CN102554444A - Preparation method of combination type welded pipe and application of combination type welded pipe - Google Patents
Preparation method of combination type welded pipe and application of combination type welded pipe Download PDFInfo
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- CN102554444A CN102554444A CN2012100192892A CN201210019289A CN102554444A CN 102554444 A CN102554444 A CN 102554444A CN 2012100192892 A CN2012100192892 A CN 2012100192892A CN 201210019289 A CN201210019289 A CN 201210019289A CN 102554444 A CN102554444 A CN 102554444A
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Abstract
The invention discloses a preparation method of a combination type welded pipe and application of the combination type welded pipe. The welded pipe is formed by a copper pipe and an iron jointing part through ratio-frequency welding, and solder adopts brazing solder. The process in the invention is simple. The copper pipe and the iron jointing part are welded through the ratio-frequency welding to form the combined welded pipe which can meet the use requirements of an air condition compressor; the iron jointing part can be welded with a shell of the compressor (iron material) through electric resistance welding; particle sizes of copper crystallizers at the welding position of the copper pipe and the iron jointing part are less than 0.15; at the same time, the productive difficulty and the material cost are greatly reduced; and the environmental protection is better achieved.
Description
Technical field
The present invention relates to welding field, particularly a kind of preparation method of combined type welded tube and application.
Background technology
In the different techniques field, according to its special instructions for use, the welding manner of its product also has certain difference at present.Like existing compressor of air conditioner field, because its compressor is by compressor case 1, motor, the pump housing and reservoir are formed, and be as shown in Figure 1, and compressor case 1 is connected with reservoir through copper pipe 2.Because compressor in the running; Reason owing to its deflection axle; The vibration of axial cyclic will take place in compressor, and the part of its most fragile will be the welding position, so welding portion has tangible specification requirement (industry standard is below 0.15) to the grain size number of copper pipe 2; If grain size number is excessive, then copper pipe is prone to take place crackle and reveals during vibration of compressor.For reaching its grain size number requirement, its welding material must adopt silver solder in the existing technology, must use flame welding simultaneously.
According to Q=Cm Δ T (wherein Q is a heat, and C is a specific heat, and m is a quality, and Δ T is the temperature difference), C
FeBe 272J/g, C
CuBe 209J/g, the uniform temp iron that therefore rises needs more heat.According to Q=I 2Rt (wherein Q is a heat, and I is an electric current, and R is a resistance, and t is heat time heating time), for specific firing equipment, the heat in the identical time is certain, and hence one can see that, and the iron of rising uniform temp equal quality needs longer heat time heating time.
When welding, copper-iron and scolder should be as far as possible at uniform temps.Because the fusing point of copper pipe is about 1000 ℃, the fusing point of spelter solder also is between 900 ℃～1000 ℃, as adopting spelter solder; Its welding temperature is too high, simultaneously because the big sheet material of shell 1 volume is thicker, and therefore cause copper-its heat time heating time will be very long when iron welded; Cause the grain size number of copper pipe to require to be difficult to guarantee; Therefore must adopt and the copper pipe fusing point differs silver solder (silver content is more than 34%, and fusing point is about 730 ℃) far away as its welding material, but its material cost is higher.Must use flame welding simultaneously, can comparatively fast heat up, and can heat iron shell earlier.But need to adopt the flame welding, the temperature around its welding is very high, causes environment temperature higher, in the gas of its generation simultaneously very major part be CO
2, cause environmental pressure also bigger.Because of welding equipment is limit; Its welding temperature curve is generally as shown in Figure 2: preheating (is generally 10 second) more than 7 seconds at least just can reach the welding temperature that is higher than 30～50 ℃ of scolder melting temperatures; Need keep this welding temperature more than at least 5 seconds (be generally 5-15 second) to weld then, last air-cooled more than at least 6.5 seconds.
The combined type welded tube that is made by unlike material is also arranged at present, but because conditions such as technology are limit, the copper grain size number of its welding position is about about 0.3 generally greater than 0.15, therefore can't be applicable to the compressor of air conditioner field.
Summary of the invention
For overcoming shortcoming of the prior art, the invention provides a kind of preparation method of combined type welded tube, its welded tube that makes can meet the instructions for use of compressor of air conditioner, and greatly reduces production difficulty and cost, and more environmental protection.
In order to solve the problems of the technologies described above, the present invention realizes through following technical scheme: a kind of preparation method of combined type welded tube is characterized in that: said welded tube is welded through ratio-frequency welding by copper pipe and iron connecting parts, and scolder adopts spelter solder.
The temperature curve of described ratio-frequency welding welding is: be preheated to the welding temperature that is higher than 30～50 ℃ of scolder melting temperatures in 6 seconds, keep this welding temperature in 3 seconds, to accomplish welding then, then through 6 seconds with the interior air-cooled water-cooled of carrying out at last.
Described copper pipe and iron connecting parts carry out preheating, welding, air cooling step in the atmosphere of reducibility gas or protective gas.
After the described water-cooled, also be provided with tempering step, temperature is 350～450 ℃, and the time is 2-2.5 hour and carries out in the atmosphere of reducibility gas or protective gas.
Described iron connecting parts is circular or annular slice, is sheathed on outside the copper pipe end, and copper pipe end flushes or protrude in iron connecting parts bottom surface with iron connecting parts bottom surface; Or the iron connecting parts is tubulose, its port outer wall and the welding of copper pipe end inwall; Or the iron connecting parts is tubulose, its port inner wall and the welding of copper pipe end outer wall.
When described iron connecting parts was circular, its lateral surface was provided with the gradient; When said iron connecting parts was tubulose, end turned up to handle and forms flange, and both inwalls are in same plane after copper pipe and the welding of iron connecting parts.
Said ratio-frequency welding adopts the induction of high frequency weldering, and said welded tube is from the heating region of the direction insertion high-frequency induction welder heating tube of iron connecting parts, till the welding position of iron connecting parts and copper pipe gets into heating region.
By the combined type welded tube that above-mentioned preparation method makes, the copper grain size number of the welding position of iron connecting parts and copper pipe is less than 0.15.
The compressor of air conditioner that includes combinations thereof formula welded tube.
The welding position of described compressor case is provided with boss, and boss has the identical inclined-plane of iron connecting parts lateral surface angle with the combined welding pipe.
Technology of the present invention is simple; Through ratio-frequency welding copper pipe and iron connecting parts are welded together to form the combined type welded tube; Make its instructions for use that can meet compressor of air conditioner, iron connecting parts part can be taked electric resistance welding and compressor case (iron material matter) welding, and the copper grain size number of the position, welding position of copper pipe and iron connecting parts is less than 0.15; Greatly reduce production difficulty and material cost simultaneously, and more environmental protection.
Description of drawings
Below in conjunction with the accompanying drawing and the specific embodiment the present invention is done further detailed explanation.
Fig. 1 be in the prior art compressor case and copper pipe be connected sketch map;
Fig. 2 is the compressor case of prior art and the temperature profile that copper pipe adopts silver solder to weld through flame welding;
Fig. 3 is the sketch map of the combined type welded tube of embodiment 1 when preparing;
Fig. 4 is the temperature profile that adopts spelter solder to weld through ratio-frequency welding between copper pipe and the iron connecting parts of electrical resistance welding tube of the present invention;
Fig. 5-Fig. 8 is respectively the profile of the combined type welded tube of embodiment of the invention 1-4;
Fig. 9, Figure 10 are respectively two kinds of use scheme of installations of the combined type welded tube of embodiment 1;
Figure 11 is the use scheme of installation of the combined type welded tube of embodiment 2;
Figure 12, Figure 13 are respectively two kinds of use scheme of installations of the combined type welded tube of embodiment 3.
The specific embodiment
The present invention is a kind of preparation method of combined type welded tube, and said combined type welded tube 3 is welded through ratio-frequency welding by copper pipe 31 and iron connecting parts 32.Because the thickness of copper pipe 31 and iron connecting parts 32 is all very thin, adopt the ratio-frequency welding welding simultaneously, can realize being rapidly heated, even adopt spelter solder, copper-iron and scolder can both rise to welding temperature very soon.Scolder adopts spelter solder (fusing point is about 820～930 ℃), greatly reduces the material cost that prior art is used silver solder.As shown in Figure 4; Temperature curve when adopting the ratio-frequency welding welding is: be preheated to the welding temperature that is higher than 30～50 ℃ of scolder melting temperatures in 6 seconds; Keep welding temperature in 3 seconds, to accomplish welding then, then through 6 seconds with interior air-cooled, carry out water-cooled at last to prevent that the copper crystallization from continuing to increase.The time of whole technology shortens greatly, has especially shortened preheating time (foreshortening in 5 seconds) and weld interval (foreshortening in 3 seconds), thereby the grain size number of realization copper is less than 0.15.Wherein, compare with existing temperature curve shown in Figure 2, α 3＞α 1, α 4＞α 2 explains that heating rate of the present invention is faster.
Preferably, copper pipe 31 carries out steps such as preheating, welding, air cooling with iron connecting parts 32 in the atmosphere of reducibility gas or protective gas (like nitrogen), oxidized to prevent copper material.For eliminating the internal stress of combined type welded tube 3, preferred, after water-cooled, be provided with tempering step, temperature is 350～450 ℃, the time is 2-2.5 hour and carries out in the atmosphere of reducibility gas or protective gas (like nitrogen).
Said ratio-frequency welding adopts the induction of high frequency weldering.Preferably, as shown in Figure 3, combined type welded tube 3 inserts the heating region of the medium-high frequency heating tube 61 of high-frequency induction welder 6 from the direction of iron connecting parts 32; Till the welding position of iron connecting parts 32 and copper pipe 31 gets into heating region just fully; Adopt this mode, the iron connecting parts 32 that specific heat is bigger at first is heated, and the less copper pipe 31 of specific heat is delayed slightly and is heated; Make iron, copper and the spelter solder of welding position to reach uniform temp in the identical time; To shorten the heat time heating time of copper pipe 31 as far as possible, avoid grain size number to increase better effects if.
By the combined type welded tube 3 that above-mentioned preparation method makes, the copper grain size number of the welding position of iron connecting parts 32 and copper pipe 31 meets the instructions for use of compressor of air conditioner less than 0.15, therefore can be widely used in compressor of air conditioner.
As shown in Figure 5, iron connecting parts 32 is circular, is sheathed on outside copper pipe 31 ports, and both are through the fixing combined type welded tube 3 that forms of ratio-frequency welding welding.Iron connecting parts 32 lateral surfaces are provided with the gradient, so that weld with compressor case 1.
During preparation, as shown in Figure 3, iron connecting parts 32 is circular, outside the spelter solder ring is sheathed on copper pipe 31 ports.Copper pipe 31 ports flush with iron connecting parts 32 bottom surfaces, and more preferably copper pipe 31 ports protrude in the bottom surface of iron connecting parts 32, only otherwise with compressor in the motor touching all can, can further reduce the generation of eddy current.Whole combined type welded tube 3 supports are on welding saddle 61, and welding saddle 61 hollows are provided with nitrogen input channel and combined type welded tube 3 internal communication.Combined type welded tube 3 is outer to be covered with the protective gas cover 63 processed by insulating materials; Protective gas cover 63 tops are provided with the stopper 64 of band nitrogen input channel; Protective gas cover 63 bottoms are provided with nitrogen outlet; Thereby all be under the protection of nitrogen atmosphere inside and outside making combined type welded tube 3, to prevent that copper is by high-temperature oxydation.Combined type welded tube 3 is from the heating region of the medium-high frequency heating tube 61 of the direction insertion high-frequency induction welder 6 of iron connecting parts 32, till the welding position of iron connecting parts 32 and copper pipe 31 gets into heating region just fully.
Adopting fusing point in the present embodiment is 870 ℃ spelter solder; Temperature curve during the ratio-frequency welding welding is: about 3 seconds to 650 ℃ of preheatings; In 1 second, be rapidly heated then to 900 ℃; Keep this temperature to accomplish welding in 2 seconds then, temperature was reduced to about 600-700 ℃, carry out water-cooled at last in air-cooled then 3 seconds.Carry out tempering after the water-cooled, temperature is 400 ℃, and the time is 2 hours.
As shown in Figure 9; The welding position edge protuberance of compressor case 1 forms boss; Boss has the identical inclined-plane of iron connecting parts lateral surface angle with the combined welding pipe, thereby realizes electric resistance welding, the raising weld strength so that form between combined type welded tube and boss perfectly to cooperate.The combined type welded tube 3 that makes is installed on 1 last time of compressor case; Combined type welded tube 3 through upper and lower anchor clamps 4,5 clampings after; Through electric resistance welding, the boss inwall of compressor case 1 welding position of iron connecting parts 32 lateral surfaces and irony is realized the face exposure to welding fixed.Perhaps shown in figure 10, compressor case 1 installing hole edge does not have the boss of setting, through electric resistance welding, and iron connecting parts 32 direct and compressor case 1 installing hole inwall realization point exposures to welding fixed.Face contact welding effect shown in Figure 9 is superior to some contact welding shown in Figure 10.
Embodiment 2
As shown in Figure 6, iron connecting parts 32 is an annular slice, is sheathed on outside copper pipe 31 ports, and copper pipe 31 ports flush with iron connecting parts 32 bottom surfaces, or protrude in the bottom surface of iron connecting parts 32.Both are through the fixing combined type welded tube 3 that forms of ratio-frequency welding welding, and welding procedure is with embodiment 1.Be installed on 1 last time of compressor case, shown in figure 11, through electric resistance welding, the compressor case 1 installing hole end face of iron connecting parts 32 bottom surfaces and irony is realized the face exposure to welding fixed.
As shown in Figure 7, iron connecting parts 32 is a tubulose, and its port outer wall and copper pipe 31 port inner walls are through the ratio-frequency welding welding, and welding procedure is with embodiment 1.Be better and compressor case welding, iron connecting parts 32 ends turn up to handle and form flange, and valgus angle is less than 90 °.Preferably, the valgus angle of flange is 30 °～60 °.Avoid the generation of eddy current for the inner wall smooth non-resistance that makes combined type welded tube 3, copper pipe 31 ports extend out, make iron connecting parts 32 and the welding of copper pipe 31 port inner walls after, both inwalls are in same plane.
Be installed on 1 last time of compressor case, shown in figure 13, compressor case 1 welding position edge protuberance forms boss, through electric resistance welding, with the compressor case 1 installing hole boss inwall realization face exposure to welding fixed of iron connecting parts 32 lateral surfaces and irony.Perhaps shown in figure 12, compressor case 1 installing hole edge does not have the boss of setting, through electric resistance welding, and iron connecting parts 32 direct and compressor case 1 installing hole inwall realization point exposures to welding fixed.Face contact welding effect shown in Figure 13 is superior to some contact welding shown in Figure 12.
Embodiment 4
As shown in Figure 8, iron connecting parts 32 is a tubulose, and its port inner wall and copper pipe 31 port outer walls are through the ratio-frequency welding welding, and welding procedure is with embodiment 1.Be better and compressor case welding, iron connecting parts 32 ends turn up to handle and form flange, and valgus angle is less than 90 °.Preferably, the valgus angle of flange is 30 °～60 °.Avoid the generation of eddy current for the inner wall smooth non-resistance that makes combined type welded tube 3, iron connecting parts 32 ports extend out, make the welding of copper pipe 31 ports and iron connecting parts 32 inwalls after, both inwalls are in same plane.
Be installed on 1 last time of compressor case with embodiment 3.
Claims (10)
1. the preparation method of a combined type welded tube, it is characterized in that: said welded tube is welded through ratio-frequency welding by copper pipe and iron connecting parts, and scolder adopts spelter solder.
2. the preparation method of combined type welded tube according to claim 1; It is characterized in that: the temperature curve of described ratio-frequency welding welding is: be preheated to the welding temperature that is higher than 30～50 ℃ of scolder melting temperatures in 6 seconds; Keep this welding temperature in 3 seconds, to accomplish welding then, then through 6 seconds with the interior air-cooled water-cooled of carrying out at last.
3. the preparation method of combined type welded tube according to claim 2 is characterized in that: described copper pipe and iron connecting parts carry out preheating, welding, air cooling step in the atmosphere of reducibility gas or protective gas.
4. the preparation method of combined type welded tube according to claim 2 is characterized in that: after the described water-cooled, also be provided with tempering step, temperature is 350～450 ℃, and the time is 2-2.5 hour and carries out in the atmosphere of reducibility gas or protective gas.
5. according to the preparation method of the described combined type welded tube of arbitrary claim among the claim 1-4; It is characterized in that: described iron connecting parts is circular or annular slice; Be sheathed on outside the copper pipe end, copper pipe end flushes or protrudes in iron connecting parts bottom surface with iron connecting parts bottom surface; Or the iron connecting parts is tubulose, its port outer wall and the welding of copper pipe end inwall; Or the iron connecting parts is tubulose, its port inner wall and the welding of copper pipe end outer wall.
6. the preparation method of combined type welded tube according to claim 5 is characterized in that: when described iron connecting parts was circular, its lateral surface was provided with the gradient; When said iron connecting parts was tubulose, end turned up to handle and forms flange, and both inwalls are in same plane after copper pipe and the welding of iron connecting parts.
7. the preparation method of combined type welded tube according to claim 5; It is characterized in that: said ratio-frequency welding adopts the induction of high frequency weldering; Said welded tube is from the heating region of the direction insertion high-frequency induction welder heating tube of iron connecting parts, till the welding position of iron connecting parts and copper pipe gets into heating region.
8. the combined type welded tube that is made by the said preparation method of arbitrary claim among the claim 1-7, the copper grain size number of the welding position of iron connecting parts and copper pipe is less than 0.15.
9. the compressor of air conditioner that includes the said combined type welded tube of claim 8.
10. compressor of air conditioner according to claim 9; Comprise compressor case and combined type welded tube; It is characterized in that: the welding position of described compressor case is provided with boss, and boss has the identical inclined-plane of iron connecting parts lateral surface angle with the combined welding pipe.
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| Application Number | Priority Date | Filing Date | Title |
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| CN201210019289.2A CN102554444B (en) | 2012-01-20 | 2012-01-20 | Preparation method of combination type welded pipe and application of combination type welded pipe |
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| CN201210019289.2A CN102554444B (en) | 2012-01-20 | 2012-01-20 | Preparation method of combination type welded pipe and application of combination type welded pipe |
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| CN102554444A true CN102554444A (en) | 2012-07-11 |
| CN102554444B CN102554444B (en) | 2014-04-30 |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103143799A (en) * | 2013-03-12 | 2013-06-12 | 嵊州市致远焊接制品有限公司 | Processing technology of connecting pipe fitting |
| CN104439732A (en) * | 2014-12-10 | 2015-03-25 | 斯培淦 | Novel welding structure and welding method |
| CN104668762A (en) * | 2013-12-03 | 2015-06-03 | （株）东熙产业 | Combination method of fuel tank and pipe |
| CN113059259A (en) * | 2021-04-06 | 2021-07-02 | 合肥邦立电子股份有限公司 | High-frequency digital induction welding device and method for liquid level sensor |
| CN114251267A (en) * | 2021-12-06 | 2022-03-29 | 广东美芝制冷设备有限公司 | A casing and compressor for compressor |
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| JPS6179879A (en) * | 1984-09-27 | 1986-04-23 | Toshiba Corp | Compressor |
| JPS648377A (en) * | 1987-06-29 | 1989-01-12 | Toshiba Corp | Enclosed type compressor |
| CN2801367Y (en) * | 2005-04-12 | 2006-08-02 | 上海恒精机电设备有限公司 | Copper-steel deposited welding machine |
| CN101230860A (en) * | 2008-01-24 | 2008-07-30 | 广东美芝制冷设备有限公司 | Exhaust tube for air-conditioner compressor as well as manufacturing and assembling method thereof |
| CN102305502A (en) * | 2011-08-18 | 2012-01-04 | 佛山市胜安制冷配件有限公司 | Air inlet and outlet pipe for air conditioner accessory |
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Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
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| JPS6179879A (en) * | 1984-09-27 | 1986-04-23 | Toshiba Corp | Compressor |
| JPS648377A (en) * | 1987-06-29 | 1989-01-12 | Toshiba Corp | Enclosed type compressor |
| CN2801367Y (en) * | 2005-04-12 | 2006-08-02 | 上海恒精机电设备有限公司 | Copper-steel deposited welding machine |
| CN101230860A (en) * | 2008-01-24 | 2008-07-30 | 广东美芝制冷设备有限公司 | Exhaust tube for air-conditioner compressor as well as manufacturing and assembling method thereof |
| CN102305502A (en) * | 2011-08-18 | 2012-01-04 | 佛山市胜安制冷配件有限公司 | Air inlet and outlet pipe for air conditioner accessory |
Cited By (6)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103143799A (en) * | 2013-03-12 | 2013-06-12 | 嵊州市致远焊接制品有限公司 | Processing technology of connecting pipe fitting |
| CN103143799B (en) * | 2013-03-12 | 2015-07-08 | 嵊州市致远焊接制品有限公司 | Processing technology of connecting pipe fitting |
| CN104668762A (en) * | 2013-12-03 | 2015-06-03 | （株）东熙产业 | Combination method of fuel tank and pipe |
| CN104439732A (en) * | 2014-12-10 | 2015-03-25 | 斯培淦 | Novel welding structure and welding method |
| CN113059259A (en) * | 2021-04-06 | 2021-07-02 | 合肥邦立电子股份有限公司 | High-frequency digital induction welding device and method for liquid level sensor |
| CN114251267A (en) * | 2021-12-06 | 2022-03-29 | 广东美芝制冷设备有限公司 | A casing and compressor for compressor |
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| CN102554444B (en) | 2014-04-30 |
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