CN101264507A - Steel-forged ball processing technique - Google Patents
Steel-forged ball processing technique Download PDFInfo
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- CN101264507A CN101264507A CNA2008103014782A CN200810301478A CN101264507A CN 101264507 A CN101264507 A CN 101264507A CN A2008103014782 A CNA2008103014782 A CN A2008103014782A CN 200810301478 A CN200810301478 A CN 200810301478A CN 101264507 A CN101264507 A CN 101264507A
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Abstract
The invention discloses a forging steel ball processing technology, which facilitates the control over the quality over forging steel ball in processing; the processing technology comprises the following steps: a. steel billet selection; b. material cutting; c. air hammer fracturing material; d. the steel billet is heated to 1050 DEG C to 1150 DEG C by using an intermediate frequency induction electric stove; e. air hammer die forging; f. a forged and molded steel ball is precooled; g. the precooled steel ball is quenched by using warm water of 30 DEG C to 60 DEG C; h. a liquid medium is used for tempering; the tempering temperature is 180 to 240 DEG C; the time is 3 to 10 hours; i. the steel ball is air-cooled to ambient temperature. By adopting the processing technology, the processing technology has the advantages that the steel billet use range can be expended greatly, and the control over the production process is facilitated; the case hardness of the produced steel ball can reach HRC 50-64; the core rigidity can reach HRC 40-50; the steel ball wearing can be reduced by 30 to 75%; the service life is greatly increased; therefore, the processing technology is suitable for popularizing in production and processing of grinding steel ball.
Description
Technical field
The present invention relates to a kind of steel-forged ball processing technique method, the steel-forged ball processing technique that adopts when especially relating to a kind of production mine ore grinding with steel ball.
Background technology
The forged steel ball is widely used on the ball mills such as metallurgy, coloured, chemical industry, building materials, steam power plant, the patent No. is the patent of ZL96102787.8, and its processing technology of producing the forged steel ball comprises: select steel billet, earnestly blanking, coal combustion heating steel billet, pneumatic hammer die forging, precooling, quenching, tempering, air cooling, wash ball and warehouse-in.Steel billet carbon containing 0.78~0.90%, silicon 0.75~0.85%, manganese 0.85~0.95%, sulphur are less than or equal to 0.05%, phosphorus is less than or equal to 0.05%.This process has following shortcoming: adopt fervent blanking, cause the steel ball burning to cause the skin decarburization phenomenon easily; Adopt coal-fired mode to steel ball heat be by the outside to internal heat transfer, its heat time heating time and difficult control of temperature (being generally heat time heating time 3~5 hours), and pollute easily, the yield rate that heating is come out is lower; Steel ball water temperature when quenching is lower than 30 ℃, causes steel ball to burst easily, the percentage of damage height; And the one-tenth of existing steel ball is grouped into and has determined that when quenching steel ball is difficult for the core that a step is quenched into steel ball, is unfavorable for the refinement to texture.
Summary of the invention
Technical problem to be solved by this invention provides a kind of in process, is convenient to control the steel-forged ball processing technique of forged steel ball quality.
The technical solution adopted for the present invention to solve the technical problems is: steel-forged ball processing technique may further comprise the steps: a selects steel billet; The b cutting stock; C pneumatic hammer fracture; D is heated to 1050 ℃~1150 ℃ with steel billet; The die forging of e pneumatic hammer; The f precooling has forged the steel ball of moulding; Steel ball after g adopts warm water to precooling quenches; H adopts liquid medium tempering, 180~240 ℃ of temperatures, 3~10 hours time; The i air cooling is characterized in that to room temperature: adopt medium-frequency induction furnace to heat in the steps d, adopt 30 ℃~60 ℃ warm water in the step g.
Further be that described steel billet carbon containing 0.7~0.95%, silicon 0.11~1.25%, manganese 0.75~0.95%, sulphur are less than or equal to 0.035%, phosphorus is less than or equal to 0.035%, vanadium 0.07~0.12% and other alloy.
Further be that after room temperature, the gaza is cleaned the remaining medium of steel ball surface in mixer, selects brokenly ball at air cooling.
As optimized technical scheme, in step b, adopt CUT cold cut blanking.
As optimized technical scheme, the steel ball that will forge moulding in step f is pre-chilled to 730~830 ℃.
As optimized technical scheme, tempering liquid medium in step h adopts the pitch of fusing, No. 50~No. 100 machinery oil, H
2Tempering oil, potassium nitrate or sodium nitrate solution.
As optimized technical scheme, to have forged the steel ball of moulding be to have on the iron plate of through hole to carry out precooling in precooling in step f.
The invention has the beneficial effects as follows: adopt medium-frequency induction furnace that steel billet is heated, make steel billet by inside to external heat transfer, can effectively prevent the steel billet burning, thereby can reduce the percentage of damage of steel ball greatly, and can shorten heat time heating time greatly, in heating-up temperature and all easy to control on heat time heating time; And in steel billet, add micro-vanadium, and can make steel ball when quenching, settle at one go and be quenched into core, be beneficial to the texture of refinement steel ball inside; This process production phosphorus content is 0.7~0.95%, the steel billet of silicon 0.11~1.25% but adopt, the scope of available steel billet can increase greatly, and its case hardness of the steel ball of producing all can reach HRC50~64, and core hardness reaches HRC40~50, and the impact flexibility surface can reach 12J/cm
2, core is 15J/cm
2, and when ore dressing, the steel ball abrasion can reduce by 30~75%, improve service life greatly, are particluarly suitable for promoting the use of in the production and processing of ore grinding with steel ball.
The specific embodiment
The invention will be further described below in conjunction with embodiment.
Steel-forged ball processing technique of the present invention may further comprise the steps:
A selects steel billet; Select that phosphorus content is 0.7~0.95%, silicon 0.11~1.25%, manganese 0.75~0.95%, sulphur are less than or equal to 0.035%, phosphorus is less than or equal to 0.035%, the steel billet of vanadium 0.07~0.12% and other alloy, if the mixing steel billet is arranged, need to remove; Have the heavy metal segregation in the steel billet simultaneously, also should selecting to the greatest extent of " hard core " or crackle arranged, and hydrogen content avoids causing brokenly ball less than 3/1000000ths in the steel billet.In steel billet, add 0.07~0.12% vanadium in addition, can make steel ball when quenching, settle at one go and be quenched into core, be beneficial to the texture of refinement steel ball inside.
The b cutting stock; Obtain a steel billet that steel ball is required.Preferably adopt CUT cold cut blanking, avoid adopting the blank surface decarburization phenomenon of fervent blanking formation, and the CUT cutting can make cutting environment clean, pollution-free.
C pneumatic hammer fracture; Can make the steel ball size that forges within the margin of tolerance that allows.
D is heated to 1050 ℃~1150 ℃ with steel billet; Adopt medium-frequency induction furnace to heat in the heating process, make steel billet by inside to external heat transfer, steel billet Controllable Temperature from the inside to the outside can effectively prevent the steel ball burning built in 1050 ℃~1150 ℃, thereby can reduce the percentage of damage of steel ball greatly.During heating, per two of the steel ball of diameter below 80mm 7~8 seconds, the above steel ball of 100mm 9~16 seconds each, shorten heat time heating time greatly, brings up to the steel ball of producing more than 12 tons in per 8 hours by producing 3~4 tons of steel balls in former per 8 hours.
The die forging of e pneumatic hammer; Make steel ball obtain good density and circularity, when die forging, the following steel ball of diameter 50mm adopts the 65KG pneumatic hammer, and the steel ball of 60~100mm adopts the 150KG pneumatic hammer, the steel ball of 110~125mm adopts the 250KG pneumatic hammer, the steel ball 650KG pneumatic hammer that 130mm is above.
The f precooling has forged the steel ball of moulding; In the last step, the steel ball initial forging temperature is in 1150 ℃, and final forging temperature must be chilled to 730~830 ℃ in advance from 880 ℃ with steel ball and reenter water-quenching more than 880 ℃.And precooling is preferably in and carries out precooling on the iron plate with through hole, and the bulk temperature of being convenient to steel ball is pre-chilled to 730~830 ℃.
Steel ball after g adopts warm water to precooling quenches; According to the size of sphere diameter, quenching bath should have enough capacity; Water will long stream, is using water wisely, and water requires to recycle repeatedly; The length requirement of quenching bath is more than 10 meters; Because same ball hardness is inhomogeneous, steel ball can become the spill ball in the ore grinding, can cause great influence to ore grinding, puts the drum-type quenching unit of a low speed rotation in quenching bath, can improve the integral hardness of steel ball so greatly; The temperature of warm water is controlled at 30 ℃~60 ℃, and hardening heat is lower than 30 ℃, and steel ball bursts easily, and the percentage of damage height is higher than 60 ℃, and ball hardness can not reach requirement again; In addition, hardening media preferably adopts clear water, can not have suds, washing powder water or oil impurities to sneak into, to avoid water quality deterioration.
H adopts liquid medium tempering, 180~240 ℃ of temperatures, 3~10 hours time; The internal stress that produces after steel ball quenches is eliminated by tempering.Temperature is decided according to the content of silicon in the steel, and temperature is limited to 180~240 ℃, tempering time 3~10 hours; Temper medium changes air dielectric commonly used into liquid medium, for example Rong Hua pitch, No. 50~No. 100 machinery oil, H
2Tempering oil, potassium nitrate or sodium nitrate solution etc.And when tempering vessel in heating temper medium, change electric heater for heating into by the coal heating, and adopt instrument control temperature and time, thoroughly solve the randomness of coal heating, be beneficial to control tempering time and temperature; The tempering container seals during heating, prevents the pernicious gas contaminated air, and the gas that is discharged in the heating process passes through air exhauster suction circulating line, and cools off in the feeding pond, temper medium can be recycled, and has both solved pollution, has reduced cost again.After adopting this tempering process, the case hardness of steel ball all can reach HRC50~64, and core hardness reaches HRC40~50, and metallographic structure is the heterogeneous structure of tempered martensite and bainite, steady quality, and impact flexibility is good, and is antiacid, corrosion-resistant, heat-resisting, wear-resisting.
The i air cooling is to room temperature.After tempering time reaches, steel ball is taken out air cooling to room temperature from the tempering container.
For improving the quality of steel ball, after room temperature, the gaza is cleaned the remaining medium of steel ball surface in mixer, selects brokenly ball at air cooling.After through this step, just round rate height did not have broken ball when steel ball turned round in ball mill, can reach the ore milling concentration and the fineness that improve the ore dressing plant, treating capacity and running rate when the rate of recovery of raising concentrate, the platform of grinding machine reduce unit consumption, energy savings and reach the purpose that reduces the ore grinding cost.
Embodiment 1: choose carbon content and be 0.7%, the steel billet of silicon 0.11%, manganese 0.75%, vanadium 0.07% and other alloy; With CUT cold cut blanking; The pneumatic hammer fracture; Adopt medium-frequency induction furnace that steel billet is heated to 1050 ℃; The pneumatic hammer die forging; Precooling has forged the steel ball to 830 ℃ of moulding; Steel ball after adopting 30 ℃ warm water to precooling quenches; Adopt the liquid medium tempering, temperature is 180 ℃, 3 hours time; Air cooling is to room temperature; The gaza is cleaned the remaining medium of steel ball surface in mixer, selects brokenly ball.Through after this technology, the case hardness of steel ball reaches HRC50~52, and core hardness reaches HRC40~42, and the impact flexibility surface reaches 12J/cm2, and core is 15J/cm2, and when using in ore dressing, the steel ball abrasion can reduce by 30~75%, and are up-to-standard.
Embodiment 2: choose carbon content and be 0.85%, the steel billet of silicon 0.60%, manganese 0.85%, vanadium 0.09% and other alloy; With CUT cold cut blanking; The pneumatic hammer fracture; Adopt medium-frequency induction furnace that steel billet is heated to 1100 ℃; The pneumatic hammer die forging; Precooling has forged the steel ball to 850 ℃ of moulding; Steel ball after adopting 40 ℃ warm water to precooling quenches; Adopt the liquid medium tempering, temperature is 220 ℃, 7 hours time; Air cooling is to room temperature; The gaza is cleaned the remaining medium of steel ball surface in mixer, selects brokenly ball.Through after this technology, the case hardness of steel ball reaches HRC52~54, and core hardness reaches HRC42~44, and the impact flexibility surface reaches 12J/cm2, and core is 15J/cm2, and when using in ore dressing, the steel ball abrasion can reduce by 30~75%, and are up-to-standard.
Embodiment 3: choose carbon content and be 0.95%, the steel billet of silicon 1.25%, manganese 0.95%, vanadium 0.12% and other alloy; With CUT cold cut blanking; The pneumatic hammer fracture; Adopt medium-frequency induction furnace that steel billet is heated to 1150 ℃; The pneumatic hammer die forging; Precooling has forged the steel ball to 880 ℃ of moulding; Steel ball after adopting 60 ℃ warm water to precooling quenches; Adopt the liquid medium tempering, temperature is 240 ℃, 10 hours time; Air cooling is to room temperature; The gaza is cleaned the remaining medium of steel ball surface in mixer, selects brokenly ball.Through after this technology, the case hardness of steel ball reaches HRC58~62, and core hardness reaches HRC44~50, and the impact flexibility surface reaches 12J/cm2, and core is 15J/cm2, and when using in ore dressing, the steel ball abrasion can reduce by 30~75%, and are up-to-standard.
Claims (7)
1. steel-forged ball processing technique, may further comprise the steps: a selects steel billet; The b cutting stock; C pneumatic hammer fracture; D is heated to 1050 ℃~1150 ℃ with steel billet; The die forging of e pneumatic hammer; The f precooling has forged the steel ball of moulding; Steel ball after g adopts warm water to precooling quenches; H adopts liquid medium tempering, 180~240 ℃ of temperatures, 3~10 hours time; The i air cooling is characterized in that to room temperature: adopt medium-frequency induction furnace to heat in the steps d, adopt 30 ℃~60 ℃ warm water in the step g.
2. steel-forged ball processing technique as claimed in claim 1 is characterized in that: described steel billet carbon containing 0.7~0.95%, silicon 0.11~1.25%, manganese 0.75~0.95%, sulphur are less than or equal to 0.035%, phosphorus is less than or equal to 0.035%, vanadium 0.07~0.12% and other alloy.
3. steel-forged ball processing technique as claimed in claim 1 or 2 is characterized in that: in the i step, air cooling is after room temperature, and the gaza is cleaned the remaining medium of steel ball surface in mixer, selects brokenly ball.
4. steel-forged ball processing technique as claimed in claim 1 or 2 is characterized in that: adopt CUT cold cut blanking in step b.
5. steel-forged ball processing technique as claimed in claim 1 or 2 is characterized in that: the steel ball that will forge moulding in step f is pre-chilled to 730~830 ℃.
6. steel-forged ball processing technique as claimed in claim 1 or 2 is characterized in that: the tempering liquid medium in step h adopts pitch, No. 50~No. 100 machinery oil, H2 tempering oil, potassium nitrate or sodium nitrate solutions of fusing.
7. steel-forged ball processing technique as claimed in claim 1 or 2 is characterized in that: to have forged the steel ball of moulding be to have on the iron plate of through hole to carry out precooling in precooling in step f.
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CN102489646A (en) * | 2011-12-23 | 2012-06-13 | 攀枝花钢城集团瑞矿工业有限公司 | Method for processing steel ball |
CN102560021A (en) * | 2012-02-17 | 2012-07-11 | 南车四方车辆有限公司 | Heat treatment method for 40Cr wearing plate |
CN103014289A (en) * | 2013-01-09 | 2013-04-03 | 米易华星钒钛科技有限责任公司 | Manufacturing method of forged steel balls |
CN103614528A (en) * | 2013-12-12 | 2014-03-05 | 攀枝花钢城集团瑞矿工业有限公司 | Forging method of producing steel balls with phi 150-180mm by adopting round steel with phi 110mm |
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CN1044389C (en) * | 1996-03-28 | 1999-07-28 | 刘机 | Steel ball making process |
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CN102489646A (en) * | 2011-12-23 | 2012-06-13 | 攀枝花钢城集团瑞矿工业有限公司 | Method for processing steel ball |
CN102560021A (en) * | 2012-02-17 | 2012-07-11 | 南车四方车辆有限公司 | Heat treatment method for 40Cr wearing plate |
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CN103862230A (en) * | 2012-12-17 | 2014-06-18 | 黄望业 | Process for manufacturing excavator bucket teeth |
CN103014289A (en) * | 2013-01-09 | 2013-04-03 | 米易华星钒钛科技有限责任公司 | Manufacturing method of forged steel balls |
CN103014289B (en) * | 2013-01-09 | 2014-04-09 | 米易华星钒钛科技有限责任公司 | Manufacturing method of forged steel balls |
CN103614528A (en) * | 2013-12-12 | 2014-03-05 | 攀枝花钢城集团瑞矿工业有限公司 | Forging method of producing steel balls with phi 150-180mm by adopting round steel with phi 110mm |
CN107447095A (en) * | 2017-08-09 | 2017-12-08 | 侯宇岷 | A kind of method for producing abrasion-proof steel ball |
CN107553141A (en) * | 2017-09-05 | 2018-01-09 | 四川鸿舰重型机械制造有限责任公司 | Full-automatic more specifications extrude round as a ball grinding ball production |
CN110819897A (en) * | 2019-11-14 | 2020-02-21 | 伊莱特能源装备股份有限公司 | Material and method suitable for producing large-diameter wear-resistant steel balls of semi-autogenous mill |
CN110819897B (en) * | 2019-11-14 | 2021-08-31 | 伊莱特能源装备股份有限公司 | Material and method suitable for producing large-diameter wear-resistant steel balls of semi-autogenous mill |
CN112775371A (en) * | 2020-12-18 | 2021-05-11 | 山东东铁铸锻有限公司 | High-automation forged ball production process |
CN114850365A (en) * | 2022-04-19 | 2022-08-05 | 中国恩菲工程技术有限公司 | Bainite-based grinding medium and preparation method and application thereof |
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