CN107350303A - A kind of production method of automobile axial workpiece steel - Google Patents

A kind of production method of automobile axial workpiece steel Download PDF

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Publication number
CN107350303A
CN107350303A CN201710426163.XA CN201710426163A CN107350303A CN 107350303 A CN107350303 A CN 107350303A CN 201710426163 A CN201710426163 A CN 201710426163A CN 107350303 A CN107350303 A CN 107350303A
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China
Prior art keywords
rolling
blank
finished product
middle base
steel
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CN201710426163.XA
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CN107350303B (en
Inventor
顾铁
邵淑艳
李英
颉军定
章照
周阳
高峰
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Jiangyin Xingcheng Special Steel Works Co Ltd
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Jiangyin Xingcheng Special Steel Works Co Ltd
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/04—Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of bars or wire
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B21—MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21C—MANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C51/00—Measuring, gauging, indicating, counting, or marking devices specially adapted for use in the production or manipulation of material in accordance with subclasses B21B - B21F

Abstract

The present invention relates to a kind of production method of automobile axial workpiece steel, using big cross section rectangular billet CC as raw material, become a useful person technique using two fire, ensure split rolling method and the compression ratio of finished product rolling, big compression ratio is used when particularly finished product rolls, compression ratio >=30, to control hot rolling material decarburized layer deepness and surface defect depth.Technological process, smelting → continuous casting → split rolling method+scafing → middle base flaw detection reconditioning → middle base finished product rolling → finished product flaw detection.The application has produced a kind of decarburized layer is shallow, surface quality is high, dimensional accuracy is high hot rolling material to substitute bright as silver processing, is easy to the direct blanking processing and forming of client.

Description

A kind of production method of automobile axial workpiece steel
Technical field
The present invention relates to a kind of production method of auto parts steel, more particularly to one kind to substitute bright as silver rod with hot rolled rod The production method of material.
Background technology
In order to save the energy, improve stock utilization, reduction production cost, automobile axial workpiece carries out forming machine to material section Smaller processing capacity, or even zero processing capacity need to be used during processing, that is, expect section in processing and forming part surface processing less than.Generally It is required that material section surface depth of defect≤0.1mm, out-of-roundness≤0.15mm.In general hot rolling material is due to the limitation of working condition, very Difficulty reaches above-mentioned requirements.Generally for meeting above-mentioned requirements, raw material bar is carried out under need to carrying out after bright as silver processing again into material section Shaping machining.It is bright as silver processing be hot rolled rod is aligned, turning is refined again, with remove or lightening material decarburization, split Line, the surface defects such as skin are stuck up, while improve scantling precision, to meet part processing request.But thus will certainly be big It is big to reduce stock utilization, production efficiency is reduced, increases production cost.And specification is smaller, the proportion of goods damageds of material during bright as silver processing In elevated trend.It is bright as silver with hot rolling replacement for specification limit≤Φ 60mm material, remove bright as silver process, cost from It is with the obvious advantage.
To sum up, in order to adapt to low consumption environmental protection, the modern production requirement of high-efficiency and economic, a kind of surface quality can be produced It is high, dimensional accuracy is high, the good hot rolled rod of internal soundness, by hot rolled rod it is direct under into carrying out forming machine processing to save after material section Bar is gone to need additionally to carry out the step sequence of bright as silver processing before processing.
The content of the invention
Present invention aims at the production method of a kind of great surface quality of offer, the hot rolled rod of high dimensional accuracy.It is applicable In production specification scope≤Φ 60mm bar, to save the bright as silver material of client this process.
Technical scheme is used by the present invention solves the above problems：A kind of production method of automobile axial workpiece steel, with Big cross section rectangular billet CC is raw material, is become a useful person technique using two fire, it is ensured that split rolling method and the compression ratio of finished product rolling, particularly Finished product uses big compression ratio, compression ratio >=30, to control hot rolling material decarburized layer deepness and surface defect depth when rolling.
Specifically, technological process, smelting → continuous casting → split rolling method+scafing → middle base flaw detection reconditioning → middle base Finished product rolling → finished product flaw detection, concrete operations are as follows
1）Smelt
According to chemical composition corresponding to the performance of steel grade and the design of the requirement of user, through converter or electric furnace smelting, subsequent LF External refining, smelt and meet the molten steel of steel chemical composition, each chemical element of stability contorting, using high-performance refined synthetic slag, The quantity and form of each type impurity of steel are controlled, improves steel degree of purity, Fruit storage is carried out to molten steel afterwards；Remove The pernicious gases such as H, to meet steel performance requirement.
2）Continuous casting
Continuous casting billet is designed as rectangle bloom, casting blank section 390mm*510mm, using M-EMS, end electromagnetism Stirring, the segregation of slighter compress control material, using tundish sensing heating, be advantageous to the floating absorption of field trash, at the same it is controllable The system cast degree of superheat, realizes Prepared by Low Superheat Pouring, in favor of improving strand inside and surface quality.
3）Continuous casting billet cogging
Blank is heated using step heating-furnace, selects corresponding heating cycle according to different steel grades, blank carries out surface after coming out of the stove Roughing after water under high pressure dephosphorization, carries out scafing to blank surface after roughing, scafing is to be covered with burning at rectangular billet four sides Mouth, hyperbaric oxygen air-flow being sprayed to blank surface, metal and the oxygen of blank surface react, and moment produces substantial amounts of heat, So that the metal melt of blank surface, the metal of thawing is taken away by hyperbaric oxygen air-flow, blank coating metal " melt and cut " is fallen, one side Certain depth is removed, typically 0.5-4mm, cleaning speed is 10~40m/min；Scafing can by blank surface oxide layer, Surface is stuck up the defects of skin, folding, crackle and effectively removed, with the middle base surface quality got well, be stocking skin decarburization and The control of surface defect lays the first stone.After scafing again finish rolling into the middle base size of design, the compression ratio control of split rolling method System is between 2~10；Through reciprocating roughing mill after open rolling, 8 passages of rolling are into 250mm*250mm, through scafing after roughing, then By 2 frame finish to gauge units, base among 200mm*200mm is rolled into.Start rolling temperature is 1000~1150 DEG C during split rolling method, eventually Temperature is rolled for 800~950 DEG C.
4）Middle base flaw detection reconditioning
Split rolling method will cheat slow cooling under blank in time after terminating, in order to avoid middle base cracks, slow cooling is entered after terminating to middle base Row surface inspection, and reconditioning removes blank surface defect.
5）Middle base finished product rolling
Blank is heated in walking beam furnace, corresponding heating cycle is selected according to different steel grades, for control surface decarburization, Blank total heat time is controlled, adds main thermal time≤4 hour, while controls heating-up temperature, soaking zone temperature≤1250 DEG C, it is ensured that Overall compression ratio >=30 of finished product rolling.Blank carries out surface high pressure water dephosphorization after coming out of the stove, afterwards successively through roughing → in roll → it is pre- The roller finish rolling of finish rolling → KOCKS tri- rolls into finished product round steel, in order to by finished size allowance control within ± 0.1 mm, no The mm of circularity≤0.15, the special pass of finish rolling specification is specially devised, i.e. designed finishing groove is served only for one rule of rolling Lattice.
6）Finished product is detected a flaw
Due to the inherent characteristic of hot rolled rod, stocking inevitably carries rolling defect, if surface defect is more than a depthkeeping Degree, it will influence to use, bright as silver material can not be substituted, so surface inspection need to be carried out to stocking, the material that flaw detection is not conformed to is carried out Scrap, or warehousing after passing is visited in reconditioning again, to ensure material surface quality.
Compared with prior art, the advantage of the invention is that：A kind of production method of automobile axial workpiece steel is provided, is adopted Become a useful person with two fire, use big cross section rectangular bloom during continuous casting, to realize the big compression ratio of split rolling method and finished product rolling, particularly into The compression ratio of product rolling is controlled >=30, to control hot rolling material decarburized layer deepness.During continuous casting billet split rolling method, used before finish rolling Scafing, blank surface defect is removed, fully removes blank surface oxide layer and harmful surface defect.And to middle base Surface inspection and finishing reconditioning are carried out, further removes middle blank surface defects.Finished product uses the roller finish rolling of KOCKS tri- when rolling, Ensure that stocking out-of-roundness meets to require.A hundred per cent surface inspection finally is carried out to mill product, it is ensured that finished product material surface defect Depth meets to require.In summary method, it is able to produce the hot rolling that a kind of decarburized layer is shallow, surface quality is high, dimensional accuracy is high Material is easy to the direct blanking processing and forming of client to substitute bright as silver processing.
Brief description of the drawings
Fig. 1 is middle base outward appearance picture in the production method of automobile axial workpiece steel of the present invention；
Fig. 2 is finished product material outward appearance picture in the production method of automobile axial workpiece steel of the present invention.
Embodiment
The present invention is described in further detail with reference to embodiments.
Explanation and specific embodiment are to a kind of producer of auto parts steel of the present invention below in conjunction with the accompanying drawings Method makes further explanation and description, but the explanation and illustration does not form improper restriction to technical scheme.
Embodiment 1
A kind of production method of auto parts steel in the embodiment of the present invention 1 is manufactured by following process, particular use is manufacture vapour Car constant velocity cardan joint（CVJ）Power transmission shaft, specification are Φ 29mm, and the part plays a part of being driven and supported, in order to prevent lubricating Liquid seepage, CVJ jackshafts need good gap with soft overcoat and coordinated, therefore it is required that material surface decarburization≤0.1mm, table Planar defect depth≤0.1mm, out-of-roundness≤0.15mm, the direct blanking shaping machining of user, in order to reach above-mentioned requirements, design Method is produced by below：
1）Smelt：100 tons of converters carry out external refining after smelting, and molten steel is again through Fruit storage, each chemical element quality Percentage strictly controls on request.
2）Continuous casting：390mm × 510mm rectangle bloom is casting continuously to form, using tundish sensing heating, control tundish pours It is 10~40 DEG C to note the degree of superheat.To control the segregation of material, using advanced M-EMS, end electromagnetic agitation, connect Cast slighter compress Advanced Equipment and technique.Gained continuous casting billet chemical composition percentage see the table below shown in 1：
Table 1.（Wt.%, surplus are Fe and other inevitable impurity elements）
Grade of steel C Si Mn S P Cr Mo Cu B O
XC30 0.30 0.25 0.75 0.018 0.010 0.15 0.02 0.02 0.0025 0.0008
3）Continuous casting billet cogging（Containing scafing）：By blank heating, heat time >=4h, start rolling temperature in walking beam furnace At 1050~1200 DEG C, blank carries out roughing after surface high pressure water dephosphorization after coming out of the stove, and through reciprocating roughing mill after open rolling, rolls for control 8 passages are made into 250mm*250mm, scafing is used after roughing.Blank coating metal " melt and cut " is fallen, one side removal 0.5~ 4mm, cleaning speed are 10~40m/min.By two passage finish rolling after scafing, it is rolled into the 200mm*200mm of design Between blank, split rolling method compression ratio be 5.Lower hole slow cooling as early as possible is needed after middle base cutting, enters to cheat temperature >=500 DEG C.
4）Middle base reconditioning flaw detection：Base among 200mm*200mm is subjected to 100% magnetic powder inspection, blank repaiied afterwards Grind to remove blank surface defect.Middle base outward appearance photo is shown in Fig. 1.
5）Middle base finished product rolling
When CVJ transmission axle-steel XC30 in above-described embodiment is rolled, using base among 200mm*200mm, Φ 29mm are rolled into Hot rolled circular steel, rolling uses the roller finish rolling of KOCKS tri-, specific finished product rolling technological parameter such as table 2 below institute than being 60, during finish rolling Show：
Table 2.（Heating, hot rolling specific process parameter table）
6）Finished product is detected a flaw
100% surface inspection is carried out to stocking, non-destructive testing standard is surface defect depth≤0.1mm, and the material that flaw detection is not conformed to is carried out Scrap, or warehousing after passing is visited in reconditioning again, to ensure material surface quality.
Key index detection is carried out to the CVJ power transmission shafts in above-described embodiment 1, it is as shown in table 3 below to measure result：
Table 3
As seen from Table 3, the skin decarburization in embodiment, surface defect depth, dimensional accuracy fully meet design requirement.
A kind of to sum up CVJ power transmission shafts XC30 hot-strips in embodiment 1, the power transmission shaft is with steel surface decarburized layer is shallow, surface Quality is high, and dimensional accuracy is high, in apparent good order and condition, as shown in Figure 2, is available for the direct blanking shaping machining of user.
It is pointed out that exemplified as above is only specific embodiment of the invention, it is clear that real the invention is not restricted to more than Example is applied, but there are many similar changes as needed.If those skilled in the art is direct from present disclosure All deformations are exported or associated, protection scope of the present invention all should be belonged to.

Claims (2)

  1. A kind of 1. production method of automobile axial workpiece steel, it is characterised in that：Using big cross section rectangular billet CC as raw material, using two Fire is become a useful person technique, it is ensured that split rolling method and the compression ratio of finished product rolling, big compression ratio, compression ratio is used when particularly finished product rolls >=30, to control hot rolling material decarburized layer deepness and surface defect depth.
  2. A kind of 2. production method of automobile axial workpiece steel, it is characterised in that：Technological process, smelting → continuous casting → split rolling method+ Scafing → middle base flaw detection reconditioning → middle base finished product rolling → finished product flaw detection, concrete operations are as follows
    1）Smelt
    According to chemical composition corresponding to the performance of steel grade and the design of the requirement of user, through converter or electric furnace smelting, subsequent LF External refining, smelt and meet the molten steel of steel chemical composition, each chemical element of stability contorting, using high-performance refined synthetic slag, Fruit storage is carried out to molten steel afterwards；
    2）Continuous casting
    Continuous casting billet is designed as rectangle bloom, casting blank section 390mm*510mm, using M-EMS, end electromagnetism Stirring, the segregation of slighter compress control material, using tundish sensing heating, adsorbed by be allowed inclusion floating, are protected using low overheat Shield cast；
    3）Continuous casting billet cogging
    Blank is heated using step heating-furnace, selects corresponding heating cycle according to different steel grades, blank carries out surface after coming out of the stove Roughing after water under high pressure dephosphorization, through reciprocating roughing mill after open rolling, 8 passages are rolled into 250mm*250mm；To blank surface after roughing Scafing is carried out, scafing is to be covered with burner at rectangular billet four sides, sprays hyperbaric oxygen air-flow, blank table to blank surface The metal in face reacts with oxygen, and moment produces substantial amounts of heat so that the metal melt of blank surface, the metal quilt of thawing Hyperbaric oxygen air-flow is taken away, and blank coating metal " melt and cut " is fallen, and one side removes certain depth, typically 0.5-4mm, clears up speed For 10~40m/min；Pass through 2 frame finish to gauge units after scafing again, be rolled into base among 200mm*200mm；Split rolling method When start rolling temperature be 1000~1150 DEG C, finishing temperature be 800~950 DEG C, into the middle base size of design, the pressure of split rolling method Contracting is than control between 2~10；
    4）Middle base flaw detection reconditioning
    Split rolling method will cheat slow cooling under blank in time after terminating, in order to avoid middle base cracks, slow cooling is entered after terminating to middle base Row surface inspection, and reconditioning removes blank surface defect；
    5）Middle base finished product rolling
    Blank is heated in walking beam furnace, corresponding heating cycle is selected according to different steel grades, for control surface decarburization, Blank total heat time, total heat time≤4 hour are controlled, while control heating-up temperature, soaking zone temperature≤1250 DEG C, it is ensured that Overall compression ratio >=30 of finished product rolling；Blank carries out surface high pressure water dephosphorization after coming out of the stove, afterwards successively through roughing → in roll → it is pre- The roller finish rolling of finish rolling → KOCKS tri- rolls into finished product round steel, in order to by finished size allowance control within ± 0.1 mm, no The mm of circularity≤0.15, the special pass of finish rolling specification is designed for bar；
    6）Finished product is detected a flaw
    Surface inspection is carried out to stocking, the material that flaw detection does not conform to is scrapped, or warehousing after passing is visited in reconditioning again, to ensure material Expect surface quality.
CN201710426163.XA 2017-06-08 2017-06-08 Production method of automobile shaft part steel Active CN107350303B (en)

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Application Number Priority Date Filing Date Title
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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110170631A (en) * 2019-05-24 2019-08-27 邯郸钢铁集团有限责任公司 Improve the control method of pinion steel small billet center segregation
CN111267118A (en) * 2020-03-02 2020-06-12 北京鼎新时代科技有限公司 Finishing platform of online composite finishing robot
CN112239835A (en) * 2020-10-28 2021-01-19 江苏沙钢集团有限公司 Preparation method of high-plasticity high-rigidity medium carbon steel anti-roll bar material for automobiles
CN112792126A (en) * 2020-12-18 2021-05-14 山东钢铁股份有限公司 Hot rolling method of bearing steel with large compression ratio

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JPS6195718A (en) * 1984-10-18 1986-05-14 Daido Steel Co Ltd Descaling method of steel material
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CN102626724A (en) * 2012-04-19 2012-08-08 常熟市异型钢管有限公司 Method for producing titanium alloy pipe
JP2012236215A (en) * 2011-05-12 2012-12-06 Daido Steel Co Ltd Surface inspection method and surface inspection device for scarfed steel material
CN104907352A (en) * 2015-05-20 2015-09-16 湖州华特不锈钢管制造有限公司 Condenser stainless steel pipe production method
CN106544597A (en) * 2016-10-18 2017-03-29 武汉钢铁股份有限公司 Ultra-thin ultra-wide steel for nuclear power pressure equipment plate and its manufacture method

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS6195718A (en) * 1984-10-18 1986-05-14 Daido Steel Co Ltd Descaling method of steel material
CN101787493A (en) * 2010-01-25 2010-07-28 广州市奥赛钢线科技有限公司 Novel high-strength, fatigue-resistant and non-decarburized alloy spring steel and preparation method of steel wire thereof
JP2012236215A (en) * 2011-05-12 2012-12-06 Daido Steel Co Ltd Surface inspection method and surface inspection device for scarfed steel material
CN102626724A (en) * 2012-04-19 2012-08-08 常熟市异型钢管有限公司 Method for producing titanium alloy pipe
CN104907352A (en) * 2015-05-20 2015-09-16 湖州华特不锈钢管制造有限公司 Condenser stainless steel pipe production method
CN106544597A (en) * 2016-10-18 2017-03-29 武汉钢铁股份有限公司 Ultra-thin ultra-wide steel for nuclear power pressure equipment plate and its manufacture method

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN110170631A (en) * 2019-05-24 2019-08-27 邯郸钢铁集团有限责任公司 Improve the control method of pinion steel small billet center segregation
CN111267118A (en) * 2020-03-02 2020-06-12 北京鼎新时代科技有限公司 Finishing platform of online composite finishing robot
CN112239835A (en) * 2020-10-28 2021-01-19 江苏沙钢集团有限公司 Preparation method of high-plasticity high-rigidity medium carbon steel anti-roll bar material for automobiles
CN112792126A (en) * 2020-12-18 2021-05-14 山东钢铁股份有限公司 Hot rolling method of bearing steel with large compression ratio

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