CN1034583A - Produce the heat treating method and the device of high duty rails - Google Patents
Produce the heat treating method and the device of high duty rails Download PDFInfo
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- CN1034583A CN1034583A CN 88105864 CN88105864A CN1034583A CN 1034583 A CN1034583 A CN 1034583A CN 88105864 CN88105864 CN 88105864 CN 88105864 A CN88105864 A CN 88105864A CN 1034583 A CN1034583 A CN 1034583A
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Abstract
The heat treating method of producing high duty rails the steps include:
The rail of a roll forming is carried out preheating, heating, air cooling, the pressurized air cooling, fog cooling and controlled deformation are handled.Thereby in the dark scope of rail's end portion, obtain the nodular troostite tissue of high rigidity, and hardness descends evenly inwards from the rail's end portion surface.Reduced its arching along length.The both sides shower nozzle of three-dimensional air-jet device has certain angle, has improved the homogeneity that rail's end portion is strengthened well.
Description
The invention belongs to heat treatment technics.
Along with the increase day by day of road speed, axle weight and goods, volume of passenger traffic, cause the rapid wearing and the fatigue of rail's end portion in the transportation by railroad, cause rail significantly to reduce work-ing life.In order to improve the use properties of rail, both at home and abroad the full length rail quenching method is developed, to produce rail, satisfy the needs of transportation by railroad with high-wearing feature and high-fatigue strength.
As the clear 55-23885 of the Japanese Patent of prior art, described the heat treating method that a kind of production has certain intensity rail in detail.Yet, adopt the method for this patent introduction but to have tangible deficiency:
1. the rail head of rail intensity after Overheating Treatment is inhomogeneous;
2. the arching along its length of the rail after Overheating Treatment is big;
3. the whole production linear velocity is slow, influences the raising of output.
4. air consumption height.
The objective of the invention is, a kind of heat treating method of producing high duty rails is provided, can not only to the dark scope of lining, obtain the nodular troostite tissue that hardness evenly descends by table at rail's end portion, and can also make rail obtain less deflection along its length, can also improve throughput simultaneously.
Another object of the present invention is to provide a kind of thermal treatment unit of producing high duty rails, with the further homogeneity of improving the distribution of rail's end portion surface hardness.
A kind of heat treating method of producing high duty rails provided by the present invention the steps include:
Use the power frequency induction installation to its whole preheating the rail of a roll forming, preferably make rail be preheating to 500～550 ℃ with the preheating speed of 2.0～5.0 ℃/S.
With the Medium frequency induction device rail's end portion being heated, preferably make rail's end portion be heated to the above temperature province in austenitic area with the rate of heating of 6.5～20.0 ℃/S, exactly is at 850～950 ℃;
Then, air cooling is to the certain temperature zone under the physical environment temperature to make rail, and air cooling to 780～730 ℃ preferably are with the temperature in the even rail head of rail.
Then,, pressurized air is sprayed to rail's end portion, it is heat-treated with being configured in rail's end portion three-dimensional air-jet device on every side.Three-dimensional air-jet device is made up of the shower nozzle of a cooling rail's end portion tread and the shower nozzle of a pair of cooling rail's end portion two sides, and the dozens of nozzle is arranged on each shower nozzle, and both sides shower nozzle and rail section symmetry axis constitute 1～10 ° angle.Three-dimensional air-jet device is with 40～70m
3The flow of/min sprays to rail's end portion with pressurized air, makes its speed of cooling with 4.6～15 ℃/S be cooled to 550～450 ℃.
And then, with the three-dimensional nozzle unit that is configured in around the rail's end portion, with predetermined flow with spray painting to its head, make it be cooled to certain temperature province with certain speed of cooling, rail's end portion is deepened to handle.Preferably make three-dimensional nozzle unit with the discharge of 150～250l/Hr with spray painting to rail's end portion, make its speed of cooling be cooled to 450～200 ℃ with 4.4～11.1 ℃/S, with guarantee the rail's end portion surface inwards the speed of cooling to 15～25mm scope be within the velocity of transformation scope of nodular troostite.Thereby obtain the nodular troostite tissue that hardness evenly descends, its Vickers' hardness is that 400 to 306(Brinell hardness are 390 to 300).
At last, liquid cooling medium is sprayed to rail's end portion, make the certain temperature difference of maintenance between the rail head and the flange of rail, with along its length the deflection after heat treatment of control rail with other refrigerating unit.Preferably make the rail head temperature be higher than flange of rail temperature between 50～100 ℃.
In whole heat treatment process, rail is with respect to the unidirectional movement continuously of thermal treatment unit, and its speed can be brought up to 0.8～1.6m/min.
In order to obtain to have different high-intensity rail, can realize that its Hv can determine by following formula by the speed of cooling that different compressed air requires is adjusted quenching:
Hv=9V+265 V-speed of cooling
Fig. 1 is the example side-view of the said method of the present invention;
Fig. 2 is for implementing the cooling curve of rail's end portion speed of cooling when of the present invention;
Fig. 3 is each several part title synoptic diagram in the surf zone in explanation rail's end portion cross section;
Fig. 4 is the said three-dimensional air-jet device side-view of the present invention;
Fig. 5 is for adopting the rail buckle result of the said method of the present invention;
Fig. 6 a and 6b are respectively hardness measurement result and curve thereof on the cross section after the 50kg/m rail is heat-treated;
Fig. 7 a and 7b are respectively hardness measurement result and curve thereof on the cross section after the 60kg/m rail is heat-treated;
Fig. 8 a and 8b are respectively hardness measurement result and curve thereof on the cross section after the 75kg/m rail is heat-treated;
Hardness measurement result and curve on the cross section after the 50kg/m rail that Fig. 9 a and 9b are respectively secondary intensity is heat-treated.
Below, give an example in conjunction with the accompanying drawings with regard to main points of the present invention, explained.
Fig. 1 is embodiments of the invention.Feed rolls 1 is sent into the continuous uniaxially of rail in the thermal treatment unit with the speed of 0.8～1.6m/min and is heat-treated.Primary heater unit 2 is general line-frequency induction device, and it covers on the rail entirely, utilizes the induced current produced that rail integral body is preheating to 500～550 ℃ with the preheating speed of 2.0～5.0 ℃/S.Heating unit 3 is general intermediate frequency inductor, and it only covers on rail's end portion, its utilize produced induced current rail's end portion is heated to 850～950 ℃ with the rate of heating of 6.5～20.0 ℃/S.By preheating and heating, make rail's end portion have very little thermograde, and the heat that contains is many, the flange of rail temperature of control rail deflection along its length is provided again simultaneously.Thermoscope 4 is positioned at the exit of heating unit 3, to detect the Heating temperature of rail.Then, make rail proper temperature between air cooling to 780～730 under the physical environment temperature ℃, further to reduce the thermograde of rail's end portion.Three-dimensional air-jet device 5 is made up of the shower nozzle 12 of a cooling rail's end portion tread and the shower nozzle 13 of a pair of cooling rail's end portion two sides, and they are connected to the control valve of compressed air source respectively, and shower nozzle 12 and shower nozzle 13 are gas circuit independently.Dozens of nozzle 14 is arranged on each shower nozzle.Both sides shower nozzle and rail cut the section symmetry axis and constitute 1～10 ° angle theta, be characterized in, the pressurized air stream that sprays to rail's end portion flowed to more be tending towards rationally having improved the homogeneity of hardness, the hardness of angle, garden and tread is reached unanimity, increased the cooling performance of Xia Yuan angle and lower jaw simultaneously.Three-dimensional air-jet device 5 is with 40～70m
3The flow of/min sprays to rail's end portion with pressurized air, makes its speed of cooling with 4.6～15 ℃/S be cooled to 550～450 ℃, can guarantee to obtain on the rail's end portion surface the uniform nodular troostite tissue of temperature.Three-dimensional nozzle unit 6 is made up of the shower nozzle of a cooling rail's end portion tread and the shower nozzle of a pair of cooling rail's end portion two sides.Each shower nozzle all has independently (the both sides shower nozzle also can be a system) gas, water route.The dozens of nozzle is arranged on each shower nozzle.Control three-dimensional nozzle unit 6 with the discharge of 150～250l/Hr with spray painting to rail's end portion, make its speed of cooling be cooled to 450～200 ℃ with 4.4～11.1 ℃/S, to guarantee obtaining the nodular troostite tissue that hardness evenly descends inwards to 15～25mm scope on the rail's end portion surface, its Vickers' hardness is 400 to 306.Adjust roller 7 in order to adjust the position of rail.A pair of temperature gauge head 8, be installed in rail's end portion and rail foot respectively, to measure the temperature difference of rail's end portion and bottom, send it to controller then, with controlled chilling device 9 an amount of liquid cooling medium (for example water, cooling fluid, wet goods) is sprayed to rail's end portion, make rail's end portion be higher than bottom temp and remain on the temperature range of regulation, promptly 50～100 ℃, can make rail along its length deflection after thermal treatment be reduced to h＜100mm/25m.In addition, the primary heater unit 2 among Fig. 1, heating unit 3, thermoscope 4, three-dimensional air-jet device 5, three-dimensional nozzle unit 6, temperature gauge head 8 and refrigerating unit 9 are ordered arrangement and are fixed on the support, and be irrelevant with transmission system.Rail 10 is to move from left to right.Fig. 2 is 1. 6mm under the tread of presentation graphs 1 heat-treated rail head, 2. goes up 6mm under the angle, garden, 3. goes up the cooling curve at 18mm place under the angle, garden.
Example 1 usefulness chemical ingredients is (weight %): 0.78% carbon, 0.23% silicon, 0.85% manganese ,≤0.35% sulphur, phosphorus, all the other are heat-treated with this invention under the speed of 1.30m/min for the 50kg/m rail of iron and trace element, other conditions are: 4.8 ℃/S of preheating speed, 540 ℃ of preheating temperatures, 18 ℃/S of rate of heating, 890 ℃ of Heating temperatures, air cooling to 760 ℃, the angle theta of the both sides shower nozzle 13 of three-dimensional air-jet device are 8 degree.With flow is 40m
3The compressed air spraying rail's end portion of/min makes its speed of cooling with 11 ℃/S be cooled to 500 ℃, is that the spray painting of 160l/Hr blows rail's end portion with discharge, makes its speed of cooling with 8.3 ℃/S be cooled to 200 ℃; Be sprayed at rail's end portion with an amount of liquid cooling medium water by refrigerating unit, make rail's end portion higher 50 ℃ than the bottom.Hardness measurement result on the resulting rail head of rail cross section and curve are shown in Fig. 6 a and 6b, and its mechanical property is:
On the 25m rail, arch along its length is curved to be 40mm.
Example 2 usefulness chemical ingredientss are (weight %): 0.77% carbon, and 0.25% silicon, 0.88% manganese ,≤0.035% sulphur, phosphorus, all the other are iron and other micro-60kg/m rail, heat-treat with this invention under the speed of 1.21m/min.Other conditions are: 4.1 ℃/S of preheating speed, and preheating temperature is 545 ℃; 14 ℃/S of rate of heating, 930 ℃ of Heating temperatures; Air cooling to 778 ℃; The angle theta of the both sides shower nozzle 13 of three-dimensional air-jet device is 6 degree.With flow is 55m
3The compressed air spraying rail's end portion of/min makes its speed of cooling with 10.5 ℃/S be cooled to 490 ℃; With discharge is that the spray painting of 220l/Hr blows rail's end portion, makes its speed of cooling with 9.1 ℃/S be cooled to 250 ℃; Be sprayed at rail's end portion with an amount of water, make rail's end portion higher 70 ℃ than the bottom; Hardness measurement result on the resulting rail head of rail cross section and curve shown in Fig. 7 a and 7b, its mechanical property:
On the 25m rail, arch along its length is curved to be 90mm.
Example 4 usefulness chemical ingredientss are (weight %): 0.78% carbon, and 0.27% silicon, 0.95% manganese ,≤0.035% sulphur, phosphorus, all the other are the 75kg/m rail of iron and other impurity, adopt the present invention to heat-treat under the speed of 1.20m/min.Other conditions are: 4.5 ℃/S of preheating speed, 550 ℃ of preheating temperatures; 12 ℃/S of rate of heating, 910 ℃ of Heating temperatures; Air cooling to 770 ℃; The angle theta of the both sides shower nozzle of three-dimensional air-jet device is 5 degree.With flow is 70m
3The compressed air spraying rail's end portion of/min.Making its speed of cooling with 10 ℃/S be cooled to 480 ℃, is that the spray painting of 220l/Hr blows rail's end portion with discharge again, makes its speed of cooling with 9.8 ℃/S be cooled to 280 ℃; Spray rail's end portion with an amount of water, make rail's end portion higher 80 ℃ than the bottom, hardness measurement result on the resulting rail head of rail cross section and curve shown in Fig. 8 a and 8b, its mechanical property:
On the 25m rail, deflection along its length is 80mm.
Example 4 adopts the steel grade composition identical with example 1, Hv=9V+265 as can be known, only need to change the compressed-air actuated speed of cooling in other conditions, then can obtain the rail of secondary intensity, be set in the rail's end portion tread and obtain the pearlitic structure that intensity evenly descends in the 20mm inwards, its Vickers' hardness is 340 to 304, and then can obtain V is 7.5 ℃/S, hardness measurement result on the resulting rail head of rail cross section and curve are shown in Fig. 9 a and 9b, and its mechanical property is:
On the 25m rail, deflection along its length is 45mm.
Following table is the heat-treated rail of employing the present invention production and the actual laying of the heat-treated steel gauge lines Experimental Comparison result of Nippon Steel Manufacturing Corp.
Annotate: 1. this table is the test result of upper track after 1 year;
2. the annual traffic that is passed through is 7,200 ten thousand tons.
Claims (6)
1, a kind of heat treating method of producing high duty rails the steps include:
The rail of a roll forming is carried out preheating with the power frequency induction installation to its integral body;
With the Medium frequency induction device its head is heated to the above temperature province in austenitic area again;
Make its air cooling under the physical environment temperature arrive certain temperature province;
With being configured in its head three-dimensional air-jet device on every side, with predetermined flow pressurized air is sprayed to its head, make it be cooled to certain temperature province with certain speed of cooling;
The present invention is characterized in that:
Also disposed three-dimensional nozzle unit around its head, with predetermined flow with spray painting to its head, make it be cooled to certain temperature province with certain speed of cooling;
Also the refrigerating unit with other sprays to rail's end portion with liquid cooling medium, makes the certain temperature difference of maintenance between the rail head and the flange of rail, and its scope is that rail head is higher than 50～100 ℃ of the flanges of rail;
2, as the said method of claim 1, it is characterized in that:
Rail is preheating to 500～550 ℃ with the preheating speed of 2.0～5.0 ℃/S;
Rail's end portion is heated to 850～950 ℃ with the rate of heating of 6.5～20.0 ℃/S;
Air cooling to 780 under the physical environment temperature～730 ℃;
With pressurized air with 40～70m
3The flow of/min makes its speed of cooling with 4.6～15 ℃/S be cooled to 550～450 ℃ to rail head of rail portion;
Spray to rail's end portion with mist with the discharge of 150～250l/Hr, make its speed of cooling be cooled to 450～200 ℃ with 4.4-11.1 ℃/S;
3, as the said method of claim 2, it is characterized in that:
In whole heat treatment process, rail is with respect to the unidirectional movement continuously of thermal treatment unit, and its speed is 0.8～1.6m/min;
4, as the said method of claim 2, it is characterized in that:
Can obtain the nodular troostite tissue that hardness evenly descends inwards to 15～25mm scope at the rail's end portion tread, its Vickers' hardness is 400 to 306;
5, as the said method of claim 4, it is characterized in that:
The speed of cooling of rail's end portion is produced the rail with varying strength in the time of can adjusting quenching by different compressed air requires, and its Hv can determine by following formula:
Hv=9V+265 V-speed of cooling
6, a kind of thermal treatment unit of producing high duty rails, comprise three-dimensional air-jet device, it is made up of the shower nozzle of a cooling rail's end portion tread and the shower nozzle of a pair of cooling rail's end portion two sides, the present invention is characterized in that: the dozens of nozzle is arranged on each shower nozzle, and both sides shower nozzle and rail profile symmetry axis constitute 1～10 ° angle.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 88105864 CN1012966B (en) | 1988-01-26 | 1988-01-26 | Heat treatment and its device for producing high strength steel rail |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN 88105864 CN1012966B (en) | 1988-01-26 | 1988-01-26 | Heat treatment and its device for producing high strength steel rail |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1034583A true CN1034583A (en) | 1989-08-09 |
| CN1012966B CN1012966B (en) | 1991-06-26 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN 88105864 Expired CN1012966B (en) | 1988-01-26 | 1988-01-26 | Heat treatment and its device for producing high strength steel rail |
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Cited By (12)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1044618C (en) * | 1995-01-25 | 1999-08-11 | 包头钢铁公司 | Steel rail in-line exhaust-heat strengthening process and its apparatus |
| CN100443617C (en) * | 2005-12-29 | 2008-12-17 | 攀枝花钢铁(集团)公司 | Pealite like thermal treating steel rail and producing method thereof |
| CN102086620A (en) * | 2010-03-19 | 2011-06-08 | 呼和浩特铁路局焊轨段 | Double-frequency process for normalizing rail welding seams |
| CN102086619A (en) * | 2010-03-19 | 2011-06-08 | 呼和浩特铁路局焊轨段 | Double-frequency equipment and process for normalizing rail welding seams |
| CN102836830A (en) * | 2012-08-31 | 2012-12-26 | 山东永聚医药科技有限公司 | Online detection and selection system for combined cover of plastic infusion container |
| CN103131826A (en) * | 2013-02-26 | 2013-06-05 | 内蒙古包钢钢联股份有限公司 | Steel rail on-line wind-jet quenching heat treatment simulation experiment device |
| CN104060075A (en) * | 2014-07-14 | 2014-09-24 | 攀钢集团攀枝花钢铁研究院有限公司 | Heat treatment method of improving depth of hardened layer of steel rail |
| CN107164625A (en) * | 2017-04-21 | 2017-09-15 | 中车齐齐哈尔车辆有限公司 | Brake beam preparation method |
| 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 |
| CN110777245A (en) * | 2019-11-05 | 2020-02-11 | 中国铁建重工集团股份有限公司道岔分公司 | Rod heating method, heating device and computer readable storage medium |
| CN112276030A (en) * | 2020-10-13 | 2021-01-29 | 攀钢集团攀枝花钢铁研究院有限公司 | High-strength delayed fracture-resistant hot-rolled steel rail and preparation method thereof |
-
1988
- 1988-01-26 CN CN 88105864 patent/CN1012966B/en not_active Expired
Cited By (20)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1044618C (en) * | 1995-01-25 | 1999-08-11 | 包头钢铁公司 | Steel rail in-line exhaust-heat strengthening process and its apparatus |
| CN100443617C (en) * | 2005-12-29 | 2008-12-17 | 攀枝花钢铁(集团)公司 | Pealite like thermal treating steel rail and producing method thereof |
| CN102086620A (en) * | 2010-03-19 | 2011-06-08 | 呼和浩特铁路局焊轨段 | Double-frequency process for normalizing rail welding seams |
| CN102086619A (en) * | 2010-03-19 | 2011-06-08 | 呼和浩特铁路局焊轨段 | Double-frequency equipment and process for normalizing rail welding seams |
| CN102086620B (en) * | 2010-03-19 | 2013-01-16 | 呼和浩特铁路局焊轨段 | Double-frequency process for normalizing rail welding seams |
| CN102086619B (en) * | 2010-03-19 | 2013-05-01 | 呼和浩特铁路局焊轨段 | Double-frequency equipment and process for normalizing rail welding seams |
| CN102836830A (en) * | 2012-08-31 | 2012-12-26 | 山东永聚医药科技有限公司 | Online detection and selection system for combined cover of plastic infusion container |
| CN103131826A (en) * | 2013-02-26 | 2013-06-05 | 内蒙古包钢钢联股份有限公司 | Steel rail on-line wind-jet quenching heat treatment simulation experiment device |
| CN104060075A (en) * | 2014-07-14 | 2014-09-24 | 攀钢集团攀枝花钢铁研究院有限公司 | Heat treatment method of improving depth of hardened layer of steel rail |
| CN104060075B (en) * | 2014-07-14 | 2016-05-04 | 攀钢集团攀枝花钢铁研究院有限公司 | Improve the heat treatment method of rail hardening layer depth |
| CN107164625A (en) * | 2017-04-21 | 2017-09-15 | 中车齐齐哈尔车辆有限公司 | Brake beam preparation method |
| CN107164625B (en) * | 2017-04-21 | 2019-09-10 | 中车齐齐哈尔车辆有限公司 | Brake beam preparation method |
| 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 |
| WO2020057538A1 (en) * | 2018-09-19 | 2020-03-26 | 武汉钢铁有限公司 | Steel rail inline heat treatment flatness control method |
| 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 |
| CN110358904B (en) * | 2019-05-30 | 2020-11-03 | 邯郸钢铁集团有限责任公司 | Method for controlling rail shape after on-line heat treatment of steel rail |
| CN110777245A (en) * | 2019-11-05 | 2020-02-11 | 中国铁建重工集团股份有限公司道岔分公司 | Rod heating method, heating device and computer readable storage medium |
| CN110777245B (en) * | 2019-11-05 | 2021-08-20 | 中国铁建重工集团股份有限公司道岔分公司 | Rod heating method, heating device and computer readable storage medium |
| CN112276030A (en) * | 2020-10-13 | 2021-01-29 | 攀钢集团攀枝花钢铁研究院有限公司 | High-strength delayed fracture-resistant hot-rolled steel rail and preparation method thereof |
| CN112276030B (en) * | 2020-10-13 | 2021-11-19 | 攀钢集团攀枝花钢铁研究院有限公司 | High-strength delayed fracture-resistant hot-rolled steel rail and preparation method thereof |
Also Published As
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|---|---|
| CN1012966B (en) | 1991-06-26 |
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