CN102653034A - Pulsed laser welding method for high-pressure sealed valve body component - Google Patents
Pulsed laser welding method for high-pressure sealed valve body component Download PDFInfo
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- CN102653034A CN102653034A CN2011104241427A CN201110424142A CN102653034A CN 102653034 A CN102653034 A CN 102653034A CN 2011104241427 A CN2011104241427 A CN 2011104241427A CN 201110424142 A CN201110424142 A CN 201110424142A CN 102653034 A CN102653034 A CN 102653034A
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Abstract
The invention discloses a pulsed laser welding method for a high-pressure sealed valve body component and aims at providing a processing method for forming a continuous compact weld bead, which has the advantages of stable quality, higher efficiency, appropriate fusion depth of a joint after welding, regular weld joint, bright joint, uniform melting and mutually overlapped laser spots. The method disclosed by the invention is realized through the following technical scheme comprising the following steps of: (a) removing oxides on the surface of a weld and washing a joint part by a washing agent; (b) enabling a valve seat to be tightly close to a sealing gasket through a clamp, clamping on a three-jaw chuck, tilting a rotating table for 45 degrees and melting an angle joint of the valve body component; and (c) setting single pulse energy according to the characteristics of material and enabling a pulse waveform to be steep at the front and gentle at the back, thereby rapidly increasing laser energy to a peak value, rapidly heating, improving absorbability, then slowly lowering the temperature, maintaining the temperature for heating continuously, avoiding violent splashing, simultaneously increasing the fusion depth, melting the angle joint into a whole, matching with reasonable welding speed and pulse frequency, and enabling the laser spots to be mutually overlapped for forming the continuous compact weld bead.
Description
Technical field
The invention relates to the method for high pressure sealing valve component pulse laser welding, particularly be adapted to the welding material difference, require to bear the high pressure sealing product that pressure is big, slip is low.
Background technology
Valve component is a typical high pressure sealing product on the aero-engine, and the precision of its manufacturing directly influences the key property of aero-engine.Therefore, valve component is connected with strict demand.Usually the connection of high pressure sealing valve component mainly contains whole machining and welding processing dual mode.
Adopt whole machining, complex process, manufacturing cost height, and production efficiency is low; Be not easy to produce in batches, and this valve component works under particular surroundings, valve seat is a heat resisting steel; Pad is the 0Cr18Ni9Ti austenitic stainless steel, and foreign material is formed can't carry out whole machining.
As last procedure, postwelding does not have surplus processing, and is therefore strict to the welding Deformation control, more do not allow weld seam to penetrate gasket seal, otherwise pad loses sealing function.Adopt conventional welding method-argon arc welding; Quantity of heat given up is excessive, the heat affected area is wide, welding deformation is serious; Axiality is uncontrollable in 0.05mm, can't satisfy instructions for use, is difficult to from technological parameter, welding quality control effectively; Can't fundamentally avoid the welding deformation phenomenon, cause part to scrap.
Adopt the conventional laser welding method, power density is too high, penetration power is strong excessively, energy is too concentrated, and it is even inadequately to occur shaping surface easily; Back 1/3 section surface of weld seam has depression defect, and the main cause that produces this defective is that thermal capacity is less relatively because pad is thin excessively; The temperature rise of different time section part is widely different in the welding process, particularly back 1/3 section of welding ring weld seam, because the heat of the heating of laser beam welding and leading portion weld seam is conducted; It is higher that part heats up, and weld metal fusing amount wants big for preceding relatively 2/3 section, more preceding 2/3 section wide and form deep mixed depressed phenomenon of appearance of weld; Thereby cause the part post welding distortion serious; Axiality is uncontrollable in 0.05mm, when weldering surpasses stopper line deeply, the part very easily occurs and burns, welds leakage, causes part to scrap.
Summary of the invention
The objective of the invention is weak point to above-mentioned prior art; A kind of steady quality is proposed, efficient is higher, welding back, joint fusion penetration is moderate, weld seam is regular, joint is bright, fusing is even, the processing method of the continuous fine and close welding bead of the overlapped formation of LASER SPECKLE.
In order to achieve the above object, the present invention provides the method for high pressure sealing valve component pulse laser welding, it is characterized in that, comprises the steps:
(a) at first remove the surperficial oxide of part place to be welded joint area with mechanical means, use the organic washing agent then, the butt welded seam joint area cleans;
(b) through special fixture valve seat and corner connection place of gasket seal weld seam are fitted tightly together;
(c) according to the characteristics of material, the individual pulse energy is set rationally, impulse waveform adopts " preceding steep back is slow "; Make laser energy be climbed to peak value, material rapidly heating slowly descends subsequently and keeps and continue heating to improve absorbability; Increase fusion penetration when avoiding splashing strongly; Corner connection place position is fused into one, through rational Match speed of welding, pulse frequency, the welding bead that makes the continuous densification of the overlapped formation of LASER SPECKLE.
The present invention has following beneficial effect than prior art:
The present invention is provided with impulse waveform through program, adopts pulse laser to a valve component segmentation welding foreign material, the whole connection, and utilize method that equipment is not had other requirements, on general laser welder, can accomplish the welding of high pressure sealing valve component.Laser welding apparatus is not had other requirements, control easy, produce in batches steady quality, accurately controlled, efficient is higher; Fusion penetration is moderate after the laser weld, weld seam is regular, joint is bright, fusing is even, and spot is overlapping, and welding bead is fine and close; Pulse laser welding method according to the invention with respect to whole machining process; Simple, the low cost of manufacture of technology, and production efficiency is high is little with respect to other welding methods distortion, precision is high; With respect to the conventional laser welding, good stability, high, the good sealing effect of reliability.Processing method according to the invention is that the segmentation of high pressure sealing valve component is welded; The whole connection; Required technological process is simple, and shaping efficiency is high, and the postwelding axiality is controlled in the 0.02mm; Heat distortion amount is minimum, through the high pressure sealing test, weld strength can be born 40MPa pressure, slip is stabilized in 3 * 10
-10Pam
3/ s, product percent of pass reaches 100%, meets design requirement fully.
Description of drawings
Fig. 1 is the sketch map of high pressure sealing valve component pulse laser welding of the present invention.
Among the figure: 1. valve seat, 2. gasket seal.
The specific embodiment
Referring to Fig. 1.To further specify the present invention in following examples, these embodiment only are used to the present invention is described and the present invention are not limited.
Prepare before the weldering.With the oxide of mechanical means removal part joint surface, weldering is preceding with the cleaning of organic washing agent acetone near the strictness place to be welded joint.Adopt rigid fixation, valve seat and pad are fitted tightly the anchor clamps of packing into, " eight point symmetries, bolted ", the size of pretightning force is by threaded adjustment.Contraction through " side top go up press " control postwelding axle, footpath both direction, reducing angular deformation and flexural deformation, thereby the axiality of control valve seat and pad guarantees the valve component sealing effectiveness to greatest extent.
According to stainless steel and heat-resisting steel material weld characteristics; At first load module circumferential seam place is implemented some somes pulse laser tack-welds; Tack weld is uniformly distributed with on girth weld; Cause place to be welded to be dehisced to reduce the distortion that girth weld causes because of local heating in welding process, to keep from heat simultaneously, guarantee welded seal property.
Select laser peak power, pulse width, defocusing amount laser parameter.In the selection of laser parameter, can select, laser peak power is 20%～30%, and pulse width is 25～35ms, and defocusing amount is in-0.5～0mm technological parameter, gets any concrete numerical value.Setting the pulse laser waveform is " preceding steep back is slow ", helps two kinds of materials and heats rapidly, improves absorbent properties; After laser is climbed to peak value according to certain impulse waveform slope; Producing to splash for fear of the metal violent evaporation increases fusion penetration simultaneously, and peak value of pulse should reduce rapidly and keep and continues heating, when the situation that steam pressure reduces; Help before molten pool metal begins crystallization, to fill up pit, so that molten metal is filled in the pit that forms in the pulse initial period.Prolong pulse back edge, slowly descend, prevent to form pore after the molten pool metal condensation, increase the pulse duration, thoroughly get rid of the non-dissolved gas in the molten bath.Laser pulse " fast liter is slow to fall "; The reasonable distribution welding energy; Reduce the reflection of material for laser light energy, reach the effect of " weld preheating, postheating ", to eliminate the sensitiveness of welding posterior spiracle, residual stress and weld cracking; The heat that produced when utilizing the laser rise and fall is implemented the moment welding, and the valve component position that is tightly connected is fused into one.Reset laser pulse shape and technological parameter and can carry out the welding of different-thickness material.
Peak merit value rationally is set; Focal position of laser is very big to the fusion penetration influence, setting under the less pulse power, focal position of laser is adjusted to about the following 0.5mm of surface of the work; Bring into play laser penetration effectiveness to greatest extent and make appearance of weld good, to eliminate the uneven defective of fusion penetration.
Select speed of welding, pulse frequency technological parameter.On selection of process parameters, can select, speed of welding is 10～15 mm/s, pulse frequency is 50～60Hz, through rational Match speed of welding, pulse frequency, the welding bead that makes the continuous densification of the overlapped formation of LASER SPECKLE.
For reducing to be out of shape accumulation, avoid welding depression, penetrate, take " segmentation welding, the whole connection " during welding, reduce segmentation weld seam handing-over length as far as possible, avoid material to be heated repeatedly, produce distortion.
The side-blown mode that adds of directly blowing is adopted in argon shield in welding; Directly blow the non-metallic inclusion in the evaporated metal steam in advance; Purify the fusion zone and obtain quality weld, side-blown helps reducing the plasma cloud that produces in the welding, increases welding penetration; Directly blow and add side-blown and carry out synchronously, can obtain desirable welding effect.
Joint welding is molten wide, fusion penetration is determined by welding procedure and technological parameter.Valve component for unlike material, thickness only need adjust impulse waveform, reset technological parameter can change the input welding heat and accomplish processing.
Through above-mentioned measure, pulse laser is integral the valve component molten solder, realize that the high strength of two kinds of different materials is tightly connected.Reset impulse waveform, technological parameter and can carry out the high pressure sealing product welding of different-thickness, unlike material.
Claims (7)
1. the method for a high pressure sealing valve component pulse laser welding is characterized in that, comprises the steps:
(a) remove part place to be welded oxide on surface, clean the butt joint position;
(b) with anchor clamps valve seat and gasket seal are fitted tightly together, clamping on scroll chuck, the turntable 45 ° of laser fusion valve component corner connection place positions that tilt;
(c) adopt " preceding steep back is slow " impulse waveform to heat rapidly; Make laser energy be climbed to peak value; Slowly descend subsequently and keep and continue heating, increase fusion penetration when avoiding splashing strongly, corner connection place position is fused into one; The welding bead that coupling speed of welding and pulse frequency, the overlapped formation of LASER SPECKLE are fine and close continuously.
2. the method for high pressure sealing valve component pulse laser welding according to claim 1; It is characterized in that in the selection of laser parameter, laser peak power is 20%～30%; Impulse waveform is that preceding steep back is slow; Pulse width is 25～35ms, and defocusing amount is in-0.5～0mm technological parameter, gets any concrete numerical value.
3. the method for high pressure sealing valve component pulse laser welding according to claim 1 is characterized in that, increases pulse duration 25～30ms; Thoroughly get rid of the non-dissolved gas in the molten bath; Prevent to form pore after the molten pool metal condensation, when steam pressure reduces, prolong pulse back edge; Slowly descend, so that molten metal is filled in the pit that forms in the pulse initial period.
4. the method for high pressure sealing valve component pulse laser welding according to claim 1; It is characterized in that; Focal position of laser is adjusted to about the following 0.5mm of surface of the work, brings into play laser penetration effectiveness to greatest extent and make appearance of weld good, to eliminate the uneven defective of fusion penetration.
5. the method for high pressure sealing valve component pulse laser welding according to claim 1 is characterized in that, on technological parameter, selecting speed of welding is 10～15 mm/s, and pulse frequency is 50～60Hz.
6. the method for high pressure sealing valve component pulse laser welding according to claim 1 is characterized in that, takes " segmentation welding, the whole connection " during welding, reduces segmentation weld seam handing-over length as far as possible, avoids material to be heated repeatedly, produces distortion.
7. the method for high pressure sealing valve component pulse laser welding according to claim 1, its spy
Levy and be that argon shield is adopted to blow side to add and directly blown complex method in welding, the non-metallic inclusion in the evaporated metal steam purifies the fusion zone and obtains quality weld in advance, and reduces plasma cloud, increases welding penetration.
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Cited By (14)
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|---|---|---|---|---|
| CN102962578A (en) * | 2012-11-19 | 2013-03-13 | 成都泛华航空仪表电器有限公司 | Method for welding eccentric circumferential seams by using electron beam scanning |
| CN103672108A (en) * | 2012-09-26 | 2014-03-26 | 浙江三花汽车零部件有限公司 | Electromagnetic valve and welding method of electromagnetic valve |
| CN104227235A (en) * | 2013-06-14 | 2014-12-24 | 日立汽车系统株式会社 | Laser welding method, welding component, fuel injection valve |
| CN104516243A (en) * | 2013-09-30 | 2015-04-15 | 兄弟工业株式会社 | Developing device, blade unit, and developing device manufacturing method |
| CN105618929A (en) * | 2016-03-04 | 2016-06-01 | 上海空间推进研究所 | Laser welding method for accurate control over heat input |
| CN105643104A (en) * | 2016-03-04 | 2016-06-08 | 上海空间推进研究所 | Laser welding method for precisely controlling weld penetration |
| CN106001924A (en) * | 2016-05-30 | 2016-10-12 | 远利（天津）海业机械工程有限公司 | Laser additive remanufacturing and erosion-resistant surface strengthening technological method for erosive abraded precision workpiece in drilling tool of directional well |
| CN106392325A (en) * | 2016-11-15 | 2017-02-15 | 湖北三江航天红阳机电有限公司 | Laser welding method for stainless steel thick-wall pressure container |
| CN106624363A (en) * | 2015-11-01 | 2017-05-10 | 四川泛华航空仪表电器有限公司 | Head-tail laser butt welding method for shaft seal spring |
| CN107107249A (en) * | 2014-09-25 | 2017-08-29 | 德国派斯塔钢制阀门公司 | For the method for the housing mid-section part for manufacturing high-pressure stop valve |
| CN107414300A (en) * | 2017-08-23 | 2017-12-01 | 四川九立微波有限公司 | A kind of method of the hybrid laser welding capping of high-power PIN switch modules |
| CN110120623A (en) * | 2018-02-05 | 2019-08-13 | 深圳光峰科技股份有限公司 | Sealing element and light emitting device |
| CN113146081A (en) * | 2021-03-30 | 2021-07-23 | 广西天正钢结构有限公司 | Steel structure bridge truss welding tool and welding method |
| CN113941775A (en) * | 2021-11-16 | 2022-01-18 | 天津市捷威动力工业有限公司 | Battery module dissimilar metal shell and welding method thereof |
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Cited By (21)
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| CN103672108A (en) * | 2012-09-26 | 2014-03-26 | 浙江三花汽车零部件有限公司 | Electromagnetic valve and welding method of electromagnetic valve |
| CN103672108B (en) * | 2012-09-26 | 2016-05-25 | 浙江三花汽车零部件有限公司 | Magnetic valve and welding method thereof |
| CN102962578A (en) * | 2012-11-19 | 2013-03-13 | 成都泛华航空仪表电器有限公司 | Method for welding eccentric circumferential seams by using electron beam scanning |
| CN104227235A (en) * | 2013-06-14 | 2014-12-24 | 日立汽车系统株式会社 | Laser welding method, welding component, fuel injection valve |
| CN104227235B (en) * | 2013-06-14 | 2016-05-11 | 日立汽车系统株式会社 | Method for laser welding, welded unit and Fuelinjection nozzle |
| CN104516243A (en) * | 2013-09-30 | 2015-04-15 | 兄弟工业株式会社 | Developing device, blade unit, and developing device manufacturing method |
| CN107107249B (en) * | 2014-09-25 | 2019-10-01 | 德国派斯塔钢制阀门公司 | Method for manufacturing the housing mid-section part of high-pressure stop valve |
| US10364908B2 (en) | 2014-09-25 | 2019-07-30 | STAHL-ARMATUREN PERSTA Gesellschaft mit beschraenkter Haftung | Method for producing a housing central part of a high-pressure slide gate valve |
| CN107107249A (en) * | 2014-09-25 | 2017-08-29 | 德国派斯塔钢制阀门公司 | For the method for the housing mid-section part for manufacturing high-pressure stop valve |
| CN106624363A (en) * | 2015-11-01 | 2017-05-10 | 四川泛华航空仪表电器有限公司 | Head-tail laser butt welding method for shaft seal spring |
| CN105618929B (en) * | 2016-03-04 | 2017-08-01 | 上海空间推进研究所 | The method for laser welding of heat input precision control |
| CN105643104B (en) * | 2016-03-04 | 2017-08-01 | 上海空间推进研究所 | The method for laser welding of accurate control weld penetration |
| CN105643104A (en) * | 2016-03-04 | 2016-06-08 | 上海空间推进研究所 | Laser welding method for precisely controlling weld penetration |
| CN105618929A (en) * | 2016-03-04 | 2016-06-01 | 上海空间推进研究所 | Laser welding method for accurate control over heat input |
| CN106001924A (en) * | 2016-05-30 | 2016-10-12 | 远利（天津）海业机械工程有限公司 | Laser additive remanufacturing and erosion-resistant surface strengthening technological method for erosive abraded precision workpiece in drilling tool of directional well |
| CN106392325A (en) * | 2016-11-15 | 2017-02-15 | 湖北三江航天红阳机电有限公司 | Laser welding method for stainless steel thick-wall pressure container |
| CN106392325B (en) * | 2016-11-15 | 2018-07-06 | 湖北三江航天红阳机电有限公司 | A kind of method for laser welding of stainless steel thick-walled pressure vessel |
| CN107414300A (en) * | 2017-08-23 | 2017-12-01 | 四川九立微波有限公司 | A kind of method of the hybrid laser welding capping of high-power PIN switch modules |
| CN110120623A (en) * | 2018-02-05 | 2019-08-13 | 深圳光峰科技股份有限公司 | Sealing element and light emitting device |
| CN113146081A (en) * | 2021-03-30 | 2021-07-23 | 广西天正钢结构有限公司 | Steel structure bridge truss welding tool and welding method |
| CN113941775A (en) * | 2021-11-16 | 2022-01-18 | 天津市捷威动力工业有限公司 | Battery module dissimilar metal shell and welding method thereof |
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Application publication date: 20120905 |