CN114310180B - Manufacturing and assembling method of novel 35MPa axial extrusion pipeline connecting piece for aviation - Google Patents
Manufacturing and assembling method of novel 35MPa axial extrusion pipeline connecting piece for aviation Download PDFInfo
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- CN114310180B CN114310180B CN202111653665.9A CN202111653665A CN114310180B CN 114310180 B CN114310180 B CN 114310180B CN 202111653665 A CN202111653665 A CN 202111653665A CN 114310180 B CN114310180 B CN 114310180B
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- pipe joint
- extrusion ring
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- 238000001125 extrusion Methods 0.000 title claims abstract description 106
- 238000000034 method Methods 0.000 title claims abstract description 31
- 238000004519 manufacturing process Methods 0.000 title claims abstract description 27
- 229910001069 Ti alloy Inorganic materials 0.000 claims abstract description 15
- 238000010438 heat treatment Methods 0.000 claims abstract description 14
- 239000000463 material Substances 0.000 claims abstract description 13
- 239000000314 lubricant Substances 0.000 claims abstract description 12
- 238000007789 sealing Methods 0.000 claims abstract description 11
- 239000000956 alloy Substances 0.000 claims abstract description 7
- 238000012545 processing Methods 0.000 claims abstract description 5
- 238000002788 crimping Methods 0.000 claims abstract description 4
- 238000003754 machining Methods 0.000 claims abstract description 4
- CWQXQMHSOZUFJS-UHFFFAOYSA-N molybdenum disulfide Chemical group S=[Mo]=S CWQXQMHSOZUFJS-UHFFFAOYSA-N 0.000 claims description 6
- 229910052982 molybdenum disulfide Inorganic materials 0.000 claims description 6
- 229910000883 Ti6Al4V Inorganic materials 0.000 claims description 5
- 230000032683 aging Effects 0.000 claims description 4
- 238000000576 coating method Methods 0.000 claims description 4
- -1 polytetrafluoroethylene Polymers 0.000 claims description 4
- 229920001343 polytetrafluoroethylene Polymers 0.000 claims description 4
- 239000004810 polytetrafluoroethylene Substances 0.000 claims description 4
- 239000006104 solid solution Substances 0.000 claims description 4
- 238000007664 blowing Methods 0.000 claims description 3
- 238000007906 compression Methods 0.000 claims description 3
- 238000001035 drying Methods 0.000 claims description 3
- 239000004576 sand Substances 0.000 claims description 3
- 238000005507 spraying Methods 0.000 claims description 3
- 206010016256 fatigue Diseases 0.000 description 4
- 238000005452 bending Methods 0.000 description 3
- 238000005516 engineering process Methods 0.000 description 3
- 239000013585 weight reducing agent Substances 0.000 description 3
- 230000009286 beneficial effect Effects 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 239000000446 fuel Substances 0.000 description 2
- 238000009434 installation Methods 0.000 description 2
- 238000005461 lubrication Methods 0.000 description 2
- 208000013201 Stress fracture Diseases 0.000 description 1
- 239000011248 coating agent Substances 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 239000010720 hydraulic oil Substances 0.000 description 1
- 238000012423 maintenance Methods 0.000 description 1
- 239000003921 oil Substances 0.000 description 1
- 238000012827 research and development Methods 0.000 description 1
- 239000000243 solution Substances 0.000 description 1
- 238000003860 storage Methods 0.000 description 1
Landscapes
- Non-Disconnectible Joints And Screw-Threaded Joints (AREA)
Abstract
The invention discloses a manufacturing and assembling method of a novel 35MPa axial extrusion pipeline connecting piece for aviation, wherein an extrusion ring and a pipe joint are manufactured through machining; titanium alloy is selected as materials for manufacturing the extrusion ring and the pipe joint, the titanium alloy materials are processed through a heat treatment process, and then the extrusion ring and the pipe joint with standard shapes are manufactured through mechanical processing, so that the manufactured extrusion ring and pipe joint achieve required tensile strength; the inner surfaces of the inner surface, the outer surface and the two ports of the pipe joint of the extrusion ring are coated with dry film lubricant, and the outer surface of the extrusion ring is provided with a marking part; when the axial extrusion pipeline connecting piece is assembled on the airplane, the extrusion ring and the pipe joint of the axial extrusion pipeline connecting piece are arranged at the preset position of the guide pipe, the extrusion ring is extruded onto the pipe joint through the axial extrusion force of the special crimping tool, and the radial extrusion deformation connection of the pipe joint and the guide pipe is completed through the radial size difference of the extrusion ring and the pipe joint, so that the sealing of the pipe joint and the guide pipe is realized.
Description
Technical Field
The invention belongs to the technical field of pipeline connectors for aviation and aerospace, and particularly relates to a manufacturing and assembling method of a novel 35MPa axial extrusion pipeline connector for aviation.
Background
In order to improve the flying performance of an international advanced aircraft, a hydraulic system is improved to 35MPa, meanwhile, the requirement of corresponding system pressure and performance index requirements is also required to be met by the conduit connection of the hydraulic system, and the 35MPa axial extrusion pipeline connector is an international advanced conduit connector and has the characteristics of high bearing pressure, simple structure, light weight, fatigue resistance, vibration resistance, good sealing performance, safety, reliability, simplicity in installation and operation and the like, and is widely applied to the hydraulic systems of civil and military aircraft such as F-16, F-35B, C-17, V-22, A320, A380 and the like. The pressure of the hydraulic system of the airplane is increased to 35MPa, the weight of the hydraulic system of the airplane is greatly reduced, and the maneuvering performance and tactical performance of the airplane are improved.
At present, the domestic aviation hydraulic system adopts 74-degree flaring pipeline connecting pieces, and the pipe joint of the pipeline connecting pieces has the defects of low system pressure, poor sealing performance and inconvenient installation, and also has the risk of fatigue fracture. While the 35MPa axial extrusion pipeline connector in China is in the research and development stage, no method for designing, processing and manufacturing and assembling the 35MPa axial extrusion pipeline connector product is known.
Disclosure of Invention
The invention aims at the problems, overcomes the defects of the prior art, and provides a novel 35MPa axial extrusion pipeline connecting piece manufacturing and assembling method for aviation, which is perfect in technology. The novel 35MPa axial extrusion pipeline connecting piece manufactured by the manufacturing and assembling method solves the problems of the prior domestic aviation hydraulic system adopting a 74-degree flaring pipeline connecting piece; the 35MPa axial extrusion pipeline connecting piece meets the aviation technical requirements, and meets the performance indexes of sealing, connecting strength, weight reduction, bending fatigue life and the like.
In order to achieve the above purpose, the present invention adopts the following technical scheme.
The invention relates to a manufacturing and assembling method of an aviation 35MPa axial extrusion pipeline connecting piece, which comprises an extrusion ring and a pipe joint, wherein the extrusion ring and the pipe joint are manufactured by machining;
titanium alloy is selected as materials for manufacturing the extrusion ring and the pipe joint, firstly, the titanium alloy materials are processed through a heat treatment process, and then the extrusion ring and the pipe joint with standard shapes are manufactured through mechanical processing, so that the manufactured extrusion ring and pipe joint achieve the required tensile strength;
the inner surfaces of the inner surface, the outer surface and the two ports of the pipe joint of the extrusion ring are coated with dry film lubricant, and the outer surface of the extrusion ring is provided with a marking part;
when the axial extrusion pipeline connecting piece is assembled on the airplane, the extrusion ring and the pipe joint of the axial extrusion pipeline connecting piece are arranged at the preset position of the guide pipe, the extrusion ring is extruded onto the pipe joint through the axial extrusion force of the special crimping tool, and the radial extrusion deformation connection of the pipe joint and the guide pipe is completed through the radial size difference of the extrusion ring and the pipe joint, so that the sealing of the pipe joint and the guide pipe is realized.
As a preferable scheme of the invention, the materials for manufacturing the extrusion ring and the pipe joint are titanium alloy with the model of Ti-6Al-4V, and the titanium alloy material for manufacturing the extrusion ring is treated by a solid solution and aging heat treatment process.
As another preferable mode of the present invention, the extrusion ring is made to have a required tensile strength of 1100MPa by a heat treatment process, and the pipe joint is made to have a required tensile strength of 900MPa by a heat treatment process.
As another preferable scheme of the invention, the dry film lubricant coated on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint is molybdenum disulfide.
As another preferable scheme of the invention, the coating process of the dry film lubricant molybdenum disulfide on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint comprises sand blowing, spraying and drying.
As another preferable mode of the invention, the marking part on the outer surface of the extrusion ring is coated blue polytetrafluoroethylene.
The invention has the beneficial effects that:
1. the novel 35MPa axial extrusion pipeline connecting piece manufactured by the manufacturing and assembling method solves the problems of the prior domestic aviation hydraulic system adopting a 74-degree flaring pipeline connecting piece; the 35MPa axial extrusion pipeline connecting piece meets the aviation technical requirements, and meets the performance indexes of sealing, connecting strength, weight reduction, bending fatigue life and the like.
2. The manufacturing and assembling method can finish the material selection, dry film lubrication, identification and final assembly of the pipe joint of the axial extrusion pipeline connecting piece and the extrusion ring.
Detailed Description
In order to make the technical problems, technical schemes and beneficial effects solved by the invention more clear, the invention is further described in detail below with reference to the specific embodiments. It should be understood that the detailed description is presented by way of example only and is not intended to limit the invention.
The invention relates to a manufacturing and assembling method of an aviation 35MPa axial extrusion pipeline connecting piece, which comprises an extrusion ring and a pipe joint, wherein the extrusion ring and the pipe joint are manufactured by machining; titanium alloy is selected as materials for manufacturing the extrusion ring and the pipe joint, firstly, the titanium alloy materials are processed through a heat treatment process, and then the extrusion ring and the pipe joint with standard shapes are manufactured through mechanical processing, so that the manufactured extrusion ring and pipe joint achieve the required tensile strength; the inner surfaces of the inner surface, the outer surface and the two ports of the pipe joint of the extrusion ring are coated with dry film lubricant, and the outer surface of the extrusion ring is provided with a marking part; when the axial extrusion pipeline connecting piece is assembled on the airplane, the extrusion ring and the pipe joint of the axial extrusion pipeline connecting piece are arranged at the preset position of the guide pipe, the extrusion ring is extruded onto the pipe joint through the axial extrusion force of the special crimping tool, and the radial extrusion deformation connection of the pipe joint and the guide pipe is completed through the radial size difference of the extrusion ring and the pipe joint, so that the sealing of the pipe joint and the guide pipe is realized.
The materials for manufacturing the extrusion ring and the pipe joint are titanium alloy with the model of Ti-6Al-4V, and the titanium alloy material for manufacturing the extrusion ring is treated by a solid solution and aging heat treatment process.
The material selection of the extrusion ring and the pipe joint is a key step for ensuring that the axial extrusion pipeline connecting piece meets the aviation technical requirements, and is a necessary condition for meeting performance indexes such as sealing, connecting strength, weight reduction, bending fatigue life and the like, and the material selection of the extrusion ring and the pipe joint and the tensile mechanical performance indexes of the manufactured extrusion ring and pipe joint are shown in the following table 1.
TABLE 1
| Part name | Material brand | Material state | Heat treatment of | Tensile strength of |
| Pipe joint | Ti-6Al-4V | M | —— | 900MPa |
| Extrusion ring | Ti-6Al-4V | M | Solid solution + aging | 1100MPa |
The extrusion ring manufactured by the heat treatment process reaches the required tensile strength of 1100MPa, and the pipe joint manufactured by the heat treatment process reaches the required tensile strength of 900 MPa.
The dry film lubricant coated on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint is molybdenum disulfide.
The coating process of the dry film lubricant molybdenum disulfide on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint comprises sand blowing, spraying and drying.
The dry film lubricant is coated on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint, so that the extrusion ring is prevented from generating surface scratches when axially moving on the pipe joint in the assembly process of the axial extrusion pipeline connecting piece; the choice of lubricant coating on the inside surface of the extrusion ring, the outside surface of the pipe joint, and the inside surface at the two ports of the pipe joint is shown in table 2 below.
TABLE 2
The marking part on the outer surface of the extrusion ring is coated blue polytetrafluoroethylene, specifically, in order to ensure the uniqueness and convenient identification of the axial extrusion pipeline connecting piece product, the surface of the extrusion ring is coated with marking color, and the outer surface of the extrusion ring is coated with blue polytetrafluoroethylene according to the particularity of the axial extrusion pipeline connecting piece.
The invention aims to provide a manufacturing and assembling method for completing material selection, dry film lubrication, identification and final assembly of a pipe joint and a squeezing ring.
The axial extrusion pipeline connecting piece with the specification of 35MPa can be designed and manufactured by using the manufacturing and assembling method, and the connecting strength and the sealing performance of the axial extrusion pipeline connecting piece can meet the requirements; specifically, the 35MPa axial-compression piping connection manufactured by using the manufacturing assembly formula of the present invention has the following advantages:
(1) The hydraulic system is suitable for pipeline connection of an aviation hydraulic system with high pressure of 35MPa, improves the pressure of the hydraulic system, and reduces the volumes of a system executing mechanism and an oil storage tank.
(2) The sealing performance is good, the leakage of hydraulic oil can not be generated, and the safety and reliability are realized.
(3) The connecting strength is high, and the method is suitable for various stressed occasions.
(4) The device is convenient to install, simple to operate, suitable for various occasions or field operations and capable of meeting the requirement of rapid maintenance in the war.
(5) The conduit matched with the axial extrusion pipeline connecting piece does not need flaring, and a titanium alloy conduit can be adopted, so that the weight of a hydraulic system pipeline is reduced, the flight fuel consumption of an airplane is reduced, and the tactical performance of the airplane is improved.
(6) The implementation of the invention can ensure the technical key of the axial extrusion pipeline connecting piece, improve the application level of the pipeline connecting piece of the aviation hydraulic system in China, improve the technical level of the hydraulic system of the domestic fighter plane and the civil aircraft, lead the pipeline connecting technology of the hydraulic system of the domestic aircraft to catch up with the international advanced level, and improve the safety and the reliability of the hydraulic system of the domestic aircraft. In the aspect of economy, the invention can realize that the pipeline connection technology of the aviation hydraulic system is improved to 35MPa, so that the pressure of the hydraulic system of the airplane is improved, the weight of the hydraulic system of the airplane is lightened, the flight performance of the airplane is improved, the fuel consumption of the airplane is reduced, and the social benefit is obviously improved.
It should be understood that the foregoing detailed description of the present invention is provided for illustration only and is not limited to the technical solutions described in the embodiments of the present invention, and those skilled in the art should understand that the present invention may be modified or substituted for the same technical effects; as long as the use requirement is met, the invention is within the protection scope of the invention.
Claims (3)
1. A manufacturing and assembling method of an aviation 35MPa axial extrusion pipeline connector is characterized by comprising the following steps of: the extrusion ring and the pipe joint are manufactured by machining;
titanium alloy is selected as materials for manufacturing the extrusion ring and the pipe joint, firstly, the titanium alloy materials are processed through a heat treatment process, and then the extrusion ring and the pipe joint with standard shapes are manufactured through mechanical processing, so that the manufactured extrusion ring and pipe joint achieve the required tensile strength;
the inner surfaces of the inner surface, the outer surface and the two ports of the pipe joint of the extrusion ring are coated with dry film lubricant, and the outer surface of the extrusion ring is provided with a marking part;
when the axial extrusion pipeline connecting piece is assembled on the airplane, the extrusion ring and the pipe joint of the axial extrusion pipeline connecting piece are arranged at the preset position of the guide pipe, the extrusion ring is extruded onto the pipe joint through the axial extrusion force of the special crimping tool, and the radial extrusion deformation connection of the pipe joint and the guide pipe is completed through the radial size difference of the extrusion ring and the pipe joint, so that the sealing of the pipe joint and the guide pipe is realized;
the dry film lubricant coated on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint is molybdenum disulfide; the coating process of the dry film lubricant molybdenum disulfide on the inner surface of the extrusion ring, the outer surface of the pipe joint and the inner surfaces of two ports of the pipe joint comprises sand blowing, spraying and drying; the marking part on the outer surface of the extrusion ring is coated blue polytetrafluoroethylene.
2. The method for manufacturing and assembling an aviation 35MPa axial-compression pipeline connector according to claim 1, wherein: the materials for manufacturing the extrusion ring and the pipe joint are titanium alloy with the model of Ti-6Al-4V, and the titanium alloy material for manufacturing the extrusion ring is treated by a solid solution and aging heat treatment process.
3. The method for manufacturing and assembling an aviation 35MPa axial-compression pipeline connector according to claim 1, wherein: the extrusion ring manufactured by the heat treatment process reaches the required tensile strength of 1100MPa, and the pipe joint manufactured by the heat treatment process reaches the required tensile strength of 900 MPa.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111653665.9A CN114310180B (en) | 2021-12-30 | 2021-12-30 | Manufacturing and assembling method of novel 35MPa axial extrusion pipeline connecting piece for aviation |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202111653665.9A CN114310180B (en) | 2021-12-30 | 2021-12-30 | Manufacturing and assembling method of novel 35MPa axial extrusion pipeline connecting piece for aviation |
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| Publication Number | Publication Date |
|---|---|
| CN114310180A CN114310180A (en) | 2022-04-12 |
| CN114310180B true CN114310180B (en) | 2024-01-05 |
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Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1975548U (en) * | 1967-09-23 | 1967-12-21 | Karl Walter Bell | CRIMP RING AS SEAL FOR PIPE CONNECTIONS. |
| DE1957565A1 (en) * | 1969-11-15 | 1971-05-19 | Tracto Technik | Device for connecting a cutting ring pipe union to a hydraulic pipe |
| FR2450671A1 (en) * | 1979-03-09 | 1980-10-03 | Seperef | Hand press for making sealed joint in pipes - has two chained rocking jaws connected by pinned tie to hand levers |
| US4696085A (en) * | 1982-02-04 | 1987-09-29 | Firma Compat Aktiengesellschaft | Apparatus for pressing tubular parts |
| KR20070097176A (en) * | 2006-03-28 | 2007-10-04 | 아시아 바이탈 컴포넌츠 컴퍼니 리미티드 | Method for producing slab heat pipe and method for joining its case |
| ITRA20100030A1 (en) * | 2010-10-22 | 2011-01-21 | Ipm S R L | GASKET INSERTION SYSTEM IN THE GLASS JOINT OF A PLASTIC AND CONTEMPORARY TUBE CHECKING ITS POSITIONING |
| CN103627927A (en) * | 2012-08-24 | 2014-03-12 | 东港市东方高新金属材料有限公司 | Titanium alloy extruded pipe or rolled pipe and preparation method thereof |
| CN104611657A (en) * | 2015-01-08 | 2015-05-13 | 太原理工大学 | Machining method for titanium alloy bushing joint |
| CN112066103A (en) * | 2020-10-10 | 2020-12-11 | 大连长之琳科技发展有限公司 | Axial extrusion type connecting pipe joint assembly and pipe joint formed by same |
-
2021
- 2021-12-30 CN CN202111653665.9A patent/CN114310180B/en active Active
Patent Citations (9)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| DE1975548U (en) * | 1967-09-23 | 1967-12-21 | Karl Walter Bell | CRIMP RING AS SEAL FOR PIPE CONNECTIONS. |
| DE1957565A1 (en) * | 1969-11-15 | 1971-05-19 | Tracto Technik | Device for connecting a cutting ring pipe union to a hydraulic pipe |
| FR2450671A1 (en) * | 1979-03-09 | 1980-10-03 | Seperef | Hand press for making sealed joint in pipes - has two chained rocking jaws connected by pinned tie to hand levers |
| US4696085A (en) * | 1982-02-04 | 1987-09-29 | Firma Compat Aktiengesellschaft | Apparatus for pressing tubular parts |
| KR20070097176A (en) * | 2006-03-28 | 2007-10-04 | 아시아 바이탈 컴포넌츠 컴퍼니 리미티드 | Method for producing slab heat pipe and method for joining its case |
| ITRA20100030A1 (en) * | 2010-10-22 | 2011-01-21 | Ipm S R L | GASKET INSERTION SYSTEM IN THE GLASS JOINT OF A PLASTIC AND CONTEMPORARY TUBE CHECKING ITS POSITIONING |
| CN103627927A (en) * | 2012-08-24 | 2014-03-12 | 东港市东方高新金属材料有限公司 | Titanium alloy extruded pipe or rolled pipe and preparation method thereof |
| CN104611657A (en) * | 2015-01-08 | 2015-05-13 | 太原理工大学 | Machining method for titanium alloy bushing joint |
| CN112066103A (en) * | 2020-10-10 | 2020-12-11 | 大连长之琳科技发展有限公司 | Axial extrusion type connecting pipe joint assembly and pipe joint formed by same |
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| Publication number | Publication date |
|---|---|
| CN114310180A (en) | 2022-04-12 |
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