CN104128767A - Gear production process beneficial to improving production efficiency and product quality - Google Patents
Gear production process beneficial to improving production efficiency and product quality Download PDFInfo
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- CN104128767A CN104128767A CN201410354462.3A CN201410354462A CN104128767A CN 104128767 A CN104128767 A CN 104128767A CN 201410354462 A CN201410354462 A CN 201410354462A CN 104128767 A CN104128767 A CN 104128767A
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- Prior art keywords
- gear
- blank
- product quality
- production efficiency
- conducive
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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
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
- B23P—METAL-WORKING NOT OTHERWISE PROVIDED FOR; COMBINED OPERATIONS; UNIVERSAL MACHINE TOOLS
- B23P15/00—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass
- B23P15/14—Making specific metal objects by operations not covered by a single other subclass or a group in this subclass gear parts, e.g. gear wheels
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B22—CASTING; POWDER METALLURGY
- B22D—CASTING OF METALS; CASTING OF OTHER SUBSTANCES BY THE SAME PROCESSES OR DEVICES
- B22D11/00—Continuous casting of metals, i.e. casting in indefinite lengths
- B22D11/10—Supplying or treating molten metal
- B22D11/11—Treating the molten metal
- B22D11/114—Treating the molten metal by using agitating or vibrating means
- B22D11/115—Treating the molten metal by using agitating or vibrating means by using magnetic fields
-
- 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
- C21D9/32—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for gear wheels, worm wheels, or the like
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23C—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; SURFACE TREATMENT OF METALLIC MATERIAL BY DIFFUSION INTO THE SURFACE, BY CHEMICAL CONVERSION OR SUBSTITUTION; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL
- C23C8/00—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals
- C23C8/06—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases
- C23C8/08—Solid state diffusion of only non-metal elements into metallic material surfaces; Chemical surface treatment of metallic material by reaction of the surface with a reactive gas, leaving reaction products of surface material in the coating, e.g. conversion coatings, passivation of metals using gases only one element being applied
- C23C8/20—Carburising
- C23C8/22—Carburising of ferrous surfaces
-
- C—CHEMISTRY; METALLURGY
- C23—COATING METALLIC MATERIAL; COATING MATERIAL WITH METALLIC MATERIAL; CHEMICAL SURFACE TREATMENT; DIFFUSION TREATMENT OF METALLIC MATERIAL; COATING BY VACUUM EVAPORATION, BY SPUTTERING, BY ION IMPLANTATION OR BY CHEMICAL VAPOUR DEPOSITION, IN GENERAL; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL
- C23F—NON-MECHANICAL REMOVAL OF METALLIC MATERIAL FROM SURFACE; INHIBITING CORROSION OF METALLIC MATERIAL OR INCRUSTATION IN GENERAL; MULTI-STEP PROCESSES FOR SURFACE TREATMENT OF METALLIC MATERIAL INVOLVING AT LEAST ONE PROCESS PROVIDED FOR IN CLASS C23 AND AT LEAST ONE PROCESS COVERED BY SUBCLASS C21D OR C22F OR CLASS C25
- C23F17/00—Multi-step processes for surface treatment of metallic material involving at least one process provided for in class C23 and at least one process covered by subclass C21D or C22F or class C25
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention discloses a gear production process beneficial to improving production efficiency and product quality. The gear production process includes the steps of blank casting, machine work, heat treatment, finishing cut and ground finish which are conducted in sequence. Raw materials for blank casting are 20 CrMnTiH. A crystallizer is adopted for electromagnetic stirring in the blank casting. Currents are 400 A and frequency is 2.5 Hz during electromagnetic stirring. The heat treatment includes the procedures that blanks obtained through machine work are heated to the temperature of 600-920 DEG C for carburizing treatment, and temperature of 600-920 DEG C is maintained for being not less than 3 hours during carburizing treatment; segmented heating is adopted as a heating mode and includes a first stage of preheating, a second stage of carburizing, a third stage of diffusing with a persistent period of 1-1.2 hours and a fourth stage of retarded cooling, the blanks are quenched after retarded cooling is carried out until the temperature of 500-600 DEG C is reached, the quenched blanks are heated to the temperature of 170-200 DEG C, heat preservation is conducted for being not less than 3 hours, and then tempering is carried out. The process is simple in procedure and short in time, and product compositions are even.
Description
Technical field
The present invention relates to the drive disk assembly manufacturing process for transmission of torque, particularly relate to a kind of Gear Production technique that is conducive to improve production efficiency and product quality.
Background technology
Gear is the critical component in plant equipment, and the quality of gear quality is directly connected to the service life of whole equipment.And the quality of gear quality depends on gear material and Technology for Heating Processing thereof to a great extent.Therefore, the producer relevant to gear manufacture all very payes attention to the research and development of gear material and heat treatment technics thereof both at home and abroad.
The material of prior art middle gear is selected the generally stressed and working environment in transmission system according to gear, and Technology for Heating Processing is that the corrosion resistance that guarantees gear surface thin hardened layer, gear surface and centre hardness, gear meets the means of technological requirement.The higher grade of product martensite metallographic that the heat treatment that is 20CrMnTiH gear for material in prior art obtains, in use very easily there is under external force work hardening in the gear obtaining like this, causing gear that superficial layer occurs within a short period of time departs from, have a strong impact on gear-driven stability and service life, although efficient by adopting the mode of strand to obtain gear blank, but C content difference is larger on tooth bar and the flank of tooth, affects gear life and further improve.
Summary of the invention
The higher grade of product martensite metallographic obtaining for the heat treatment that is 20CrMnTiH gear for material in above-mentioned prior art, in use very easily there is under external force work hardening in the gear obtaining like this, causing gear that superficial layer occurs within a short period of time departs from, have a strong impact on the problem in gear-driven stability and service life, the invention provides a kind of Gear Production technique that is conducive to improve production efficiency and product quality.
For the problems referred to above, a kind of Gear Production technique that is conducive to improve production efficiency and product quality provided by the invention reaches goal of the invention by following technical essential: a kind of Gear Production technique that is conducive to improve production efficiency and product quality, comprise strand in sequence, machining, heat treatment, essence cutting and grinding, the raw material of described strand is 20CrMnTiH, described strand adopts M-EMS, the electric current of described electromagnetic agitation is 400A, frequency is 2.5Hz, described heat treatment comprises that the blank that machining is obtained is heated to 600-920 ℃ and carries out Carburization Treatment, and in Carburization Treatment, above temperature hold-time is no less than 3h, the described heat stepwise that is heated to be, the 600-870 ℃ of preheating that the duration that is respectively the first stage is 20-30min, the 870-920 of the 1.5-2h of second stage ℃ carburizing, the 870-900 of phase III 1-1.2h ℃ diffusion, the slow cooling of fourth stage, blank slow cooling is quenched during to 500-600 ℃, blank after quenching is heated to 170-200 ℃ and insulation to be no less than 3h and to carry out tempering,
Described preheating is for being placed in blank methyl alcohol and propane gas heat altogether, described carburizing is that the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are heated up and be incubated, control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 1.1-1.15%, described being diffused as the blank of carburizing, methyl alcohol and propane gas environment temperature reduction insulation, the magnitude of recruitment of controlling methyl alcohol and propane gas, maintains carbon potential and remains 0.7-0.75%.
Further technical scheme is:
Between described machining and heat treatment, also comprise oil removing cleaning step.
The oil-removing cleaning agent that described oil removing cleaning step is 50-65 ℃ for employing temperature is no less than the immersion treatment of 30min to blank.
Between described heat treatment and essence cutting, also comprise the bead that is no less than 15min.
Described slow cooling is that stove is cold.
Described quenching is oil cooling, and oil temperature remains within the scope of 80-120 ℃.
Between described oil cooling and tempering step, also comprise cleaning step.
The present invention has following beneficial effect:
1, ring gauge manufacturing approach craft provided by the invention is simple, the 70-80% that heat treatment and carburizing time summation are prior art, the metallographic structure crystal grain of final gear product has obtained refinement simultaneously, gear product martensitic structure metallographic grade is 3, compared to prior art, adopt gear martensitic structure metallographic grade that this material obtains 2-3 the grade that declined, simultaneously, by above Technology for Heating Processing, the gear surface hardness obtaining remains on 59-60HRC, it is upper that centre hardness grade remains on 35-36HRC, and case-hardening layer thickness is 1.2-1.3mm.Above product gear parameter makes the in use difficult disengaging of cementation zone of gear, gear impact resistance, wearability and intensity suitable, and the 5-7 that be the gear that the existing Technology for Heating Processing of employing obtains on an equal basis the service life of gear doubly.
2, this process route adopts Carburization Treatment temperature parameter and each duration in stage, be convenient to realize the enough quenching degree of blank, little superheated susceptivity, good carburizing ability, the residual austenite content after heat treatment is few, carburizing and quenching deflection is little.
3, the M-EMS adopting in strand process, the alternating magnetic field that agitator excites is penetrated in the molten steel of strand, just induces therein electric current, and this induced-current and local magnetic field interaction produce electromagnetic force, act on molten steel volume element, thereby can promote molten steel motion.In the gear blank that the parameter of electromagnetic agitation is selected to make to obtain, the degree of segregation of Cr, Mn, C is respectively in 0.05,0.05 and 0.085 left and right, the electromagnetic agitation generally adopting compared to prior art, the degree of segregation drop-out value of Cr, Mn, C is respectively 0.035,0.02 and 0.035 left and right, be the selection of above technological parameter even the distribution of each component in gear blank, the uniformity that is conducive to mechanical property and wearability on the same working face of gear, is beneficial to life-span of gear.
The specific embodiment
Below in conjunction with embodiment, the present invention is described in further detail, but structure of the present invention is not limited only to following examples.
Embodiment 1:
A kind of Gear Production technique that is conducive to improve production efficiency and product quality, comprise strand in sequence, machining, heat treatment, essence cutting and grinding, the raw material of described strand is 20CrMnTiH, described strand adopts M-EMS, the electric current of described electromagnetic agitation is 400A, frequency is 2.5Hz, described heat treatment comprises that the blank that machining is obtained is heated to 600-920 ℃ and carries out Carburization Treatment, and in Carburization Treatment, above temperature hold-time is no less than 3h, the described heat stepwise that is heated to be, the 600-870 ℃ of preheating that the duration that is respectively the first stage is 20-30min, the 870-920 of the 1.5-2h of second stage ℃ carburizing, the 870-900 of phase III 1-1.2h ℃ diffusion, the slow cooling of fourth stage, blank slow cooling is quenched during to 500-600 ℃, blank after quenching is heated to 170-200 ℃ and insulation to be no less than 3h and to carry out tempering,
Described preheating is for being placed in blank methyl alcohol and propane gas heat altogether, described carburizing is that the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are heated up and be incubated, control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 1.1-1.15%, described being diffused as the blank of carburizing, methyl alcohol and propane gas environment temperature reduction insulation, the magnitude of recruitment of controlling methyl alcohol and propane gas, maintains carbon potential and remains 0.7-0.75%.
Ring gauge manufacturing approach craft provided by the invention is simple, the 70-80% that heat treatment and carburizing time summation are prior art, the metallographic structure crystal grain of final gear product has obtained refinement simultaneously, gear product martensitic structure metallographic grade is 3, compared to prior art, adopt gear martensitic structure metallographic grade that this material obtains 2-3 the grade that declined, simultaneously, by above Technology for Heating Processing, the gear surface hardness obtaining remains on 59-60HRC, it is upper that centre hardness grade remains on 35-36HRC, and case-hardening layer thickness is 1.2-1.3mm.Above product gear parameter makes the in use difficult disengaging of cementation zone of gear, gear impact resistance, wearability and intensity suitable, and the 5-7 that be the gear that the existing Technology for Heating Processing of employing obtains on an equal basis the service life of gear doubly.
The Carburization Treatment temperature parameter that this process route adopts and each duration in stage, be convenient to realize the enough quenching degree of blank, little superheated susceptivity, good carburizing ability, the residual austenite content after heat treatment is few, carburizing and quenching deflection is little.
The M-EMS adopting in strand process, the alternating magnetic field that agitator excites is penetrated in the molten steel of strand, just induces therein electric current, and this induced-current and local magnetic field interaction produce electromagnetic force, act on molten steel volume element, thereby can promote molten steel motion.In the gear blank that the parameter of electromagnetic agitation is selected to make to obtain, the degree of segregation of Cr, Mn, C is respectively in 0.05,0.05 and 0.085 left and right, the electromagnetic agitation generally adopting compared to prior art, the degree of segregation drop-out value of Cr, Mn, C is respectively 0.035,0.02 and 0.035 left and right, be the selection of above technological parameter even the distribution of each component in gear blank, the uniformity that is conducive to mechanical property and wearability on the same working face of gear, is beneficial to life-span of gear.
Embodiment 2:
The present embodiment is further qualified on the basis of embodiment 1, for the oil pollution that in process route between elimination machining, plant equipment or environment cause blank, avoid greasy dirt to affect thermal effectiveness, between described machining and heat treatment, also comprise oil removing cleaning step.
For obtaining good oil removing cleaning performance and cleaning efficiency, the oil-removing cleaning agent that described oil removing cleaning step is 50-65 ℃ for employing temperature is no less than the immersion treatment of 30min to blank.
For further strengthening the surface quality of product, between described heat treatment and essence cutting, also comprise the bead that is no less than 15min.
For preventing that in cooling procedure, oxidizing gas etc. impacts the surface of blank, described slow cooling is that stove is cold.Further, described quenching is oil cooling, and oil temperature remains within the scope of 80-120 ℃.
For avoiding tempering effect to be subject to the impact of other factors, between described oil cooling and tempering step, also comprise cleaning step.
Above content is the further description of the present invention being done in conjunction with concrete preferred embodiment, can not assert that the specific embodiment of the present invention is confined to these explanations.For general technical staff of the technical field of the invention, not departing from other embodiments that draw under technical scheme of the present invention, all should be included in protection scope of the present invention.
Claims (7)
1. a Gear Production technique that is conducive to improve production efficiency and product quality, comprise strand in sequence, machining, heat treatment, essence cutting and grinding, it is characterized in that, the raw material of described strand is 20CrMnTiH, described strand adopts M-EMS, the electric current of described electromagnetic agitation is 400A, frequency is 2.5Hz, described heat treatment comprises that the blank that machining is obtained is heated to 600-920 ℃ and carries out Carburization Treatment, and in Carburization Treatment, above temperature hold-time is no less than 3h, the described heat stepwise that is heated to be, the 600-870 ℃ of preheating that the duration that is respectively the first stage is 20-30min, the 870-920 of the 1.5-2h of second stage ℃ carburizing, the 870-900 of phase III 1-1.2h ℃ diffusion, the slow cooling of fourth stage, blank slow cooling is quenched during to 500-600 ℃, blank after quenching is heated to 170-200 ℃ and insulation to be no less than 3h and to carry out tempering,
Described preheating is for being placed in blank methyl alcohol and propane gas heat altogether, described carburizing is that the blank of above-mentioned warm-up phase, methyl alcohol and propane gas environment are heated up and be incubated, control the magnitude of recruitment of methyl alcohol and propane gas, maintain carbon potential and remain 1.1-1.15%, described being diffused as the blank of carburizing, methyl alcohol and propane gas environment temperature reduction insulation, the magnitude of recruitment of controlling methyl alcohol and propane gas, maintains carbon potential and remains 0.7-0.75%.
2. a kind of Gear Production technique that is conducive to improve production efficiency and product quality according to claim 1, is characterized in that, also comprises oil removing cleaning step between described machining and heat treatment.
3. a kind of Gear Production technique that is conducive to improve production efficiency and product quality according to claim 2, is characterized in that, the oil-removing cleaning agent that described oil removing cleaning step is 50-65 ℃ for employing temperature is no less than the immersion treatment of 30min to blank.
4. a kind of Gear Production technique that is conducive to improve production efficiency and product quality according to claim 1, is characterized in that, between described heat treatment and essence cutting, also comprises the bead that is no less than 15min.
5. a kind of Gear Production technique that is conducive to improve production efficiency and product quality according to claim 1, is characterized in that, described slow cooling is that stove is cold.
6. a kind of Gear Production technique that is conducive to improve production efficiency and product quality according to claim 1, is characterized in that, described quenching is oil cooling, and oil temperature remains within the scope of 80-120 ℃.
7. a kind of Gear Production technique that is conducive to improve production efficiency and product quality according to claim 6, is characterized in that, also comprises cleaning step between described oil cooling and tempering step.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410354462.3A CN104128767A (en) | 2014-07-24 | 2014-07-24 | Gear production process beneficial to improving production efficiency and product quality |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201410354462.3A CN104128767A (en) | 2014-07-24 | 2014-07-24 | Gear production process beneficial to improving production efficiency and product quality |
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| CN104128767A true CN104128767A (en) | 2014-11-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201410354462.3A Pending CN104128767A (en) | 2014-07-24 | 2014-07-24 | Gear production process beneficial to improving production efficiency and product quality |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109609893A (en) * | 2019-01-22 | 2019-04-12 | 北京机电研究所有限公司 | A kind of method of thinning microstructure after vacuum carburization |
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|---|---|---|---|---|
| US4761867A (en) * | 1987-02-12 | 1988-08-09 | Eaton Corporation | Method for producing ring gears for heavy-duty drive axles |
| CN1517174A (en) * | 2003-01-17 | 2004-08-04 | 谢智庆 | Manufucturing method of notch wheel having 90-180 teeth and notch wheel made by gaid method |
| CN102501035A (en) * | 2011-10-12 | 2012-06-20 | 南京金鑫传动设备有限公司 | Quenching and tempering method in tooth punching process of gear with medium-hard tooth surface |
| CN102699643A (en) * | 2012-06-01 | 2012-10-03 | 上海格尔汽车附件有限公司 | Processing method for pinion of automobile steering device |
| CN102776470A (en) * | 2012-07-09 | 2012-11-14 | 陈曦 | Surface chemico-thermal treatment method for mechanical parts and equipment used thereby |
| CN103273285A (en) * | 2013-05-29 | 2013-09-04 | 宁波东湖液压传动有限公司 | Method for machining inner gear ring |
| CN103286533A (en) * | 2013-05-28 | 2013-09-11 | 重庆市首业机械制造有限公司 | Processing technology for rear axle drive bevel gear |
-
2014
- 2014-07-24 CN CN201410354462.3A patent/CN104128767A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US4761867A (en) * | 1987-02-12 | 1988-08-09 | Eaton Corporation | Method for producing ring gears for heavy-duty drive axles |
| CN1517174A (en) * | 2003-01-17 | 2004-08-04 | 谢智庆 | Manufucturing method of notch wheel having 90-180 teeth and notch wheel made by gaid method |
| CN102501035A (en) * | 2011-10-12 | 2012-06-20 | 南京金鑫传动设备有限公司 | Quenching and tempering method in tooth punching process of gear with medium-hard tooth surface |
| CN102699643A (en) * | 2012-06-01 | 2012-10-03 | 上海格尔汽车附件有限公司 | Processing method for pinion of automobile steering device |
| CN102776470A (en) * | 2012-07-09 | 2012-11-14 | 陈曦 | Surface chemico-thermal treatment method for mechanical parts and equipment used thereby |
| CN103286533A (en) * | 2013-05-28 | 2013-09-11 | 重庆市首业机械制造有限公司 | Processing technology for rear axle drive bevel gear |
| CN103273285A (en) * | 2013-05-29 | 2013-09-04 | 宁波东湖液压传动有限公司 | Method for machining inner gear ring |
Non-Patent Citations (1)
| Title |
|---|
| 许伟阳: "连铸齿轮钢矩形坯碳"锭型"偏析的形成与控制", 《中国优秀硕士学位论文全文数据库工程科技Ⅰ辑》 * |
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109609893A (en) * | 2019-01-22 | 2019-04-12 | 北京机电研究所有限公司 | A kind of method of thinning microstructure after vacuum carburization |
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