CN103978086A - Process for machining corrugated pipe fitting by means of electromagnetic pre-deformation forming technique - Google Patents
Process for machining corrugated pipe fitting by means of electromagnetic pre-deformation forming technique Download PDFInfo
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- CN103978086A CN103978086A CN201410242448.4A CN201410242448A CN103978086A CN 103978086 A CN103978086 A CN 103978086A CN 201410242448 A CN201410242448 A CN 201410242448A CN 103978086 A CN103978086 A CN 103978086A
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Abstract
The invention discloses a process for machining a corrugated pipe fitting by means of an electromagnetic pre-deformation forming technique. The process includes the steps of (1) pipe fitting installation and (2) discharging forming of the corrugated pipe fitting, wherein in the step of pipe fitting installation, the pipe fitting is fixed well through a pipe fitting restraint device, the pipe fitting restraint device is overlapped with the axis of the pipe fitting, and a solenoid coil is arranged in the portion, needing to form, in the pipe fitting; in the step of discharging forming of the corrugated pipe fitting, the electric capacity of a charging capacitor set of the solenoid coil is 768-1152 mu F, a discharging control switch is turned off, the capacitor set is discharged through the solenoid coil, expansion and deformation of the pipe fitting are caused and corrugation is formed. The process has the following technical advantages that the corrugated aluminum alloy energy-absorption pipe fitting is machined by means of the electromagnetic pre-deformation forming technique, the method is easy and convenient to carry out, operations are easy to carry out, the forming speed is high, and cost is saved; the shape and the size of corrugation can be effectively controlled, and adaptability needed by energy absorption is flexible; yield strength of materials on the expansion portion is quite different from that on the trough positions, the strength of the pipe fitting in the axial direction is different, and the deformation mold is controllable; and energy absorbing efficiency of a thin-walled round pipe can be obviously improved.
Description
Technical field
The present invention relates to metal structure processing technique field, be specially a kind of employing electromagnetism and become in advance forming technique processing corrugated aluminium alloy energy-absorbing pipe fitting technique.
Background technology
Thin-walled metal member, as buffering energy-absorbing element, is widely used in the impact kinetic energy dissipative system of nearly all vehicles such as automobile, steamer and aircraft.Thin-walled metal member is mainly to lean on the plastic deformation of self to absorb the impact kinetic energy in vehicle collision, in the used time of doing that is subject to bump stroke, its failure mode is stable, can controllably by plastic deformation own, absorb and consumed energy, and produce certain crush stroke, thereby reach the kinetic energy that absorbs vehicle, reduce the object of vehicle deceleration.From the viewpoint of energy absorption capacity, the deformation pattern of the thin-wall construction under Axial Loads can be divided three classes: progressive distortion, Euler distortion and the mixed deformation pattern of collapsing, the main distinction is the deformation mechanism difference that forms plastic hinge.Thin-wall circular tube is that a class formation form is simple, and widely used energy absorbing structure, is subject to extensive concern, and relevant research work is also carried out the earliest, also more deep.Pipe is according to the difference of material and physical dimension, and deformation pattern has following a few class: axisymmetric deformation pattern (also referred to as Deformed ring pattern or accordion deformation pattern), non-axisymmetric deformation pattern (also referred to as diamond deformation pattern or Yoshimura pattern), mixed deformation pattern and Euler's deformation pattern.Under axial compression load effect, at ratio of wall thickness to size, compared with a hour pipe, there is nonaxisymmetrical diamond deformation pattern; And pipe generation axisymmetric deformation pattern or mixed deformation pattern during wall thickness and caliber larger; Long micropipe produces whole Euler buckling deformation pattern.But thin-wall circular tube energy absorption efficiency is not high enough, can not meet the demand in some field.
Summary of the invention
The object of this invention is to provide a kind of corrugated aluminium alloy energy-absorbing pipe fitting that adopts electromagnetism to become in advance forming technique processing pipe fitting technique and production, thereby solve the not high enough problem of thin-wall circular tube energy absorption efficiency of using at present.
Technical scheme of the present invention is, a kind of technique that adopts electromagnetism to become in advance forming technique processing corrugated pipe fitting, and step is as follows:
Step 1: pipe fitting is installed; Adopt pipe fitting restraint device that pipe fitting is fixed to pipe fitting, pipe fitting restraint device and pipe fitting axis coinciding, be placed in solenoid coil at the position of the needs shaping of inside pipe fitting;
Step 2: the electric discharge of bellows part is shaped; The capacitance of the charging capacitor group of solenoid coil is 768-1152 μ F, closes discharge control switch, and capacitor group is discharged by solenoid coil; Cause the bulging distortion of pipe fitting, form ripple, the curring time of ripple is about 200 μ s.
Distance between ripple, the displacement of going forward one by one by solenoid coil is controlled and is regulated.
The height of ripple, regulates by controlling the discharge energy of capacitance of the charging capacitor group of solenoid coil.
The width of ripple, the coil turn by solenoid coil regulates.
The sectional area of the wire of described solenoid coil is 3mm * 5mm, and the number of turn is more than 3 circles.
Described pipe fitting is thin-wall aluminum alloy pipe fitting.
The present invention has following technique effect, and 1, adopt electromagnetism to become in advance forming technique processing corrugated aluminium alloy energy-absorbing pipe fitting, method is easy, easy operating, and forming speed is fast, and cost-saving.2, can effectively control shape and the size of ripple, more flexible to the adaptability of absorption energy demand; 3, can make material produce obvious difference in bulging part with the yield strength of wave trough position, make pipe fitting different in axial strength size distribution, deformation pattern is controlled; 4, the Aluminum Alloy Tube based on electro-magnetic forming predeformation, can obviously improve the energy absorption efficiency of thin-wall circular tube.In one embodiment of the present of invention, Aluminum Alloy Tube is a bulging under 2600kv at discharge voltage, in radial velocity, is then conquassation under 200mm/min, and compression travel is 39mm, its energy absorption is 41.65J, than the not expansion tube 31.59J under same experimental conditions, exceeds 31.8%.
Accompanying drawing explanation
Fig. 1 is that the present invention adopts electromagnetism to become in advance the installation drawing of forming technique processing corrugated pipe fitting technique.
Fig. 2 is that solenoid coil of the present invention is placed in the profile after inside pipe fitting.
Fig. 3 is ripple principle schematic of the present invention's 3 circle coil solenoid coil electro-magnetic forming predeformation.
Two ripple principle schematic of Fig. 4 the present invention 3 circle coil solenoid coil electro-magnetic forming predeformation.
Ripple principle schematic of Fig. 5 the present invention 4 circle coil solenoid coil electro-magnetic forming predeformation.
Ripple principle schematic of Fig. 6 the present invention 5 circle coil solenoid coil electro-magnetic forming predeformation.
Fig. 7 solenoid coil circuit diagram of the present invention.
The specific embodiment
Below in conjunction with specific embodiment, further set forth the present invention.
As shown in Figure 1, Figure 2, shown in Fig. 7, adopt electromagnetism to become in advance the building mortion of forming technique processing corrugated aluminium alloy energy-absorbing pipe fitting, it comprises solenoid coil 1, pipe fitting 2 is aluminum alloy materials thin-wall circular tube, pipe fitting restraint device 3, pipe fitting restraint device 3 is contained on base 4, and solenoid coil 1 is contained on coil guide rod 5, and guide rod 5 is contained on guide rod gatherer 6.
Pipe fitting restraint device 3 is placed in two ends of pipe fitting 2, adopts the end restraint of both sides, can simplify building mortion, without fixed constraint devices such as bolt, screw rod, pressing plates, improves the efficiency of the assembling that is shaped.Solenoid coil 1 is successively wound around multi-turn by wire and forms, between adjacent wires, with high voltage insulating materials, separate, described solenoid coil 1 is at the two ends of pipeline circle L discharged in series gauge tap K, resistance R, rectifier Z, transformer P, charging capacitor group C mono-end is connected between electric control switch K and resistance R, and the other end is connected on the other end of pipeline circle L.
Embodiment 1, and the electric discharge apart from bellows part is shaped as shown in Figure 3, Figure 4 continuously.
Step 1: pipe fitting is installed; Pipe fitting 2 is placed in to pipe fitting restraint device 3 and is fixed, described pipe fitting 2 is thin-wall aluminum alloy pipe fitting, and wall thickness=1.2mm guarantees pipe fitting restraint device 3 and pipe fitting 2 axis coincidings, by coil guide rod 5, solenoid coil 1 is placed in to the position that pipe fitting 2 is wanted bulging.
Step 2: the number of turn of solenoid coil 1 is 3, the capacitance of charging capacitor group C is 768-1152 μ F, resistance R is 0.01 Ω-0.03 Ω, rectifier Z parameter is that reverse bias 50kV/ average current is not less than 3.5A, transformer P parameter is 220V-8kV, closes discharge control switch K, and capacitor group C discharges by solenoid coil 1, discharge voltage is 1000-3500V, and the curring time of ripple is about 200 μ s.By coil guide rod 5, solenoid coil 1 is placed in the pipe fitting 2 of the circular aluminium alloy of thin-walled, when solenoid coil 1 passes through By Impulsive Current, coil space just produces uniform strong pulsed magnetic field, at Aluminum Alloy Tube 2 inner surfaces, produce induced-current is eddy current simultaneously, and this induced-current produces inductive impulse magnetic field in space.Discharging moment, the induced-current of pipe fitting 2 inner surfaces is contrary with the discharge current flow direction in solenoid coil 1, in the intensive gap between solenoid coil 1 and pipe fitting 2 of the magnetic line of force, the intensive magnetic line of force has expansion feature, thereby pipe fitting 2 inner surfaces are subject to a radially outside surge effect.When pipe fitting 2 is stressed while reaching yield point, will cause the bulging distortion of pipe fitting 2, thereby form a ripple that waviness width A is about 10mm.Fixed constraint device and pipe fitting are motionless, and solenoid coil 1 is pushed ahead in pipe fitting 2 in the mode of going forward one by one, and behind second ripple precalculated position, repeat said process, form second ripple.Can solenoid coil 1 constantly be gone forward one by one by coil guide rod 5, realize the shaping of a plurality of equidistant ripples.
Step 3: solenoid coil 1 is taken out, then pipe fitting restraint device 3 is taken off to the bellows part obtaining.
Embodiment 2, and the electric discharge of different spacing bellows part is shaped.
Step 1, with embodiment 1
Step 2: by adjusting the amount of going forward one by one of 5 pairs of solenoid coils 1 of coil guide rod, be processed into different spacing bellows part, a is the spacing between ripple.Close discharge control switch K, capacitor group C discharges by solenoid coil 1, and parameter is identical with embodiment 1, under the effect of electromagnetic force, forms a ripple.Guarantee that pipe fitting restraint device 3 and pipe fitting 2 are motionless, the solenoid coil 1 larger distance of going forward one by one in pipe fitting 2 inside, the spacing between ripple increases, thereby forms the ripple of different spacing.By the amount of going forward one by one of continuous adjustment solenoid coil 1, at pipe fitting 2, form the ripple of different spacing.
Step 3: with embodiment 1.
Embodiment 3, and different waviness width pipe fittings are discharged into, as shown in Figure 5, Figure 6.
Step 1, with embodiment 1
Step 2, need to increase pipe fitting waviness width can realize by increasing solenoid coil 1 coil turn, the width that A is ripple, Fig. 5 coil number of turn is 4, Fig. 6 centre circle number of turn is 5.Close discharge control switch K, capacitor group C discharges by solenoid coil 1, and parameter is identical with embodiment 1, pipe fitting 2 ripple of wider width of can being shaped that is shaped under the effect of electromagnetic force.
Step 3: with embodiment 1.
The present invention's ripple that is shaped on the circular pipe fitting of thin-walled, ripple number, width, highly, adjustment and the coupling of the concrete dimensional parameters such as spacing have a significant impact whole device energy-absorbing effect, concrete numerical value is determined according to real impact energy concrete condition.
The shape of solenoid coil 1, size, size, the number of turn can be shaped and need to formulate according to reality.
On pipe fitting 2, be shaped and between ripple, have trough, bulging part obviously improves at the high strain rate lower yield strength of electro-magnetic forming, and trough intensity is lower, when Aluminum Alloy Tube generation axial impact, at trough, place collapses distortion, and the Aluminum Alloy Tube based on electro-magnetic forming, can obviously improve the energy absorption efficiency of the circular pipe fitting of thin-walled.
Device characteristic of the present invention is not subject to the restriction of above-mentioned example.
Claims (6)
1. adopt electromagnetism to become in advance a technique for forming technique processing corrugated pipe fitting, it is characterized in that: step is as follows:
Step 1: pipe fitting is installed; Adopt pipe fitting restraint device that pipe fitting is fixed to pipe fitting, pipe fitting restraint device and pipe fitting axis coinciding, be placed in solenoid coil at the position of the needs shaping of inside pipe fitting;
Step 2: the electric discharge of bellows part is shaped; The capacitance of the charging capacitor group of solenoid coil is 768-1152 μ F, closes discharge control switch, and capacitor group is discharged by solenoid coil; Cause the bulging distortion of pipe fitting, form ripple, the curring time of ripple is about 200 μ s.
Step 3: solenoid coil is taken out, then pipe fitting restraint device is taken off, obtain bellows part.
2. a kind of technique that adopts electromagnetism to become in advance forming technique processing corrugated pipe fitting according to claim 1, is characterized in that: the distance between ripple, the displacement of going forward one by one by solenoid coil is controlled and regulated.
3. a kind of technique that adopts electromagnetism to become in advance forming technique processing corrugated pipe fitting according to claim 1, is characterized in that: the height of ripple, regulates by controlling the discharge energy of capacitance of the charging capacitor group of solenoid coil.
4. a kind of technique that adopts electromagnetism to become in advance forming technique processing corrugated pipe fitting according to claim 1, is characterized in that: the width of ripple, the number of turn of the coil by solenoid coil regulates.
5. a kind of technique that adopts electromagnetism to become in advance forming technique processing corrugated pipe fitting according to claim 1, is characterized in that: the sectional area of the wire of described solenoid coil is 3mm * 5mm, and the number of turn is more than 3 circles.
6. according to a kind of technique that adopts electromagnetism to become in advance forming technique processing corrugated pipe fitting described in claim 1 to 5, it is characterized in that: described pipe fitting is thin-wall aluminum alloy pipe fitting.
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Cited By (8)
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| JP6426240B1 (en) * | 2017-07-12 | 2018-11-21 | 株式会社神戸製鋼所 | Apparatus and method for electromagnetically forming aluminum pipe member |
| JP6426241B1 (en) * | 2017-07-12 | 2018-11-21 | 株式会社神戸製鋼所 | Electromagnetic forming apparatus for aluminum pipe members |
| CN109848280A (en) * | 2019-03-13 | 2019-06-07 | 中南大学 | A kind of the subregion electromagnetic forming method and forming device of bellows |
| CN110000271A (en) * | 2019-05-21 | 2019-07-12 | 哈尔滨工业大学 | A kind of bellows electromagnetic pulse forming device and method |
| WO2019168136A1 (en) * | 2018-03-02 | 2019-09-06 | 株式会社神戸製鋼所 | Electromagnetic forming method |
| CN110799282A (en) * | 2017-07-12 | 2020-02-14 | 株式会社神户制钢所 | Method for forming pipe member |
| CN111842586A (en) * | 2020-06-18 | 2020-10-30 | 上海航天设备制造总厂有限公司 | Electromagnetic pulse forming method and device for aluminum alloy corrugated pipe |
| CN113909369A (en) * | 2021-11-09 | 2022-01-11 | 核工业理化工程研究院 | Electromagnetic forming method for single-wave corrugated pipe |
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| CN110799283A (en) * | 2017-07-12 | 2020-02-14 | 株式会社神户制钢所 | Electromagnetic forming device and electromagnetic forming method for aluminum pipe member |
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| CN109848280A (en) * | 2019-03-13 | 2019-06-07 | 中南大学 | A kind of the subregion electromagnetic forming method and forming device of bellows |
| CN110000271B (en) * | 2019-05-21 | 2020-06-16 | 哈尔滨工业大学 | Electromagnetic pulse forming device and method for corrugated pipe |
| CN110000271A (en) * | 2019-05-21 | 2019-07-12 | 哈尔滨工业大学 | A kind of bellows electromagnetic pulse forming device and method |
| CN111842586A (en) * | 2020-06-18 | 2020-10-30 | 上海航天设备制造总厂有限公司 | Electromagnetic pulse forming method and device for aluminum alloy corrugated pipe |
| CN113909369A (en) * | 2021-11-09 | 2022-01-11 | 核工业理化工程研究院 | Electromagnetic forming method for single-wave corrugated pipe |
| CN113909369B (en) * | 2021-11-09 | 2024-03-19 | 核工业理化工程研究院 | Electromagnetic forming method for single wave corrugated pipe |
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Application publication date: 20140813 |