CN106077382A - A kind of high intensity 20CrMoNi duplex spur gear precise forming process and mould - Google Patents

A kind of high intensity 20CrMoNi duplex spur gear precise forming process and mould Download PDF

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Publication number
CN106077382A
CN106077382A CN201610437058.1A CN201610437058A CN106077382A CN 106077382 A CN106077382 A CN 106077382A CN 201610437058 A CN201610437058 A CN 201610437058A CN 106077382 A CN106077382 A CN 106077382A
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CN
China
Prior art keywords
gear
duplex
20crmoni
intensity
mould
Prior art date
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.)
Pending
Application number
CN201610437058.1A
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Chinese (zh)
Inventor
徐淑波
景财年
刘鹏
李嘉宁
林晓娟
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Shandong Jianzhu University
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Shandong Jianzhu University
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Publication date
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Priority to CN201610437058.1A priority Critical patent/CN106077382A/en
Publication of CN106077382A publication Critical patent/CN106077382A/en
Pending legal-status Critical Current

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Classifications

    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J1/00Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
    • B21J1/04Shaping in the rough solely by forging or pressing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J1/00Preparing metal stock or similar ancillary operations prior, during or post forging, e.g. heating or cooling
    • B21J1/06Heating or cooling methods or arrangements specially adapted for performing forging or pressing operations
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J13/00Details of machines for forging, pressing, or hammering
    • B21J13/02Dies or mountings therefor
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21JFORGING; HAMMERING; PRESSING METAL; RIVETING; FORGE FURNACES
    • B21J5/00Methods for forging, hammering, or pressing; Special equipment or accessories therefor
    • B21J5/02Die forging; Trimming by making use of special dies ; Punching during forging
    • B21J5/025Closed die forging
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21KMAKING FORGED OR PRESSED METAL PRODUCTS, e.g. HORSE-SHOES, RIVETS, BOLTS OR WHEELS
    • B21K1/00Making machine elements
    • B21K1/28Making machine elements wheels; discs
    • B21K1/30Making machine elements wheels; discs with gear-teeth
    • CCHEMISTRY; METALLURGY
    • C21METALLURGY OF IRON
    • C21DMODIFYING 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
    • C21D7/00Modifying the physical properties of iron or steel by deformation

Abstract

The present invention relates to a kind of high intensity 20CrMoNi duplex spur gear precise forming process and mould, particularly a kind of high intensity 20CrMoNi duplex spur gear precise forming process and Tool and Die Technology, for automobile and the change speed gear box of precision machine tool.Obtain nanometer high intensity 20CrMoNi blank by the channel pressings severe plastic deformation technology such as 45 ° of turnings, with Warm Extrusion cold-finishing combined precision manufacturing process by nanometer high intensity 20CrMoNi blank precision form for high-strength accurate duplex-gear gear member.The final accurate duplex-gear gear member surface smoothness obtained is high, non-scale, and final size precision is high, and shaping dies is long for service life simultaneously, stable working.Meanwhile, the high-strength accurate duplex-gear gear member accumulated deformation degree obtained by channel pressings severe plastic deformations such as 45 ° of turnings is high, and crystal grain is effectively refined, and duplex-gear gear member mechanical property is good.

Description

A kind of high intensity 20CrMoNi duplex spur gear precise forming process and mould
Technical field
The invention belongs to precise forming process and the Tool and Die Technology of a kind of gear, particularly a kind of high intensity 20CrMoNi is double Connection spur gear precise forming process and Tool and Die Technology, for automobile and the change speed gear box of precision machine tool.
Background technology
Mostly using traditional cutting working method in traditional Gear Production, stock utilization is low, and product cost is high.With Market gear product performance and cost requirement are improved constantly, due to the high manufacturing cost of cutting working method and adding of the end Work efficiency rate, this makes people that attention is forwarded to some new manufacturing process.
Spur gear precise forming process and mould, to produce as far as possible close to the product of gear net shape, carry the most completely It is target for finished gear part, not only there is the significant advantage such as material-saving, energy-conservation, low cost, and the power of gear can be improved Learn performance and processing characteristics.
In 20CrMoNi duplex spur gear precise forming process and mould, first pass through severe plastic deformation technology and obtain Nanometer high intensity 20CrMoNi blank, uses Warm Extrusion cold-finishing combined precision manufacturing process to manufacture close to gear part shape Fine forge piece, the forging precision that the single manufacturing process such as more traditional flashless precision, forge hot and cold forging obtains is higher, shaping load Less higher with practicality.In warm extrusion technology, use blocking and finish-forging two-step process, make the forming technology of duplex spur gear Property be improved, simultaneously use center shunting technique reduce forging load, improve die life.During cold-finishing 20CrMoNi duplex spur gear machine parts'precise cold-finishing shaping is achieved by floating cavity die method.Above-mentioned new technology makes 20CrMoNi The precision form of duplex spur gear has higher production efficiency, it is thus achieved that the mechanical property of part get a greater increase, because of This, the precise forming process of spur gear and mould have brighter use value and development prospect.
Summary of the invention
The purpose of patent of the present invention is: for the problems referred to above, the height reducing the processing of 20CrMoNi duplex spur gear is manufactured into Basis and the working (machining) efficiency at the end.First it is to obtain nanometer high intensity by channel pressings severe plastic deformation technology such as 45 ° of turnings 20CrMoNi blank, with Warm Extrusion cold-finishing combined precision manufacturing process by nanometer high intensity 20CrMoNi blank precision form The consumption of the material energy is decreased for high-strength accurate duplex-gear gear member.Use forging produce gear, not only have material-saving, The significant advantage such as energy-conservation, low cost and high efficiency, and contribute to being internally formed densification, uniform nanometer Ultra-fine Grained at gear Grain tissue, has the most reasonably metal streamline along tooth profile, forms Surface Machining hardened layer and the tooth root of rounding off, from And it is greatly improved ability wear-resistant, erosion-resisting and the bending strength of root of gear, hence it is evident that improve the fatigue behaviour of gear.
In order to solve above-mentioned technical problem, the technical scheme of patent of the present invention is: one 20CrMoNi duplex of the present invention is straight Gear precision forming technology and mould, including set-up procedure, the pre-forging process of Warm Extrusion, Warm Extrusion finish-forging process and the precision of blank Four corresponding stages of cold-finishing reforming process.
The set-up procedure of blank mainly includes that 45 ° of turning Equal-channel Angular Pressing crystal grain refinements of rod iron obtain nanometer high intensity 20CrMoNi rod iron blank, carry out blanking the most successively, material softening annealing, bead blasted surfaces process technique, washing, phosphatization and soap Metallization processes;The pre-forging process of Warm Extrusion mainly includes that ejector pin of die set surface adds convex with the technique realizing material and being full of tooth cavity Platform, thus obtained the pre-forging that upper end is recessed, so can realize recessed portion shunting during Warm Extrusion finish-forging;Warm Extrusion finish-forging mistake Journey, material is while parts of tooth is filled, to recessed lumen loading.After profile of tooth filling, inner chamber is not yet full of or connects Near full, make material have free-pouring leeway during filling die cavity all the time, thus improve cavity filling, reduce and become Form drag and processing load;Precise cold finishing reforming process mainly includes that accurate clean shaping reaches required 20CrMoNi duplex The size and dimension precision of spur gear part and mechanical property.
Using this kind of scheme, the set-up procedure of blank, mould is obtained by channel pressings severe plastic deformations such as 45 ° of turnings High-strength accurate duplex-gear gear member accumulated deformation degree high, it is to utilize processing hardening in the course of processing, dynamic recovery, dynamic State recrystallization controls the microstructure of material, and crystal grain is effectively refined, and improves the purpose of blank mechanical property, duplicate gear Part mechanical property is good.
Use this kind of scheme, use Warm Extrusion cold-finishing combined precision manufacturing process, make whole technique blank heating temperature Degree is below recrystallization temperature, it is thus achieved that final accurate duplex-gear gear member surface smoothness high, non-scale, final size precision Height, shaping dies is long for service life simultaneously, stable working.
As a modification of the present invention, precise cold finishing reforming process uses floating cavity die method, the forging force of this process Less than closed die forging desirable pressure.
As a modification of the present invention, the feature of duplex spur gear blank preparation technology is the channel pressings such as 45 ° of turnings Severe plastic deformation mould uses recipient and the die of corner insert composition, and is arranged in shrink ring, wherein corner Between insert and die shoe, between pressure ram and upper bolster, it is designed with backing plate, carrys out dispersive pressure by arranging backing plate, play buffering Effect.
As a modification of the present invention, punch uses hollow arbor braid boss and band mandrel to fix two kinds of forms, shunts boss Being beneficial to molding, mandrel is more beneficial for the effect of the demoulding;
As a modification of the present invention, die work strip is reasonable in design, adds that cold-finishing shaping uses floating cavity die technology, more Product can be made to shape smoothly and to reach certain precision;
As a modification of the present invention, discharging device uses sleeve pushing and withstanding structure, i.e. has the effect from punch loading and unloading material, also can From die, eject product effect, axiality can also be increased simultaneously, improve part accuracy.
Using this kind of scheme, be conducive to improving the mold use life-span, becoming harmful friction is strong molding condition, final mould During tool Guan Bi, can obtain required by size, form accuracy and the mechanical property of 20CrMoNi duplex spur gear part.
Accompanying drawing illustrates:
It is presented herein below and in conjunction with the accompanying drawings and embodiments specific embodiments of the present invention is described in detail.
Fig. 1 is the machining sketch chart of tradition 20CrMoNi duplex spur gear;
Fig. 2 is nanometer high intensity rod iron blank severe plastic deformation mould of the present invention;
Fig. 3 is the Warm Extrusion blocking shaping dies of 20CrMoNi duplex spur gear of the present invention;
Fig. 4 is the Warm Extrusion finish-forging shaping dies of 20CrMoNi duplex spur gear of the present invention;
Fig. 5 is the cold-finishing shape mould of 20CrMoNi duplex spur gear of the present invention;
Being labeled as in above-mentioned figure:
Fig. 2 is 1. upper bolsters of nanometer high intensity rod iron blank severe plastic deformation mould, 2. recipient pressing plate, 3. adds for the first time Hot sheath, 4. pressure ram, 5. heater, 6. shrink ring, 7. recipient backing plate, 8. heating jacket, 9. die shoe, 10. in six Corner bolt, 11. hexagon socket head cap screws, 12. corner inserts, 13. guide pillars, 14. extruding pads, 15. recipients, 16. guide pin bushings, 17. squeeze Version fixed by depression bar, 18. hexagon socket head cap screws, 19. pressure ram backing plates.
Fig. 3 is 1. punch trip bolt, 2. upper bolsters of the Warm Extrusion blocking shaping dies of 20CrMoNi duplex spur gear, 3. convex mould pad, 4. punch pad, 5. trip bolt, 6. punch, 7. die pressing plate, 8. ground floor gland, 9. second layer gland, 10. material returned sleeve, 11. mandrels, 12. push rods, 13. cushion blocks, 14. mandrel fixed plates, 15. die shoes, 16. forging, 17. guide pillars, 18. trip bolts, 19. guide pin bushings, 20. pins, 21. rubber sheet gaskets.
Fig. 4 is 1. punch trip bolt, 2. upper bolsters of the Warm Extrusion finish-forging shaping dies of 20CrMoNi duplex spur gear, 3. convex mould pad, 4. punch pad, 5. trip bolt, 6. punch, 7. die pressing plate, 8. ground floor gland, 9. second layer gland, 10. material returned sleeve, 11. mandrels, 12. push rods, 13. mandrel fixed plates, 14. backing plates, 15. die shoes, 16. forging, 17. lead Post, 18. trip bolts, 19. guide pin bushings, 20. pins, 21. rubber sheet gaskets.
1. guide pin bushings of the cold-finishing shape mould of Fig. 5 20CrMoNi of the present invention duplex spur gear, 2. die, 3. floating template, 4. die block, 5. backing plate, 6. clamp nut, 7. die shoe, 8. trip bolt, 9. fix die, 10. spring base, 11. bullets Spring, 12. punch mandrels, 13. rubber sheet gaskets, 14. pre-collars, 15. trim rings, 16. punch, 17. pins, 18. hex screws, 19. Trip bolt, 20. upper bolsters, 21. guide pillars.
The invention has the beneficial effects as follows: due to the fact that and use the Warm Extrusion blocking with shunt method and finish-forging technique, Greatly reducing forging load, cold-finishing essence shaping mould increases floating cavity die device newly, makes die play positive rubbing action, Make friction that metal flow unfavorable factor is become favorable factor, so that metal is prone to be full of die cavity.Above-mentioned measure reduces forging Make load, improve die life, further promote the reality of the precision form new technology of 20CrMoNi duplex spur gear With change, decrease the time of Gear Processing, improve working (machining) efficiency, widen the processing model of automobile forging parts simultaneously Enclose.
Detailed description of the invention
The set-up procedure of Fig. 2 blank, obtains nanometer high intensity by 45 ° of turning Equal-channel Angular Pressing crystal grain refinements 20CrMoNi rod iron blank, carry out blanking the most successively, material softening annealing, bead blasted surfaces process technique, washing, phosphatization and make Metallization processes.
Fig. 3 is Warm Extrusion blocking shaping stage, and in the blocking stage, punch 6 uses the form of hollow arbor braid boss, on punch 6 Boss on forging 16, form cavity, be shunting boss, shunting boss is conducive to gear forming, mandrel 11 to be more beneficial for taking off The effect of mould.Blocking terminates when, under the effect of push rod 12, material returned sleeve 10 can not only eject forging 16, moreover it is possible to can increase Adding axiality, improve the precision of forging, now, most blocking profile of tooth die cavity fills with.
Fig. 4 is Warm Extrusion finish-forging shaping stage, and in this stage, the descending extruding of punch 6, the cavity formed due to blocking plays The effect of shunting metal, material is while parts of tooth is filled, to recessed lumen loading, it is achieved that material flowing shunting, Reduce extrusion load.At the end of finish-forging, under the effect of push rod 12, material returned sleeve 10 can not only eject forging 16, moreover it is possible to energy Increase axiality, improve the precision of forging.
Fig. 5 is the cold-finishing shape die drawing of 20CrMoNi duplex spur gear, and in this stage, in this stage, die is with upper mold Move down, so contribute to metal and flow downward, and bottom metal is faster than the metal flow at middle part, top, is metal It is prone to be full of die cavity, reduces forging load and improve die life simultaneously.Using floating cavity die technology, forging force is than traditional approach Forging force is little.At the end of cold-finishing, obtain size, form accuracy and mechanical property the most satisfactory high-strength accurate duplex Gear member.
Equipment needed thereby of the present invention is punching machine or hydraulic press.

Claims (4)

1., at a kind of high intensity 20CrMoNi duplex spur gear precise forming process and mould, it is characterized in that by 45 ° of turnings etc. Channel pressings severe plastic deformation technology obtains nanometer high intensity 20CrMoNi blank, becomes with Warm Extrusion cold-finishing combined precision Nanometer high intensity 20CrMoNi blank precision form is high-strength accurate duplex-gear gear member by shape method.
A kind of high intensity 20CrMoNi duplex spur gear precise forming process the most according to claim 1 and mould, it is special Levy be use Warm Extrusion cold-finishing combined precision manufacturing process, make whole technique blank heating temperature recrystallization temperature with Under, it is thus achieved that final accurate duplex-gear gear member surface smoothness high, non-scale, final size precision is high, shaping dies simultaneously Service life is long, stable working.
A kind of high intensity 20CrMoNi duplex spur gear precise forming process the most according to claim 1 and mould, it is special Levy the high-strength accurate duplex-gear gear member accumulated deformation degree being to be obtained by channel pressings severe plastic deformations such as 45 ° of turnings Height, crystal grain is effectively refined, and duplex-gear gear member mechanical property is good.
A kind of high intensity 20CrMoNi duplex spur gear precise forming process the most according to claim 1 and mould, duplex The feature of spur gear blank preparation technology is that the channel pressings severe plastic deformation moulds such as 45 ° of turnings use recipient and corner edge The die of block composition, and is arranged in shrink ring, wherein between corner insert and die shoe, between pressure ram and upper bolster It is designed with backing plate, carrys out dispersive pressure by arranging backing plate, play cushioning effect.
CN201610437058.1A 2016-06-20 2016-06-20 A kind of high intensity 20CrMoNi duplex spur gear precise forming process and mould Pending CN106077382A (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
CN107186158A (en) * 2017-06-09 2017-09-22 上海交通大学 Duplicate gear forging technology and mould based on plate bulk forming
CN110193582A (en) * 2019-06-19 2019-09-03 重庆巨泰机械有限公司 A kind of openable and closable floating die assembly
CN111659842A (en) * 2020-05-27 2020-09-15 四川工程职业技术学院 Die forging processing method for variable-section titanium alloy frame type forge piece
CN111872295A (en) * 2020-08-12 2020-11-03 苏州孚莱博精密金属科技有限公司 Cold heading module and cold heading process for manufacturing middle bolt of engine

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JP2004344931A (en) * 2003-05-22 2004-12-09 Honda Motor Co Ltd Method and apparatus for forming blank for forging
JP2006239770A (en) * 2005-03-07 2006-09-14 Daido Steel Co Ltd Die for forging
CN102151775A (en) * 2010-12-07 2011-08-17 重庆秋田齿轮有限责任公司 Blind hole gear blank precise forming method
CN103028630A (en) * 2012-12-14 2013-04-10 北京理工大学 Equal channel angular pressing structure with lateral turn angle of 45 degrees
CN103567340A (en) * 2013-11-26 2014-02-12 山东建筑大学 Novel precision forging technology of straight toothed spur gear for automobile and mold
CN103801650A (en) * 2012-11-07 2014-05-21 四川众友机械有限责任公司 Precision forging technology of tooth forms of duplex straight toothed spur gears

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2004344931A (en) * 2003-05-22 2004-12-09 Honda Motor Co Ltd Method and apparatus for forming blank for forging
JP2006239770A (en) * 2005-03-07 2006-09-14 Daido Steel Co Ltd Die for forging
CN102151775A (en) * 2010-12-07 2011-08-17 重庆秋田齿轮有限责任公司 Blind hole gear blank precise forming method
CN103801650A (en) * 2012-11-07 2014-05-21 四川众友机械有限责任公司 Precision forging technology of tooth forms of duplex straight toothed spur gears
CN103028630A (en) * 2012-12-14 2013-04-10 北京理工大学 Equal channel angular pressing structure with lateral turn angle of 45 degrees
CN103567340A (en) * 2013-11-26 2014-02-12 山东建筑大学 Novel precision forging technology of straight toothed spur gear for automobile and mold

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107186158A (en) * 2017-06-09 2017-09-22 上海交通大学 Duplicate gear forging technology and mould based on plate bulk forming
CN107186158B (en) * 2017-06-09 2019-02-01 上海交通大学 Duplicate gear forging technology and mold based on plate bulk forming
CN110193582A (en) * 2019-06-19 2019-09-03 重庆巨泰机械有限公司 A kind of openable and closable floating die assembly
CN111659842A (en) * 2020-05-27 2020-09-15 四川工程职业技术学院 Die forging processing method for variable-section titanium alloy frame type forge piece
CN111872295A (en) * 2020-08-12 2020-11-03 苏州孚莱博精密金属科技有限公司 Cold heading module and cold heading process for manufacturing middle bolt of engine
CN111872295B (en) * 2020-08-12 2021-03-26 苏州孚莱博精密金属科技有限公司 Cold heading module and cold heading process for manufacturing middle bolt of engine

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