CN115369229A - Production control method for improving flatness of turnout steel rail after on-line heat treatment quenching - Google Patents
Production control method for improving flatness of turnout steel rail after on-line heat treatment quenching Download PDFInfo
- Publication number
- CN115369229A CN115369229A CN202211110868.8A CN202211110868A CN115369229A CN 115369229 A CN115369229 A CN 115369229A CN 202211110868 A CN202211110868 A CN 202211110868A CN 115369229 A CN115369229 A CN 115369229A
- Authority
- CN
- China
- Prior art keywords
- steel rail
- rail
- cooling
- heat treatment
- controlled
- Prior art date
- Legal status (The legal status 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 status listed.)
- Pending
Links
- 229910000831 Steel Inorganic materials 0.000 title claims abstract description 172
- 239000010959 steel Substances 0.000 title claims abstract description 172
- 238000010438 heat treatment Methods 0.000 title claims abstract description 58
- 238000010791 quenching Methods 0.000 title claims abstract description 22
- 230000000171 quenching effect Effects 0.000 title claims abstract description 22
- 238000000195 production control method Methods 0.000 title claims abstract description 14
- 238000001816 cooling Methods 0.000 claims abstract description 138
- 238000000034 method Methods 0.000 claims description 22
- 230000008569 process Effects 0.000 claims description 19
- 238000004519 manufacturing process Methods 0.000 claims description 13
- 239000003595 mist Substances 0.000 claims description 7
- 239000002826 coolant Substances 0.000 claims description 6
- 238000005096 rolling process Methods 0.000 claims description 6
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 6
- 239000000126 substance Substances 0.000 claims description 5
- 229910052799 carbon Inorganic materials 0.000 claims description 4
- 239000012535 impurity Substances 0.000 claims description 4
- 238000005452 bending Methods 0.000 abstract description 3
- 229910001562 pearlite Inorganic materials 0.000 description 5
- 229910001566 austenite Inorganic materials 0.000 description 3
- 238000011161 development Methods 0.000 description 3
- 238000002474 experimental method Methods 0.000 description 3
- 239000002184 metal Substances 0.000 description 3
- 229910052751 metal Inorganic materials 0.000 description 3
- 239000000203 mixture Substances 0.000 description 3
- 230000002159 abnormal effect Effects 0.000 description 2
- 230000009466 transformation Effects 0.000 description 2
- 241000446313 Lamella Species 0.000 description 1
- 238000003723 Smelting Methods 0.000 description 1
- 238000005299 abrasion Methods 0.000 description 1
- 229910001563 bainite Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 125000004432 carbon atom Chemical group C* 0.000 description 1
- 230000003749 cleanliness Effects 0.000 description 1
- 238000009749 continuous casting Methods 0.000 description 1
- 238000009792 diffusion process Methods 0.000 description 1
- 238000009826 distribution Methods 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 230000017525 heat dissipation Effects 0.000 description 1
- 239000011229 interlayer Substances 0.000 description 1
- 229910000734 martensite Inorganic materials 0.000 description 1
- 230000005012 migration Effects 0.000 description 1
- 238000013508 migration Methods 0.000 description 1
- 238000012986 modification Methods 0.000 description 1
- 230000004048 modification Effects 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000010008 shearing Methods 0.000 description 1
- 238000004781 supercooling Methods 0.000 description 1
- 238000009849 vacuum degassing Methods 0.000 description 1
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
- C21D9/00—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor
- C21D9/04—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rails
- C21D9/06—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rails with diminished tendency to become wavy
-
- 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
- C21D11/00—Process control or regulation for heat treatments
- C21D11/005—Process control or regulation for heat treatments for cooling
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention discloses a production control method for improving the flatness of a turnout steel rail after quenching in online heat treatment, which applies a certain cooling speed to each part of the steel rail to keep each part of the steel rail in a certain temperature difference range, so that the steel rail can keep ideal flatness in a heat treatment unit and a heat treatment unit, and the steel rail can also keep better flatness after being slowly cooled to room temperature after being taken out of the heat treatment unit. According to the invention, the cooling strength and the temperature difference of the rail head, the rail bottom, the left end and the right end of the steel rail are reasonably controlled, so that the bending control of the turnout steel rail after heat treatment is in an ideal range, the steel rail is straightened by adopting light pressure after being cooled, and the final mechanical property and the straightness of the steel rail meet the technical requirements of the TB/T2344-2012 standard.
Description
Technical Field
The invention relates to the field of steel rail production and application, in particular to a production control method for improving the flatness of a turnout steel rail subjected to on-line heat treatment after quenching.
Background
The rise and development of high-speed and heavy-duty railways in various countries in the world enable the running speed and the axle weight of a train to be greatly increased, and the increase of the axle weight of the train inevitably causes the increase of wheel rail contact stress and the internal shearing stress of a rail head, so that the service environment of the steel rail is deteriorated, the contact fatigue damage is increased, and particularly the abrasion, stripping and chipping, crushing, nuclear damage and the like of the steel rail in a curve and large-slope section are increased year by year, therefore, the development and planning of the railway in China are provided, and the strength, the straightness and the cleanliness of the steel rail are improved to meet the development requirements of the railway.
At present, the on-line heat treatment is the most effective method for improving the strength of the steel rail, namely, the steel rail in an austenite state is subjected to accelerated cooling, and the air mist cooling method is adopted, so that the metallographic structure of the rail head of the steel rail is a fine lamellar pearlite structure. In the heat treatment process of the steel rail, the section shape of the steel rail is uneven, the metal quantity of the rail bottom is less than that of the rail head, and the metal quantity of the left side and the right side of the steel rail is different, so that the heat dissipation of all parts of the steel rail is uneven in the rapid cooling process, if the cooling strength distribution of the rail head, the rail bottom and the left and the right ends of the steel rail is unreasonable, the steel rail is easy to bend after the heat treatment process and the heat treatment are finished, and therefore the steel rail needs to be kept straight as far as possible after the on-line heat treatment process, the follow-up straightening pressure can be reduced, and the residual stress of the steel rail is reduced.
Disclosure of Invention
In order to solve the technical problems, the invention aims to provide a production control method for improving the flatness of a turnout steel rail subjected to online heat treatment after quenching, which can ensure that the flatness of the turnout steel rail subjected to heat treatment is excellent, and the mechanical property of the steel rail meets the standard heat treatment process system.
In order to solve the technical problems, the invention adopts the following technical scheme:
the invention relates to a production control method for improving flatness of turnout steel rails after quenching in online heat treatment, which comprises the following steps:
after rolling, the steel rail enters an online heat treatment production line for accelerated cooling, the cooling medium is water mist cooling, the temperature of the steel rail entering a quenching line is 730-780 ℃, the cooling speed of rail heads of a cooling 1 section and a cooling 2 section is controlled at 6-7 ℃/s, the cooling speed of a rail bottom is controlled at 2.5-3.5 ℃/s, the cooling speed of the left side of the steel rail is controlled at 6-7 ℃/s, the cooling speed of the right side of the steel rail is controlled at 6.5-5.5 ℃/s, after the steel rail is rapidly cooled by the cooling 1 section and the cooling 2 section, the temperature of the rail head reaches 580-630 ℃, and the temperature of the rail bottom is 620-670 ℃;
then, continuously and rapidly cooling the steel rail in a cooling 3 section and a cooling 4 section, wherein the cooling speed is reduced, the cooling speed of a rail head is controlled to be 2-3 ℃/s, the cooling speed of a rail bottom is controlled to be 1-1.5 ℃/s, the cooling speed of the left side of the steel rail is controlled to be 2-3 ℃/s, the cooling speed of the right side of the steel rail is controlled to be 2-2.5 ℃/s, the steel rail is taken out of an online heat treatment unit after the cooling 3 section and the cooling 4 section are finished, the temperature of the rail head is controlled to be 540-560 ℃, and the temperature of the rail bottom is controlled to be 610-640 ℃;
the steel rail is taken out of the quenching line and naturally cooled to room temperature, the whole steel rail is basically ensured to be straight or warped to a certain degree towards the rail head direction, and the upwarping height of the end part of the steel rail with the length of 100m is within the range of 0-40 mm; the steel rail is straightened by adopting light pressure.
Further, the chemical components of the steel rail in percentage by mass comprise: 0.75 to 0.80 percent of C; 0.60 to 0.80 percent of Si; 0.90 to 1.00 percent of Mn; p is less than or equal to 0.025 percent; s is less than or equal to 0.025 percent; v0.06-0.12%, and the balance of Fe and inevitable impurities.
Further, the final mechanical properties of the steel rail are as follows: the tensile strength Rm is more than or equal to 1180MPa, the elongation A after fracture is more than or equal to 10 percent, the hardness of the top surface center line of the steel rail is 340-400 HBW, and the residual stress of the rail bottom is less than or equal to 250MPa.
Further, the straightening process comprises the following steps: 2 rollers of 20-24mm, 4 rollers of 11-13mm, 6 rollers of 11-13mm and 8 rollers of 2-4 mm.
Compared with the prior art, the invention has the beneficial technical effects that:
in order to prevent the steel rail from bending caused by overlarge temperature difference in the heat treatment process of the steel rail, a certain cooling speed is applied to each part of the steel rail, so that each part of the steel rail keeps a certain temperature difference range, the steel rail can keep ideal flatness both in a heat treatment unit and a heat treatment unit, and the steel rail can keep good flatness after being slowly cooled to room temperature after being discharged from the heat treatment unit. The higher the straightness before the steel rail is straightened, the smaller the pressure value of each roller in the straightening process is, and the residual stress at the bottom of the steel rail can be directly reduced by adopting light pressure straightening.
Detailed Description
The steel rail production method comprises the following steps: converter smelting, LF refining, vacuum degassing, continuous casting, billet heating, rolling and other processes, but the steps are not particularly limited in the patent and are carried out according to a normal steel rail production process system. The steel rail after-rolling online heat treatment process and the straightening process are researched, the principle of the steel rail after-rolling accelerated cooling is that the steel rail after-rolling residual heat is utilized for accelerated cooling, the supercooling degree of austenite to pearlite transformation is increased, the pearlite transformation temperature is reduced, and the migration distance of carbon atoms in austenite is reduced, so that pearlite with finer interlayer spacing is obtained, the strength and the hardness of the steel rail are improved, and the wear resistance of the steel rail is improved. In the process of accelerating cooling of the steel rail, the cooling speed of the rail head of the steel rail directly determines the mechanical property result of the steel rail after final heat treatment, and when the cooling speed is too low, a pearlite structure with fine lamella spacing is difficult to obtain, so that the strength and the hardness are not enough; when the cooling speed is too high, the diffusion rate of carbide is reduced, so that abnormal structures such as bainite and martensite are formed, the cooling speed of the rail head of the steel rail is controlled within a certain range, and the mechanical property of the rail head after heat treatment meets the standard requirement. The metal amount of each part of the steel rail is different, in order to prevent the steel rail from being bent due to overlarge temperature difference in the heat treatment process of the steel rail, a certain cooling speed is applied to each part of the steel rail, each part of the steel rail is enabled to keep a certain temperature difference range, the steel rail can keep ideal flatness in the heat treatment unit and the heat treatment unit, and the steel rail can also keep good flatness after being slowly cooled to room temperature after being discharged from the heat treatment unit. The higher the straightness before the steel rail is straightened, the smaller the pressure value of each roller in the straightening process is, and the residual stress at the bottom of the steel rail can be directly reduced by adopting light pressure straightening.
The present invention is described in detail below:
a production control method for improving the flatness of a turnout steel rail subjected to online heat treatment after quenching comprises the following chemical components in percentage by mass: 0.75 to 0.80 percent of C; 0.60 to 0.80 percent of Si; 0.90 to 1.00 percent of Mn; p is less than or equal to 0.025 percent; s is less than or equal to 0.025 percent; v is 0.06 to 0.12 percent, and the balance is Fe and inevitable impurities; the specific control process is as follows:
the steel rail is rolled and then enters an online heat treatment production line for accelerated cooling, the cooling medium is water mist cooling, the temperature of the steel rail entering a quenching line is 730-780 ℃, the cooling speed of the rail head of the cooling 1 section and the cooling speed of the rail head of the cooling 2 section are controlled at 6-7 ℃/s, the cooling speed of the rail bottom is controlled at 2.5-3.5 ℃/s, the cooling speed of the left side of the steel rail is controlled at 6-7 ℃/s, the cooling speed of the right side of the steel rail is controlled at 6.5-5.5 ℃/s, after the steel rail is rapidly cooled by the cooling 1 section and the cooling 2 section, the temperature of the rail head reaches 580-630 ℃, and the temperature of the rail bottom is 620-670 ℃. Then the steel rail is continuously and rapidly cooled in a cooling 3 section and a cooling 4 section, the cooling speed is reduced, the cooling speed of the rail head is controlled to be 2-3 ℃/s, the cooling speed of the rail bottom is controlled to be 1-1.5 ℃/s, the cooling speed of the left side of the steel rail is controlled to be 2-3 ℃/s, the cooling speed of the right side of the steel rail is controlled to be 2-2.5 ℃/s, the steel rail is taken out of an online heat treatment unit after the cooling 3 section and the cooling 4 section are finished, the temperature of the rail head is controlled to be 540-560 ℃, and the temperature of the rail bottom is controlled to be 610-640 ℃. The steel rail is naturally cooled to room temperature after being taken out of the quenching line, the whole steel rail is basically kept straight or is warped to a certain degree towards the rail head direction, and the upwarping height of the end part of the steel rail with the length of 100m is within the range of 0-40 mm. The steel rail is straightened by adopting light pressure, and the straightening process is 2 rollers 20-24,4 roller 11-13,6 roller 11-13,8 roller 2-4. The final mechanical property of the steel rail, tensile strength Rm is more than or equal to 1180MPa, elongation A after fracture is more than or equal to 10 percent, the hardness of the top surface center line of the steel rail is 340-400 HBW, and the residual stress of the bottom of the steel rail is less than or equal to 250MPa.
The present invention will be described in further detail with reference to specific embodiments thereof so that the present invention may be more clearly understood.
The production method is used for heat-treating the steel rail with a specific component range, can effectively ensure that the mechanical properties of the steel rail, such as strength, hardness and the like, meet the requirements after heat treatment, has better steel rail straightness and has smaller residual stress after light pressure straightening. The specific heat-treated steel rail comprises the following chemical components in percentage by mass: 0.75 to 0.80 percent of C; 0.60 to 0.80 percent of Si; 0.90 to 1.00 percent of Mn; p is less than or equal to 0.025 percent; s is less than or equal to 0.025 percent; v0.06-0.12%, and the balance Fe and inevitable impurities. 4 sets of heat treatment on-line heat treatment experiments were carried out using this composition range, and the results are shown in Table 1. The rest of the production process of the steel rail is carried out according to a conventional production method.
TABLE 1 chemical composition and Performance results of on-line Heat treatment experiment rails
According to the results of Table 1, it can be seen that the mechanical properties of the steel rails of examples 2 and 3, which are in the range of the specific components of the present invention, can meet the requirements of the standard technical requirements after the steel rails are subjected to the on-line heat treatment, while the metallographic structure of the steel rail of example 1 is abnormal after the steel rails are subjected to the on-line heat treatment, and the steel rail of example 4 does not meet the standard technical requirements of the tensile strength of 1180MPa or more and the hardness of 340-400 HB. Therefore, the rail base cooling rate was adjusted to improve the straightness of the rail taken out of the heat treatment line by using the rail composition range in example 2, and 3 on-line rail heat treatment experiments were performed and straightening was performed as in example 5, example 6, and example 7, specifically as follows:
example 5:
the steel rail is rolled and then enters an online heat treatment production line for accelerated cooling, the cooling medium is water mist cooling, the temperature of the steel rail entering a quenching line is 750 ℃, the cooling speed of the rail head of the cooling 1 section and the cooling speed of the rail head of the cooling 2 section are controlled at 6.6 ℃/s, the cooling speed of the rail bottom is controlled at 2 ℃/s, the cooling speed of the left side of the steel rail is controlled at 6.6 ℃/s, the cooling speed of the right side of the steel rail is controlled at 6 ℃/s, the temperature of the rail head reaches 615 ℃ and the temperature of the rail bottom is 687 ℃ after the steel rail is rapidly cooled by the cooling 1 section and the cooling 2 section. And then continuously and rapidly cooling the steel rail in a cooling 3 section and a cooling 4 section, wherein the cooling speed is reduced, the cooling speed of a rail head is controlled at 2.6 ℃/s, the cooling speed of a rail bottom is controlled at 0.7 ℃/s, the cooling speed of the left side of the steel rail is controlled at 2.5 ℃/s, the cooling speed of the right side of the steel rail is controlled at 2.1 ℃/s, the steel rail is taken out of an online heat treatment unit after the cooling 3 section and the cooling 4 section are finished, the temperature of the rail head is controlled at 548 ℃, and the temperature of the rail bottom is controlled at 672 ℃. The steel rail is naturally cooled to room temperature after exiting the quenching line, the whole steel rail is basically flat, the end of the steel rail is warped towards the rail head, and the upturned height of the end part of the steel rail with the length of 100m is 62mm. The steel rail enters a straightening machine for straightening, the straightening technological parameters are 2 rollers 24mm,4 rollers 13mm,6 rollers 11mm and 8 rollers 3mm, the straightness of the straightened steel rail meets the standard technical requirements, and the residual stress at the bottom of the rail is detected to be 165MPa.
Example 6:
the steel rail is rolled and then enters an online heat treatment production line for accelerated cooling, the cooling medium is water mist for cooling, the temperature of the steel rail entering a quenching line is 748 ℃, the cooling speed of rail heads of a cooling section 1 and a cooling section 2 is controlled at 6.6 ℃/s, the cooling speed of a rail bottom is controlled at 3 ℃/s, the cooling speed of the left side of the steel rail is controlled at 6.6 ℃/s, the cooling speed of the right side of the steel rail is controlled at 6.1 ℃/s, after the steel rail is rapidly cooled by the cooling section 1 and the cooling section 2, the temperature of the rail head reaches 589 ℃, and the temperature of the rail bottom is 628 ℃. And then continuously and rapidly cooling the steel rail in a cooling 3 section and a cooling 4 section, wherein the cooling speed is reduced, the cooling speed of a rail head is controlled at 2.6 ℃/s, the cooling speed of a rail bottom is controlled at 1.3 ℃/s, the cooling speed of the left side of the steel rail is controlled at 2.6 ℃/s, the cooling speed of the right side of the steel rail is controlled at 2.3 ℃/s, the steel rail is taken out of an online heat treatment unit after the cooling 3 section and the cooling 4 section are finished, the temperature of the rail head is controlled at 542 ℃, and the temperature of the rail bottom is controlled at 626 ℃. The steel rail is naturally cooled to room temperature after exiting the quenching line, the whole steel rail is basically flat, the rail end of the steel rail is warped to a certain degree towards the rail head, and the upturned height of the end part of the steel rail with the length of 100m is within 19 mm. The steel rail enters a straightening machine for straightening, the straightening technological parameters are 2mm for rollers 22mm, 4mm for rollers 12mm, 6 mm for rollers 11mm and 8mm for rollers 2mm, the straightness of the straightened steel rail meets the standard technical requirements, and the residual stress of the rail bottom is detected to be 85MPa.
Example 7:
the steel rail is rolled and then enters an online heat treatment production line for accelerated cooling, the cooling medium is water mist cooling, the temperature of the steel rail entering a quenching line is 752 ℃, the cooling speed of the rail head of the cooling 1 section and the cooling speed of the rail head of the cooling 2 section are controlled at 6.5 ℃/s, the cooling speed of the rail bottom is controlled at 4 ℃/s, the cooling speed of the left side of the steel rail is controlled at 6.5 ℃/s, the cooling speed of the right side of the steel rail is controlled at 6 ℃/s, after the steel rail is rapidly cooled by the cooling 1 section and the cooling 2 section, the temperature of the rail head reaches 612 ℃, and the temperature of the rail bottom is 582 ℃. And then, continuously and rapidly cooling the steel rail in a cooling 3 section and a cooling 4 section, wherein the cooling speed is reduced, the cooling speed of a rail head is controlled at 2.5 ℃/s, the cooling speed of a rail bottom is controlled at 1.8 ℃/s, the cooling speed of the left side of the steel rail is controlled at 2.5 ℃/s, the cooling speed of the right side of the steel rail is controlled at 2.2 ℃/s, the steel rail is taken out of an online heat treatment unit after the cooling 3 section and the cooling 4 section are finished, the temperature of the rail head is controlled at 558 ℃ at the moment, and the temperature of the rail bottom is controlled at 565 ℃. The steel rail is naturally cooled to room temperature after exiting the quenching line, the whole steel rail is basically flat and straight, the end of the steel rail is warped to a certain degree towards the rail bottom, and the height of the downward warping of the end part of the steel rail with the length of 100m is 28mm. The steel rail enters a straightening machine for straightening, the straightening technological parameters are 2 rollers 24mm,4 rollers 13mm,6 rollers 12mm and 8 rollers 2mm, the straightness of the straightened steel rail meets the standard technical requirements, and the residual stress of the rail bottom is detected to be 190MPa.
According to the comparison of the flatness, the bending height of the end part and the residual stress value after straightening of the steel rail on the online heat treatment production line, the heat treatment process system of the steel rail in the embodiment 6 is carried out according to the process system of the invention, the flatness of the steel rail after online heat treatment is the best, and the residual stress of the rail bottom after straightening is the lowest.
The embodiment shows that the method can effectively improve the flatness of the steel rail after heat treatment and reduce the residual stress of the steel rail bottom on the premise of ensuring the structure and the mechanical property of the heat-treated steel rail.
The above-described embodiments are merely illustrative of the preferred embodiments of the present invention, and do not limit the scope of the present invention, and various modifications and improvements of the technical solutions of the present invention can be made by those skilled in the art without departing from the spirit of the present invention, and the technical solutions of the present invention are within the scope of the present invention defined by the claims.
Claims (4)
1. A production control method for improving flatness of turnout steel rails after on-line heat treatment is characterized by comprising the following steps: the method comprises the following steps:
after rolling, the steel rail enters an online heat treatment production line for accelerated cooling, the cooling medium is water mist for cooling, the temperature of the steel rail entering a quenching line is 730-780 ℃, the cooling speed of the rail head of the cooling 1 section and the cooling speed of the rail head of the cooling 2 section are controlled to be 6-7 ℃/s, the cooling speed of the rail bottom is controlled to be 2.5-3.5 ℃/s, the cooling speed of the left side of the steel rail is controlled to be 6-7 ℃/s, the cooling speed of the right side of the steel rail is controlled to be 6.5-5.5 ℃/s, after the steel rail is rapidly cooled by the cooling 1 section and the cooling 2 section, the temperature of the rail head reaches 580-630 ℃, and the temperature of the rail bottom is 620-670 ℃;
then the steel rail is continuously and rapidly cooled in a cooling 3 section and a cooling 4 section, the cooling speed is reduced, the cooling speed of a rail head is controlled to be 2-3 ℃/s, the cooling speed of a rail bottom is controlled to be 1-1.5 ℃/s, the cooling speed of the left side of the steel rail is controlled to be 2-3 ℃/s, the cooling speed of the right side of the steel rail is controlled to be 2-2.5 ℃/s, the steel rail is taken out of an online heat treatment unit after the cooling 3 section and the cooling 4 section are finished, the temperature of the rail head is controlled to be 540-560 ℃, and the temperature of the rail bottom is controlled to be 610-640 ℃;
the steel rail is taken out of the quenching line and naturally cooled to room temperature, the whole steel rail is basically kept straight or is warped to a certain degree towards the rail head direction, and the upwarping height of the end part of the steel rail with the length of 100m is within the range of 0-40 mm; the steel rail is straightened by adopting light pressure.
2. The production control method for improving the straightness after quenching of the turnout steel rail by online heat treatment according to claim 1, wherein the production control method comprises the following steps: the steel rail comprises the following chemical components in percentage by mass: 0.75 to 0.80 percent of C; 0.60 to 0.80 percent of Si; 0.90 to 1.00 percent of Mn; p is less than or equal to 0.025 percent; s is less than or equal to 0.025 percent; v0.06-0.12%, and the balance Fe and inevitable impurities.
3. The production control method for improving the flatness of the turnout rail after quenching through on-line heat treatment according to claim 2, wherein the production control method comprises the following steps: the final mechanical properties of the steel rail are as follows: the tensile strength Rm is more than or equal to 1180MPa, the elongation A after fracture is more than or equal to 10 percent, the hardness of the top surface center line of the steel rail is 340-400 HBW, and the residual stress of the rail bottom is less than or equal to 250MPa.
4. The production control method for improving the straightness after quenching of the turnout steel rail by online heat treatment according to claim 1, wherein the production control method comprises the following steps: straightening process: 2 rollers of 20-24mm, 4 rollers of 11-13mm, 6 rollers of 11-13mm and 8 rollers of 2-4 mm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211110868.8A CN115369229A (en) | 2022-09-13 | 2022-09-13 | Production control method for improving flatness of turnout steel rail after on-line heat treatment quenching |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211110868.8A CN115369229A (en) | 2022-09-13 | 2022-09-13 | Production control method for improving flatness of turnout steel rail after on-line heat treatment quenching |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN115369229A true CN115369229A (en) | 2022-11-22 |
Family
ID=84071369
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202211110868.8A Pending CN115369229A (en) | 2022-09-13 | 2022-09-13 | Production control method for improving flatness of turnout steel rail after on-line heat treatment quenching |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN115369229A (en) |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103898303A (en) * | 2012-12-31 | 2014-07-02 | 攀钢集团攀枝花钢铁研究院有限公司 | Heat treatment method of turnout rail and turnout rail |
| CN109182715A (en) * | 2018-09-19 | 2019-01-11 | 武汉钢铁有限公司 | Rail burning optimization on line method for controlling planeness |
| CN110358904A (en) * | 2019-05-30 | 2019-10-22 | 邯郸钢铁集团有限责任公司 | The control method of rail shape after rail burning optimization on line |
| WO2021057094A1 (en) * | 2019-09-27 | 2021-04-01 | 武汉钢铁有限公司 | Production method that reduces residual stress of heat-treated steel rail and resulting steel rail |
| CN112877531A (en) * | 2021-01-12 | 2021-06-01 | 包头钢铁（集团）有限责任公司 | Production control method for improving flatness of steel rail after online heat treatment quenching |
| CN113373371A (en) * | 2021-05-21 | 2021-09-10 | 包头钢铁（集团）有限责任公司 | Super-high wear-resistance hypereutectoid pearlite steel rail material added with rare earth and nickel elements |
| CN114058813A (en) * | 2021-11-23 | 2022-02-18 | 包头钢铁（集团）有限责任公司 | Control method of hypereutectoid rare earth steel rail network carbide |
-
2022
- 2022-09-13 CN CN202211110868.8A patent/CN115369229A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103898303A (en) * | 2012-12-31 | 2014-07-02 | 攀钢集团攀枝花钢铁研究院有限公司 | Heat treatment method of turnout rail and turnout rail |
| CN109182715A (en) * | 2018-09-19 | 2019-01-11 | 武汉钢铁有限公司 | Rail burning optimization on line method for controlling planeness |
| CN110358904A (en) * | 2019-05-30 | 2019-10-22 | 邯郸钢铁集团有限责任公司 | The control method of rail shape after rail burning optimization on line |
| WO2021057094A1 (en) * | 2019-09-27 | 2021-04-01 | 武汉钢铁有限公司 | Production method that reduces residual stress of heat-treated steel rail and resulting steel rail |
| CN112877531A (en) * | 2021-01-12 | 2021-06-01 | 包头钢铁（集团）有限责任公司 | Production control method for improving flatness of steel rail after online heat treatment quenching |
| CN113373371A (en) * | 2021-05-21 | 2021-09-10 | 包头钢铁（集团）有限责任公司 | Super-high wear-resistance hypereutectoid pearlite steel rail material added with rare earth and nickel elements |
| CN114058813A (en) * | 2021-11-23 | 2022-02-18 | 包头钢铁（集团）有限责任公司 | Control method of hypereutectoid rare earth steel rail network carbide |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN110592355B (en) | Production method for reducing residual stress of heat-treated steel rail and steel rail obtained by production method | |
| CN106319378B (en) | Steel for large-diameter thin saw blade matrix and manufacturing method thereof | |
| CN105483555B (en) | Spring steel and preparation method thereof and heat treatment method | |
| CN110527910B (en) | Preparation method of corrosion-resistant nano pearlite steel rail containing rare earth Ce and Nb elements | |
| CN115505713B (en) | Heat treatment process for reducing residual stress of hundred-meter online heat-treated bainitic steel rail | |
| CN112877531B (en) | Production control method for improving flatness of steel rail after online heat treatment quenching | |
| CN112689541B (en) | Method for manufacturing railway rails with improved wear resistance and contact strength | |
| CN113462985B (en) | Low-cost high-surface-hardness tool steel with excellent annealing-free bending performance | |
| CN118127287A (en) | Superfine lamellar spacing pearlite steel rail control cooling process | |
| CN110578041B (en) | Corrosion-resistant superfine pearlite material added with rare earth Ce and Nb elements | |
| CN115369229A (en) | Production control method for improving flatness of turnout steel rail after on-line heat treatment quenching | |
| CN106893950A (en) | Low yield strength ratio cold rolling weather resisting steel and its production method | |
| CN113549830B (en) | Medium carbon spheroidized sorbite tool steel with high surface hardness and excellent bending property and production method thereof | |
| CN113564469B (en) | High-carbon spheroidized sorbite cutting tool steel with high surface hardness and excellent bending property and production method thereof | |
| CN118326151A (en) | Control method for improving flatness of R350HT heat treated steel rail | |
| CN114959473A (en) | Steel for thrust wheel of bulldozer and production method thereof | |
| CN1410584A (en) | High performance soft steel magnet for magnetic suspension train | |
| CN117327985B (en) | B, ti microalloyed hot rolled bainite rail and manufacturing method thereof | |
| CN110885950A (en) | High-strength and high-toughness steel rail for crane and manufacturing method thereof | |
| CN109763072A (en) | A kind of think gauge high-wearing feature steel plate and its manufacturing method | |
| CN115318827B (en) | Rolling method of low-cost U71Mn steel rail | |
| CN118321388A (en) | Bainite steel rail straightening method with low additional residual stress through online heat treatment | |
| CN113549841B (en) | 1200MPa heat-treatment-free low-cost troostite tool steel and production method thereof | |
| CN117327985A (en) | B, ti microalloyed hot rolled bainite steel rail and manufacturing method thereof | |
| CN116814922A (en) | Method for reducing residual stress of rare earth heat treated steel rail |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| RJ01 | Rejection of invention patent application after publication |
Application publication date: 20221122 |