CN102189189A - High-precision thermal expanding method for high-strength steel pipes - Google Patents

High-precision thermal expanding method for high-strength steel pipes Download PDF

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Publication number
CN102189189A
CN102189189A CN 201110095139 CN201110095139A CN102189189A CN 102189189 A CN102189189 A CN 102189189A CN 201110095139 CN201110095139 CN 201110095139 CN 201110095139 A CN201110095139 A CN 201110095139A CN 102189189 A CN102189189 A CN 102189189A
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steel pipe
steel pipes
outer module
expanding
expanding machine
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CN102189189B (en
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王振生
王占理
李书华
李厚明
王德清
李显明
陈佳
蒙家才
彭德平
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Xiangtan Huajin Heavy Equipment Technology Co.,Ltd.
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XIANGTAN HUAJIN TECHNOLOGY Co Ltd
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Abstract

The invention discloses a high-precision thermal expanding method for high-strength steel pipes. The method comprises the processing steps of preparation of an expanding machine, furnace heating, thermal expanding, external furnace cooling and stripping. The steel pipes to be expanded are charged into a heating furnace and heated to the temperature of between 600 and 800 DEG C, wherein according to the steel pipes, the tensile strength sigma b is between 1,640 and 2,100MPa, the yielding strength sigma 0.2 is 1,400 to 1,950MPa, the wall thickness is 1 to 10 millimeters, the steel pipes are made of different materials, and the inside diameters of the steel pipes are conical or cylindrical; after expanding, the steel pipes are processed into the high-precision steel pipes, the roundness of which is less than or equal to 0.4 millimeter and the linearity of which is less than or equal to 0.6 millimeters per meter; and the method overcomes the defect that the normal temperature expanding process cannot meet the high-precision expanding requirements of the high-strength steel pipes. The method is suitable for expanding various high-strength steel pipes with different chemical components. The expanded high-strength steel pipes produced by using the method are widely applied in the fields of petroleum and natural gas delivery, aerospace and military affairs.

Description

The high accuracy thermal expansion method of high tensile steel tube
Technical field
The present invention relates to the hot-working field, be specifically related to a kind of high accuracy thermal expansion method of high tensile steel tube.
Background technology
Expanding machine is mainly used in the hole enlargement school shape and the destressing of the ERW of transfer oil, natural gas at normal temperatures.Along with the arrival of China's thing, north and south oil gas big link, submerged pipeline, ore pulp pipeline upsurge in construction, the hole enlargement technology obtains the utmost point as one of operation important in the ERW production and uses widely.Yet other improves along with the steel tubing quality and grade, the increase, particularly Aero-Space of steel pipe thickness and military field be to σ under the room temperature condition b〉=1640MPa, σ 0.2The hole enlargement of the superstrength alloy steel steel pipe of 〉=1400MPa, the normal temperature expanding technology can not satisfy instructions for use.And Aero-Space and military field are also very strict to the required precision of steel pipe, and the normal temperature expanding technology more can not meet the demands.
Summary of the invention
In order to solve the problems of the technologies described above, to the invention provides a kind of use expanding machine and heating furnace and carry out hot-working, the high accuracy thermal expansion method of the high tensile steel tube that procedure of processing is succinct.
The technical scheme that the present invention solves the problems of the technologies described above is: a kind of high accuracy thermal expansion method of high tensile steel tube, and its procedure of processing is:
(1), prepare expanding machine: the graphite spraying emulsion is as lubricant and parting compound on the outer module of expanding machine, and outer module is made by GH4500 material or GH2135 material;
(2), heating in the stove: with tensile strength sigma bBe 1640MPa~2100MPa, yield strength σ 0.2For 1400MPa~1950MPa and wall thickness 1mm~10mm treat the hole enlargement steel pipe heating furnace of packing into, in heating furnace, charge into argon gas then, then with Medium frequency induction coil Fast Heating steel pipe to 600 ℃~800 ℃, and under this temperature, be incubated 1~3 minute;
(3), thermal expansion: open Compaction of Heating Furnace Door, with expanding machine reach, the outer module of the expanding machine that has sprayed the graphite emulsion is inserted the steel pipe inner chamber, the operation expanding machine makes outer module motion and pushes the steel pipe inwall, and the steel pipe type that rises carries out thermal expansion;
(4), stove cools off outward: outer module rises after the type hole enlargement, expanding machine retreats, and the state when outer module keeps rising by the type hole enlargement withdraws from from heating furnace with steel pipe, outer module is with the steel pipe air cooling, and the type hole enlargement state that rises in process air cooler between outer module of maintenance and the steel pipe;
(5), the demoulding: to normal temperature, the operation expanding machine makes outer module withdrawal to outer module with the steel pipe air cooling, break away from steel pipe, the graphite emulsion has guaranteed the smooth demoulding of steel pipe as lubricant and parting compound, precision behind the pipe expanding is: circularity≤0.4mm, linearity≤0.6mm/m.
Technical scheme of the present invention has overcome the defective that high accuracy hole enlargement that the normal temperature expanding technology can not satisfy high tensile steel tube requires.
The beneficial effect that the present invention is produced compared to existing technology:
1, the present invention has obviously improved the circularity and the linearity of steel pipe, has reached high-precision requirement.
2, the tensile strength sigma of the high tensile steel tube of the present invention's energy hole enlargement bBe 1640 MPa~2100MPa, yield strength σ 0.2Be 1400MPa~1950MPa, wall thickness 1mm~10mm has opened up the new range of application of hole enlargement high tensile steel tube.
3, the present invention can be the high tensile steel tube hole enlargement of band tapering, has increased the scope of application of band tapering steel pipe.
4, the high strength after the hole enlargement, high precision steel tube are in Aero-Space and military field, and oil and natural gas conveying aspect all will play an important role.
5, diameter enlarging method of the present invention is succinctly practical, and processing cost is low.
The present invention is applicable to the hole enlargement of the various high tensile steel tubes that chemical composition is different.
Below in conjunction with the drawings and specific embodiments the present invention is described in further detail.
Description of drawings
Fig. 1 is a functional-block diagram of the present invention.
Fig. 2 is that illustration is implemented in the hole enlargement of the high tensile steel tube of 4 kinds of unlike materials of the present invention.
The specific embodiment
Referring to accompanying drawing 1, a kind of high accuracy thermal expansion method of high tensile steel tube, its procedure of processing is:
(1), prepares expanding machine: become emulsion state with running water dilution graphite, the graphite emulsion is packed in the fluid reservoir of spray gun, spray gun connects the compressed air of 0.3~0.6 MPa, with the automatic or manual spray gun vaporific spraying is carried out on the outer module surface of expanding machine, gun traffic is 40~60 milliliters/second; The graphite spraying emulsion is as lubricant and parting compound on the outer module of expanding machine, and outer module is by GH 4500 materials or GH 2135 material manufacturings.The expanding machine setting in orbit, and is convenient mobile.
(2), heating in the stove: with tensile strength sigma bBe 1640~2100 MPa, yield strength σ 0.2Be 1400 MPa~1950 MPa, wall thickness is 1mm~10mm, circularity≤5.0mm, linearity≤3.0mm/m treats the hole enlargement steel pipe heating furnace of packing into, in heating furnace, charge into argon gas then, kept 5~10 minutes, then with Medium frequency induction coil Fast Heating steel pipe to 600 ℃~800 ℃, and under this temperature, be incubated 1~3 minute, the steel pipe in the heating furnace is heated evenly.Charge into argon gas in the heating furnace, reduced the air concentration in the heating furnace, the oxidation that has taken place when having reduced the steel pipe heating.
(3), thermal expansion: open Compaction of Heating Furnace Door, with expanding machine reach, the outer module of the expanding machine that has sprayed the graphite emulsion is inserted the steel pipe inner chamber, the operation expanding machine makes outer module motion and pushes the steel pipe inwall, and the steel pipe type that rises carries out thermal expansion.When thermal expansion, the graphite emulsion is as lubricant, steel pipe and outside form one deck coating between the module, prevent between steel pipe and the outer module that generation weares and teares and cohere.
(4), stove cools off outward: outer module rises after the type hole enlargement, expanding machine retreats, and the state when outer module keeps rising by the type hole enlargement withdraws from from heating furnace with steel pipe, outer module is with the steel pipe air cooling, and the type hole enlargement state that rises in process air cooler between outer module of maintenance and the steel pipe.In the pressurize during to normal temperature of steel pipe air cooling, hole enlargement place can be out of shape.
(5), the demoulding: to normal temperature, the operation expanding machine makes outer module withdrawal to outer module with the steel pipe air cooling, break away from steel pipe, the graphite emulsion has guaranteed the smooth demoulding of steel pipe as lubricant and parting compound, precision behind the pipe expanding is: circularity≤0.4mm, linearity≤0.6mm/m; Then transport the steel pipe of finishing hole enlargement with the adapter dolly.
Embodiment 1 adopts the steel pipe of T250 material, the mechanical property of material: tensile strength sigma bBe 1700MPa, yield strength
σ 0.2Be 1600MPa, wall thickness is 5mm, pipe diameter φ 395.7mm, length 970mm, circularity≤4.6mm, linearity≤2.6mm/m.
Manual spray gun is to the even graphite spraying emulsion in the outer module of expanding machine surface; Send the pipe dolly that steel pipe is sent into heating furnace, applying argon gas is after 10 minutes, and the 2500Hz heating in medium frequency to 200 ℃, be incubated 5 minutes, impurity such as removal water vapour and greasy dirt in the room temperature heating 3 minutes.Quickly heated up to 700 ℃ in 4~6 minutes, be incubated and stop heating after 2 minutes, open movable Compaction of Heating Furnace Door, heating furnace will be moved up into before the expanding machine, outer module is inserted steel pipe, and the type that rises expands internal diameter to φ 398mm, and then outer module keeps rising type hole enlargement steel pipe state, withdraw from from heating furnace together, air cooling is to normal temperature.Then outer module withdrawal breaks away from steel pipe, adopts roller type to take over dolly and is sent from.After testing, behind the T250 pipe expanding, pipe diameter is φ 397.8mm, and enlarging rate is 0.53%, circularity≤0.4mm, linearity≤0.6mm/m.
Embodiment 2 adopts the conical steel pipe of T300 material, the mechanical property of material: tensile strength sigma bBe 2100 MPa, yield strength σ 0.2Be 1900 MPa, wall thickness is 4 mm, the conical steel pipe internal diameter size: microcephaly φ 393.1mm, major part φ 430.1mm, length 940mm, circularity≤4.3mm, linearity≤2.8mm/m.
The external module of manual spray gun surface graphite spraying emulsion; Send the pipe dolly that steel pipe is sent into heating furnace, applying argon gas is after 10 minutes, and 3000 Hz heating in medium frequency to 200 ℃, be incubateds 4 minutes in the room temperature heating 2 minutes, remove impurity such as water vapour and greasy dirt, quickly heat up to 800 ℃ in 5~6 minutes, are incubated 2 minutes, stop to heat.Open movable Compaction of Heating Furnace Door, move up into heating furnace before the expanding machine after, outer module is inserted steel pipe, the type that rises expands internal diameter to microcephaly φ 395.4mm, major part φ 432.4mm, outer module keeps rising type hole enlargement steel pipe state, withdraws from from heating furnace together, air cooling is to normal temperature.Outer module withdrawal is separated from steel pipe, adopts roller type to take over dolly and is sent from.After testing, internal diameter is microcephaly φ 395.1mm after the hole enlargement of T300 conical steel pipe, and major part φ 432.1mm, enlarging rate are 0.47 ~ 0.51%, circularity≤0.4mm, linearity≤0.6mm/m.
Embodiment 3 adopts the conical steel pipe of 16Co14Ni10Cr2Mo material, material mechanical property: tensile strength sigma bBe 1749 MPa, yield strength σ 0.2Be 1598 MPa, wall thickness 8 mm, pipe diameter size: microcephaly φ 420.2mm, major part φ 455.3mm, length 940mm, circularity≤5.0mm, linearity≤3.0mm/m.
The external module of manual spray gun surface graphite spraying breast; Send the pipe dolly that steel pipe is sent into heating furnace, applying argon gas is after 10 minutes, and 2000 Hz heating in medium frequency to 200 ℃, be incubateds 8 minutes, impurity such as removal water vapour and greasy dirt in the room temperature heating 4 minutes.Quickly heat up to 750 ℃ in 7 minutes, be incubated 2 minutes, stop heating.Open movable Compaction of Heating Furnace Door, move up into heating furnace before the expanding machine after, outer module is inserted steel pipe, the type that rises expands internal diameter to microcephaly φ 423mm, major part φ 458.1mm.Outer module keeps rising type hole enlargement steel pipe state, withdraws from from heating furnace together, and air cooling is to normal temperature and pressurize.Outer module withdrawal is separated from steel pipe, adopts roller type to take over dolly and is sent from.After testing, internal diameter is after the conical steel pipe hole enlargement of 16Co14Ni10Cr2Mo: microcephaly φ 422.8mm, major part φ 457.8mm, enlarging rate are 0.55 ~ 0.62%, circularity≤0.4mm, linearity≤0.6mm/m.
Referring to Fig. 2, Fig. 2 is that illustration is implemented in the hole enlargement of the high tensile steel tube of 4 kinds of unlike materials of the present invention, and the material of steel pipe is respectively 18Ni (200), 18Ni (250), 18Ni (300) and G99, their tensile strength sigma bBetween 1640MPa~2100MPa, yield strength σ 0.2Between 1400MPa~1950MPa, wall thickness is in 1mm~10mm scope, and after testing, they have all reached circularity≤0.4mm, the high-precision requirement of linearity≤0.6mm/m after hole enlargement.

Claims (1)

1. the high accuracy thermal expansion method of a high tensile steel tube, it is characterized in that: its procedure of processing is:
(1), prepare expanding machine: the graphite spraying emulsion is as lubricant and parting compound on the outer module of expanding machine, and outer module is made by GH4500 material or GH2135 material;
(2), heating in the stove: with tensile strength sigma bBe 1640MPa~2100MPa, yield strength σ 0.2For 1400MPa~1950MPa and wall thickness 1mm~10mm treat the hole enlargement steel pipe heating furnace of packing into, in heating furnace, charge into argon gas then, then with Medium frequency induction coil Fast Heating steel pipe to 600 ℃~800 ℃, and under this temperature, be incubated 1~3 minute;
(3), thermal expansion: open Compaction of Heating Furnace Door, with expanding machine reach, the outer module of the expanding machine that has sprayed the graphite emulsion is inserted the steel pipe inner chamber, the operation expanding machine makes outer module motion and pushes the steel pipe inwall, and the steel pipe type that rises carries out thermal expansion;
(4), stove cools off outward: outer module rises after the type hole enlargement, expanding machine retreats, and the state when outer module keeps rising by the type hole enlargement withdraws from from heating furnace with steel pipe, outer module is with the steel pipe air cooling, and the type state that rises in process air cooler between outer module of maintenance and the steel pipe;
(5), the demoulding: to normal temperature, the operation expanding machine makes outer module withdrawal to outer module with the steel pipe air cooling, break away from steel pipe, the graphite emulsion has guaranteed the smooth demoulding of steel pipe as lubricant and parting compound, precision behind the pipe expanding is: circularity≤0.4mm, linearity≤0.6mm/m.
CN 201110095139 2011-04-15 2011-04-15 High-precision thermal expanding method for high-strength steel pipes Active CN102189189B (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102489593A (en) * 2011-11-24 2012-06-13 贵州安大航空锻造有限责任公司 Hot bulge forming method for aluminum-alloy flash buttwelding ring components
CN102489598A (en) * 2011-11-24 2012-06-13 贵州安大航空锻造有限责任公司 Thermal bulging process for special-shaped bearing steel rolled ring workpieces
CN102489597A (en) * 2011-11-24 2012-06-13 贵州安大航空锻造有限责任公司 Hot bulging method for rectangular bearing steel rolled ring
CN104550516A (en) * 2014-12-15 2015-04-29 南京航空航天大学 Steel pipe cold diameter expanding straightening method

Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62156031A (en) * 1985-12-26 1987-07-11 Kawasaki Steel Corp Production of metallic tube having connection part
CN1248501A (en) * 1999-07-23 2000-03-29 广州南方管道有限公司 Process for expanding end of large diameter thick wall steel pipe
CN1954933A (en) * 2005-10-26 2007-05-02 竭国忠 Equipment and method for manufacturing metal large diameter equal wall thickness slit elbow and expanding tube by thermal push
CN101468364A (en) * 2007-12-29 2009-07-01 付朋 Thermal expansion machine for producing stainless steel tube
CN101631402A (en) * 2009-07-25 2010-01-20 衡阳鸿大特种钢管有限公司 Multi-section medium frequency heating method for pipe expanding set and device thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPS62156031A (en) * 1985-12-26 1987-07-11 Kawasaki Steel Corp Production of metallic tube having connection part
CN1248501A (en) * 1999-07-23 2000-03-29 广州南方管道有限公司 Process for expanding end of large diameter thick wall steel pipe
CN1954933A (en) * 2005-10-26 2007-05-02 竭国忠 Equipment and method for manufacturing metal large diameter equal wall thickness slit elbow and expanding tube by thermal push
CN101468364A (en) * 2007-12-29 2009-07-01 付朋 Thermal expansion machine for producing stainless steel tube
CN101631402A (en) * 2009-07-25 2010-01-20 衡阳鸿大特种钢管有限公司 Multi-section medium frequency heating method for pipe expanding set and device thereof

Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN102489593A (en) * 2011-11-24 2012-06-13 贵州安大航空锻造有限责任公司 Hot bulge forming method for aluminum-alloy flash buttwelding ring components
CN102489598A (en) * 2011-11-24 2012-06-13 贵州安大航空锻造有限责任公司 Thermal bulging process for special-shaped bearing steel rolled ring workpieces
CN102489597A (en) * 2011-11-24 2012-06-13 贵州安大航空锻造有限责任公司 Hot bulging method for rectangular bearing steel rolled ring
CN102489597B (en) * 2011-11-24 2014-04-02 贵州安大航空锻造有限责任公司 Hot bulging method for rectangular bearing steel rolled ring
CN102489593B (en) * 2011-11-24 2014-04-02 贵州安大航空锻造有限责任公司 Hot bulge forming method for aluminum-alloy flash buttwelding ring components
CN102489598B (en) * 2011-11-24 2014-04-02 贵州安大航空锻造有限责任公司 Thermal bulging process for special-shaped bearing steel rolled ring workpieces
CN104550516A (en) * 2014-12-15 2015-04-29 南京航空航天大学 Steel pipe cold diameter expanding straightening method
CN104550516B (en) * 2014-12-15 2016-07-06 南京航空航天大学 The cold expanding method for aligning of steel pipe

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