CN110906069B - Manufacturing method of vacuum mechanical composite pipe - Google Patents

Manufacturing method of vacuum mechanical composite pipe Download PDF

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Publication number
CN110906069B
CN110906069B CN201911156966.3A CN201911156966A CN110906069B CN 110906069 B CN110906069 B CN 110906069B CN 201911156966 A CN201911156966 A CN 201911156966A CN 110906069 B CN110906069 B CN 110906069B
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pipe
wall
vacuum
mechanical composite
inner pipe
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CN110906069A (en
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杜卫锋
文书林
魏帆
王斌
孙彦青
孙嘉悦
赵敏
朱烨
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Xian Sunward Aerospace Material Co Ltd
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Xian Sunward Aerospace Material Co Ltd
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    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
    • F16L—PIPES; JOINTS OR FITTINGS FOR PIPES; SUPPORTS FOR PIPES, CABLES OR PROTECTIVE TUBING; MEANS FOR THERMAL INSULATION IN GENERAL
    • F16L9/00—Rigid pipes
    • F16L9/18—Double-walled pipes; Multi-channel pipes or pipe assemblies

Abstract

The invention discloses a method for manufacturing a vacuum mechanical composite pipe, which comprises the following steps of (1) sleeving an outer pipe on the outer wall of an inner pipe, wherein the end part of the outer pipe is formed between the end part of the outer pipe and the outer wall of the inner pipe; (2) sealing the pipe end, and carrying out vacuum treatment on a gap formed between the pipe end and the outer wall of the inner pipe and the inner wall of the outer pipe; (3) after the required vacuum degree between the outer pipe and the inner pipe is achieved, an inner supporting device is adopted to pressurize the inner wall of the inner pipe close to the pipe end until the outer wall of the inner pipe is tightly attached to the inner wall of the outer pipe, and the pipe end is sealed and welded; (4) mechanically compounding the inner pipe and the outer pipe processed in the step 3 to obtain a vacuum mechanical composite pipe; (5) and eliminating the residual stress of the vacuum mechanical composite pipe. The invention has the beneficial effects that: the anti-bulging capacity of the composite tube is improved by adopting a method of eliminating residual stress through vacuum treatment and a vibration method, the problem of inner tube bulging instability is solved, and the service life of the mechanical composite tube is prolonged.

Description

Manufacturing method of vacuum mechanical composite pipe
Technical Field
The invention belongs to the technical field of composite tube manufacturing, and particularly relates to a manufacturing method of a vacuum mechanical composite tube.
Background
The mechanical composite pipe is a composite structure which is mechanically jointed by pipelines made of two or more different materials through mechanical processing, wherein metallurgical bonding is not formed between the interfaces of the inner pipe and the outer pipe, but the mechanical jointing is realized by the residual stress of the interfaces. The inner tube of the mechanical composite tube does not bear pressure and only has the corrosion resistance, so the wall thickness of the inner tube is generally between 1mm and 3mm, the mechanical composite tube belongs to a thin-walled tube, and the mechanical composite tube is known by material mechanics to have small in-plane rigidity for the thin-walled tube with a large diameter-thickness ratio, and easily generate the phenomena of bulging instability and the like in the processing and using processes.
At present, as the mechanical composite pipe is changed from a small caliber to a large caliber and is developed from a low-temperature use environment to a high-temperature use environment, the phenomenon of bulging and instability of the inner pipe of the mechanical composite pipe is increased continuously. At present, no good solution is provided for the problem of instability of the mechanical composite pipe inner tube bulging at home and abroad.
Disclosure of Invention
The invention aims to provide a manufacturing method of a vacuum mechanical composite pipe, which solves the problem of instability of a bulge of the mechanical composite pipe in the prior art.
The invention adopts the technical scheme that the manufacturing method of the vacuum mechanical composite pipe comprises the following steps:
step 1, sleeving an outer pipe (2) on the outer wall of an inner pipe (1), and forming a pipe end (7) between the end part of the outer pipe (2) and the outer wall of the inner pipe (1);
step 2, sealing the pipe end (7) by adopting a sealing device (4), and carrying out vacuum treatment on a gap formed between the pipe end (7) and the outer wall of the inner pipe (1) and the inner wall of the outer pipe (2);
step 3, after the required vacuum degree between the outer pipe (2) and the inner pipe (1) is achieved, the inner wall of the inner pipe (1) of the pipe end (7) is pressurized until the outer wall of the inner pipe (1) is tightly attached to the inner wall of the outer pipe (2), the sealing device (4) is removed, and the pipe end (7) is sealed and welded;
step 4, mechanically compounding the inner pipe (1) and the outer pipe (2) processed in the step 3 to obtain a vacuum mechanical composite pipe;
and 5, eliminating the residual stress of the vacuum mechanical composite pipe.
The invention is also characterized in that:
in the step 2, the sealing device (4) is a rubber sleeve, wherein a suction nozzle (5) is arranged on the rubber sleeve on one side, and a gap formed between the pipe end (7) and the outer wall of the inner pipe (1) and the inner wall of the outer pipe (2) is subjected to vacuum treatment from the suction nozzle (5) until the vacuum degree is less than or equal to-0.08 MPa.
Step 3 is specifically implemented according to the following steps:
when the vacuum degree between the outer pipe (2) and the inner pipe (1) is less than or equal to-0.08 MPa, an inner supporting device (3) is adopted to pressurize the inner wall of the inner pipe (1) of the pipe end (7), so that the outer wall of the inner pipe (1) is tightly attached to the inner wall of the outer pipe (2), the distance between the inner supporting device (3) and the pipe end (7) is 50-100 mm, the applied pressure P is 1.5 x (2t sigma)/D, and in the formula, t is the thickness of the inner pipe wall and mm; σ is the yield strength of the inner tube, MPa; d is the outer diameter of the inner pipe, mm, the sealing device (4) is removed, and the pipe end (7) is sealed and welded.
In the step 4, the compounding mode of the inner pipe (1) and the outer pipe (2) is one of hydraulic compounding, deflagration compounding and spinning compounding.
And 5, eliminating the residual stress of the vacuum mechanical composite tube by adopting the first three-order vibration frequency of the vacuum mechanical composite tube.
The vibration time of the vacuum mechanical composite tube is 5-10 min.
The invention has the beneficial effects that: the anti-bulging capacity of the composite tube is improved by adopting a vacuumizing method, and the problem of inner tube bulging instability is solved; and the residual stress of the composite pipe is eliminated by adopting a vibration method, and the service life of the mechanical composite pipe is prolonged.
Drawings
FIG. 1 is a schematic structural diagram of a vacuum mechanical composite tube in a method for manufacturing the vacuum mechanical composite tube according to the present invention;
fig. 2 is a view of an intermediate process of manufacturing a vacuum mechanical composite tube in the method of manufacturing a vacuum mechanical composite tube according to the present invention.
In the figure, 1 is an inner pipe, 2 is an outer pipe, 3 is an inner support device, 4 is a rubber sleeve, 5 is an air suction nozzle, 6 is a vacuum meter, and 7 is a pipe end.
Detailed Description
The present invention will be described in detail below with reference to the accompanying drawings and specific embodiments.
Through the mechanism analysis to mechanical type compound pipe inner tube swell, the load that leads to the inner tube to take place to swell unstability in mechanical type compound pipe processing and use has two kinds: firstly, the gas pressure between the inner pipe and the outer pipe is remained after sealing and welding; and the residual stress of the inner pipe after compounding.
The vacuum degree of the mechanical composite pipe is ensured by a vacuum pumping method, and for the composite pipe manufactured by vacuum pumping between an inner pipe and an outer pipe, the vacuum degree between the inner pipe and the outer pipe is required to be less than or equal to-0.08 MPa; and eliminating the residual stress of the composite pipe by adopting a vibration method.
The invention relates to a method for manufacturing a vacuum mechanical composite pipe, which is implemented according to the following steps when the inner pipe diameter-thickness ratio is less than 150:
step 1, sleeving an outer pipe 2 on the outer wall of an inner pipe 1, and forming a pipe end 7 between the end part of the outer pipe 2 and the outer wall of the inner pipe 1;
step 2, sealing the pipe end 7 by adopting a rubber sleeve, arranging an air suction nozzle 5 on the rubber sleeve on one side, and carrying out vacuum treatment on a gap formed between the pipe end 7 and the outer wall of the inner pipe 1 and the inner wall of the outer pipe 2 from the air suction nozzle 5 until the vacuum degree is less than or equal to-0.08 MPa;
step 3, after the vacuum degree between the outer pipe 2 and the inner pipe 1 is less than or equal to-0.08 MPa, pressurizing the inner wall of the inner pipe 1 close to the pipe section by using an inner supporting device 3, so that the outer wall of the inner pipe 1 is tightly attached to the inner wall of the outer pipe 2, the distance between the inner supporting device 3 and the pipe end 7 is 50-100 mm, and the applied pressure P is 1.5 x (2t sigma)/D, wherein t is the thickness of the inner pipe wall and mm; σ is the yield strength of the inner tube, MPa; d is the outer diameter of the inner pipe, mm, the rubber sleeve is removed, and the pipe end 7 is sealed and welded;
step 4, mechanically compounding the inner pipe 1 and the outer pipe 2 processed in the step 3 in one of hydraulic compounding, deflagration compounding and spinning compounding modes to obtain a vacuum mechanical composite pipe;
and 5, placing the vacuum mechanical composite tube on a vibration table, determining the vibration frequency of the vacuum mechanical composite tube by adopting a frequency scanning method, and vibrating for 5-10 min by adopting the first three-order vibration frequency of the vacuum mechanical composite tube to eliminate the residual stress of the vacuum mechanical composite tube.
The vacuum degree between the inner pipe 1 and the outer pipe 2 of the vacuum mechanical composite pipe is detected to verify the improvement of the anti-bulging capacity of the composite pipe by sealing welding after vacuumizing:
and (3) installing a vacuum meter 6 at one end far away from the air suction nozzle 5 in the step (1), wherein the installation position is a position which is less than 500mm away from the rubber sleeve at the end as shown in figure 2, if the reading on the vacuum meter is less than or equal to-0.08 MPa after the step (5), the vacuum mechanical composite pipe is qualified, otherwise, the vacuum force is improved, and the vacuum mechanical composite pipe is manufactured according to the steps (1) to (5) until the vacuum degree is less than or equal to-0.08 MPa.
Example 1
Step 1, sleeving an outer pipe 2 on the outer wall of an inner pipe 1, and forming a pipe end 7 between the end part of the outer pipe 2 and the outer wall of the inner pipe 1;
step 2, sealing the pipe end 7 by using a rubber sleeve, arranging an air suction nozzle 5 on the rubber sleeve on one side, and carrying out vacuum treatment on a gap formed between the pipe end 7 and the outer wall of the inner pipe 1 and the inner wall of the outer pipe 2 from the air suction nozzle 5 until the vacuum degree is-0.05 MPa;
step 3, pressurizing the inner wall of the inner pipe 1 close to the pipe section by using an inner support device 3, so that the outer wall of the inner pipe 1 is tightly attached to the inner wall of the outer pipe 2, wherein the distance between the inner support device 3 and the pipe end 7 is 50mm, and the applied pressure P is 1.5 x (2t sigma)/D, wherein t is the thickness of the inner pipe wall and mm; σ is the yield strength of the inner tube, MPa; d is the outer diameter of the inner pipe, mm, the rubber sleeve is removed, and the pipe end 7 is sealed and welded;
step 4, mechanically compounding the inner pipe 1 and the outer pipe 2 processed in the step 3 in a hydraulic compounding mode to obtain a vacuum mechanical compound pipe;
and 5, placing the vacuum mechanical composite tube on a vibration table, determining the vibration frequency of the vacuum mechanical composite tube by adopting a frequency scanning method, and vibrating for 5min by adopting the first three-order vibration frequency of the vacuum mechanical composite tube to eliminate the residual stress of the vacuum mechanical composite tube.
Detecting the vacuum degree between the inner pipe 1 and the outer pipe 2 of the vacuum mechanical composite pipe:
in the step 1, a vacuum meter 6 is arranged at the end far away from the air suction nozzle 5, the installation position is 450mm away from the rubber sleeve at the end, and as shown in figure 2, the reading on the vacuum meter 6 is-0.06 MPa after the step 5.
Example 2
Step 1, sleeving an outer pipe 2 on the outer wall of an inner pipe 1, and forming a pipe end 7 between the end part of the outer pipe 2 and the outer wall of the inner pipe 1;
step 2, sealing the pipe end 7 by using a rubber sleeve, arranging an air suction nozzle 5 on the rubber sleeve on one side, and carrying out vacuum treatment on a gap formed between the pipe end 7 and the outer wall of the inner pipe 1 and the inner wall of the outer pipe 2 from the air suction nozzle 5 until the vacuum degree is 0.07 MPa;
step 3, pressurizing the inner wall of the inner pipe 1 close to the pipe section by using an inner support device 3, so that the outer wall of the inner pipe 1 is tightly attached to the inner wall of the outer pipe 2, wherein the distance between the inner support device 3 and the pipe end 7 is 75mm, and the applied pressure P is 1.5 x (2t sigma)/D, wherein t is the thickness of the inner pipe wall and mm; σ is the yield strength of the inner tube, MPa; d is the outer diameter of the inner pipe, mm, the rubber sleeve is removed, and the pipe end 7 is sealed and welded;
step 4, mechanically compounding the inner pipe 1 and the outer pipe 2 processed in the step 3 in a hydraulic compounding mode to obtain a vacuum mechanical compound pipe;
and 5, placing the vacuum mechanical composite tube on a vibration table, determining the vibration frequency of the vacuum mechanical composite tube by adopting a frequency scanning method, and vibrating for 7min by adopting the first three-order vibration frequency of the vacuum mechanical composite tube to eliminate the residual stress of the vacuum mechanical composite tube.
Detecting the vacuum degree between the inner pipe 1 and the outer pipe 2 of the vacuum mechanical composite pipe:
in the step 1, a vacuum meter 6 is arranged at the end far away from the air suction nozzle 5, the installation position is 450mm away from the rubber sleeve at the end, and as shown in figure 2, the reading on the vacuum meter 6 is-0.07 MPa after the step 5.
Example 3
Step 1, sleeving an outer pipe 2 on the outer wall of an inner pipe 1, and forming a pipe end 7 between the end part of the outer pipe 2 and the outer wall of the inner pipe 1;
step 2, sealing the pipe end 7 by using a rubber sleeve 4, arranging an air suction nozzle 5 on the rubber sleeve 4 on one side, and carrying out vacuum treatment on a gap formed between the pipe end 7 and the outer wall of the inner pipe 1 and the inner wall of the outer pipe 2 from the air suction nozzle 5 until the vacuum degree is 0.08 MPa;
step 3, pressurizing the inner wall of the inner pipe 1 close to the pipe section by using an inner support device 3, so that the outer wall of the inner pipe 1 is tightly attached to the inner wall of the outer pipe 2, wherein the distance between the inner support device 3 and the pipe end 7 is 100mm, and the applied pressure P is 1.5 x (2t sigma)/D, wherein t is the thickness of the inner pipe wall and mm; σ is the yield strength of the inner tube, MPa; d is the outer diameter of the inner pipe, mm, the rubber sleeve 4 is removed, and the pipe end 7 is sealed and welded;
step 4, mechanically compounding the inner pipe 1 and the outer pipe 2 processed in the step 3 in a hydraulic compounding mode to obtain a vacuum mechanical compound pipe;
and 5, placing the vacuum mechanical composite tube on a vibration table, determining the vibration frequency of the vacuum mechanical composite tube by adopting a frequency scanning method, and vibrating for 10min by adopting the first three-order vibration frequency of the vacuum mechanical composite tube to eliminate the residual stress of the vacuum mechanical composite tube.
Detecting the vacuum degree between the inner pipe 1 and the outer pipe 2 of the vacuum mechanical composite pipe:
in the step 1, a vacuum meter 6 is arranged at the end far away from the air suction nozzle 5, the installation position is 450mm away from the rubber sleeve at the end, and as shown in figure 2, the reading on the vacuum meter 6 is-0.08 MPa after the step 5.

Claims (4)

1. A manufacturing method of a vacuum mechanical composite pipe is characterized by comprising the following steps:
step 1, sleeving an outer pipe (2) on the outer wall of an inner pipe (1), and forming a pipe end (7) between the end part of the outer pipe (2) and the outer wall of the inner pipe (1);
step 2, sealing the pipe end (7) by adopting a sealing device (4), and carrying out vacuum treatment on a gap formed between the pipe end (7) and the outer wall of the inner pipe (1) and the inner wall of the outer pipe (2); the sealing device (4) is a rubber sleeve, wherein a suction nozzle (5) is arranged on the rubber sleeve on one side, and a gap formed between the pipe end (7) and the outer wall of the inner pipe (1) and the inner wall of the outer pipe (2) is subjected to vacuum treatment from the suction nozzle (5) until the vacuum degree is less than or equal to-0.08 MPa;
step 3, after the vacuum degree between the outer pipe (2) and the inner pipe (1) is less than or equal to-0.08 MPa, pressurizing the inner wall of the inner pipe (1) of the pipe end (7) by using an inner supporting device (3) to ensure that the outer wall of the inner pipe (1) is tightly attached to the inner wall of the outer pipe (2), wherein the distance between the inner supporting device (3) and the pipe end (7) is 50-100 mm, the applied pressure P is 1.5 x (2t sigma)/D, and in the formula, t is the thickness of the inner pipe wall and mm; σ is the yield strength of the inner tube, MPa; d is the outer diameter of the inner pipe, mm, the sealing device (4) is removed, and the pipe end (7) is sealed and welded;
step 4, mechanically compounding the inner pipe (1) and the outer pipe (2) processed in the step 3 to obtain a vacuum mechanical composite pipe;
and 5, eliminating the residual stress of the vacuum mechanical composite pipe.
2. The manufacturing method of the vacuum mechanical composite pipe according to claim 1, wherein the compounding manner of the inner pipe (1) and the outer pipe (2) in the step 4 is one of hydraulic compounding, deflagration compounding and spinning compounding.
3. The method as claimed in claim 1, wherein the step 5 employs the first three-order vibration frequency of the vacuum mechanical composite tube to eliminate the residual stress of the vacuum mechanical composite tube.
4. The method according to claim 3, wherein the vibration time of the vacuum mechanical composite tube is 5-10 min.
CN201911156966.3A 2019-11-22 2019-11-22 Manufacturing method of vacuum mechanical composite pipe Active CN110906069B (en)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05123875A (en) * 1991-10-29 1993-05-21 Showa Electric Wire & Cable Co Ltd Production of composite pipe
CN1358946A (en) * 2002-01-18 2002-07-17 黄勇霖 Double-metal composite pipe and making method thereof
CN202667952U (en) * 2012-06-05 2013-01-16 西安向阳航天材料股份有限公司 Tension device of sealing weld lining at pipe end of mechanical bimetallic composite pipe
CN103574220A (en) * 2013-08-31 2014-02-12 宝鸡石油钢管有限责任公司 Hydraulic pressure expansion liner corrosion resistant alloy composite tube and manufacturing method thereof
CN104235517A (en) * 2014-09-03 2014-12-24 钢铁研究总院 Corrosion-resisting titanium-steel compound pipe and preparation method thereof

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH05123875A (en) * 1991-10-29 1993-05-21 Showa Electric Wire & Cable Co Ltd Production of composite pipe
CN1358946A (en) * 2002-01-18 2002-07-17 黄勇霖 Double-metal composite pipe and making method thereof
CN202667952U (en) * 2012-06-05 2013-01-16 西安向阳航天材料股份有限公司 Tension device of sealing weld lining at pipe end of mechanical bimetallic composite pipe
CN103574220A (en) * 2013-08-31 2014-02-12 宝鸡石油钢管有限责任公司 Hydraulic pressure expansion liner corrosion resistant alloy composite tube and manufacturing method thereof
CN104235517A (en) * 2014-09-03 2014-12-24 钢铁研究总院 Corrosion-resisting titanium-steel compound pipe and preparation method thereof

Non-Patent Citations (2)

* Cited by examiner, † Cited by third party
Title
关于钢岔管振动时效的探讨;雷清华;《水利电力机械》;20071125;第29卷(第11期);全文 *
双金属复合管塑性成型力学分析及其装置的研究;陈海云;《中国优秀博硕士学位论文全文数据库 (硕士)-工程科技Ⅰ辑》;20061215;参见第20、23、27页，图2.1 *

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