for improving hardness of normalizing region of hypereutectoid steel rail flash welding head
CN115679079A (en) * 2022-11-03 2023-02-03 攀钢集团攀枝花钢铁研究院有限公司 Method and device for improving hardness of hypereutectoid steel rail joint re-austenitizing area

Also Published As

Publication number Publication date
AU2023216732A1 (en) 2024-05-23
CN115679079A (en) 2023-02-03

Similar Documents

Publication Publication Date Title
CN103898310B (en) A kind of post weld heat treatment method of bainite rail welding point
CN107520529B (en) The method of the mobile Flash Butt Welding of 136RE+SS heat-treated rail
WO2024093182A1 (en) Method and device for improving hardness of reaustenitizing area of hypereutectoid steel rail joint
CN104862466B (en) Method for postweld heat treatment on hyper-eutectoid steel rail welding connector
JP4906651B2 (en) Heat treatment method for steel rail and heat treatment apparatus used therefor
US20120152410A1 (en) Method And Device for Energy-Efficient Hot Forming
CN111020149B (en) Bearing steel bar rolling process
JP2007044764A (en) Hot forging equipment
CN108823394B (en) Steel rail postweld heat treatment method
CN1054642C (en) Process for heat treatment of steel rail
CN103205551A (en) Thermal treatment processing method of thrust wheel
CN110918642A (en) Production control method for improving bending degree of 42CrMo bar
CN112251592A (en) Construction method for heat treatment of dissimilar steel rail flash welded joint
CN103898303A (en) Heat treatment method of turnout rail and turnout rail
CN112143877A (en) Hot-rolled high-strength steel full-continuous heat treatment production system and method
CN104087836A (en) Vanadium-chromium micro-alloyed superfine pearlite steel rail
CN109676227A (en) 900MPa high intensity loop chain pulsed flashing butt welding technique
AU2021215140B2 (en) POST-WELD HEAT TREATMENT METHOD FOR 1,300MPa-LEVEL LOW-ALLOY HEAT TREATED STEEL RAIL
WO2018147755A1 (en) Method for producing and heat treating rail strings and facility for the implementation thereof
CN109777946A (en) A kind of production system of strip continuous heat
CN115488484B (en) Method for improving hardness of normalizing region of flash welding head of hypereutectoid steel rail
CN104212965A (en) Method for online laser broadband quenching on surface of steel rail
CN115044764B (en) Manufacturing method for on-line heat treatment of hundred-meter steel rail under low-temperature condition
JP3900801B2 (en) Heat treatment equipment for seamless steel pipes
CN115488481B (en) Method for reducing width of spheroidizing annealing zone of hypereutectoid steel rail joint

Legal Events

Date Code Title Description
ENP Entry into the national phase

Ref document number: 2023216732

Country of ref document: AU

Date of ref document: 20230511

Kind code of ref document: A

REG Reference to national code

Ref country code: BR

Ref legal event code: B01A

Ref document number: 112023016731

Country of ref document: BR

121 Ep: the epo has been informed by wipo that ep was designated in this application

Ref document number: 23884124

Country of ref document: EP

Kind code of ref document: A1