CN109596432A - A kind of Measurement die of tube forming limiting figure - Google Patents

A kind of Measurement die of tube forming limiting figure Download PDF

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Publication number
CN109596432A
CN109596432A CN201811427002.3A CN201811427002A CN109596432A CN 109596432 A CN109596432 A CN 109596432A CN 201811427002 A CN201811427002 A CN 201811427002A CN 109596432 A CN109596432 A CN 109596432A
Authority
CN
China
Prior art keywords
pipe end
formed punch
punch
sheath
tube forming
Prior art date
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.)
Pending
Application number
CN201811427002.3A
Other languages
Chinese (zh)
Inventor
徐炎
郑玉磊
刘兵
杨杰
童军
程奎
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
BAOLONG (ANHUI) AUTOMOTIVE Corp
Original Assignee
BAOLONG (ANHUI) AUTOMOTIVE Corp
Priority date (The priority date 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 date listed.)
Filing date
Publication date
Application filed by BAOLONG (ANHUI) AUTOMOTIVE Corp filed Critical BAOLONG (ANHUI) AUTOMOTIVE Corp
Priority to CN201811427002.3A priority Critical patent/CN109596432A/en
Publication of CN109596432A publication Critical patent/CN109596432A/en
Pending legal-status Critical Current

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Classifications

    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/08Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces
    • G01N3/10Investigating strength properties of solid materials by application of mechanical stress by applying steady tensile or compressive forces generated by pneumatic or hydraulic pressure
    • G01N3/12Pressure testing
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N3/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N3/02Details
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0014Type of force applied
    • G01N2203/0016Tensile or compressive
    • G01N2203/0019Compressive
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/003Generation of the force
    • G01N2203/0042Pneumatic or hydraulic means
    • G01N2203/0048Hydraulic means
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/0058Kind of property studied
    • G01N2203/0069Fatigue, creep, strain-stress relations or elastic constants
    • G01N2203/0075Strain-stress relations or elastic constants
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/026Specifications of the specimen
    • G01N2203/0262Shape of the specimen
    • G01N2203/0274Tubular or ring-shaped specimens
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/06Indicating or recording means; Sensing means
    • G01N2203/067Parameter measured for estimating the property
    • G01N2203/0676Force, weight, load, energy, speed or acceleration
    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N2203/00Investigating strength properties of solid materials by application of mechanical stress
    • G01N2203/02Details not specific for a particular testing method
    • G01N2203/06Indicating or recording means; Sensing means
    • G01N2203/067Parameter measured for estimating the property
    • G01N2203/0682Spatial dimension, e.g. length, area, angle

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  • Physics & Mathematics (AREA)
  • Health & Medical Sciences (AREA)
  • Life Sciences & Earth Sciences (AREA)
  • Chemical & Material Sciences (AREA)
  • Analytical Chemistry (AREA)
  • Biochemistry (AREA)
  • General Health & Medical Sciences (AREA)
  • General Physics & Mathematics (AREA)
  • Immunology (AREA)
  • Pathology (AREA)
  • Shaping Metal By Deep-Drawing, Or The Like (AREA)
  • Investigating Strength Of Materials By Application Of Mechanical Stress (AREA)

Abstract

The invention discloses a kind of Measurement dies of tube forming limiting figure, two pipe end mounting assemblies are mounted on mould bases and tubing installation position is collectively formed in arrangement up and down, the mounting base of each pipe end mounting assembly is equipped with die cavity close to tubing installation position side, formed punch is located in the die cavity, formed punch outer wall is equipped with the sealing structure being circular layout, sheath be set in outside formed punch and can vertical sliding be mounted in mounting base, pipe end holding tank is formed between sheath and formed punch, pressure sensor and liquid injection hole are arranged on formed punch, displacement sensor is used to detect the deformational displacement of outer pipe wall.Pass through the Measurement die of the tube forming limiting figure of above-mentioned optimization design, by being filled with liquid in mold cavity, so that inside pipe fitting pressure rise, swollen type occurs for tube wall, as tube wall deformation pipe range is shunk, both ends sheath is accordingly slided with tube wall, so that the pressure and displacement data of detection are more nearly applying working condition, ess-strain of true reflection pipe fitting during rising by type, data are more acurrate.

Description

A kind of Measurement die of tube forming limiting figure
Technical field
The present invention relates to metal pipe material field shaping technique more particularly to a kind of Measurement dies of tube forming limiting figure.
Background technique
Forming limit figure (Forming limit diagram-FLD) is also referred to as shaping limit curve (Forming Limit Curves), it is that local buckling limit engineering strain e1 and e2 by plate or tubing under differently strained path or the limit are true The strip-form region or curve that real strain stress 1 and ε 2 are constituted are that judgement material forms successfully and fails in metal material moulding molding An important judgment basis.Punching press, the type that rises process optimization, the side such as plates of automobile Materials Selection are being carried out using finite element simulation Face has important application.
Measurement material forming limit figure conventional method is production experiment test piece, and it is real to carry out mechanical performance using universal testing machine It tests, obtains material characteristic data, be depicted as limiting figure.This method cannot simulate tubing and rise molding and when interior high-pressure molding in water True environment, obtained data cannot reflect ess-strain situation of tubing during rising by type well, influence using limited Meta analysis tubing rise type when result.
Summary of the invention
To solve technical problem present in background technique, the present invention proposes a kind of measurement mould of tube forming limiting figure Tool.
A kind of Measurement die of tube forming limiting figure proposed by the present invention, comprising: mould bases, two pipe end mounting assemblies, Pressure sensor, displacement sensor;
Two pipe end mounting assemblies are mounted on mould bases and tubing installation position is collectively formed in arrangement up and down;
Each pipe end mounting assembly includes mounting base, formed punch and sheath, and mounting base is on the side of the tubing installation position Equipped with die cavity, formed punch is located in the die cavity, and formed punch outer wall is equipped with the sealing structure being circular layout, and sheath is set in outside formed punch And can vertical sliding be mounted in mounting base, between sheath and formed punch formed pipe end holding tank, at least one pipe end mounting assembly Formed punch be equipped with liquid injection hole;
Pressure sensor is arranged on the formed punch of at least one pipe end mounting assembly, and pressure sensor is for detecting in tubing Portion's pressure, displacement sensor are located at tubing installation position side for detecting the deformational displacement of outer pipe wall.
Preferably, jacket inner wall is equipped with anti-slip part.
Preferably, formed punch has the column structure extended vertically.
Preferably, sheath is equipped with annular guide surface close to tubing installation position one end inner edge, in the annular guide surface It is gradually increased radially adjacent to tubing installation position one end.
Preferably, two pipe end mounting assemblies are respectively upper pipe end mounting assembly and lower pipe end mounting assembly, upper pipe end peace Arrangement includes upper mounting seat, upper punch and upper jacket, and lower pipe end mounting assembly includes lower mounting seat, low punch and lower jacket, On the lower punch, pressure sensor is arranged on upper punch for the liquid injection hole setting.
Preferably, upper punch and low punch have the column structure being vertically arranged and the two is coaxially arranged.
It preferably, further include booster, booster is connected to the liquid injection hole.
Preferably, formed punch and sheath are removably mounted in mounting base.
In the present invention, the Measurement die of the tube forming limiting figure proposed, two pipe end mounting assemblies are mounted on mould bases Tubing installation position is collectively formed in upper and upper and lower arrangement, and the mounting base of each pipe end mounting assembly is close to tubing installation position side It is equipped with die cavity, formed punch is located in the die cavity, and formed punch outer wall is equipped with the sealing structure being circular layout, and sheath is set in outside formed punch Portion and can vertical sliding be mounted in mounting base, pipe end holding tank, pressure sensor and liquid injection hole are formed between sheath and formed punch It is arranged on the formed punch of at least one pipe end mounting assembly, displacement sensor is used to detect the deformational displacement of outer pipe wall.Pass through The Measurement die of the tube forming limiting figure of above-mentioned optimization design, it is reasonable in design, by being filled with liquid in mold cavity, make Inside pipe fitting pressure rise is obtained, swollen type occurs for tube wall, and as tube wall deformation pipe range is shunk, both ends sheath is accordingly slided with tube wall, To which the pressure and displacement data of detection are more nearly applying working condition, the true ess-strain for reflecting pipe fitting during rising by type, Obtained data are more acurrate true.
Detailed description of the invention
Fig. 1 is a kind of structural schematic diagram of the Measurement die of tube forming limiting figure proposed by the present invention.
Fig. 2 is that a kind of tubing of Measurement die of tube forming limiting figure proposed by the present invention installs the structure of original state Schematic diagram.
Fig. 3 is a kind of structural representation of the swollen type state of tubing of the Measurement die of tube forming limiting figure proposed by the present invention Figure.
Specific embodiment
As shown in Figures 1 to 3, Fig. 1 is a kind of structural representation of the Measurement die of tube forming limiting figure proposed by the present invention Figure, Fig. 2 are that a kind of tubing of Measurement die of tube forming limiting figure proposed by the present invention installs the structural representation of original state Figure, Fig. 3 are a kind of structural schematic diagram of the swollen type state of tubing of the Measurement die of tube forming limiting figure proposed by the present invention.
Referring to figs. 1 to 3, a kind of Measurement die of tube forming limiting figure proposed by the present invention, comprising: mould bases 1, two pipe Hold mounting assembly, pressure sensor 2, displacement sensor 3;
Two pipe end mounting assemblies are mounted on mould bases 1 and tubing installation position is collectively formed in arrangement up and down;
Each pipe end mounting assembly includes mounting base 4, formed punch 5 and sheath 6, and mounting base 4 is close to the tubing installation position one Side is equipped with die cavity, and formed punch 5 is located in the die cavity, and 5 outer wall of formed punch is equipped with the sealing structure being circular layout, and sheath 6 is set in The outside of formed punch 5 and can vertical sliding be mounted in mounting base 4, pipe end holding tank is formed between sheath 6 and formed punch 5, at least one The formed punch 5 of pipe end mounting assembly is equipped with liquid injection hole;
Pressure sensor 2 is arranged on the formed punch 5 of at least one pipe end mounting assembly, and pressure sensor 2 is used for detection pipe Material internal pressure, displacement sensor 3 are located at tubing installation position side for detecting the deformational displacement of outer pipe wall.
In the specific work process of the Measurement die of the tube forming limiting figure of the present embodiment, tubing is vertically installed at pipe On material installation position, tubing both ends are inserted into respectively in pipe end holding tank, and tubing both ends inner wall is close respectively at the sealing structure on formed punch Envelope cooperation;When work, low pressure liquid is injected into tubing by liquid injection hole first, after filling inside tubing is full, is constantly injected Highly pressurised liquid, overpressure are promoted, and start the type that rises under the action of hydraulic in the middle part of pipe fitting, and pressure sensor record pressure becomes at this time Change data, displacement sensor record tubing rise type position move delta data;As the area Zhang Xing constantly swells, in the meeting of tubing both ends The area Jian Zhangxing is shunk, and sheath is mobile to intermediate region together with tubing, until tubing rises type cracking, stops pressurization, so that whole A type process tubing that rises is all in the type state that freely rises;Finally, it according to the changing value of pressure and displacement, draws tubing and rises the type limit Figure.
In the present embodiment, the Measurement die of the tube forming limiting figure proposed, two pipe end mounting assemblies are mounted on It arranges on mould bases and up and down and tubing installation position is collectively formed, the mounting base of each pipe end mounting assembly is close to the tubing installation position Side is equipped with die cavity, and formed punch is located in the die cavity, and formed punch outer wall is equipped with the sealing structure being circular layout, and sheath is set in punching Head it is external and can vertical sliding be mounted in mounting base, pipe end holding tank, pressure sensor and note are formed between sheath and formed punch Fluid apertures is arranged on the formed punch of at least one pipe end mounting assembly, and displacement sensor is used to detect the deformational displacement of outer pipe wall. It is reasonable in design by the Measurement die of the tube forming limiting figure of above-mentioned optimization design, by being filled with liquid in mold cavity Body, so that inside pipe fitting pressure rise, swollen type occurs for tube wall, and as tube wall deformation pipe range is shunk, both ends sheath is corresponding with tube wall Sliding, so that the pressure and displacement data of detection are more nearly applying working condition, the true stress for reflecting pipe fitting during rising by type Strain, obtained data are more acurrate true.
In the specific embodiment of sheath, 6 inner wall of sheath is equipped with anti-slip part.
In the specific set-up mode of formed punch, formed punch 5 has the column structure extended vertically.
It is mounted in the pipeline section holding tank for the ease of pipe end, sheath 6 is in the one end of the tubing installation position Edge is equipped with annular guide surface, is gradually increased in the annular guide surface radially adjacent to tubing installation position one end;Meanwhile working as pipe When wall finds to extend out deformation under the action of internal hydraulic pressure, annular guide surface forms guide support to tube wall outer wall, prevents to pipe Wall causes secondary injury.
In other specific embodiments, two pipe end mounting assemblies are respectively upper pipe end mounting assembly and the installation of lower pipe end Component, upper pipe end mounting assembly include upper mounting seat, upper punch and upper jacket, lower pipe end mounting assembly include lower mounting seat, under Formed punch and lower jacket, on the lower punch, pressure sensor 2 is arranged on upper punch for the liquid injection hole setting;During the test, It inwardly fills the water from tubing bottom, rises so that tubing internal pressure is stablized, to guarantee tubing each position liquid when deformation occurs Stress equalization is pressed, while pressure is detected from top by pressure sensor, prevents lower end from generating by liquid injection hole fluid injection pressurization Pressure oscillation influences to detect accuracy.
In further specific embodiment, upper punch and low punch are coaxial with the column structure and the two being vertically arranged Arrangement.
It further include booster in other specific set-up modes, booster is connected to the liquid injection hole.
In order to be adapted to various sizes of tubing, formed punch 5 and sheath 6 are removably mounted in mounting base 4, thus according to pipe The adjustment of part inside/outside diameter size.
The foregoing is only a preferred embodiment of the present invention, but scope of protection of the present invention is not limited thereto, Anyone skilled in the art in the technical scope disclosed by the present invention, according to the technique and scheme of the present invention and its Inventive concept is subject to equivalent substitution or change, should be covered by the protection scope of the present invention.

Claims (8)

1. a kind of Measurement die of tube forming limiting figure characterized by comprising mould bases (1), two pipe end mounting assemblies, Pressure sensor (2), displacement sensor (3);
Two pipe end mounting assemblies are mounted on mould bases (1) and tubing installation position is collectively formed in arrangement up and down;
Each pipe end mounting assembly includes mounting base (4), formed punch (5) and sheath (6), and mounting base (4) is installed close to the tubing Position side is equipped with die cavity, and formed punch (5) is located in the die cavity, and formed punch (5) outer wall is equipped with the sealing structure being circular layout, sheath (6) be set in formed punch (5) it is external and can vertical sliding be mounted on mounting base (4), formed and managed between sheath (6) and formed punch (5) Holding tank is held, the formed punch (5) of at least one pipe end mounting assembly is equipped with liquid injection hole;
Pressure sensor (2) is arranged on the formed punch (5) of at least one pipe end mounting assembly, and pressure sensor (2) is for detecting Tubing internal pressure, displacement sensor (3) are located at tubing installation position side for detecting the deformational displacement of outer pipe wall.
2. the Measurement die of tube forming limiting figure according to claim 1, which is characterized in that sheath (6) inner wall is equipped with Anti-slip part.
3. the Measurement die of tube forming limiting figure according to claim 1, which is characterized in that formed punch (5) has vertical The column structure of extension.
4. the Measurement die of tube forming limiting figure according to claim 1, which is characterized in that sheath (6) is close to described Tubing installation position one end inner edge is equipped with annular guide surface, in the annular guide surface radially adjacent to tubing installation position one end by It is cumulative big.
5. the Measurement die of tube forming limiting figure according to claim 1, which is characterized in that two pipe end mounting assemblies Respectively upper pipe end mounting assembly and lower pipe end mounting assembly, upper pipe end mounting assembly include upper mounting seat, upper punch and upper shield Set, lower pipe end mounting assembly include lower mounting seat, low punch and lower jacket, and on the lower punch, pressure passes for the liquid injection hole setting Sensor (2) is arranged on upper punch.
6. the Measurement die of tube forming limiting figure according to claim 5, which is characterized in that upper punch and low punch tool There is the column structure being vertically arranged and the two is coaxially arranged.
7. the Measurement die of tube forming limiting figure according to claim 1, which is characterized in that further include booster, increase Depressor is connected to the liquid injection hole.
8. the Measurement die of tube forming limiting figure according to claim 1, which is characterized in that formed punch (5) and sheath (6) It is removably mounted on mounting base (4).
CN201811427002.3A 2018-11-27 2018-11-27 A kind of Measurement die of tube forming limiting figure Pending CN109596432A (en)

Priority Applications (1)

Application Number Priority Date Filing Date Title
CN201811427002.3A CN109596432A (en) 2018-11-27 2018-11-27 A kind of Measurement die of tube forming limiting figure

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
CN201811427002.3A CN109596432A (en) 2018-11-27 2018-11-27 A kind of Measurement die of tube forming limiting figure

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CN109596432A true CN109596432A (en) 2019-04-09

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113654904A (en) * 2017-06-20 2021-11-16 威尔德尔格管道科技有限公司 Pipe testing method and apparatus
WO2022101605A1 (en) * 2020-11-10 2022-05-19 Verderg Pipe Technology Limited A pipe testing apparatus and method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005046904A1 (en) * 2003-10-25 2005-05-26 Eisen- Und Metallwerke Ferndorf Gmbh Method for adjusting specific quality characteristics and properties of pipes by means of a pressure test
WO2008114049A2 (en) * 2007-03-20 2008-09-25 Verderg Ltd Method and apparatus for pipe testing
CN103272910A (en) * 2013-05-20 2013-09-04 哈尔滨工业大学 Tubular product hydraulic forming device capable of achieving inside and outside pressurization
CN103712862A (en) * 2013-12-30 2014-04-09 重庆市科学技术研究院 Device for testing expansion performance of magnesium alloy tubular product
CN104634665A (en) * 2014-09-12 2015-05-20 北京航空航天大学 Pipe liquid filling bulging test method and device

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
WO2005046904A1 (en) * 2003-10-25 2005-05-26 Eisen- Und Metallwerke Ferndorf Gmbh Method for adjusting specific quality characteristics and properties of pipes by means of a pressure test
WO2008114049A2 (en) * 2007-03-20 2008-09-25 Verderg Ltd Method and apparatus for pipe testing
CN103272910A (en) * 2013-05-20 2013-09-04 哈尔滨工业大学 Tubular product hydraulic forming device capable of achieving inside and outside pressurization
CN103712862A (en) * 2013-12-30 2014-04-09 重庆市科学技术研究院 Device for testing expansion performance of magnesium alloy tubular product
CN104634665A (en) * 2014-09-12 2015-05-20 北京航空航天大学 Pipe liquid filling bulging test method and device

Non-Patent Citations (1)

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Title
程鹏志 等: "力约束管材自由胀形试验研究与材料性能测试", 《北京航空航天大学学报》 *

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN113654904A (en) * 2017-06-20 2021-11-16 威尔德尔格管道科技有限公司 Pipe testing method and apparatus
WO2022101605A1 (en) * 2020-11-10 2022-05-19 Verderg Pipe Technology Limited A pipe testing apparatus and method

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Application publication date: 20190409