WO2012122842A1 - 毛细管铜铝焊接接头的制备方法及套接式铜端铝毛细管 - Google Patents

毛细管铜铝焊接接头的制备方法及套接式铜端铝毛细管 Download PDF

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Publication number
WO2012122842A1
WO2012122842A1 PCT/CN2011/084207 CN2011084207W WO2012122842A1 WO 2012122842 A1 WO2012122842 A1 WO 2012122842A1 CN 2011084207 W CN2011084207 W CN 2011084207W WO 2012122842 A1 WO2012122842 A1 WO 2012122842A1
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Prior art keywords
capillary
copper
aluminum
tube
inner core
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PCT/CN2011/084207
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English (en)
French (fr)
Inventor
左铁军
赵越
王昕�
万延尧
杨训
孙德兴
王岩
Original Assignee
Zuo Tiejun
Zhao Yue
Wang Xin
Wan Yanyao
Yang Xun
Sun Dexing
Wang Yan
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Application filed by Zuo Tiejun, Zhao Yue, Wang Xin, Wan Yanyao, Yang Xun, Sun Dexing, Wang Yan filed Critical Zuo Tiejun
Publication of WO2012122842A1 publication Critical patent/WO2012122842A1/zh

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Classifications

    • 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
    • B23K33/00—Specially-profiled edge portions of workpieces for making soldering or welding connections; Filling the seams formed thereby
    • B23K33/004—Filling of continuous seams
    • B23K33/006—Filling of continuous seams for cylindrical workpieces
    • 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
    • B23K2103/00—Materials to be soldered, welded or cut
    • B23K2103/08—Non-ferrous metals or alloys
    • B23K2103/10—Aluminium or alloys thereof
    • 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
    • B23K2103/00—Materials to be soldered, welded or cut
    • B23K2103/08—Non-ferrous metals or alloys
    • B23K2103/12—Copper or alloys thereof
    • 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
    • B23K2103/00—Materials to be soldered, welded or cut
    • B23K2103/18—Dissimilar materials
    • F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
    • F25—REFRIGERATION OR COOLING; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS; MANUFACTURE OR STORAGE OF ICE; LIQUEFACTION SOLIDIFICATION OF GASES
    • F25B—REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
    • F25B41/00—Fluid-circulation arrangements
    • F25B41/30—Expansion means; Dispositions thereof
    • F25B41/37—Capillary tubes

Definitions

  • the present invention relates to a method of preparing a welded joint, and more particularly to a method for preparing a copper-aluminum welded joint of a capillary; the present invention also relates to a sleeved copper-end aluminum capillary obtained by the above method. Background technique
  • the copper capillaries are bundled together to cause electrochemical corrosion. If the copper capillary is also changed to an aluminum capillary, and the aluminum return pipe is bundled with the aluminum capillary, electrochemical corrosion will not occur, so the problem of aluminum-copper of the capillary is proposed.
  • the capillary tube is a relatively thin inner diameter tube.
  • the copper tube with an inner diameter of 0.5 to 0.7 mm is used in the refrigerator industry.
  • the copper tube with a diameter of 0.7 to 2.0 mm is used in the air conditioning industry. Since the inner diameter of the capillary is small, the welding spatter will be The pores are blocked and cannot be removed. Welding methods such as friction welding, energy storage welding, flash butt welding, etc., which are easy to form splashes, cannot be completed.
  • the brazing method using the flare connection requires socketing at the end of the connecting end.
  • the fine diameter of more than 20mm can ensure no welding, and the deep diameter deep expansion is impossible. Therefore, the brazing cannot complete the welding of the thin-diameter copper-aluminum tube. For the same reason, the brazing method cannot complete the copper capillary with the flaring connection.
  • aluminum capillary in summary, the current technology can not achieve capillary copper and aluminum tube welding.
  • the existing sleeve extrusion resistance welding technology uses a copper tube inserted into an aluminum tube for welding, and a flaring after welding. Although a well-densified pipe joint structure can be obtained, the inner diameter of the copper-aluminum pipe fitting suitable for the welding method must be More than 2.0 mm, the inner diameter of the capillary is less than 2.0 mm, and the above method cannot achieve copper-aluminum welding of the capillary. Summary of the invention
  • the technical problem to be solved by the present invention is to overcome the deficiencies of the prior art described above, and to provide a method for preparing a capillary copper-aluminum welded joint, and a sleeve-type copper-end aluminum capillary tube obtained by the method.
  • a method for preparing a capillary copper-aluminum welded joint comprises the following steps:
  • taper p A-0.15xd 1 +3xd 2 -2.7xd 3 , wherein A ranges from 14° to 16°, is the outer diameter of the aluminum tube, d 2 is the outer diameter of the copper tube, and d 3 is aluminum Tube inner diameter.
  • a socket type copper-end aluminum capillary tube comprising an aluminum capillary tube, a capillary end and a welding surface having a taper ⁇ , wherein: the welded joint between the aluminum capillary tube and the copper capillary end is prepared by the above preparation method,
  • a high-temperature rod-shaped inner core which is harder than the copper tube and has a copper tube outside the copper tube is disposed inside the copper tube.
  • the diameter of the inner core is smaller than the inner diameter of the aluminum capillary tube. Since the inner core is harder than the copper tube, in the precision rolling process The inner core can play a very strong supporting role on the copper tube, so that the tube end of the copper tube can be made very thin and sharp.
  • the inner core of the copper tube can be welded to obtain the following benefits: 1) When the copper tube is not welded with the inner core, if the aluminum beads are generated inside the welding, the aluminum beads will block the pipeline and affect the capillary flow; Due to the support of the inner core, the gap between the copper tube and the aluminum tube is small, and no aluminum beads are generated, which does not affect the capillary flow; 2) when the copper tube is not welded with the inner core, due to the welding pressure, The inner diameter of the welded joint is reduced, which affects the capillary flow. When the inner core is welded, the inner diameter of the welded joint is not reduced by the support of the inner core.
  • the inner core After the inner core is withdrawn, the inner diameter remains unchanged, which does not affect the capillary flow; 3) the copper tube Inner core welding, the inner core supports the inner diameter of the welded joint to press the welding area, which is beneficial to reduce the amount of brittle structure in the weld.
  • Taper taper P A-0.15xdl+3xd2-2.7xd3, where A is 14° 16°, dl is the outer diameter of the aluminum tube, d2 is the outer diameter of the copper tube, and d3 is the inner diameter of the aluminum tube.
  • the cone taper ⁇ is limited, on the one hand, the copper tube cone end can be inserted without reaping the aluminum capillary tube, thereby realizing the capillary sleeve extrusion resistance welding machine welding, and the other surface can be significantly Improve the quality of the joints of the welded joints.
  • Figure 1 is a schematic view of the copper capillary cone end inserted into an aluminum capillary for pre-assembly
  • Figure 2 shows the socketed copper-end aluminum capillary after welding.
  • a method for preparing a capillary copper-aluminum welded joint comprises the following steps:
  • taper taper p A-0.15xd 1 +3xd 2 -2.7xd 3 , wherein A ranges from 14° to 16°, ( ⁇ is the outer diameter of the aluminum tube, and d 2 is the outer diameter of the copper tube, d 3 is the inner diameter of the aluminum tube.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Butt Welding And Welding Of Specific Article (AREA)
  • Arc Welding In General (AREA)

Description

.
毛细管铜铝焊雖头的制备方法及套接式铜端铝毛细管 技术领域
本发明涉及一种焊接接头的制备方法， 具体的说涉及一种毛细管铜铝焊接接头的制备方 法； 本发明还涉及使用上述方法制得的套接式铜端铝毛细管。 背景技术
目前铜资源紧缺， 而铝的性能与铜最接近， 并且产量丰富， 所以用铝管取代铜管， 成为 制冷行业节约铜资源、 降低产品制造成本的最有效手段之一。 制冷产品铝代铜的规模也越来 越大， 制冷系统中蒸发器及回气管、 冷凝器、 除露管、 以及系统中的配管陆续实现了铝代铜， 毛细管是制冷产品必备的系统功能件之一， 随着铜价格上升， 铜铝两种毛细管的价格差异高 达 5倍以上， 在一些场合下， 回气管必须与毛细管捆绑在一起使用， 回气管铝代铜后， 铝回 气管继续与铜毛细管捆绑在一起会带来电化学腐蚀， 如果铜毛细管也改为铝毛细管， 铝回气 管与铝毛细管捆绑在一起， 就不会发生电化学腐蚀， 因此提出毛细管的铝代铜课题。
毛细管是一种内径比较细的管路， 目前在冰箱行业使用的是内径 0.5〜0.7mm的铜管； 空 调业使用的是 0.7〜2.0mm的铜管， 由于毛细管内径很小， 焊接飞溅物会堵塞细孔， 且无法清 除， 采用摩擦焊、 储能焊、 闪光对接焊等易形成飞溅的焊接方法是不能完成的； 采用扩口连 接的钎焊方法， 需要在接管一端扩深口进行套接， 细直径超过 20mm才能保证不焊堵， 细直 径深扩口是无法实现的， 所以钎焊不能完成细直径铜铝管焊接， 同样的原因， 钎焊方法也无 法完成采用扩口连接的铜毛细管或铝毛细管， 综上所述目前技术无法实现毛细铜铝管焊接。
已有套管挤压电阻焊接技术采用铜管插入到铝管焊接， 焊接后扩口的方式， 尽管可以获 得致密度好的管路接头结构， 但适合这种焊接方法的铜铝管件的内径必须大于 2.0mm， 毛细 管内径小于 2.0mm,上述方法无法实现毛细管的铜铝焊接。 发明内容
本发明所要解决的技术问题， 就是克服上述已有技术的不足， 提供一种毛细管铜铝焊接 接头的制备方法， 以及使用该方法制得的套接式铜端铝毛细管。
本发明采用如下技术方案：
一种毛细管铜铝焊接接头的制备方法， 包括如下步骤：
( 1 )在铜管内部预置一个比铜管硬， 且两端露出铜管外的耐高温棒状内芯， 该内芯的直 径小于铝毛细管内径； (2)对铜管一端进行加工， 形成具有锥度 β 的焊接面， 此时铜管位于焊接面区域的内径 内收縮， 并且收縮后的内径不小于内芯直径；
( 3 ) 将带有内芯的铜毛细管锥头端插到铝毛细管中进行预装；
(4) 将预装后的铜铝毛细管组件放置到毛细管套管挤压电阻焊机中进行焊接；
( 5 ) 焊接完成后取出内芯。
进一步的， 锥度 p=A-0.15xd1+3xd2-2.7xd3， 其中 A的取值范围为 14° 至 16° ， 为铝管 外径， d2为铜管外径， d3为铝管内径。
一种套接式铜端铝毛细管， 包括铝毛细管、 毛细管端和具有锥度 β 的焊接面， 其特征在 于： 所述的铝毛细管和铜毛细管端之间的焊接接头使用上述的制备方法制备， 所述锥度 β依 据铝管外径 铜管外径 d2、 铝管内径 d3按下述公式确定： β =A— 0. 15>^十3><(12— 2. 7xd3， 其中 A的取值范围为 14°至 16°。
本发明的有益效果是：
在铜管内部预置一个比铜管硬， 且两端露出铜管外的耐高温棒状内芯， 该内芯的直径小 于铝毛细管内径， 由于内芯比铜管硬， 在精密辊锻过程中内芯对铜管可以起到非常有力的支 撑作用， 从而能将铜管锥头端管壁做得非常薄和尖锐。
铜管内带着内芯焊接可以得到以下好处： 1 )铜管不带内芯焊接时， 如果焊接时内部产生 铝珠， 该铝珠会堵塞管路， 影响毛细管流量； 而带着内芯焊接时由于内芯的支撑作用， 铜管 与铝管接触部分内部的缝隙很小， 不会产生铝珠， 不会影响毛细管流量； 2) 铜管不带内芯 焊接时， 由于焊接压力的作用， 焊接接头内径縮小， 影响毛细管流量； 带着内芯焊接时， 焊 接接头内径受到内芯的支撑作用不会縮小， 抽出内芯后， 内径保持不变， 不会影响毛细管流 量； 3 )铜管带内芯焊接， 内芯对焊接接头内径的支撑起到了对焊接区域的挤压作用， 有利于 减少焊缝中脆性组织的数量。
锥头锥度 P=A-0.15xdl+3xd2-2.7xd3， 其中 A取 14° 16° ， dl为铝管外径， d2为铜管 外径， d3 为铝管内径。 之所以对锥头锥度 β进行限制， 一方面可以不需对铝毛细管扩口就可 以将铜管锥头端插进去， 从而实现毛细管套管挤压电阻焊机焊接， 另一发面可以显著提高焊 接接头的连接质量。 附图说明
图 1为铜毛细管锥头端插到铝毛细管中进行预装后的示意图;
图 2为焊接完成后的套接式铜端铝毛细管。
其中： 1一铝毛细管， 2—铜毛细管， 3 内芯。 .
具体实 式
一种毛细管铜铝焊接接头的制备方法， 包括如下步骤：
( 1 )在铜毛细管内部预置一个比铜毛细管硬，且两端露出铜毛细管外的耐高温棒状内芯， 该内芯的直径小于铝毛细管内径；
(2)用精密辊锻机将铜毛细管的一端做锥头处理， 并减薄铜毛细管壁厚， 形成具有一定 锥度锥头 β的焊接面。此时铜毛细管位于焊接面区域的内径内收縮， 并且收縮后的内径不小于 内芯直径， 内芯被卡在锥头处；
( 3 ) 如图 1所示， 将带有内芯的铜毛细管锥头端插到铝毛细管中进行预装；
(4) 将预装后的铜铝毛细管组件放置到毛细管套管挤压电阻焊机中进行焊接；
( 5 ) 焊接完成后取出内芯， 最后就可以得到如图 2所示的套接式铜端铝毛细管。
进一步的， 锥头锥度 p=A-0.15xd1+3xd2-2.7xd3， 其中 A的取值范围为 14° 至 16° ， （^为 铝管外径， d2为铜管外径， d3为铝管内径。

Claims

1. 一种毛细管铜铝焊接接头的制备方法， 其特征在于， 包括如下步骤：
( 1 )在铜管内部预置一个比铜管硬， 且两端露出铜管外的耐高温棒状内芯， 该内芯的直 径小于铝毛细管内径；
(2)对铜管一端进行加工， 形成具有锥度（β ) 的焊接面， 此时铜管位于焊接面区域的 内径内收縮， 并且收縮后的内径不小于内芯直径；
(3) 将带有内芯的铜毛细管锥头端插到铝毛细管中进行预装；
(4) 将预装后的铜铝毛细管组件放置到毛细管套管挤压电阻焊机中进行焊接；
( 5 ) 焊接完成后取出内芯。
2. 根据权利要求 1所述的毛细管铜铝焊接接头的制备方法，其特征在于： 所述锥度（β ) 依据铝管外径 （4)、 铜管外径 （d2)、 铝管内径 （d3) 按下述公式确定： β =Α—0. 15>^十3><(12 -2. 7xd3, 其中 A的取值范围为 14°至 16°。
3. 一种套接式铜端铝毛细管， 包括铝毛细管、 毛细管端和具有锥度 （β ) 的焊接面， 其 特征在于： 所述的铝毛细管和铜毛细管端之间的焊接接头使用权利要求 1所述的制备方法制 备， 所述锥度 （β ) 依据铝管外径 （4)、 铜管外径 （d2)、 铝管内径 （d3) 按下述公式确定： β =Α-0. 15x4 + 3x012— 2. 7xd3， 其中 A的取值范围为 14°至 16°。
PCT/CN2011/084207 2011-03-15 2011-12-19 毛细管铜铝焊接接头的制备方法及套接式铜端铝毛细管 WO2012122842A1 (zh)

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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US20170225259A1 (en) * 2014-12-09 2017-08-10 Origin Electric Company, Limited Bonded article and method for manufacturing bonded article
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Families Citing this family (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN103846537B (zh) * 2014-03-26 2016-06-22 左铁军 异种金属管的焊接方法
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CN109813014A (zh) * 2019-01-25 2019-05-28 江苏通盛换热器有限公司 一种毛细管与铜管连接的结构
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Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04187388A (ja) * 1990-11-20 1992-07-06 Toyota Motor Corp 異種金属管の摩擦圧接方法
JPH1133747A (ja) * 1997-07-15 1999-02-09 Mori Shigeo 銅管とアルミニウム管との接合体及び接合方法
CN1959171A (zh) * 2006-09-20 2007-05-09 左铁军 无共晶组织的薄壁铜铝管焊接接头及其制备方法
CN101319741A (zh) * 2007-06-04 2008-12-10 左铁军 插接式铜铝管焊接接头及其制备方法
CN101382215A (zh) * 2007-09-05 2009-03-11 左铁军 一种带硬质套管的铜铝连接管及其制备方法
US20090078682A1 (en) * 2007-09-24 2009-03-26 Eric Feng Insertion type resistance welding method for welding copper and aluminum tubing

Family Cites Families (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH1163329A (ja) * 1997-08-22 1999-03-05 Benkan Corp 管の接続用フランジの取付方法
CN201011400Y (zh) * 2007-01-29 2008-01-23 杨连明 超长度锥度无缝管件

Patent Citations (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JPH04187388A (ja) * 1990-11-20 1992-07-06 Toyota Motor Corp 異種金属管の摩擦圧接方法
JPH1133747A (ja) * 1997-07-15 1999-02-09 Mori Shigeo 銅管とアルミニウム管との接合体及び接合方法
CN1959171A (zh) * 2006-09-20 2007-05-09 左铁军 无共晶组织的薄壁铜铝管焊接接头及其制备方法
CN101319741A (zh) * 2007-06-04 2008-12-10 左铁军 插接式铜铝管焊接接头及其制备方法
CN101382215A (zh) * 2007-09-05 2009-03-11 左铁军 一种带硬质套管的铜铝连接管及其制备方法
US20090078682A1 (en) * 2007-09-24 2009-03-26 Eric Feng Insertion type resistance welding method for welding copper and aluminum tubing

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US20170225259A1 (en) * 2014-12-09 2017-08-10 Origin Electric Company, Limited Bonded article and method for manufacturing bonded article
US9849539B2 (en) * 2014-12-09 2017-12-26 Origin Electric Company, Limited Bonded article and method for manufacturing bonded article
CN110735974A (zh) * 2018-07-20 2020-01-31 新昌县四通机电有限公司 一种管件连接结构及其制造方法、储液器、制冷系统

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