CN114571075B - Welding method of miniature fission chamber signal outgoing line - Google Patents

Welding method of miniature fission chamber signal outgoing line Download PDF

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Publication number
CN114571075B
CN114571075B CN202210268334.1A CN202210268334A CN114571075B CN 114571075 B CN114571075 B CN 114571075B CN 202210268334 A CN202210268334 A CN 202210268334A CN 114571075 B CN114571075 B CN 114571075B
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welding
signal
welded
insulating
kovar
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CN114571075A (en
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温中伟
言杰
韩子杰
王玫
胡永宏
刘百力
尹振羽
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Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics
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Institute of Nuclear Physics and Chemistry China Academy of Engineering Physics
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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/20—Bonding
    • B23K26/21—Bonding by welding
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/60—Preliminary treatment
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B23K26/70—Auxiliary operations or equipment
    • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
    • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
    • Y02E—REDUCTION OF GREENHOUSE GAS [GHG] EMISSIONS, RELATED TO ENERGY GENERATION, TRANSMISSION OR DISTRIBUTION
    • Y02E30/00—Energy generation of nuclear origin
    • Y02E30/30—Nuclear fission reactors

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  • Engineering & Computer Science (AREA)
  • Physics & Mathematics (AREA)
  • Optics & Photonics (AREA)
  • Plasma & Fusion (AREA)
  • Mechanical Engineering (AREA)
  • Laser Beam Processing (AREA)
  • Butt Welding And Welding Of Specific Article (AREA)

Abstract

Aiming at the problems that the welding space is small and the welding is difficult when the ultra-fine core and the wire in the miniature fission chamber are welded, the fusing, the virtual joint and the overlarge welding spot stress are easy to occur in the welding process, the invention provides a welding method of the signal outgoing wire of the miniature fission chamber. The method comprises the following steps: alcohol cleaning of the parts to be welded; one end of the signal outgoing line is sintered into a sphere and then is butt-welded with the end face of the kovar signal column; detecting the strength of welding spots by using a tension meter; winding the signal outgoing line into a spiral shape after the welding strength is qualified; the other end of the signal outgoing line and the end to be welded of the driving cable core wire are sintered into balls and then butt-welded; and (5) detecting the strength of the welding spots by using a tension meter, and finishing the welding assembly of the superfine core and the wire if the strength is qualified. The method not only improves the lap joint condition of the whole superfine core wire, reduces the welding difficulty, ensures the strength of welding spots, but also ensures that the welding spots work at a lower stress level in the subsequent use process, realizes the high-reliability assembly of the miniature fission chamber, and ensures the accuracy of the fluence rate measurement.

Description

Welding method of miniature fission chamber signal outgoing line
Technical Field
The invention belongs to the field of welding of micro devices, and particularly relates to a welding method of a micro fission chamber ultrafine signal outgoing line.
Background
In 2019, the institute of China's engineering and physics institute of science and chemistry was jointly developed to realize the measurement of neutron fluence rate in a reactor core finger sleeve for a miniature fission chamber neutron detector for a CPR1000 reactor. Because the reactor core finger sleeve space is narrow, in order to improve the space utilization rate and the tightness of the miniature fission chamber, each part in the reactor core finger sleeve is very small in design, and each part is connected and sealed and assembled in a welding mode, so that the production and assembly process requirements of the miniature fission chamber parts are high.
The miniature fission chamber is characterized in that the insulating kovar signal column and the driving cable are welded and assembled through a signal outgoing line. Firstly, the diameter of an insulating Kovar signal column is 1.0mm, the diameter of a driving cable core wire is 0.20mm, and the diameter of a signal outgoing line is only 0.15mm, and the insulating Kovar signal column belongs to ultra-fine material welding. The superfine material is easy to generate defects of fusing, virtual connection of welding spots, overlarge stress of welding spots, easy disconnection and the like, which influence the strength of the welding spots, and the micro fission chamber is broken in the working engineering, so that the measurement of neutron fluence rate in the reactor core finger sleeve is influenced. Secondly, the assembly space between the insulating kovar signal column and the driving cable core wire is limited, the assembly space is only the inner space of the insulating ring, the diameter of the assembly space is about 2.7mm, the welding space is limited, and the welding spot strength detection space is limited.
In order to ensure reliable connection between the insulating kovar signal column and the driving cable core wire in the micro fission chamber, improve the normal working time of the micro fission chamber and ensure the neutron fluence rate measurement of the reactor core finger sleeve, a set of welding assembly process or method is required to be designed aiming at superfine materials such as the insulating kovar signal column, the signal outgoing line, the driving cable core wire and the like in the micro fission chamber.
Disclosure of Invention
In order to achieve the purpose, a welding method of a micro fission chamber ultrafine signal outgoing line is provided:
a welding method of a micro fission chamber ultrafine signal outgoing line comprises the following steps:
s1, cleaning, dehydrating and drying the whole section of the signal outgoing line, the end to be welded of the insulating kovar signal column and the end to be welded of the driving cable core wire by using alcohol;
s2, one end of the signal outgoing line is sintered and fused into a spherical end to be welded by using laser welding, the spherical end to be welded is in butt joint with the end face of the insulating kovar signal column, and the welding of the insulating kovar signal column and the signal outgoing line is completed by using laser spot welding;
s3, testing the strength of a welding spot between the insulating kovar signal column and the signal outgoing line by using a tension meter, and if the strength of the welding spot is more than or equal to 3 pounds, welding the insulating kovar signal column and the signal outgoing line to be qualified;
s4, winding the signal outgoing line into a spiral shape, wherein the outer diameter of the spiral shape is smaller than the inner diameter of the insulating ring;
s5, the other end of the signal outgoing line is welded into a spherical to-be-welded end by using laser welding, the to-be-welded end of the driving cable core wire is also welded into a spherical to-be-welded end by using laser welding, the two spherical to-be-welded ends are butted, and the welding of the driving cable core wire and the signal outgoing line is completed by using laser spot welding;
s6, testing the strength of a welding spot between the driving cable core wire and the signal outgoing wire by using a tension meter, and if the strength of the welding spot is more than or equal to 3 pounds, welding the driving cable core wire and the signal outgoing wire to be qualified, thereby finishing welding assembly between the insulating Kovar signal column and the driving cable core wire.
Preferably, in step S1, the end surface to be welded of the insulating kovar signal column is perpendicular to the axis of the insulating kovar signal column.
Preferably, in the step S2, when the spherical end to be welded of the signal outgoing line is in butt joint with the end face of the insulating kovar signal column, the spherical end to be welded of the signal outgoing line must not exceed the edge of the end face of the insulating kovar signal column.
Preferably, in the step S2, when the spherical end to be welded of the signal outgoing line is in butt joint with the end face of the insulating kovar signal column, the signal outgoing line ball is coaxial with the insulating kovar signal column, so that the spherical end to be welded of the signal outgoing line is ensured to be positioned at the center of the end face of the insulating kovar signal column.
Preferably, the number of turns of the signal outgoing line wound into a spiral in step S4 is two.
Preferably, the spherical diameter of the spherical to-be-welded end of the signal outgoing line in the step S2 and the step S5 is 0.2-0.3 mm, and the spherical diameter of the spherical to-be-welded end of the driving cable core wire in the step S5 is 0.3mm.
Preferably, in the step S2, the welding power used for the laser spot welding of the insulating kovar signal column and the signal outgoing line is 40W, and in the step S5, the welding power used for the laser spot welding of the signal outgoing line and the driving cable core wire is 30W.
The beneficial effects of the invention are as follows: (1) By increasing spherical ends to be welded, the overlap area of the ends to be welded of the superfine materials is increased, the centering degree of the two ends to be welded or the coaxiality of the two superfine materials are improved, the overlap condition of the superfine materials is improved, the welding strength of welding spots of the superfine materials is greatly improved, and the welding spot strength is ensured to meet the requirements. (2) The superfine signal outgoing line is spirally wound, so that the welding space is improved, and the welding difficulty of the superfine signal outgoing line and the driving cable core wire is reduced. (3) Compared with the process without spiral winding, the stress of welding spots is relatively smaller, so that the stress of welding spots at two ends of the signal outgoing wire after insulation kovar assembly is reduced to be kept at a relatively lower level. Finally, the high-reliability assembly of tiny and superfine parts of the miniature fission chamber is realized, and the accuracy of the measurement of the fluence rate is ensured.
Drawings
In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the drawings required for the description of the embodiments will be briefly described below, it being obvious that the drawings in the following description are only some embodiments of the present invention, and that other drawings may be obtained according to these drawings without creating effort for a person skilled in the art. The present invention will be described in detail with reference to the accompanying drawings.
FIG. 1 is a schematic diagram of a spiral signal outlet;
FIG. 2 is an insulating kovar schematic;
FIG. 3 is a schematic diagram of a drive cable core;
in the figure: 1. the signal outgoing line, 2, insulating kovar, 3, the driving cable core wire, 11, the first end to be welded of the signal outgoing line, 12, the second end to be welded of the signal outgoing line, 13, the spiral part, 21, insulating kovar signal column, 22, the end to be welded of the signal column, 31 and the end to be welded of the driving cable core wire.
Detailed Description
The present invention will be described in further detail with reference to the following detailed description and the accompanying drawings, in order to make the objects, technical solutions and advantages of the present invention more apparent.
Example 1
Fig. 1-3 show schematic structural diagrams of a signal outlet 1, an insulated kovar 2 and a drive cable core 3, respectively, in a mini-fission chamber of a CPR1000 reactor. The diameter of the insulating Kovar signal column 21 is 1.0mm, the diameter of the driving cable core wire 3 is 0.20mm, the diameter of the signal outgoing wire 1 is only 0.15mm, and the insulating Kovar signal column belongs to ultra-fine material welding.
In order to ensure reliable connection between the insulating kovar signal column and the driving cable core wire in the mini fission chamber and improve welding conditions, the welding is carried out according to the following steps:
(1) Alcohol is used for cleaning, dehydrating and drying the whole section of the signal outgoing line 1, the insulating kovar signal column to be welded 22 and the driving cable core wire to be welded end 31, so as to remove oil stains on the surface;
(2) In order to improve the lap joint condition of the superfine signal outgoing line 1 and the insulating kovar signal column 21, the first end to be welded 11 of the signal outgoing line is sintered and fused into a spherical end to be welded with the spherical diameter of 0.2-0.3 mm by using laser welding, the spherical end to be welded is in butt joint with the end face of the end to be welded 22 of the insulating kovar signal column 21, and the spherical end to be welded of the first end to be welded 11 of the signal outgoing line cannot exceed the end face of the end to be welded 22 of the signal column. Preferably, the signal outgoing line 1 and the insulating kovar signal column 21 are coaxial as much as possible, the spherical to-be-welded end of the first to-be-welded end 11 of the signal outgoing line is ensured to be positioned at the center of the end face of the to-be-welded end 22 of the insulating kovar signal column, then welding power is regulated to 40W, spot welding is carried out, and welding of the insulating kovar signal column 21 and the signal outgoing line 1 is completed;
(3) Testing the strength of a welding spot between the insulating kovar signal column 21 and the signal outgoing line 1 by using a tension meter, if the strength of the welding spot is more than or equal to 3 pounds, welding between the insulating kovar signal column 21 and the signal outgoing line 1 is qualified, and then carrying out the next step; otherwise, the welding is not qualified, and the steps (1) to (3) are continuously repeated for re-welding by using a new insulating kovar signal column and a new signal outgoing line;
(4) The signal outgoing line 1 is wound into a spiral shape to form a spiral part 13, so that the welding difficulty of the second to-be-welded end 12 of the signal outgoing line and the driving cable core wire 3 is reduced, the welding space is increased, and the outer diameter of the spiral part 13 is smaller than the inner diameter of the insulating ring; the insulating ring is positioned between the insulating kovar and the driving cable, and the inner diameter of the insulating ring is not more than 2.7mm; meanwhile, the number of turns of the spiral part 13 is two, and after the two ends of the signal wire 1 are welded, extrusion can occur during assembly of the insulating kovar 2 to increase welding spot stress, so that the service life is influenced; the number of turns is small, and the welding difficulty is increased.
(5) The second end 12 to be welded of the signal outgoing line is also welded into a spherical end to be welded with the spherical diameter of 0.2-0.3 mm by using laser welding, the end 31 to be welded of the driving cable core wire is also welded into a spherical end to be welded with the spherical diameter of 0.3mm, the lap joint probability is increased, the lap joint condition is improved, then the two spherical ends to be welded are butted, the welding power is adjusted to 30W, and the welding of the driving cable core wire 3 and the signal outgoing line 1 is completed by laser spot welding;
(6) And (3) testing the strength of a welding spot between the driving cable core wire 3 and the signal outgoing wire 1 by using a tension meter, and if the strength of the welding spot is more than or equal to 3 pounds, welding the driving cable core wire 3 and the signal outgoing wire 1 to be qualified, thereby finishing the welding assembly between the insulating Kovar signal column 21 and the driving cable core wire 3.
In order to ensure the overlapping effect, the end face of the signal post to be welded 22 of the insulating kovar is preferably perpendicular to the axis of the signal post.
According to the measurement, the ultra-fine material welding assembly is carried out according to the method, so that the lap joint condition of the whole welding process is improved, the welding difficulty of the ultra-fine material is reduced, the strength of welding spots is ensured, meanwhile, the welding spots are ensured to work at a lower stress level in the use process after the assembly, the high-reliability assembly of micro and ultra-fine parts of the miniature fission chamber is finally realized, and the accuracy of the measurement of the fluence rate is ensured.

Claims (7)

1. A welding method of a micro fission chamber ultrafine signal outgoing line comprises the following steps:
s1, cleaning, dehydrating and drying the whole section of the signal outgoing line, the end to be welded of the insulating kovar signal column and the end to be welded of the driving cable core wire by using alcohol;
s2, one end of the signal outgoing line is sintered and fused into a spherical end to be welded by using laser welding, the spherical end to be welded is in butt joint with the end face of the insulating kovar signal column, and the welding of the insulating kovar signal column and the signal outgoing line is completed by using laser spot welding;
s3, testing the strength of a welding spot between the insulating kovar signal column and the signal outgoing line by using a tension meter, and if the strength of the welding spot is more than or equal to 3 pounds, welding the insulating kovar signal column and the signal outgoing line to be qualified;
s4, winding the signal outgoing line into a spiral shape, wherein the outer diameter of the spiral shape is smaller than the inner diameter of the insulating ring;
s5, the other end of the signal outgoing line is welded into a spherical to-be-welded end by using laser welding, the to-be-welded end of the driving cable core wire is also welded into a spherical to-be-welded end by using laser welding, the two spherical to-be-welded ends are butted, and the welding of the driving cable core wire and the signal outgoing line is completed by using laser spot welding;
s6, testing the strength of a welding spot between the driving cable core wire and the signal outgoing wire by using a tension meter, and if the strength of the welding spot is more than or equal to 3 pounds, welding the driving cable core wire and the signal outgoing wire to be qualified, thereby finishing welding assembly between the insulating Kovar signal column and the driving cable core wire.
2. The welding method according to claim 1, wherein the end face to be welded of the insulating kovar signal column in step S1 is perpendicular to the axis of the insulating kovar signal column.
3. The welding method according to claim 1, wherein in step S2, when the spherical end to be welded of the signal lead wire is butted with the end face of the insulating kovar signal post, the spherical end to be welded of the signal lead wire must not exceed the edge of the end face of the insulating kovar signal post.
4. The welding method according to claim 1, wherein in step S2, when the spherical end to be welded of the signal outgoing line is butted with the end face of the insulating kovar signal column, the signal outgoing line ball is coaxial with the insulating kovar signal column, so that the spherical end to be welded of the signal outgoing line is ensured to be positioned at the center of the end face of the insulating kovar signal column.
5. The welding method according to claim 1, wherein the number of turns of the signal lead-out wire wound in a spiral shape in step S4 is two.
6. The welding method according to claim 1, wherein the spherical diameter of the spherical end to be welded of the signal outgoing line in the steps S2 and S5 is 0.2mm to 0.3mm, and the spherical diameter of the spherical end to be welded of the driving cable core wire in the step S5 is 0.3mm.
7. The welding method according to claim 1, wherein the welding power used for the laser spot welding of the insulating kovar signal post and the signal lead wire in step S2 is 40W, and the welding power used for the laser spot welding of the signal lead wire and the driving cable core wire in step S5 is 30W.
CN202210268334.1A 2022-03-17 2022-03-17 Welding method of miniature fission chamber signal outgoing line Active CN114571075B (en)

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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN85107767A (en) * 1985-10-15 1987-04-15 长春光学精密机械学院 Laser welding method for bridge wire
CN102341210A (en) * 2009-03-02 2012-02-01 德克·豪斯曼 Method and apparatus for welding wires, including an annealing process prior to, during, or following the welding process, wires, and application of small pipe in the method
CN103549664A (en) * 2013-08-07 2014-02-05 林光榕 Heating wire component in electronic cigarette and welding method of heating wire component
CN104785925A (en) * 2014-01-22 2015-07-22 上海亚尔光源有限公司 Electrode molybdenum sheet assembly for ultrahigh-voltage point light source and forming method thereof
CN105607188A (en) * 2016-03-09 2016-05-25 南京吉隆光纤通信股份有限公司 Double-electrode fiber Fabry-Perot cavity welding device
CN113764953A (en) * 2020-06-04 2021-12-07 泰连德国有限公司 Soldering method for connecting a first connector and a second connector, use and connection

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN85107767A (en) * 1985-10-15 1987-04-15 长春光学精密机械学院 Laser welding method for bridge wire
CN102341210A (en) * 2009-03-02 2012-02-01 德克·豪斯曼 Method and apparatus for welding wires, including an annealing process prior to, during, or following the welding process, wires, and application of small pipe in the method
CN103549664A (en) * 2013-08-07 2014-02-05 林光榕 Heating wire component in electronic cigarette and welding method of heating wire component
CN104785925A (en) * 2014-01-22 2015-07-22 上海亚尔光源有限公司 Electrode molybdenum sheet assembly for ultrahigh-voltage point light source and forming method thereof
CN105607188A (en) * 2016-03-09 2016-05-25 南京吉隆光纤通信股份有限公司 Double-electrode fiber Fabry-Perot cavity welding device
CN113764953A (en) * 2020-06-04 2021-12-07 泰连德国有限公司 Soldering method for connecting a first connector and a second connector, use and connection

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