CN107254568A - The offline production method of high-carbon steel wire rod - Google Patents
The offline production method of high-carbon steel wire rod Download PDFInfo
- Publication number
- CN107254568A CN107254568A CN201710371157.9A CN201710371157A CN107254568A CN 107254568 A CN107254568 A CN 107254568A CN 201710371157 A CN201710371157 A CN 201710371157A CN 107254568 A CN107254568 A CN 107254568A
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- CN
- China
- Prior art keywords
- wire rod
- production method
- hardening
- carried out
- isothermal
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- 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.)
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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
- C21D1/19—Hardening; Quenching with or without subsequent tempering by interrupted quenching
- C21D1/20—Isothermal quenching, e.g. bainitic hardening
-
- 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
- C21D1/74—Methods of treatment in inert gas, controlled atmosphere, vacuum or pulverulent material
-
- 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
- C21D6/00—Heat treatment of ferrous alloys
-
- 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
- C21D9/52—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length
- C21D9/525—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for wires; for strips ; for rods of unlimited length for wire, for rods
-
- 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
- C21D2211/00—Microstructure comprising significant phases
Abstract
A kind of offline production method of high-carbon steel wire rod, including：Protective atmosphere heating is carried out to wire rod；Isothermal hardening is carried out to the wire rod after heating using salt bath；And to the wire rod take-up after isothermal hardening.
Description
Technical field
The invention belongs to material heat treatment technical field, more particularly to a kind of manufacture method of high-quality high-carbon steel wire rod.
Background technology
High-carbon steel material hot rolling disk is widely used, and demand is big, can be used for the fields such as bridge, tire, elevator, and manufacture is high
The gren rod of carbon steel material is generally rubbed air-cooled technique using traditional Stevr, and the temperature range of structural transformation is very big, it is impossible to
The local organization for avoiding wire rod focus from causing is thick, so as to cause the reduction of poker, it is impossible to meet the processing of deep processing industry
It is required that.
The content of the invention
In view of above-mentioned technical problem, in order to overcome the above-mentioned deficiencies of the prior art, the present invention propose a kind of high-carbon steel disk
The manufacture method of bar.
According to an aspect of the invention, there is provided a kind of offline production method of high-carbon steel wire rod includes：Wire rod is entered
Row protective atmosphere is heated；Isothermal hardening is carried out to the wire rod after heating using salt bath；And to after isothermal hardening
Wire rod take-up.
Alternatively, wire rod is carried out also including before protective atmosphere heating：Unwrapping wire is carried out to initial steel wire rod；And it is right
The wire rod that unwrapping wire is obtained carries out mechanical Shot Blasting.
Alternatively, isothermal hardening is carried out to the wire rod after heating with being received to the wire rod after isothermal hardening using salt bath
Also include between line：Surface clean is carried out to the wire rod after isothermal hardening.
Alternatively, during the progress protective atmosphere heating to wire rod, wire rod is warming up to 950-1050 DEG C, and in above-mentioned temperature
Degree is kept for about 2 minutes.
Alternatively, the hardening media of the salt bath is potassium nitrate, sodium nitrate.
Alternatively, the hardening media includes the potassium nitrate and 45% sodium nitrate that percentage by weight is 55%.
Alternatively, the austempering temperature is 450-550 DEG C, and isothermal quenching time is 3-5min.
Alternatively, water is added during the isothermal hardening in hardening media, the aqueous phase is for water and hardening media gross weight
Percentage by weight be 0.1%-0.68%.
Alternatively, the isothermal hardening is sorbitizing processing.
Alternatively, the cleaning uses 27-50 DEG C of water, and the temperature of the wire rod after over cleaning is maintained at 350-450 DEG C.
It can be seen from the above technical proposal that the present invention one of at least has the advantages that：
(1) wire rod of high-quality can be obtained by carrying out protective atmosphere heating and salt bath austempering to the steel wire rod after uncoiling,
The need for meeting deep processing industry；
(2) effect of mechanical descaling is optimized using mechanical Shot Blasting；
(3) control heat time and isothermal quenching time, and by adjusting furnace temp and quenching tank temperature control disk
The crystalline form and quenching structure of bar austenite, control cooling special by adjusting the water content in quenching tank in hardening media
Property.
Brief description of the drawings
Fig. 1 is the flow chart of the offline production method of one embodiment of the invention Carbon Steel Wire Rod；
Fig. 2 is the time-temperature figure of the offline production of one embodiment of the invention high-carbon steel wire rod.
Embodiment
Certain embodiments of the invention will be done with reference to appended accompanying drawing in rear and more comprehensively describe to property, some of but not complete
The embodiment in portion will be illustrated.In fact, various embodiments of the present invention can be realized in many different forms, and it should not be construed
To be limited to this several illustrated embodiment；Relatively the present invention is caused to meet applicable legal requirement there is provided these embodiments.
For the object, technical solutions and advantages of the present invention are more clearly understood, below in conjunction with specific embodiment, and reference
Accompanying drawing, the present invention is described in more detail.
The present invention is carried out uncoiling, de-scaling by the original wire rod produced to Gao Xian factories, added using the method for heat-treated offline
After heat, isothermal hardening is carried out in high temperature salt bath, by adjusting unwrapping wire speed, control heat time and isothermal quenching time,
By adjusting the crystalline form and quenching structure of furnace temp and quenching tank temperature control wire rod austenite, quenched by regulation
Water content in fiery groove in hardening media controls cooling characteristics, and finally through over cleaning and take-up, wire rod harvest is wrapped, full
The processing request of sufficient deep processing industry.
The embodiment of the present invention provides a kind of offline production method of high-carbon steel wire rod, following steps is specifically included, such as Fig. 1 institutes
Show：
S101 carries out unwrapping wire to initial steel wire rod；
The specification of initial steel wire rod is in 5.5-16mm, and manageable wire rod specification and steel grade are as shown in table 1.
Table 1
| Steel grade | Cord | Spring steel wire rod | Prestressed wire rod | Steel wire rope wire rod |
| Specification | 5.5mm | 5.5-16mm | 8-16mm | 6.5-10mm |
Initial steel wire rod unwrapping wire uses vertical drawoff structure, and the speed control of unwrapping wire is in 3-5m/min, pay off rack base peace
Damping due to rotation is filled, prevents uncoiling process inertia effects from producing, in a roll of unwrapping wire latter stage, by being welded to connect two coilings, weldering
Termination process can be shut down, and can also be welded under open state.The arc welding that welding is clamped using two ends, surface after welding
Grinder buffing is used again, and the larger steel grade welding position of stress is made annealing treatment at 400-600 DEG C.
S102 carries out mechanical Shot Blasting to the wire rod after unwrapping wire；
Dephosphorization is carried out to wire rod using mechanical Shot Blasting, to parallel multiply wire rod side by side, after such as 16-24 strands of unwrapping wire
Wire rod carry out concentration Shot Blasting, by reasonably design it is per share between spacing and shot-blasting machine spray angle, to optimize
The effect of mechanical descaling, such as, it is per share between spacing control in 150-180mm, scale removal effect is likely to be breached more than 95%.
S103 carries out protective atmosphere heating to the wire rod after de-scaling is handled；
Electrical heating or gas fired radiant tubes mode of heating can be used, heating furnace leads to methanol, nitrogen protective gas, is formed
Weak reducing atmosphere, prevents the wire rod surface after de-scaling from continuing to produce iron scale and depth decarburization, Fig. 2 is implemented for the present invention one
The time-temperature figure of the offline production of example high-carbon steel wire rod.
In this implementation heating power be 1680KW, 1050 DEG C of heating furnace rated temperature, thermal evenness controlling is ± 7.5
DEG C, heating furnace temperature-controlled precision ± 1 DEG C can be heated certain time for the big specification 16mm wire rods of the limit, a sections in such as Fig. 2, example
Such as 8 minutes, temperature was increased to a temperature in the range of 950-1050 DEG C, at such a temperature held for some time, the b sections in such as Fig. 2,
Such as 2 minutes.
S104 carries out isothermal hardening using salt bath to the wire rod after heating；
The hardening media of salt bath is potassium nitrate, sodium nitrate, hardening media is carried out according to the difference of specification and kind excellent
Change configuration, for example, constitute hardening media from 55% potassium nitrate and 45% sodium nitrate (percentage by weight), form high-temperature molten salt.Salt
Austempering temperature in bath is tried one's best, and holding is constant, and undulated control is at ± 5 DEG C；
Handled for different wire rod bodyization, can select temperature in different hardening heats, salt bath can be
Selected in the range of 200-550 DEG C.As shown in table 2, the hardening heat that sorbitizing handles selection is 450-550 DEG C, bainite
The hardening heat for handling selection is 200-400 DEG C.
Table 2
| Sorbitizing processing | Bainite processing | |
| Hardening heat | 450-550℃ | 200-400℃ |
The length of salt bath is in 10-15m in the present embodiment, and by controlling unwrapping wire speed in 3-5m/min, wire rod isothermal is quenched
The fiery time ensures c sections and d sections, for example, 3-5min in certain time such as Fig. 2., can be with for sorbitizing processing time
The appearance of center portion segregation tissue retained austenite and martensite is effectively reduced, while obtaining 0.15-0.2 μm of sorbite piece
Layer, is conducive to drawing deformation.
Water, weight hundred of the aqueous phase for water and hardening media gross weight can be added in the present embodiment in hardening media
Dividing can be adjusted than the temperature for 0.1%-0.68%, quenching according to the requirement of the structure property of variety steel.Control quenching is situated between
The water content of matter, can effectively change the cooling characteristics of high-temperature molten salt, the cooling speed of the fused salt influence wire rod of different moisture content
Rate.Saturated water content difference under different temperatures inside high-temperature molten salt of the present invention is larger, in the range of 450-550 DEG C,
Saturated water content is in the range of 0.1-0.68%, by rationally controlling the saturation degree of water, can effectively control to quench wire rod
Cooldown rate.The structure property of cooldown rate and 14mm prestressed wire rods under different saturated water contents is as shown in table 3 below.
Table 3
S105 carries out surface clean to the wire rod after isothermal hardening；
Surface clean is carried out to the wire rod after quenching using 27-50 DEG C of water of temperature, cleaning is divided into three-level cleaning, passes through control
Make the cleaning water pressure per one-level to control cleaning performance and wire rod temperature drop, the parameter of specific three-level cleaning is as shown in table 4.3rd
Wire rod temperature control after level cleaning prevents Quench and surface residual structural stress, is the later stage in the range of 350-450 DEG C
Wire rod winding Zona transformans carrys out difficulty.To carry out sealing gland to cooling water by using annular recoil air after three-level cleaning, will clean
The residual water on the surface of wire rod is cleaned up afterwards, the surface stress for preventing remaining water from bringing.
Table 4
| First order water | Second level water | Third level water | Blowback air | |
| Pressure | 0.5Mpa | 0.4Mpa | 0.3Mpa | 0.5Mpa |
S106 is to the wire rod take-up after cleaning.
Added using vertical take-up and the vertical bar handled is collected, the coiling internal diameter 900mm after collection, external diameter
1350mm.Plum blossom-shaped collecting effect is formed by controlling admission machine and collecting the speed difference of machine, the collection coiled is improved fine and close
Property, the height coiled is reduced, admission machine and the speed difference for collecting machine are 0.15-0.2m/m.
The method of the present invention can be applied to be obtained in production bridge zinc-coated wire offline with gren rod.The production of single line
Ability is at 30,000 tons, and producing line is using 24 bursts of designs.
Experimental example 1
13mm zinc-coated wire gren rods are produced, the wire rod tensile strength of production reaches 1370Mpa, meets intensity rank
The 5mm zinc-coated wires requirement of 1860Mpa ranks.Specifically include following steps
Unwrapping wire is carried out to initial steel wire rod, unwrapping wire speed control is in 4m/min, and welding position makes annealing treatment at 400 DEG C；
Mechanical Shot Blasting is carried out to the wire rod after unwrapping wire, per share spacing control is in 160mm, and ball blast scale removal effect reaches
95%；
Protective atmosphere heating is carried out to the wire rod after de-scaling is handled, thermal evenness controlling is at ± 7.5 DEG C, heating
Stove temperature-controlled precision ± 1 DEG C, wire rod heats 8 minutes temperature and is increased to 950 DEG C, and 2 minutes are incubated at 950 DEG C；
Isothermal hardening is carried out to the wire rod after heating using salt bath, salt temperature is controlled at 520 DEG C, and water content exists
0.1%；
Surface clean is carried out to the wire rod after isothermal hardening, wire rod temperature reaches 400 DEG C after cleaning；
To the wire rod take-up after cleaning, the speed difference of lapper and collection machine is controlled in 0.15m/min.
Experimental example 2
14mm zinc-coated wire gren rods are produced, the wire rod tensile strength of production reaches 1400Mpa, meets intensity rank
The 5mm zinc-coated wires requirement of 1960Mpa ranks.
Unwrapping wire is carried out to initial steel wire rod, unwrapping wire speed control is in 3m/min, and welding position makes annealing treatment at 500 DEG C.
Mechanical Shot Blasting is carried out to the wire rod after unwrapping wire, per share spacing control is in 150mm, and ball blast scale removal effect reaches
95%.
Protective atmosphere heating is carried out to the wire rod after de-scaling is handled, thermal evenness controlling is at ± 7.5 DEG C, heating
Stove temperature-controlled precision ± 1 DEG C, wire rod heats 8 minutes temperature and is increased to 1050 DEG C, and 2 minutes are incubated at 1050 DEG C.
Isothermal hardening is carried out to the wire rod after heating using salt bath, salt temperature is controlled at 500 DEG C, and water content exists
0.15%.
Surface clean is carried out to the wire rod after isothermal hardening, wire rod temperature reaches 420 DEG C after cleaning.
To the wire rod take-up after cleaning, the speed difference of lapper and collection machine is controlled in 0.2m/min.
It should be noted that in accompanying drawing or specification text, the implementation for not illustrating or describing is affiliated technology
Form known to a person of ordinary skill in the art, is not described in detail in field.In addition, the above-mentioned definition to each element and method is simultaneously
It is not limited only to various concrete structures, shape or the mode mentioned in embodiment.
It should also be noted that, the demonstration of the parameter comprising particular value can be provided herein, but these parameters are without definite etc.
In corresponding value, but analog value can be similar in acceptable error margin or design constraint.
Particular embodiments described above, has been carried out further in detail to the purpose of the present invention, technical scheme and beneficial effect
Describe in detail bright, it should be understood that the foregoing is only the present invention specific embodiment, be not intended to limit the invention, it is all
Within the spirit and principles in the present invention, any modification, equivalent substitution and improvements done etc. should be included in the protection of the present invention
Within the scope of.
It should be noted that in accompanying drawing or specification text, the implementation for not illustrating or describing is affiliated technology
Form known to a person of ordinary skill in the art, is not described in detail in field.In addition, the above-mentioned definition to each element and method is simultaneously
Various concrete structures, shape or the mode mentioned in embodiment are not limited only to, those of ordinary skill in the art can carry out letter to it
Singly change or replace.
Claims (10)
1. a kind of offline production method of high-carbon steel wire rod, wherein, including：
Protective atmosphere heating is carried out to wire rod；
Isothermal hardening is carried out to the wire rod after heating using salt bath；And
To the wire rod take-up after isothermal hardening.
2. offline production method according to claim 1, wherein, wire rod is carried out also to wrap before protective atmosphere heating
Include：
Unwrapping wire is carried out to initial steel wire rod；And
The wire rod obtained to unwrapping wire carries out mechanical Shot Blasting.
3. offline production method according to claim 1, wherein, isothermal is carried out to the wire rod after heating using salt bath and quenched
Fire and to also including between the wire rod take-up after isothermal hardening：
Surface clean is carried out to the wire rod after isothermal hardening.
4. offline production method according to claim 1, wherein, during the progress protective atmosphere heating to wire rod, disk
Bar is warming up to 950-1050 DEG C, and is kept for about 2 minutes in said temperature.
5. offline production method according to claim 1, wherein, the hardening media of the salt bath is potassium nitrate, nitric acid
Sodium.
6. offline production method according to claim 5, wherein, it is 55% that the hardening media, which includes percentage by weight,
Potassium nitrate and 45% sodium nitrate.
7. offline production method according to claim 5, wherein, the austempering temperature is 450-550 DEG C, and isothermal is quenched
The fiery time is 3-5min.
8. offline production method according to claim 5, wherein, water, institute are added during the isothermal hardening in hardening media
It is 0.1%-0.68% for water and the percentage by weight of hardening media gross weight to state aqueous phase.
9. offline production method according to claim 5, wherein, the isothermal hardening is sorbitizing processing.
10. offline production method according to claim 3, wherein, the cleaning uses 27-50 DEG C of water, through over cleaning
The temperature of wire rod afterwards is maintained at 350-450 DEG C.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710371157.9A CN107254568A (en) | 2017-05-23 | 2017-05-23 | The offline production method of high-carbon steel wire rod |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710371157.9A CN107254568A (en) | 2017-05-23 | 2017-05-23 | The offline production method of high-carbon steel wire rod |
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| Publication Number | Publication Date |
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| CN107254568A true CN107254568A (en) | 2017-10-17 |
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| CN201710371157.9A Pending CN107254568A (en) | 2017-05-23 | 2017-05-23 | The offline production method of high-carbon steel wire rod |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108103282A (en) * | 2018-01-23 | 2018-06-01 | 北京建通鸿翔科技有限公司 | A kind of wire rod heat-treatment technology method |
| CN111560510A (en) * | 2020-04-23 | 2020-08-21 | 中国重型机械研究院股份公司 | Steel pipe heat treatment quenching method |
| WO2021098451A1 (en) * | 2019-11-19 | 2021-05-27 | 江苏中天科技股份有限公司 | Preparation method for coated alloy wire |
Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104294148A (en) * | 2014-09-22 | 2015-01-21 | 武汉钢铁(集团)公司 | High-strength zinc-coated strapping belt and production method thereof |
| CN106636581A (en) * | 2016-11-30 | 2017-05-10 | 青岛特殊钢铁有限公司 | Salt bath treatment method and equipment for wire rod for 1960 MPa and above bridge cable zinc-coated steel wire |
-
2017
- 2017-05-23 CN CN201710371157.9A patent/CN107254568A/en active Pending
Patent Citations (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN104294148A (en) * | 2014-09-22 | 2015-01-21 | 武汉钢铁(集团)公司 | High-strength zinc-coated strapping belt and production method thereof |
| CN106636581A (en) * | 2016-11-30 | 2017-05-10 | 青岛特殊钢铁有限公司 | Salt bath treatment method and equipment for wire rod for 1960 MPa and above bridge cable zinc-coated steel wire |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108103282A (en) * | 2018-01-23 | 2018-06-01 | 北京建通鸿翔科技有限公司 | A kind of wire rod heat-treatment technology method |
| WO2021098451A1 (en) * | 2019-11-19 | 2021-05-27 | 江苏中天科技股份有限公司 | Preparation method for coated alloy wire |
| CN111560510A (en) * | 2020-04-23 | 2020-08-21 | 中国重型机械研究院股份公司 | Steel pipe heat treatment quenching method |
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