CN102501009B - Processing technology of arc-shaped spring - Google Patents
Processing technology of arc-shaped spring Download PDFInfo
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- CN102501009B CN102501009B CN201110330177.4A CN201110330177A CN102501009B CN 102501009 B CN102501009 B CN 102501009B CN 201110330177 A CN201110330177 A CN 201110330177A CN 102501009 B CN102501009 B CN 102501009B
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Abstract
The invention relates to a processing technology of a large-radian arc-shaped spring. The processing technology is characterized by comprising the following procedures of: spring coiling: primary stress relief annealing; spring grinding; spring bending into an arc-shaped spring; secondary stress relief annealing; shot blasting; hot-strong pressing; sorting; angular rigidity and torque test; fatigue life test; and surface antirust treatment. According to the forming technology of the arc-shaped spring provided by the invention, the arc-shaped spring with the free angle of being more than 45 degrees can be effectively formed, the thermal relaxation rate of the spring is less than 2%, the instantaneous torque is large, the fatigue life is 1 million times, and the technical problems of low finished product rate and incapability for normal use of the large-radian arc-shaped spring in the prior art are solved.
Description
Technical field
The present invention relates to a kind of manufacture craft of spring, particularly relate to a kind of processing technology of arc spring of large radian.
Background technology
Spring is as the widely used flexible member of one, its profile mostly is cylindrical, production and processing can be divided into cold coiling to be shaped and hot rolling is shaped, and the main manufacturing procedure that wherein cold coiling is shaped has wind spring → stress relief annealing → end face to polish → (chamfering) → ball blast → process → surface treatment → packaging etc. of halting.
Spring in order to coincide better with its assembly space, also have and is designed to non-cylindrical, as the spring of automobile dual-mass flywheel.The processing technology of this spring is not exclusively the same with the processing technology of helical spring.
Such as on December 26th, 2007 has announced the Chinese patent of No. CN101092014A, name is called a kind of manufacture craft and special equipment thereof of arched spring in use for hydraulic torque converter of car, and the making step of arc spring is: materials procurement → roll into arc → destressing tempering → shot peening → process → cross grinding of halting → outer rounded corner → dimensional gaughing → performance checking → fatigue life inspection → surperficial antirust treatment → finished product packing.Described step is halted to process and is adopted Special arc spring compressive setting machine, on its base, side is provided with bearing block, bearing block pin Bonding pressure bar, and the press rods other end presses cylinder by depression bar connector, press rods is provided with spiral pressure head, and base is provided with lower spiral pressure head.
Announced the Chinese patent of CN101786221A on July 28th, 2010 for another example, name is called the processing method of arc spring, and the making step of arc spring is:
1.1 buying, check and choose suitable raw material;
1.2 pairs of raw material screw types chosen bend cold coiling camber, enclose to the outer end circle of spring and tightly process with adjacent second;
Spring after 1.3 pairs of cold coilings is annealed;
To the grinding of both ends of the spring face after 1.4 annealing, polish the end circle of spring;
1.5 then carry out shot peening to spring;
1.6 pairs of springs through bead carry out degaussing process;
Carry out cleaning after 1.7 spring degaussings and enter hot prestressing operation;
Carry out load sorting by different load dividings after 1.8 hot prestressing, what performance was consistent is one group;
1.9 finally do surperficial antirust treatment to spring makes final products arc spring, and packaging warehouse-in.
In above-mentioned two kinds of arc spring processing process, all in the single shaft synchronization control function of this procedure of wind spring by Digital Control Plane Roll-up Spring, constantly change the pitch of turn, make outer pitch be greater than the pitch of another side, thus make the spring rolled out be arc.There is following drawback in this technique:
Roll formed arc, its axial line is in a plane, and after destressing tempering process, due to the change of spring diameter, whole piece spring axis line can be caused to become a spirality, and namely spring is not in a plane, cannot normally use.
Free angle is greater than to the arc spring of 45 degree, if rolled into arc in wind spring operation, spring can around wind spring mandrel fast rotational, under the effect of the centre of force, spring outer diameter, pitch equidimension all can change, and cannot make qualified arc spring.
Summary of the invention
The invention provides a kind of can effective shaping free angle arc spring of being greater than 45 degree, and ensure that the hot wire-CVD rate of spring is less than 2%, instantaneous torque is large, fatigue life the arc spring of more than 1,000,000 times moulding process; The yield rate solving the arc spring of the wide-angle existed in prior art is low, the technical problem that can not normally use.
Above-mentioned technical problem of the present invention is solved by following technical proposals: a kind of processing technology of arc spring, is characterized in that: comprise following operation:
The first step, wind spring, by steel wire stock according to prefabricated height, external diameter and the number of turns, the two ends of spring are also tight, be wound into columniform helical spring;
Second step, for the first time stress relief annealing;
3rd step, mill spring;
4th step, to the spring after tempering each circle carry out one by one open distance, make the pitch of spring side be greater than the pitch of opposite side, linear springs become arc spring;
5th step, second time stress relief annealing;
6th step, ball blast, adopts twice ball blast, first time the diameter of ball blast and intensity be greater than diameter and the intensity of the second ball blast;
7th step, hot prestressing;
8th step, sorting;
9th step, angular rigidity and torsion-testing,
Tenth step, fatigue life test;
11 step, surperficial antirust treatment.
During first step wind spring, material rolling through numerical-control spring coiling machine, forming a shape is columniform helical spring, external diameter, the pitch of its coil are equal, two ends respectively have 1 circle-3.5 circle to be and tight that the computer numerical control spring coiling machine of wind spring more than four axles carries out, and the external diameter control accuracy of spring coiling machine should be less than 0.2mm, the number of turns controls to be less than 0.1 circle, and spring free length control accuracy is less than 0.5mm.Arc do not carry out to spring when wind spring shaping, but first adopt mesh-belt type hot air circulation annealing stove to carry out a temper, to eliminate in coiling process the harmful residual tension remained in spring material to columniform spring after wind spring.Then adopt spring grinder to be polished in the work support face at the two ends of spring, spring end face angle of grinding surface is at 270 ° ~ 340 °, and termination residual thickness is greater than 10% of steel wire diameter.Have passed through tempering eliminate harmful residual tension and mill spring after, carry out camber line more shaping, distance is carried out out in columned spring side, form arc spring, arc spring natural torsion after shaping becomes an arc, inner side and outside steel wire between spacing unevenness be less than 0.5mm, spring plane degree is less than 2mm, and spring tip original position is all consistent.After formation arc, again carry out temper, ensure that arc spring after shaping can not resilience, meet the shaping needs of wide-angle arc spring.The present invention is shaped by wind spring-annealing-mill spring-camber line-is annealed, such twice annealing, wind spring and camber line shaping technique separately complete the machine-shaping of the spring of wide-angle, the axis of the arc spring of shaping wide-angle is positioned on same camber line, and spring is not easy distortion, hot wire-CVD rate is low, and yield rate is high.Avoid arc external diameter, the pitch variation of while wind spring, in original processing technology, just having carried out the shaping generation of arc large, the very difficult problem of state modulator, in original technique, while wind spring, camber line is shaping, because camber ratio is larger, make the part spooled make circumference along wind spring mandrel to rotate, cause size unstable.And method of the present invention is by wind spring and camber line is shaping separately carries out, and effectively avoids this problem.Carry out tempering after shaping arc spring while it also avoid wind spring, spring axis line, not on a camber line, makes the molding effect of spring bad simultaneously, and the problem offset does not occur spring in a plane.After wind spring of the present invention, tempering is once, after camber line is shaping again tempering once, make shaping after spring camber line angle keep.
As preferably, raw material are selected before wind spring, raw-material case hardness is greater than 51HRC, the raw-material contraction percentage of area is greater than 35%, without the non-metallic inclusion more than 15 microns in raw-material section radius 1/3 scope, the injurous defect of raw material surface more than 40 microns answers spray paint as remarkable mark.In the work of automobile dual-mass flywheel arc spring, the deep-slotted chip breaker of spring and flywheel has very large frictional resistance, therefore require that the raw material of spring have higher tensile strength, case hardness and higher toughness properties, strict control has been carried out to the non-metallic inclusion in material simultaneously.The sign of spraying paint can be identified in wind spring process, thus is eliminated.
As preferably, after described wind spring first time stress relief annealing temperature at 320 DEG C ~ 470 DEG C, annealing time is at 30-65 minute, and effective temperature retention time of tempering furnace is greater than 40% of the spring turnover stove time.Through first time, the residual stress on tempered spring surface is less than 150Mpa, eliminates the harmful stress in the spring after wind spring, improves the service life of spring.
As preferably, the temperature of described second time stress relief annealing is at 200 DEG C ~ 450 DEG C, and annealing time was at 20 ~ 60 minutes, and effective temperature retention time of tempering furnace is greater than 40% of the spring turnover stove time.After camber line is shaping, carry out second time tempering, the residual stress of spring surface is less than 250Mpa, ensures the molding effect of the spring that camber line is shaping.
As preferably, described ball blast adopts Caterpillar type shot blasting machine to carry out ball blast, and the impelling material of ball blast is steel wire cut pill, the hardness of steel wire cut pill is greater than 600HV, impelling shot linear velocity is not less than 60m/s, and the diameter of ball blast is 0.4 ~ 0.8mm for the first time, and the diameter of second time ball blast is 0.2 ~ 0.6mm.During twice ball blast, the frequency of jettisoninging of shot-blasting machine is not less than 50Hz, after first time ball blast, spring surfaces externally and internally and coverage rate are not less than 95%, ball blast intensity is not less than 0.3A, and the residual compressive stress on surface is not less than-500Mpa, and subsurface maximum residual stress is not less than-700Mpa.After second time ball blast, spring surfaces externally and internally and coverage rate are not less than 100%, and ball blast intensity is not less than 0.2A, and the residual compressive stress on surface is not less than-600Mpa, and subsurface maximum residual stress is not less than-800Mpa.
As preferably, described hot prestressing temperature is set as 180 DEG C ~ 280 DEG C, temperature retention time was at 10 ~ 30 minutes, pressure setting is spring theory pressure and 1.2 ~ 2 times of moment of torsion, suppressing in process, the actual temperature of spring is not less than 50 DEG C, and spring is depressed into and tight rear stop 0.5 ~ 15s by power press, and suppressing number of times is 1 ~ 5 time.After hot prestressing, prevent relaxing of spring, improve the fatigue strength of spring.
As preferably, described sorting comprises radius of curvature sorting, angular sorting and perpendicularity sorting.By the inspection machine free angle of measuring spring and perpendicularity accurately, the arc radius of detection springs simultaneously, selects qualified products.
As preferably, the radian of the spring after arc wind spring is greater than π/4.The good forming effect of the spring of wide-angle, yield rate is high.
Therefore, the processing technology of arc spring of the present invention possesses following advantage: the ratio of briquetting for the arc spring of wide-angle is high, and the central axis of spring is positioned on same camber line, and arc can not produce skew, and the parameter of spring easily controls, and fatigue life is long.
Detailed description of the invention
Below by embodiment, the technical scheme of invention is described in further detail.
Embodiment:
A processing technology for arc spring, selects OTEVA 75SC material as the raw material of processing, checks that substandard product eliminated by raw material, carries out wind spring.The computer numerical control spring coiling machine of wind spring more than four axles carries out, and steel wire stock is according to prefabricated height, external diameter and the number of turns, and the two ends of spring are also tight, is wound into columniform helical spring.In tempering furnace, keep annealing temperature to be stress relief annealing under the condition of 410 DEG C after wind spring, temperature retention time is 60 minutes, and the residual stress of spring surface is less than 150Mpa.After annealing, grinding is carried out to the both ends of the surface of spring, grinding angle is at 270 ~ 330 degree, it is steel wire diameter that termination residual thickness is greater than 0.15d(d), utilize arc former that the coil of the helical spring of winding is opened distance one by one after grinding, make the pitch of spring side be greater than the pitch of opposite side, thus the arc spring that angulation is greater than 45 degree, spring plane degree after shaping is less than 2mm, and angle is greater than 45 degree.Spring after shaping carries out second time stress relief annealing, and annealing temperature is 350 DEG C, and annealing time is 60 minutes, and the residual stress of spring surface is less than 250Mpa.After double annealing, with the steel wire ball blast of 0.7mm, the hardness of shot is greater than 600HV, in the shot-blasting machine that frequency of jettisoninging is not less than 50Hz, ball blast is carried out to spring, ball blast linear velocity is not less than 60m/s, ball blast intensity is 0.36A, and the residual compressive stress of ball blast rear surface is not less than-500Mpa, and subsurface maximum residual stress is not less than-700Mpa.Second time ball blast is carried out for the first time after ball blast, adopt the steel wire ball blast of 0.4mm, ball blast intensity is 0.25, after second time ball blast, spring surfaces externally and internally and coverage rate are not less than 100%, ball blast intensity is not less than 0.2A, and the residual compressive stress on surface is not less than-600Mpa, and subsurface maximum residual stress is not less than-800Mpa.Arc spring after secondary ball blast heating-up temperature in power press is 220 DEG C, is incubated 20 minutes, suppresses to also tight, and keep 3s, suppress 3 times and complete hot prestressing operation, suppressing in process, the actual temperature of spring is not less than 100 DEG C, and pressure setting is spring theory pressure and 2 times of moment of torsion.Spring after suppressing is delivered to screening installation and is carried out free angle sorting, perpendicularity sorting, radius of curvature sorting, angular rigidity and operation torque test, fatigue life test.Above-mentioned free angle, perpendicularity, radius of curvature select according to customer requirement.Angular rigidity and moment of torsion carry out on arc spring machine for testing torsion, and machine for testing torsion coordinates the test fixture mated with spring arc radius, can accurately the progress curve of measuring spring and return curve, and automatically can calculate the angular rigidity of spring.Qualified spring after sorting and fatigue test, applying preventive by dipping oil completes surperficial antirust treatment, the spring packaging warehouse-in after antirust treatment.
Claims (8)
1. a processing technology for arc spring, is characterized in that: comprise following operation:
The first step, wind spring, by steel wire stock according to prefabricated height, external diameter and the number of turns, the two ends of spring are also tight, be wound into columniform helical spring;
Second step, for the first time stress relief annealing;
3rd step, mill spring;
4th step, to annealing after spring each circle carry out one by one open distance, make the pitch of spring side be greater than the pitch of opposite side, linear springs become arc spring; Have passed through annealing eliminate harmful residual tension and mill spring after, carry out camber line more shaping, distance is carried out out in columned spring side, form arc spring, arc spring natural torsion after shaping becomes an arc, and between inner side and outside steel wire, spacing unevenness is less than 0.5mm;
5th step, second time stress relief annealing;
6th step, ball blast, adopts twice ball blast, first time the diameter of ball blast and intensity be greater than diameter and the intensity of the second ball blast;
7th step, hot prestressing;
8th step, sorting;
9th step, angular rigidity and torsion-testing,
Tenth step, fatigue life test;
11 step, surperficial antirust treatment.
2. the processing technology of a kind of arc spring according to claim 1, it is characterized in that: before wind spring, select raw material, raw-material case hardness is greater than 51HRC, the raw-material contraction percentage of area is greater than 35%, without the non-metallic inclusion more than 15 microns in raw-material section radius 1/3 scope, the injurous defect of raw material surface more than 40 microns answers spray paint as remarkable mark.
3. the processing technology of a kind of arc spring according to claim 1 and 2, it is characterized in that: after described wind spring first time stress relief annealing temperature at 320 DEG C ~ 470 DEG C, annealing time is at 30-65 minute, and effective temperature retention time of tempering furnace is greater than 40% of the spring turnover stove time.
4. the processing technology of a kind of arc spring according to claim 1 and 2, it is characterized in that: the temperature of described second time stress relief annealing is at 200 DEG C ~ 450 DEG C, annealing time was at 20 ~ 60 minutes, and effective temperature retention time of tempering furnace is greater than 40% of the spring turnover stove time.
5. the processing technology of a kind of arc spring according to claim 1 and 2, it is characterized in that: described ball blast adopts Caterpillar type shot blasting machine to carry out ball blast, the impelling material of ball blast is steel wire cut pill, the hardness of steel wire cut pill is greater than 600HV, impelling shot linear velocity is not less than 60m/s, first time, the diameter of ball blast was 0.4 ~ 0.8mm, and the diameter of second time ball blast is 0.2 ~ 0.6mm.
6. the processing technology of a kind of arc spring according to claim 1 and 2, it is characterized in that: described hot prestressing temperature is set as 180 DEG C ~ 280 DEG C, temperature retention time was at 10 ~ 30 minutes, pressure setting is spring theory pressure and 1.2 ~ 2 times of moment of torsion, suppressing in process, the actual temperature of spring is not less than 50 DEG C, and spring is depressed into and tight rear stop 0.5 ~ 15s by power press, and suppressing number of times is 1 ~ 5 time.
7. the processing technology of a kind of arc spring according to claim 1 and 2, is characterized in that: described sorting step comprises radius of curvature sorting, angular sorting and perpendicularity sorting.
8. the processing technology of a kind of arc spring according to claim 1 and 2, is characterized in that: the radian of the spring after arc wind spring is greater than π/4.
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| CN201110330177.4A CN102501009B (en) | 2011-10-27 | 2011-10-27 | Processing technology of arc-shaped spring |
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| CN201110330177.4A CN102501009B (en) | 2011-10-27 | 2011-10-27 | Processing technology of arc-shaped spring |
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| CN102501009B true CN102501009B (en) | 2014-12-24 |
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| CN106893843A (en) * | 2017-03-23 | 2017-06-27 | 无锡丰力弹簧有限公司 | The production technology of extension spring |
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| JP7227251B2 (en) | 2017-08-24 | 2023-02-21 | ルソール リベルテ インコーポレイティド | Coil spring and method of making same |
| CN108994738A (en) * | 2018-08-14 | 2018-12-14 | 山东汽车弹簧厂淄博有限公司 | Double ball blast surface strengthening technologies |
| CN111804854A (en) * | 2019-04-11 | 2020-10-23 | 永嘉县三和弹簧有限公司 | Machining process of arc-shaped spring |
| CN110079655A (en) * | 2019-05-06 | 2019-08-02 | 苏州德格斯精密制造有限公司 | A kind of manufacturing method of high yield spring |
| CN110681807B (en) * | 2019-08-27 | 2021-06-29 | 泰州市苏源汽车配件有限公司 | Spring curling and forming treatment process applied to display screen steering system |
| CN112695435B (en) * | 2020-12-25 | 2021-09-24 | 厦门市能诚电子科技有限公司 | Production process and equipment of slingshot wire |
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| EP0140202A2 (en) * | 1983-10-14 | 1985-05-08 | Baumann & Cie. AG | Method of making a spiral drive spring |
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| EP0140202A2 (en) * | 1983-10-14 | 1985-05-08 | Baumann & Cie. AG | Method of making a spiral drive spring |
| CN101092014A (en) * | 2007-05-16 | 2007-12-26 | 邵承玉 | Technique for fabricating arched spring in use for hydraulic torque converter of car, and dedicated equipment |
| CN101786221A (en) * | 2010-02-24 | 2010-07-28 | 钱江弹簧（北京）有限公司 | Method for processing arc spring |
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