CN114107647A - Heat treatment process for 50CrVA automobile plate spring - Google Patents
Heat treatment process for 50CrVA automobile plate spring Download PDFInfo
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- CN114107647A CN114107647A CN202111252160.1A CN202111252160A CN114107647A CN 114107647 A CN114107647 A CN 114107647A CN 202111252160 A CN202111252160 A CN 202111252160A CN 114107647 A CN114107647 A CN 114107647A
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- 238000000034 method Methods 0.000 title claims abstract description 26
- 238000010438 heat treatment Methods 0.000 title claims abstract description 21
- 238000010791 quenching Methods 0.000 claims abstract description 71
- 230000000171 quenching effect Effects 0.000 claims abstract description 71
- 238000005496 tempering Methods 0.000 claims abstract description 51
- 238000004080 punching Methods 0.000 claims abstract description 18
- 238000003825 pressing Methods 0.000 claims abstract description 13
- 235000014676 Phragmites communis Nutrition 0.000 claims abstract description 11
- 238000001816 cooling Methods 0.000 claims abstract description 9
- 244000089486 Phragmites australis subsp australis Species 0.000 claims abstract 2
- 238000005422 blasting Methods 0.000 claims description 8
- 239000000463 material Substances 0.000 claims description 2
- 244000273256 Phragmites communis Species 0.000 description 7
- 229910000831 Steel Inorganic materials 0.000 description 6
- 239000010959 steel Substances 0.000 description 6
- 238000004519 manufacturing process Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 239000000725 suspension Substances 0.000 description 2
- 238000012360 testing method Methods 0.000 description 2
- 239000000956 alloy Substances 0.000 description 1
- 229910045601 alloy Inorganic materials 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 238000001125 extrusion Methods 0.000 description 1
- 238000011056 performance test Methods 0.000 description 1
- 238000012545 processing Methods 0.000 description 1
- 230000002035 prolonged effect Effects 0.000 description 1
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- 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
- C21D9/02—Heat treatment, e.g. annealing, hardening, quenching or tempering, adapted for particular articles; Furnaces therefor for springs
-
- C—CHEMISTRY; METALLURGY
- C21—METALLURGY OF IRON
- C21D—MODIFYING THE PHYSICAL STRUCTURE OF FERROUS METALS; GENERAL DEVICES FOR HEAT TREATMENT OF FERROUS OR NON-FERROUS METALS OR ALLOYS; MAKING METAL MALLEABLE, e.g. BY DECARBURISATION OR TEMPERING
- C21D1/00—General methods or devices for heat treatment, e.g. annealing, hardening, quenching or tempering
- C21D1/18—Hardening; Quenching with or without subsequent tempering
-
- 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
- C21D11/00—Process control or regulation for heat treatments
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- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Physics & Mathematics (AREA)
- Thermal Sciences (AREA)
- Crystallography & Structural Chemistry (AREA)
- Mechanical Engineering (AREA)
- Materials Engineering (AREA)
- Metallurgy (AREA)
- Organic Chemistry (AREA)
- Heat Treatment Of Articles (AREA)
Abstract
The invention discloses a heat treatment process for a 50CrVA automobile plate spring, which solves the problems of low hardness and short fatigue life of the existing automobile plate spring, and sets the quenching temperature in a quenching furnace to be 950-990 ℃ and the tempering temperature in a tempering furnace to be 430-450 ℃; after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, conveying the prepared plate spring piece into the quenching furnace; then, taking out the plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole; the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming; the plate spring after the arc height forming is placed into a quenching tank for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through a mechanical arm at an outlet of the quenching tank and placed into a tempering furnace; and moving the reeds in a tempering furnace through a conveying chain, and finally putting finished products in order to reasonably classify.
Description
Technical Field
The invention relates to the technical field of plate spring production, in particular to the technical field of heat treatment process of a 50CrVA automobile plate spring.
Background
The steel plate spring is an elastic element which is most widely applied in automobile suspensions, and is an elastic beam which is approximately equal in strength and formed by combining a plurality of alloy spring pieces which are equal in width but unequal in length (the thicknesses can be equal or unequal). The automobile steel plate spring connects the frame and the axle together in a suspension mode, is exposed between the frame and the axle, bears the load impact of wheels on the frame, reduces the violent vibration of the automobile body, and keeps the running stability of the automobile and the adaptability to different road conditions. The steel plate spring forms extension movement when bearing load impact, strong friction is generated between the steel plates, namely, an extrusion and stretching phenomenon is generated, two friction surfaces generate two movement friction forces in different directions, the temperature rise of the steel plate spring is caused, surface strain occurs, fine cracks are shown, when the load impact frequency is increased, the friction movement force generated by the extension movement is also increased, and when the stress concentration point reaches the fatigue limit, single plates or whole stacks are broken.
In the process of processing the steel plate spring, after the reed is cut to a fixed length according to needs, the reed is heated to a specified temperature in a heating furnace, is bent and shaped in the temperature range, and then enters a quenching bath for quenching. Wherein the quenching temperature and the tempering temperature are key factors influencing the product quality.
The existing production process generally has the problems of low plate spring hardness, early plate spring breakage and short fatigue life.
Disclosure of Invention
The invention aims to solve the problems of low hardness and short fatigue life of the conventional automobile plate spring, and provides a heat treatment process for a 50CrVA automobile plate spring.
The invention specifically adopts the following technical scheme for realizing the purpose:
a heat treatment process for a 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to be 950-990 ℃, and setting the tempering temperature in the tempering furnace to be 430-450 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Further, the quenching temperature was set to 960 ℃.
Further, the tempering temperature is set to 440 ℃.
Further, the feeding mechanism is a swing type feeding machine.
Further, the step time of the swing type feeder is 17 seconds, and the swing time is 130 seconds; the material thickness was 16 mm.
Further, the long-pressure temperature of the arc press is 930-.
Further, the long-pressing temperature of the arc pressing machine is 950 ℃.
The invention has the following beneficial effects:
(1) according to the method, the quenching temperature in the quenching furnace is set to 950-990 ℃, the tempering temperature in the tempering furnace is set to 430-450 ℃, and experiments prove that the hardness of the automobile plate spring is improved, the automobile plate spring is prevented from being broken in advance, and the service life of the automobile plate spring is prolonged;
(2) the operation flow of the plate spring heat treatment process is simple, the process conditions are easy to control, and the quality of the produced product is high;
(3) the process temperature limited in the application also realizes the effect of saving gas energy, and reduces the production cost of manufacturers.
Drawings
FIG. 1 is a metallographic structure of the product of example 1;
FIG. 2 is a metallographic structure of the product of example 2;
FIG. 3 is a metallographic structure of the product of example 3;
FIG. 4 is a metallographic structure of the product of example 4;
FIG. 5 is a metallographic structure representation of the product of example 5;
FIG. 6 is a metallographic structure chart of the product of example 6.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some, but not all, embodiments of the present invention. The components of embodiments of the present invention generally described and illustrated in the figures herein may be arranged and designed in a wide variety of different configurations.
Thus, the following detailed description of the embodiments of the present invention, presented in the figures, is not intended to limit the scope of the invention, as claimed, but is merely representative of selected embodiments of the invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
Example 1
Referring to fig. 1, the heat treatment process of the 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to be 950 ℃ and the tempering temperature in the tempering furnace to be 440 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Example 2
Referring to fig. 2, the heat treatment process of the 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to 960 ℃, and setting the tempering temperature in the tempering furnace to 440 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Example 3
Referring to fig. 3, the heat treatment process of the 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to 990 ℃ and the tempering temperature in the tempering furnace to 440 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Example 4
Referring to fig. 4, the heat treatment process of the 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to 960 ℃, and setting the tempering temperature in the tempering furnace to 430 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Example 5
Referring to fig. 5, the heat treatment process of the 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to 960 ℃, and setting the tempering temperature in the tempering furnace to 440 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Example 6
Referring to fig. 6, the heat treatment process of the 50CrVA automobile plate spring specifically comprises the following steps:
step 1: setting the quenching temperature in the quenching furnace to 960 ℃, and setting the tempering temperature in the tempering furnace to 450 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, and finally putting the finished products in order, reasonably classifying and performing shot blasting treatment.
Test detection
The workshop tape sheets prepared by the processes of examples 1 to 6 were respectively subjected to performance tests, and the test data are shown in the following table.
According to the detection results, the process temperatures in the quenching furnace and the tempering furnace defined in the application enable the metallographic structure of the prepared product to be finer, the depth of the decarburized layer is lower, the performance of the product is improved, and the effect of prolonging the service life of the plate spring is achieved.
Claims (7)
1. A heat treatment process for a 50CrVA automobile plate spring is characterized by comprising the following steps:
step 1: setting the quenching temperature in the quenching furnace to be 950-990 ℃, and setting the tempering temperature in the tempering furnace to be 430-450 ℃;
step 2: after the temperature in the quenching furnace and the tempering furnace reaches a set temperature value, starting a feeding mechanism, and conveying the prepared plate spring piece into the quenching furnace;
and step 3: taking out the quenched plate spring from the furnace by using a manipulator, moving the plate spring to a thermal straightening and punching integrated machine, thermally straightening the plate spring, and punching a central hole;
and 4, step 4: the mechanical arm moves the straightened and punched plate spring to an arc pressing machine for arc height forming;
and 5: the plate spring after the arc height forming is placed into a quenching tank through a mechanical arm for quenching and cooling, the plate spring is transferred through a lifting mechanism and a conveying chain, and the plate spring is taken away through the mechanical arm at an outlet of the quenching tank and placed into a tempering furnace;
step 6: and moving the reeds through a conveying chain in a tempering furnace, putting finished products in order, reasonably classifying, and performing shot blasting treatment.
2. The heat treatment process of claim 1, wherein the quenching temperature is set to 960 ℃.
3. The heat treatment process of the 50CrVA automobile leaf spring as claimed in claim 1, wherein the tempering temperature is set to 440 ℃.
4. The heat treatment process of the 50CrVA automobile leaf spring as claimed in claim 1, wherein the feeding mechanism is a swing type feeding machine.
5. The heat treatment process of the 50CrVA automobile plate spring as claimed in claim 4, wherein the step time of the swing type feeder is 17 seconds, and the swing time is 130 seconds; the material thickness was 16 mm.
6. The heat treatment process for the 50CrVA automobile plate spring as claimed in claim 1, wherein the long-pressing temperature of the arc press is 930-970 ℃.
7. The heat treatment process of the 50CrVA automobile plate spring as claimed in claim 6, wherein the long pressing temperature of the arc press is 950 ℃.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111252160.1A CN114107647A (en) | 2021-10-27 | 2021-10-27 | Heat treatment process for 50CrVA automobile plate spring |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111252160.1A CN114107647A (en) | 2021-10-27 | 2021-10-27 | Heat treatment process for 50CrVA automobile plate spring |
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| Publication Number | Publication Date |
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| CN114107647A true CN114107647A (en) | 2022-03-01 |
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| CN202111252160.1A Pending CN114107647A (en) | 2021-10-27 | 2021-10-27 | Heat treatment process for 50CrVA automobile plate spring |
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Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006071082A (en) * | 2004-09-06 | 2006-03-16 | Horikiri:Kk | Plate spring and its manufacturing method |
| CN103014533A (en) * | 2011-10-19 | 2013-04-03 | 宝钢集团新疆八一钢铁有限公司 | Technique for prolonging fatigue life of 50CrVA plate spring |
| CN105643201A (en) * | 2014-12-03 | 2016-06-08 | 重庆业高家具有限公司 | 50CrVA leaf spring machining technology |
| CN105734243A (en) * | 2014-12-09 | 2016-07-06 | 重庆凌云工具有限公司 | Quenching process for automobile leaf spring |
| CN109136513A (en) * | 2018-10-12 | 2019-01-04 | 四川宏术汽车钢板弹簧有限公司 | A kind of automobile leaf spring production technology |
| CN109694950A (en) * | 2019-02-27 | 2019-04-30 | 淄博高新区百力工贸有限公司 | The automatic quenching line of leaf spring |
| CN209555315U (en) * | 2019-02-27 | 2019-10-29 | 淄博高新区百力工贸有限公司 | The automatic quenching line of leaf spring |
-
2021
- 2021-10-27 CN CN202111252160.1A patent/CN114107647A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2006071082A (en) * | 2004-09-06 | 2006-03-16 | Horikiri:Kk | Plate spring and its manufacturing method |
| CN103014533A (en) * | 2011-10-19 | 2013-04-03 | 宝钢集团新疆八一钢铁有限公司 | Technique for prolonging fatigue life of 50CrVA plate spring |
| CN105643201A (en) * | 2014-12-03 | 2016-06-08 | 重庆业高家具有限公司 | 50CrVA leaf spring machining technology |
| CN105734243A (en) * | 2014-12-09 | 2016-07-06 | 重庆凌云工具有限公司 | Quenching process for automobile leaf spring |
| CN109136513A (en) * | 2018-10-12 | 2019-01-04 | 四川宏术汽车钢板弹簧有限公司 | A kind of automobile leaf spring production technology |
| CN109694950A (en) * | 2019-02-27 | 2019-04-30 | 淄博高新区百力工贸有限公司 | The automatic quenching line of leaf spring |
| CN209555315U (en) * | 2019-02-27 | 2019-10-29 | 淄博高新区百力工贸有限公司 | The automatic quenching line of leaf spring |
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Application publication date: 20220301 |