CN109182720A - A kind of heat treatment method of Produce Heavy Nodular lron collars - Google Patents

A kind of heat treatment method of Produce Heavy Nodular lron collars Download PDF

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Publication number
CN109182720A
CN109182720A CN201810930117.8A CN201810930117A CN109182720A CN 109182720 A CN109182720 A CN 109182720A CN 201810930117 A CN201810930117 A CN 201810930117A CN 109182720 A CN109182720 A CN 109182720A
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Prior art keywords
collars
heat treatment
heating rate
treatment method
temperature
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CN201810930117.8A
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Inventor
付家双
杨德明
李元成
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CHENGDU SANQIANG ZHAGUN Co Ltd
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CHENGDU SANQIANG ZHAGUN Co Ltd
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Priority to CN201810930117.8A priority Critical patent/CN109182720A/en
Publication of CN109182720A publication Critical patent/CN109182720A/en
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    • 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
    • C21D9/40—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for rings; for bearing races
    • 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
    • C21D1/78—Combined heat-treatments not provided for above
    • C21D1/785—Thermocycling
    • 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
    • C21D5/00—Heat treatments of cast-iron
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C22C37/04—Cast-iron alloys containing spheroidal graphite
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C22C37/06—Cast-iron alloys containing chromium
    • C22C37/08—Cast-iron alloys containing chromium with nickel
    • C—CHEMISTRY; METALLURGY
    • C22—METALLURGY; FERROUS OR NON-FERROUS ALLOYS; TREATMENT OF ALLOYS OR NON-FERROUS METALS
    • C22C—ALLOYS
    • C22C37/00—Cast-iron alloys
    • C22C37/10—Cast-iron alloys containing aluminium or silicon

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

Abstract

The present invention discloses a kind of heat treatment method of Produce Heavy Nodular lron collars, belongs to collars manufacturing technology field, including the improvement to normalizing and tempering process, collars chemical component are as follows: C:3.2-3.5%；Si:1.7-1.9%；Mn:0.7-0.8%；P:0-0.08%；S:0-0.015%；Cr:0.8-0.9%；Ni:1.5-2.0%；Mo:0.3-0.5%；Remaining is Fe；Pass through the improvement to normalizing and tempering process, and the adjustment of mating collars chemical composition, to solve the problems, such as the medium-and-large-sized collars cracking of heat treatment temperature-rise period, the manufacturing process for large-scale collars provides effective heat treatment method, reduces production risk and cost.

Description

A kind of heat treatment method of Produce Heavy Nodular lron collars
Technical field
The invention belongs to collars manufacturing technology fields, more particularly to a kind of Produce Heavy Nodular lron collars and its heat treatment method.
Background technique
Collars (roll collar) is the part belonged between section roll body of roll top pass or other than groove.For big The collars (such as Φ 2000 × 1800,25 tons of weight) of type, it is higher to the positive tempering heating requirements in heat treatment process, it is no Then during heating, as thermal stress and external force it is excessive caused by the heat treatment furnace the temperature rise period occur workpiece before phase change Cracking, bursts, causes to scrap, and increases company's manufacturing cost, and waste time.
Published patent of invention (publication number: CN104946874A) discloses and is greater than 1400mm, height for diameter 800mm or more, 2 tons of weight or more of large-scale collars carry out normalizing heat treatment method, and practical by practical proof, and this method exists When being equal to the large-scale collars of 2000 × 1800mm of Φ or so for diameter, it still can burst, not be able to satisfy the manufacturing It needs.
Summary of the invention
To solve the above-mentioned problems, the present invention provides a kind of Produce Heavy Nodular lron collars and its heat treatment method, for Large Roller Ring improves the technique being just tempered, and solves the problems, such as to burst in heat treatment process.For this purpose, the present invention uses Technical solution be:
A kind of heat treatment method of Produce Heavy Nodular lron collars is provided, as the important method in collars preparation process, the present invention Heat treatment method be directed to the large-scale collars having a size of 2000 × 1800mm of Φ comprising following steps:
(1) the heating rate for using 11-13 DEG C/h, is heated to 200 DEG C from room temperature for collars temperature, and with 200 DEG C of heat preservation 6- 8h；
(2) collars temperature is heated to 320 DEG C from 200 DEG C, and is kept the temperature with 320 DEG C by the heating rate for using 14-16 DEG C/h 18-20h；
(3) collars temperature is heated to 500 DEG C from 320 DEG C, and is kept the temperature with 500 DEG C by the heating rate for using 17-19 DEG C/h 5-7h；
(4) collars temperature is heated to 620 DEG C from 500 DEG C, and is kept the temperature with 620 DEG C by the heating rate for using 17-19 DEG C/h 16-18h；
(5) collars temperature is heated to 920 DEG C from 620 DEG C, and is kept the temperature with 920 DEG C by the heating rate for using 38-42 DEG C/h 9-11h；
(6) processing is blowed in collars, collars is made to be cooled to 500 DEG C in 1.5-2.5h, stop blowing；
(7), by after the cooling 1-2h of collars, the heating rate in furnace with 20 DEG C/h is hung in, is heated to 530 DEG C, and protect with 530 DEG C Warm 24-26h；
(8) collars furnace cooling is come out of the stove to 120 DEG C, heat treatment process finishes.
Further, the collars chemical component are as follows: C:3.2-3.5%；Si:1.7-1.9%；Mn:0.7-0.8%； P:0-0.08%；S:0-0.015%；Cr:0.8-0.9%；Ni:1.5-2.0%；Mo:0.3-0.5%；Remaining is Fe.
Further, the heating rate is 12 DEG C/h in the step (1), the room temperature is less than or equal to 40 DEG C, protects The warm time is 6h.
Further, the heating rate is 15 DEG C/h in the step (2), the time of heat preservation is 18h.
Further, the heating rate is 18 DEG C/h, soaking time 5h in the step (3).
Further, the heating rate is 18 DEG C/h, soaking time 16h in the step (4).
Further, the heating rate is 40 DEG C/h, soaking time 9h in the step (5).
Further, the time of heat preservation is for 24 hours in the step (7).
Using the technical program the utility model has the advantages that
For the Large Roller ring having a size of Φ 2000 × 1800mm rank, the improved heat treatment method of collars of the invention, And the adjustment to chemical composition, the collars inside and outside temperature difference is reduced, thermal stress is reduced, collars cracking factor reduces；Reinforce Support to collars, reduce collars because gravity there are due to the shearing force that generates, to efficiently solve heat treatment heating In the process the problem of Large Roller ring opening；
Mature heat treatment method is provided for the manufacturing process of large-scale collars, reduces production risk and cost.
Specific embodiment
To make the objectives, technical solutions, and advantages of the present invention clearer, combined with specific embodiments below to the present invention It is further elaborated.
Embodiment one:
In the present embodiment, a kind of heat treatment method of Produce Heavy Nodular lron collars is provided, comprising the following steps:
(1) collars temperature is heated to 200 DEG C from room temperature (15 DEG C), and is protected with 200 DEG C by the heating rate for using 12 DEG C/h Warm 6h；
(2) the heating rate for using 15 DEG C/h, is heated to 320 DEG C from 200 DEG C for collars temperature, and with 320 DEG C of heat preservation 18h；
(3) the heating rate for using 18 DEG C/h, is heated to 500 DEG C from 320 DEG C for collars temperature, and with 500 DEG C of heat preservation 5h；
(4) the heating rate for using 18 DEG C/h, is heated to 620 DEG C from 500 DEG C for collars temperature, and with 620 DEG C of heat preservation 16h；
(5) the heating rate for using 40 DEG C/h, is heated to 920 DEG C from 620 DEG C for collars temperature, and with 920 DEG C of heat preservation 9h；
(6) processing is blowed in collars, collars 2h is made to be cooled to 500 DEG C, stop blowing；
(7) the heating rate in furnace with 20 DEG C/h after the air-cooled 1h of collars, will be hung in, be heated to 530 DEG C, and keep the temperature with 530 DEG C 24h；
(8) collars furnace cooling is come out of the stove to 120 DEG C, heat treatment process finishes.
The size of the collars is 2000 × 1800mm of Φ, chemical component are as follows: C:3.2%；Si:1.9%；Mn: 0.7%；P:0.05%；S:0.015%；Cr:0.8%；Ni:2.0%；Mo:0.3%；Remaining is Fe.
Embodiment two:
In the present embodiment, a kind of heat treatment method of Produce Heavy Nodular lron collars is provided, comprising the following steps:
(1) collars temperature is heated to 200 DEG C from room temperature (30 DEG C), and is protected with 200 DEG C by the heating rate for using 13 DEG C/h Warm 8h；
(2) the heating rate for using 16 DEG C/h, is heated to 320 DEG C from 200 DEG C for collars temperature, and with 320 DEG C of heat preservation 20h；
(3) the heating rate for using 19 DEG C/h, is heated to 500 DEG C from 320 DEG C for collars temperature, and with 500 DEG C of heat preservation 7h；
(4) the heating rate for using 19 DEG C/h, is heated to 620 DEG C from 500 DEG C for collars temperature, and with 620 DEG C of heat preservation 18h；
(5) the heating rate for using 42 DEG C/h, is heated to 920 DEG C from 620 DEG C for collars temperature, and with 920 DEG C of heat preservation 11h；
(6) processing is blowed in collars, collars 2.5h is made to be cooled to 500 DEG C, stop blowing；
(7) the heating rate in furnace with 20 DEG C/h after the air-cooled 2h of collars, will be hung in, be heated to 530 DEG C, and keep the temperature with 530 DEG C 26h；
(8) collars furnace cooling is come out of the stove to 120 DEG C, heat treatment process finishes.
The diameter of the collars is equal to 2000 × 1800mm of Φ, chemical component are as follows: C:3.5%；Si:1.7%；Mn: 0.8%；P:0.08%；S:0.015%；Cr:0.9%；Ni:1.5%；Mo:0.5%；Remaining is Fe.
Embodiment three:
In the present embodiment, a kind of heat treatment method of Produce Heavy Nodular lron collars is provided, comprising the following steps:
(1) collars temperature is heated to 200 DEG C from room temperature (25 DEG C), and is protected with 200 DEG C by the heating rate for using 11 DEG C/h Warm 7h；
(2) the heating rate for using 14 DEG C/h, is heated to 320 DEG C from 200 DEG C for collars temperature, and with 320 DEG C of heat preservation 20h；
(3) the heating rate for using 17 DEG C/h, is heated to 500 DEG C from 320 DEG C for collars temperature, and with 500 DEG C of heat preservation 7h；
(4) the heating rate for using 17 DEG C/h, is heated to 620 DEG C from 500 DEG C for collars temperature, and with 620 DEG C of heat preservation 18h；
(5) the heating rate for using 38 DEG C/h, is heated to 920 DEG C from 620 DEG C for collars temperature, and with 920 DEG C of heat preservation 11h；
(6) processing is blowed in collars, collars 1.5h is made to be cooled to 500 DEG C, stop blowing；
(7) the heating rate in furnace with 20 DEG C/h after the air-cooled 2h of collars, will be hung in, be heated to 530 DEG C, and keep the temperature with 530 DEG C 26h；
(8) collars furnace cooling is come out of the stove to 120 DEG C, heat treatment process finishes.
The size of the collars is 2000 × 1800mm of Φ, chemical component are as follows: C:3.3%；Si:1.8%；Mn: 0.8%；P:0.06%；S:0.015%；Cr:0.9%；Ni:1.8%；Mo:0.4%；Remaining is Fe.
Comparative examples:
In the present embodiment, a kind of heat treatment method of Produce Heavy Nodular lron collars is provided, comprising the following steps:
(1) the heating rate of 15 DEG C/h is used, collars temperature is heated to 200 DEG C from room temperature (25 DEG C), and protect with 200 DEG C Warm 5h；
(2) the heating rate for using 15 DEG C/h, is heated to 320 DEG C from 200 DEG C for collars temperature, and with 320 DEG C of heat preservation 12h；
(3) the heating rate for using 18 DEG C/h, is heated to 500 DEG C from 320 DEG C for collars temperature, and with 500 DEG C of heat preservation 5h；
(4) the heating rate for using 18 DEG C/h, is heated to 620 DEG C from 500 DEG C for collars temperature, and with 620 DEG C of heat preservation 16h；
(5) processing is blowed in collars, collars 1.0h is made to be cooled to 500 DEG C, stop blowing；
(6) the heating rate in furnace with 20 DEG C/h after the air-cooled 2h of collars, will be hung in, be heated to 530 DEG C, and keep the temperature with 530 DEG C 26h；
(7) collars furnace cooling is come out of the stove to 120 DEG C, heat treatment process finishes.
The collars is having a size of Φ 2000 × 1800, chemical component are as follows: C:3.3%；Si:1.8%；Mn:0.8%；P: 0.06%；S:0.015%；Cr:0.9%；Ni:1.8%；Mo:0.4%；Remaining is Fe.
The specific data of the large-scale collars of above-described embodiment such as table 1:
Table 1:
As can be seen that being directed to the large-scale collars having a size of 2000 × 1800mm of Φ in table 1, heat treatment side of the invention is used When method produces, hardness is moderate, and core carbide is less than 10%, and production 100 or more is not sent to burst；And according to control When people's processing method of embodiment produces the large-scale collars having a size of 2000 × 1800mm of Φ, excessive high hardness, core carbide surpasses Mark, causes internal-external temperature difference excessive, bursts.
The basic principles, main features and advantages of the present invention have been shown and described above.The technology of the industry Personnel are it should be appreciated that the present invention is not limited to the above embodiments, and the above embodiments and description only describe this The principle of invention, without departing from the spirit and scope of the present invention, various changes and improvements may be made to the invention, these changes Change and improvement all fall within the protetion scope of the claimed invention.The claimed scope of the invention by appended claims and its Equivalent thereof.

Claims (9)

1. a kind of heat treatment method of Produce Heavy Nodular lron collars, comprising the following steps:
(1) the heating rate for using 11-13 DEG C/h, is heated to 200 DEG C from room temperature for collars temperature, and with 200 DEG C of heat preservation 6-8h；
(2) the heating rate for using 14-16 DEG C/h, is heated to 320 DEG C from 200 DEG C for collars temperature, and with 320 DEG C of heat preservation 18- 20h；
(3) the heating rate for using 17-19 DEG C/h, is heated to 500 DEG C from 320 DEG C for collars temperature, and with 500 DEG C of heat preservation 5-7h；
(4) the heating rate for using 17-19 DEG C/h, is heated to 620 DEG C from 500 DEG C for collars temperature, and with 620 DEG C of heat preservation 16- 18h；
(5) the heating rate for using 38-42 DEG C/h, is heated to 920 DEG C from 620 DEG C for collars temperature, and with 920 DEG C of heat preservation 9- 11h；
(6) processing is blowed in collars, collars is made to be cooled to 500 DEG C in 1.5-2.5h, stop blowing；
(7), by after the cooling 1-2h of collars, the heating rate in furnace with 20 DEG C/h is hung in, is heated to 530 DEG C, and keep the temperature with 530 DEG C 24-26h；
(8) collars furnace cooling is come out of the stove to 120 DEG C, heat treatment process finishes.
2. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the collars chemistry Ingredient are as follows: C:3.2-3.5%；Si:1.7-1.9%；Mn:0.7-0.8%；P:0-0.08%；S:0-0.015%；Cr:0.8- 0.9%；Ni:1.5-2.0%；Mo:0.3-0.5%；Remaining is Fe.
3. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the step (1) In, the heating rate is 12 DEG C/h, and the room temperature is less than or equal to 40 DEG C, soaking time 6h.
4. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the step (2) In, the heating rate is 15 DEG C/h, and the time of heat preservation is 18h.
5. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the step (3) In, the heating rate is 18 DEG C/h, soaking time 5h.
6. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the step (4) In, the heating rate is 18 DEG C/h, soaking time 16h.
7. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the step (5) In, the heating rate is 40 DEG C/h, soaking time 9h.
8. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1, it is characterised in that: the step (7) In, the time of heat preservation is for 24 hours.
9. a kind of heat treatment method of Produce Heavy Nodular lron collars according to claim 1 or 2, it is characterised in that: the collars Size be 2000 × 1800mm of Φ.
CN201810930117.8A 2018-08-15 2018-08-15 A kind of heat treatment method of Produce Heavy Nodular lron collars Pending CN109182720A (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102618779A (en) * 2012-02-24 2012-08-01 常州宝菱重工机械有限公司 As-cast bainite ductile cast iron composite roll
CN104946874A (en) * 2015-07-24 2015-09-30 成都三强轧辊股份有限公司 Large-size roll collar normalizing heating method
CN105316565A (en) * 2015-11-26 2016-02-10 常州凯达重工科技有限公司 High-strength low-hardness ferritic nodular cast iron roller ring and manufacturing method thereof
CN105401056A (en) * 2015-10-28 2016-03-16 中钢集团邢台机械轧辊有限公司 Universal type steel ball unthreaded ball iron roller ring and manufacturing method thereof
CN106917035A (en) * 2017-01-20 2017-07-04 中钢集团邢台机械轧辊有限公司 A kind of wear-resisting type ferrochrome collars high and its manufacture method

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102618779A (en) * 2012-02-24 2012-08-01 常州宝菱重工机械有限公司 As-cast bainite ductile cast iron composite roll
CN104946874A (en) * 2015-07-24 2015-09-30 成都三强轧辊股份有限公司 Large-size roll collar normalizing heating method
CN105401056A (en) * 2015-10-28 2016-03-16 中钢集团邢台机械轧辊有限公司 Universal type steel ball unthreaded ball iron roller ring and manufacturing method thereof
CN105316565A (en) * 2015-11-26 2016-02-10 常州凯达重工科技有限公司 High-strength low-hardness ferritic nodular cast iron roller ring and manufacturing method thereof
CN106917035A (en) * 2017-01-20 2017-07-04 中钢集团邢台机械轧辊有限公司 A kind of wear-resisting type ferrochrome collars high and its manufacture method

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