CN1959172A - Inner diameter of copper aluminum joint, copper aluminum joint with diameter being equal to inner diameter of aluminum pipe, and preparation method - Google Patents
Inner diameter of copper aluminum joint, copper aluminum joint with diameter being equal to inner diameter of aluminum pipe, and preparation method Download PDFInfo
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- CN1959172A CN1959172A CN 200610153046 CN200610153046A CN1959172A CN 1959172 A CN1959172 A CN 1959172A CN 200610153046 CN200610153046 CN 200610153046 CN 200610153046 A CN200610153046 A CN 200610153046A CN 1959172 A CN1959172 A CN 1959172A
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Abstract
A method for preparing CuAl connector with CuAl connector internal diameter being the same as internal diameter of Al tube by welding includes setting a long core shaft at internal of Cu tube forming head of core shaft by a numbers of ball form punch heads arranged from small to big, carrying out reciprocation operation for a numbers of times immediately by auxiliary push cylinder after power is switched off in order to carry out continuous punch-expansion on internal hole of connector.
Description
Technical field
The present invention relates to a kind of copper-aluminium joint internal diameter copper-aluminium joint identical and preparation method thereof, especially refrigeration system usefulness, plug-in type copper aluminum pipe welded joint with the aluminum pipe internal diameter.
Background technique
Refrigeration agent is the operation material that carries out refrigeration cycle in refrigeration plant, make of refrigeration agent in the circulating pipe system of refrigerant, refrigeration is relevant with the flow of refrigeration agent, the undergauge that causes because of technological reason in the pipeline will influence the flow velocity and the flow of refrigeration agent, finally will have influence on the product performance of refrigeration product, be very important so guarantee the internal diameter uniformity consistency of pipeline and joint.
Prior art is to be welded with the thin copper pipe of one section tube wall in the termination of the thicker aluminum pipe of tube wall, this copper pipe is identical with the external diameter of aluminum pipe, the copper pipe internal diameter is more bigger than aluminum pipe internal diameter, copper tube end closes up, and is inserted in the aluminum pipe inwall and welds, and forms copper pipe in interior, aluminum pipe telescopic lap splice outside, copper pipe reducing place this moment internal diameter is significantly less than aluminum pipe, after being installed in the refrigeration system, the refrigerant flow in the system is formed obstruction, limited the flow of refrigeration agent.In addition, in some productions such as products such as A/C evaporator and condensers, because the undergauge of joint copper pipe, cause to carry out expand tube processing, adopt the grafting joint can improve compactness although can find thus, but there is obvious undergauge phenomenon, limited copper-aluminium combined application area; In application, also find,, when crooked welded joint, be easy to tear aluminum pipe at welded joint place copper pipe end position if between the necking end of the copper pipe pipeline of grafting joint insertion portion and the aluminum pipe radial clearance is arranged.For obtaining the copper-aluminium joint internal diameter joint identical with the aluminum pipe internal diameter, at first must solve copper aluminium eutectic structure problem, eutectic structure refers to the low melting point eutectic alloy that copper aluminum metallization compound and aluminium form under the high temperature, be a kind of being highly brittle, the material that does not almost have ductility carries out enlarging to this material, will tear by weld seam, therefore, must guarantee there is not copper aluminium eutectic structure in the weld seam.
Summary of the invention
The technical problem to be solved in the present invention provides no copper aluminium eutectic structure in a kind of copper aluminum pipe weld seam, forms chemical bond in the weld seam between the copper aluminium and connects the plug-in type copper aluminum pipe joint that the copper-aluminium joint internal diameter is identical with the aluminum pipe internal diameter.
The technical problem to be solved in the present invention also relates to the pipeline reducing of the copper-aluminium joint generation of eliminating the inserting mode welding, provide the welding processing of a kind of plug-in type copper aluminium joint internal diameter copper-aluminium combined pipeline piece identical, based on the application area and the using effect of the copper aluminum pipe built-up joint structure that enlarges aluminum pipe with the aluminum pipe internal diameter.
For the copper-aluminium joint internal diameter of the present invention plug-in type copper aluminum pipe joint identical with the aluminum pipe internal diameter, the problems referred to above are to solve like this: there are straight tube-like guide portion and taper face of weld in the welded joint position of copper pipe, the external diameter of this guide portion is slightly smaller than the aluminum pipe internal diameter, forming direct chemical bond between copper pipe taper face of weld and the aluminum pipe inwall is connected, do not have eutectic structure in the weld seam, the copper-aluminium joint internal diameter is identical with the aluminum pipe internal diameter.
The principle that the present invention utilizes cold welding, resistance heating, high temperature to extend has been invented a kind of brand-new welding process, addresses the above problem.The very thin ladder undergauge straight tube-like of tube wall at first is processed into copper tube end in the present invention, copper pipe that cover is connected and aluminum pipe weld by the pressure resistance welding machine again, form the welded joint of copper-aluminium combined pipeline piece, to the ladder undergauge straight tube-like copper pipe enlarging of welded joint inside, specify as follows then:
1, get two copper aluminum pipes, at first the weld part with copper tube end is processed into the very thin undergauge ladder tubulose of tube wall, and aluminum pipe maintains the original state.Adorn a long mandrel in copper pipe inside, the head of long mandrel is made up of several ball-type drifts of arranging from small to large, and the rear suspension of mandrel is on the cylinder column of the auxiliary pushing tow cylinder of welding machine.
2, copper pipe is placed in the travelling electrode group, with the fixing copper pipe of high pressure cylinder, aluminum pipe is placed in the fixed electrode group with the fixing aluminum pipe of high pressure cylinder, the boosting cylinder will have the traveling electrode group of copper pipe and push aluminum pipe to, utilize the difference of two kinds of materials of copper aluminium on hardness, high pressure effect when inserting aluminum pipe by means of copper pipe, the oxide of aluminum pipe internal surface is cleaned out, switch on simultaneously resistance heating is carried out in the bond zone, the limit adds the flanging heating, copper pipe is constantly inner mobile to aluminum pipe in this process, it is good that welding process workpiece shift length surpasses 5mm, the copper aluminum compound (eutectic structure) that produces is extruded by high pressure, avoids fragility to organize the influence of butt joint, forms the welded joint of copper-aluminium combined pipeline piece.
3, utilize welding heat to soften copper pipe, and the good condition of plastic property of weld bead under the condition of high temperature, moment is to the undergauge copper pipe enlarging of welded joint inside after the welding.Enlarging is carried out on welding machine, and before the welding, copper-aluminium joint is under the effect of electrode cylinder, the pressure that keeps the electrode pair workpiece, the auxiliary pushing tow cylinder in welding outage back comes and goes work once immediately, and the butt joint endoporus develops continuously, finishes the final processing of butt joint.
Because the straight tube-like tube wall behind the copper pipe undergauge is very thin as previously mentioned, so the pipeline internal copper aluminium intermediate location after the processing is smooth smooth, the difference in internal diameters that is the pipeline internal diameter of taper socket plane tie and aluminum pipe is less than 2mm, with the requirement of abundant assurance refrigerant flow and subsequent machining technology.At this moment, joint internal diameter and aluminum pipe internal diameter differ very little, i.e. the copper-aluminium joint position internal diameter size 〉=φ 8.8 of the copper-aluminium joint position internal diameter size 〉=φ 8.4 of the copper-aluminium joint position internal diameter size 〉=φ 8.8 of the copper-aluminium joint position internal diameter size 〉=φ 6.8 of the copper-aluminium joint internal diameter size 〉=φ 3.0 of the copper-aluminium joint internal diameter size 〉=φ 2.8 of φ 6.0*1 aluminum pipe, φ 6.35*1 aluminum pipe, φ 9.52*1 aluminum pipe, φ 12.0*1 aluminum pipe, φ 12.0*1.2 aluminum pipe, φ 12.7*1.2 aluminum pipe.
The present invention has following characteristics: 1, utilize the difference of two kinds of materials of copper aluminium on hardness, the oxide of aluminum pipe internal surface is cleaned out in the high pressure effect when promptly utilizing copper pipe to insert aluminum pipe; 2, energising utilizes the heating of copper aluminium contact resistance to the bond zone in cleaning aluminum pipe oxide, the limit adds the flanging heating, copper pipe is constantly inner mobile to aluminum pipe under the effect of pushing tow cylinder in this process, different with the conventional, electric-resistance welding method, the workpiece shift length can surpass 5mm between the welding process copper aluminium, the copper aluminium eutectic thing that produces just produces the limit and is extruded by the high pressure between copper aluminium, avoids fragility to organize the influence of butt joint; 3, owing to copper aluminium eutectic structure in the weld seam is extruded, forming chemical bond in weld seam between the copper aluminium connects, therefore can after finishing, welding process butt joint carry out the hole enlargement processing, make through copper and aluminium welding and connect the inwall that joint, processing back copper pipe outer wall is close to aluminum pipe, aluminum pipe should not fracture after raising flow and the joint bending; 4, the copper tube end that is inserted in the aluminum pipe is processed into the very thin ladder undergauge straight tube-like of tube wall; 5, enlarging is installed on the welding equipment with mould, and the moment after welding is finished enlarging, has made full use of the bating effect of welding temperature to copper pipe; 6, the mold and punching head ladder is arranged, several drifts of ascending arrangement are arranged in the rear side of welding plug, and continuous several times progressively makes the copper pipe of necking end be close to the aluminum pipe inwall expansion of copper pipe tube wall, and the internal diameter of joint internal diameter size and aluminum pipe is approaching.
Because the straight tube-like tube wall behind the copper pipe undergauge is very thin as previously mentioned, so reducing place pipeline copper aluminium connecting part step is also not obvious, the pipe joint internal diameter that the thin segment of pipeline diameter is a welded joint and the internal diameter difference of aluminum pipe are very little, farthest guarantee refrigerant flow, and improve the joint bending properties, satisfy the requirement of subsequent machining technology.
In order further to improve welding quality, can be at metal mandrel of closing in end internal preset of copper pipe welding part, this metal mandrel is embedded in the front end of the long mandrel of enlarging mould.This plug has three effects, supports copper pipe in welding process, prevents copper pipe unstability under high pressure; Absorb heat and prevent the too high copper aluminium eutectic structure that in weld seam, produces of copper pipe temperature; Under the supporting effect of plug, copper pipe is being extruded copper aluminium eutectic structure from weld seam in the inner process that advances of aluminum pipe fully.Before welding, copper pipe is stained with clean water with metal mandrel clear water is adsorbed between metal mandrel and the copper pipe, can increase copper and aluminium welding seam cooling effect.
Welding quality of the present invention is good, the fusion face width, although adopted the socket joint type joint structure, the inside and outside caliber of joint can be accomplished basic identical with aluminum pipe to have improved the joint bending properties, has guaranteed refrigerant flow and following process structural requirement thereof.Therefore, the present invention can be used for butt joint bending properties, joint compactness, turbidity test and requires refrigeration pipe high and that flow and internal diameter are had specific (special) requirements.
Description of drawings
The invention will be further described below in conjunction with the drawings and specific embodiments.
Fig. 1 welding method schematic representation
Fig. 2 copper aluminum pipe welded joint schematic representation.
1 copper pipe, 2 long mandrel 3 traveling electrodes 4 aluminum pipes 5 fixed electrodes 6 taper faying surfaces wherein
Embodiment
A preferred embodiment of the present invention is as follows:
As Fig. 2, be inserted in the aluminum pipe after identical or close copper pipe 1 reducing of external diameter and aluminum pipe 4 and weld, form copper pipe at interior, aluminum pipe taper faying surface 6 outside, after implementing the present invention, these taper faying surface 6 places do not have copper aluminium eutectic structure, and the pipeline internal diameter φ 1 of the welded joint of formation and the internal diameter φ 2 diameter differences of aluminum pipe 2 are less than 2mm.
As Fig. 1 processing technology step: get each one of copper aluminum pipe, at first the weld part with copper pipe 1 pipe end is processed into the very thin undergauge ladder tubulose of tube wall, aluminum pipe 4 maintains the original state, copper pipe 1 is placed in the travelling electrode group 3, with the fixing copper pipe 1 of high pressure cylinder, aluminum pipe 4 is placed in the fixed electrode group 5 with the fixing aluminum pipe 4 of high pressure cylinder, the boosting cylinder will have the traveling electrode group 3 of copper pipe 1 and push aluminum pipe 4 to, utilize the difference of two kinds of materials of copper aluminium on hardness, high pressure effect when inserting aluminum pipe 4 by means of copper pipe 1, the oxide of aluminum pipe 4 internal surfaces is cleaned out, switch on simultaneously taper faying surface 6 is carried out resistance heating, the limit adds the flanging heating, constantly to aluminum pipe 4 inner moving, welding process workpiece shift length can surpass 5mm to copper pipe 1 in this process, and the copper aluminum compound (eutectic structure) of generation is extruded by high pressure, avoid fragility to organize the influence of butt joint, form the welded joint of copper-aluminium combined pipeline.Utilize welding heat to soften copper pipe, and the good condition of plastic property of weld bead under the condition of high temperature, weld of the undergauge copper pipe enlarging of back moment to welded joint inside, it is approaching with the internal diameter φ 2 of aluminum pipe to form joint internal diameter size φ 1.Since as preceding institute preceding as described in straight tube-like tube wall behind the copper pipe undergauge very thin, so the pipeline internal copper aluminium intermediate location after the processing is smooth smooth, internal diameter φ 2 difference of pipeline internal diameter φ 1 and aluminum pipe that are taper socket plane tie are less than 2mm, with the requirement of abundant assurance refrigerant flow and subsequent machining technology.
Enlarging is carried out on welding machine, weld the preceding long mandrel 2 of adorning in copper pipe inside, the head of long mandrel is made up of four ball-type drifts arranging from small to large, the rear suspension of mandrel is on the cylinder column of the auxiliary pushing tow cylinder of welding machine, copper-aluminium joint keeps the pressure of electrode pair workpiece under the effect of electrode cylinder, the auxiliary pushing tow cylinder in welding outage back comes and goes work once immediately, the butt joint endoporus develops continuously, finishes the final processing of butt joint.
The present invention selects for use the external diameter of copper pipe 1 and the aluminum pipe 2 can be identical, also can be slightly different, owing to adopted plug-in type welded joint, the present invention also to overcome the requirement for restriction of conventional method to copper aluminum pipe pipeline material wall thickness.
Therefore can be widely used in air conditioner, refrigerator, refrigerator-freezer, show cabinet, drinking machine, dehumidifier etc. has in the refrigeration product of specific (special) requirements refrigeration pipe diameter and refrigerant flow.
Claims (5)
1, the plug-in type copper aluminium joint that a kind of copper-aluminium joint internal diameter is identical with the aluminum pipe internal diameter, there is the taper faying surface at the welded joint position that it is characterized in that copper pipe, form direct chemical bond between copper pipe taper faying surface and the aluminum pipe inwall and be connected, the copper-aluminium joint internal diameter is identical with the aluminum pipe internal diameter.
2, the preparation method of the plug-in type copper aluminium joint that a kind of copper-aluminium joint internal diameter as claimed in claim 1 is identical with the aluminum pipe internal diameter, it is characterized in that at first the weld part of copper tube end is processed into the very thin undergauge ladder tubulose of tube wall, aluminum pipe maintains the original state, adorn a long mandrel in copper pipe inside, the head of long mandrel is made up of several ball-type drifts of arranging from small to large, the rear suspension of mandrel is on the cylinder column of the auxiliary pushing tow cylinder of welding machine, copper pipe is placed in the travelling electrode group, with the fixing copper pipe of high pressure cylinder, aluminum pipe is placed in the fixed electrode group with the fixing aluminum pipe of high pressure cylinder, the pushing tow cylinder will have the traveling electrode group of copper pipe and push aluminum pipe to, switch on simultaneously resistance heating is carried out in the bond zone, the limit adds the flanging heating, the auxiliary pushing tow cylinder in welding outage back comes and goes work for several times immediately, drives long mandrel butt joint endoporus and develops continuously.
3, the preparation method of the plug-in type copper aluminium joint that a kind of copper-aluminium joint internal diameter as claimed in claim 2 is identical with the aluminum pipe internal diameter is characterized in that described long mandrel front end is inlaid with one section metal mandrel.
4, the preparation method of the plug-in type copper aluminium joint that a kind of copper-aluminium joint internal diameter as claimed in claim 3 is identical with the aluminum pipe internal diameter is stained with clean water with metal mandrel with copper pipe before it is characterized in that welding clear water is adsorbed between metal mandrel and the copper pipe.
5, as the preparation method of claim 3 or the 4 described a kind of copper-aluminium joint internal diameters plug-in type copper aluminium joint identical, it is characterized in that described metal mandrel is the red copper plug with the aluminum pipe internal diameter.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006101530462A CN100420892C (en) | 2006-09-20 | 2006-09-20 | Inner diameter of copper aluminum joint, copper aluminum joint with diameter being equal to inner diameter of aluminum pipe, and preparation method |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CNB2006101530462A CN100420892C (en) | 2006-09-20 | 2006-09-20 | Inner diameter of copper aluminum joint, copper aluminum joint with diameter being equal to inner diameter of aluminum pipe, and preparation method |
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| Publication Number | Publication Date |
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| CN1959172A true CN1959172A (en) | 2007-05-09 |
| CN100420892C CN100420892C (en) | 2008-09-24 |
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Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101653860A (en) * | 2009-03-11 | 2010-02-24 | 江苏星星家电科技有限公司 | Resistance welding method for conducting and heating by utilizing resistance values of different metal materials |
| CN101319742B (en) * | 2007-06-04 | 2012-04-18 | 青岛津海制冷管业有限公司 | Pipe connection used for indoor and outdoor units of air conditioner and its method for making production method |
| CN101598251B (en) * | 2008-06-05 | 2012-05-23 | 左铁军 | Copper-aluminium joint containing canine-shaped columnar crystal structure and preparation method thereof |
| CN102528255A (en) * | 2010-12-31 | 2012-07-04 | 左铁军 | V-shaped face copper and aluminium welding processing technique and welding connector used for power cables |
| CN112672841A (en) * | 2018-09-14 | 2021-04-16 | 奥村金属株式会社 | Joint body of copper pipe and aluminum pipe and joining method thereof |
| CN116728004A (en) * | 2023-04-26 | 2023-09-12 | 安徽兴盛达制冷铜管制造有限公司 | Copper-aluminum joint preparation process and preparation device |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS5586691A (en) * | 1978-12-22 | 1980-06-30 | Hitachi Ltd | Bonding method of copper pipe and aluminum pipe |
| US5549335A (en) * | 1994-04-06 | 1996-08-27 | Peerless Of America, Incorporated | Solderless metallurgical joint |
| JPH0985467A (en) * | 1995-09-25 | 1997-03-31 | Mori Shigeo | Joined body between copper tube and aluminum tube and joining method |
| CN2677719Y (en) * | 2004-01-15 | 2005-02-09 | 左铁军 | Inserted copper alumium pipe welding joint |
| CN1299038C (en) * | 2005-02-24 | 2007-02-07 | 左铁军 | Copper-aluminium combined pipeline for refrigerating system and its preparing method |
| CN2777321Y (en) * | 2005-04-15 | 2006-05-03 | 左铁军 | Copper-aluminium composed pipeline structure parts for refrigeration system |
| CN100504251C (en) * | 2005-04-15 | 2009-06-24 | 左铁军 | Copper-aluminium combined pipeline piece with identical inner and outer diameter with aluminum pipe and manufacture process thereof |
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2006
- 2006-09-20 CN CNB2006101530462A patent/CN100420892C/en active Active
Cited By (8)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101319742B (en) * | 2007-06-04 | 2012-04-18 | 青岛津海制冷管业有限公司 | Pipe connection used for indoor and outdoor units of air conditioner and its method for making production method |
| CN101598251B (en) * | 2008-06-05 | 2012-05-23 | 左铁军 | Copper-aluminium joint containing canine-shaped columnar crystal structure and preparation method thereof |
| CN101653860A (en) * | 2009-03-11 | 2010-02-24 | 江苏星星家电科技有限公司 | Resistance welding method for conducting and heating by utilizing resistance values of different metal materials |
| CN102528255A (en) * | 2010-12-31 | 2012-07-04 | 左铁军 | V-shaped face copper and aluminium welding processing technique and welding connector used for power cables |
| WO2012089038A1 (en) * | 2010-12-31 | 2012-07-05 | Zuo Tiejun | Mobile terminal ringtone playing method and device |
| CN112672841A (en) * | 2018-09-14 | 2021-04-16 | 奥村金属株式会社 | Joint body of copper pipe and aluminum pipe and joining method thereof |
| CN116728004A (en) * | 2023-04-26 | 2023-09-12 | 安徽兴盛达制冷铜管制造有限公司 | Copper-aluminum joint preparation process and preparation device |
| CN116728004B (en) * | 2023-04-26 | 2024-03-15 | 安徽兴盛达制冷铜管制造有限公司 | Copper-aluminum joint preparation process and preparation device |
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