Pipeline connection structure and compressor assembly

Abstract

The present invention provides a pipeline connection structure and a compressor assembly. The pipeline connection structure includes a first steel pipe, a first copper sleeve, a second steel pipe, and a second copper sleeve. Each of the first steel pipe, the first copper sleeve, the second steel pipe, and the second copper sleeve includes an upper section and a lower section. The first copper sleeve is sleeved on the upper section of the first steel pipe, and the upper section of the first copper sleeve extends beyond the upper section of the first steel pipe to form a first extension section. The second copper sleeve is sleeved on the upper section of the second steel pipe. The first steel pipe is welded to the first copper sleeve, and the second steel pipe is welded to the second copper sleeve. The first extension section of the first copper sleeve is sleeved outside the second copper sleeve and welded to the second copper sleeve. According to the pipeline connection structure of the first aspect embodiment of the present invention, by reasonably setting the positional relationship of the first steel pipe, the first copper sleeve, the second steel pipe, and the second copper sleeve, the thickness of the first copper sleeve is not limited, the strength of the joint of the pipeline connection structure is increased, the risks of pipeline fracture and leakage are reduced, and the reliability of the pipeline connection structure is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electrical appliance manufacturing, and particularly to a pipeline connection structure and a compressor assembly. Background Art

[0002] In the related art, there are multiple pipelines provided inside a compressor, and the pipelines are connected to each other through a pipeline connection structure. The strength of steel pipes with the same specification is much greater than that of copper pipes, and the thermal conductivity of copper is many times that of stainless steel. During soldering, the steel pipes are prone to uneven heat absorption, resulting in cracking or a reduction in strength due to thermal stress. To ensure the feasibility and convenience of on-site welding, generally a copper sleeve is added at the joint of the steel pipe. The copper sleeve is pre-welded to the steel pipe as a whole, and during on-site soldering in the workshop, only the copper sleeves are soldered to each other, or the copper sleeve is soldered to the copper pipe, etc. However, there are various welding defects in the existing pipeline connection structure. Summary of the Invention

[0003] The present invention is made based on the inventor's discovery and recognition of the following facts and problems:

[0004] In the related art, such as Figure 1 and Figure 2 , in the pipeline connection structure, one copper sleeve is welded outside the end of one steel pipe, and the other copper sleeve is welded inside the other steel pipe. During connection, the two copper sleeves are welded. If the flared or tapered copper sleeve welding method is adopted, the transition area of the flared or tapered part of the copper sleeve is close to the weld. Under the dual influence of welding heat and high-speed flame, the crystal grains at this place become larger after welding, and there is thermal stress, resulting in a decrease in strength, making this place the weak point of the joint.

[0005] In the related art, such as Figure 3 and Figure 4 , if the copper sleeve welding method with flush ports is adopted, it is not easy to observe the temperature state of the copper sleeve during welding, the solder is difficult to adhere to the weld, which easily leads to overheating of the weld, affecting the strength of the copper sleeve - steel pipe weld, and the weld is prone to leakage. In addition, the steel pipe exposed to the welding torch flame on the outside is prone to cracking and a decrease in strength under the condition of uneven heating, and is greatly affected by the welding level, with poor welding consistency. The outer steel pipe turns black after being heated, forming a contrast with the color of the matrix.

[0006] In the related art, such as Figure 5 , the melting points of copper and steel differ greatly. During flame welding, the excess solder will drip onto the inner wall of the steel pipe and slide down like water droplets. The sliding solder will enter components such as the four-way valve, easily causing the jamming or abnormal noise of the internal sliding components.

[0007] The present invention aims to solve at least one of the technical problems in the related art to a certain extent.

[0008] To this end, the first object of the present invention is to propose a pipeline connection structure.

[0009] The second object of the present invention is to propose another pipeline connection structure.

[0010] The third object of the present invention is to propose a compressor assembly.

[0011] The pipeline connection structure according to the embodiment of the first aspect of the present invention includes a first steel pipe, a first copper sleeve, a second steel pipe, and a second copper sleeve. The first steel pipe includes an upper section of the first steel pipe and a lower section of the first steel pipe. The second steel pipe includes an upper section of the second steel pipe and a lower section of the second steel pipe. The first copper sleeve includes an upper section of the first copper sleeve and a lower section of the first copper sleeve. The second copper sleeve includes an upper section of the second copper sleeve and a lower section of the second copper sleeve. The first copper sleeve is sleeved on the upper section of the first steel pipe, and the upper section of the first copper sleeve extends beyond the upper section of the first steel pipe to form a first extension section. The second copper sleeve is sleeved on the lower section of the second steel pipe. The first steel pipe is welded to the first copper sleeve, and the second steel pipe is welded to the second copper sleeve. The first extension section of the first copper sleeve is sleeved outside the second copper sleeve and welded to the second copper sleeve.

[0012] For the pipeline connection structure according to the embodiment of the first aspect of the present invention, by reasonably setting the positional relationship of the first steel pipe, the first copper sleeve, the second steel pipe, and the second copper sleeve, the thickness of the first copper sleeve is not limited, the strength of the joint of the pipeline connection structure is increased, the risks of pipeline fracture and leakage are reduced, and the reliability of the pipeline connection structure is improved.

[0013] In some embodiments, the lower section of the second copper sleeve extends beyond the lower section of the second steel pipe to form a second extension section or is flush with the lower section of the second steel pipe, and the upper section of the second copper sleeve extends out of the upper section of the first copper sleeve by a predetermined length.

[0014] In some embodiments, the first steel pipe or the first copper sleeve is a through-diameter pipe or a stepped pipe.

[0015] In some embodiments, the end face of the lower section of the second copper sleeve abuts against or is spaced from the end face of the upper section of the first steel pipe.

[0016] In some embodiments, the lower section of the second copper sleeve extends into the first steel pipe.

[0017] In some embodiments, a positioning protrusion for blocking the lower section of the second copper sleeve is provided on the inner wall of the first steel pipe.

[0018] In some embodiments, the upper section of the first steel pipe is flared or tapered.

[0019] The pipeline connection structure according to the second aspect embodiment of the present invention includes a first pipe, a second pipe, and a third copper sleeve. The first pipe is a copper pipe or a copper-plated pipe, the second pipe is a steel pipe, and the third copper sleeve is sleeved outside the lower section of the second pipe and welded to the second pipe. The upper section of the first pipe is sleeved outside the third copper sleeve and welded to the third copper sleeve.

[0020] In some embodiments, the upper section of the third copper sleeve extends out from the lower section of the second pipe. The upper section of the first pipe is enlarged to form a transition section, and a filter pressing ring is provided between the lower section of the second pipe and the transition section of the first pipe.

[0021] The compressor assembly according to the third aspect embodiment of the present invention applies the pipeline connection structure in the above embodiments. Brief Description of the Drawings

[0022] Figures 1 - 5 It is a schematic structural diagram of the pipeline connection structure in the related art;

[0023] Figure 6 It is a schematic structural diagram of the first steel pipe and the first copper sleeve in the pipeline connection structure according to the first aspect embodiment of the present invention;

[0024] Figure 7 It is a schematic structural diagram of the first steel pipe and the first copper sleeve in the pipeline connection structure according to another embodiment of the present invention;

[0025] Figure 8 It is a schematic structural diagram of the first steel pipe and the first copper sleeve in the pipeline connection structure according to another embodiment of the present invention;

[0026] Figure 9 It is a schematic structural diagram of the second steel pipe and the second copper sleeve in the pipeline connection structure according to the embodiment of the present invention;

[0027] Figure 10 It is a schematic structural diagram of the second steel pipe and the second copper sleeve in the pipeline connection structure according to another embodiment of the present invention;

[0028] Figure 11 It is a schematic structural diagram of the pipeline connection structure according to the embodiment of the present invention;

[0029] Figure 12 It is a schematic structural diagram of the pipeline connection structure according to another embodiment of the present invention;

[0030] Figure 13 It is a schematic structural diagram of the pipeline connection structure according to another embodiment of the present invention;

[0031] Figure 14 It is a schematic structural diagram of the pipeline connection structure according to another embodiment of the present invention;

[0032] Figure 15 It is a schematic structural diagram of a pipeline connection structure according to an embodiment of the second aspect of the present invention.

[0033] Reference numerals:

[0034] 11. First steel pipe; 11A. Upper section of the first steel pipe; 11B. Lower section of the first steel pipe; 111. Positioning protrusion; 12. First copper sleeve; 12A. Upper section of the first copper sleeve; 12B. Lower section of the first copper sleeve; 21. Second steel pipe; 21A. Upper section of the second steel pipe; 21B. Lower section of the second steel pipe; 22. Second copper sleeve; 22A. Upper section of the second copper sleeve; 22B. Lower section of the second copper sleeve; 31. First pipe; 41. Second pipe; 41B. Lower section of the second pipe; 42. Third copper sleeve; 5. Filter screen pressing ring. Detailed implementation manners

[0035] The embodiments of the present invention will be described in detail below. The examples of the embodiments are shown in the accompanying drawings. The embodiments described below with reference to the accompanying drawings are exemplary and are intended to explain the present invention, and should not be construed as a limitation to the present invention.

[0036] Refer to Figures 6 - 15 to describe the pipeline connection structure according to the embodiment of the first aspect of the present invention.

[0037] As Figures 6 - 10 shown, the pipeline connection structure according to the embodiment of the first aspect of the present invention includes a first steel pipe 11, a first copper sleeve 12, a second steel pipe 21, and a second copper sleeve 22. The first steel pipe 11 has an upper section 11A and a lower section 11B of the first steel pipe. The second steel pipe 21 has a lower section 21B and an upper section 21A of the second steel pipe. The first copper sleeve 12 has an upper section 12A and a lower section 12B of the first copper sleeve. The second copper sleeve 22 has a lower section 22B and an upper section 22A of the second copper sleeve.

[0038] As Figures 6 - 8 shown, the first copper sleeve 12 is sleeved on the outer peripheral surface of the upper section 11A of the first steel pipe. In the figure, the upper section 12A of the first copper sleeve is located at the upper part, the lower section 12B of the first copper sleeve is located at the lower part, the upper section 11A of the first steel pipe is located at the upper part, and the lower section 11B of the first steel pipe is located at the lower part. The upper section 12A of the first copper sleeve extends beyond the upper section 11A of the first steel pipe to form a first extension section.

[0039] As Figure 9 and Figure 10 shown, the second copper sleeve 22 is sleeved on the lower section 21B of the second steel pipe.

[0040] As Figures 11 - 14 shown, the first steel pipe 11 and the first copper sleeve 12 are welded into one body, the second steel pipe 21 and the second copper sleeve 22 are welded into one body, and the first extension section of the first copper sleeve 12 is sleeved outside the second copper sleeve 22 and welded to the second copper sleeve 22.

[0041] According to the pipeline connection structure of the first aspect embodiment of the present invention, by reasonably setting the positional relationship of the first steel pipe 11, the first copper sleeve 12, the second steel pipe 21 and the second copper sleeve 22, both the first copper sleeve 12 and the second copper sleeve 22 are arranged outside the steel pipe, avoiding disadvantages such as poor heat conduction ability of the steel pipe and uneven heat absorption and cracking. In addition, since the first copper sleeve 12 is arranged outside the first steel pipe 11, the thickness of the first copper sleeve 12 is not limited, increasing the strength of the joint of the pipeline connection structure, reducing the risk of pipeline fracture and leakage risk, and improving the reliability of the pipeline connection structure.

[0042] In some embodiments, as Figure 9 and Figure 10 shown, the lower section 22B of the second copper sleeve is located at the lower part, and the upper section 22A of the second copper sleeve is located at the upper part. The lower section 21B of the second steel pipe is located at the lower part, and the upper section 21A of the second steel pipe is located at the upper part. As Figure 9 shown, the lower section 22B of the second copper sleeve is flush with the lower section 21B of the second steel pipe, or as Figure 10 shown, the lower section 22B of the second copper sleeve extends beyond the lower section 21B of the second steel pipe to form a second extension section. The upper section 22A of the second copper sleeve extends a predetermined length from the upper section 12A of the first copper sleeve.

[0043] Extending the lower section 22B of the second copper sleeve beyond the lower section 21B of the second steel pipe has a larger solder penetration depth and better sealing performance compared with the lower section 22B of the second copper sleeve being flush with the lower section 21B of the second steel pipe, and can avoid the problem of excess solder dripping.

[0044] Furthermore, the predetermined length is 15 - 25 millimeters, and the length of the first extension section is 8 - 12 millimeters. Thus, it can be ensured that the upper section 22A of the second copper sleeve can exceed the upper section 12A of the first copper sleeve, avoiding the appearance of a cavity inside the upper section 12A of the first copper sleeve and affecting the structural strength of the connection part. At the same time, the upper section 22A of the second copper sleeve can protect the lower section 21B of the second steel pipe, preventing solder from dripping onto the lower section 21B of the second steel pipe and thus affecting the structural strength of the lower section 21B of the second steel pipe.

[0045] In some embodiments, as Figure 10 shown, the end face of the lower section 22B of the second copper sleeve abuts against the end face of the upper section 11A of the first steel pipe; or as Figure 11 and Figure 12 shown, the end face of the lower section 22B of the second copper sleeve is spaced a predetermined distance from the end face of the upper section 11A of the first steel pipe. Thus, the required connection method can be adjusted according to the actual working conditions.

[0046] In some embodiments, as Figure 14 shown, the lower section 22B of the second copper sleeve extends into the first steel pipe 11. Thus, this structure can form multiple layers of protection and strengthen the structural strength of the connection part.

[0047] Furthermore, when the lower section 22B of the second copper sleeve extends into the first steel pipe 11, in order to ensure the relative position between the second copper sleeve 22 and the first steel pipe 11, a positioning protrusion 111 for stopping the lower section 22B of the second copper sleeve is provided on the inner wall of the first steel pipe 11. The lower section 22B of the second copper sleeve extends into the first steel pipe 11 and gradually extends until the end face of the lower section 22B of the second copper sleeve contacts the positioning protrusion 111 on the inner wall of the first steel pipe 11, making it impossible for the second copper sleeve 22 to continue extending, thus ensuring the relative position between the second copper sleeve 22 and the first steel pipe 11.

[0048] In some embodiments, as Figure 6 and Figure 7 shown, the upper section 11A of the first steel pipe expands or contracts, and a flared or tapered opening is provided in the upper section 11A of the first steel pipe, which can reduce the influence of the welding part on the lower section 11B of the first steel pipe.

[0049] Or, as Figure 8 shown, the radial dimension of the upper section 11A of the first steel pipe is uniform. Thus, compared with the flared and tapered opening methods, the uniform dimension can save the material processing cost. The following refers to Figure 15 to describe the pipeline connection structure of the second aspect embodiment of the present invention.

[0050] As Figure 15 shown, according to the pipeline connection structure of the second aspect embodiment of the present invention, it includes a first pipe 31, a second pipe 41 and a third copper sleeve 42. The first pipe 31 is a copper pipe or a copper-plated pipe, the second pipe 41 is a steel pipe, the third copper sleeve 42 is sleeved outside the lower section 41B of the second pipe and welded to the second pipe 41, and the upper section of the first pipe 31 is sleeved outside the third copper sleeve 42 and welded to the third copper sleeve 42. Thus, using one copper sleeve to connect two steel pipes can reduce the processing steps and save raw materials.

[0051] In some embodiments, the lower section of the third copper sleeve 42 extends out of the lower section 41B of the second pipe, the upper section of the first pipe 31 expands to form a transition section, and a filter screen pressing ring 5 is provided between the lower section 41B of the second pipe and the transition section of the first pipe 31. The pipeline connection structure in this embodiment can cooperate with the return air pipe filter screen in the compressor by setting the filter screen pressing ring 5, and can prevent the solder from falling into the compressor.

[0052] The compressor assembly according to the third aspect embodiment of the present invention applies the pipeline connection structure in the above-mentioned embodiment.

[0053] The following refers to Figures 6 - 15 to describe the pipeline connection structure according to the embodiment of the present invention. It can be understood that the following description is only an exemplary illustration and not a specific limitation of the invention.

[0054] Embodiment 1:

[0055] In this embodiment, as Figure 11 shown, the pipeline connection structure includes a first steel pipe 11, a first copper sleeve 12, a second steel pipe 21, and a second copper sleeve 22. The first steel pipe 11 has an upper section 11A and a lower section 11B of the first steel pipe. The second steel pipe 21 has a lower section 21B and an upper section 21A of the second steel pipe. The first copper sleeve 12 has an upper section 12A and a lower section 12B of the first copper sleeve. The second copper sleeve 22 has a lower section 22B and an upper section 22A of the second copper sleeve. The first copper sleeve 12 is sleeved outside the upper section 11A of the first steel pipe. In the figure, the upper section 12A of the first copper sleeve is located at the upper part, the lower section 12B of the first copper sleeve is located at the lower part, the upper section 11A of the first steel pipe is located at the upper part, and the lower section 11B of the first steel pipe is located at the lower part. The upper section 12A of the first copper sleeve extends beyond the upper section 11A of the first steel pipe to form a first extension section. The second copper sleeve 22 is sleeved on the lower section 21B of the second steel pipe. The first steel pipe 11 and the first copper sleeve 12 are welded together. The second steel pipe 21 and the second copper sleeve 22 are welded together. The first extension section of the first copper sleeve 12 is sleeved outside the second copper sleeve 22 and welded to the second copper sleeve 22.

[0056] The upper section 11A of the first steel pipe expands outward. The inner diameter of the first copper sleeve 12 is equal to the outer diameter of the upper section 11A of the first steel pipe. The lower section 22B of the second copper sleeve is flush with the lower section 21B of the second steel pipe. The end face of the lower section 22B of the second copper sleeve abuts against the end face of the upper section 11A of the first steel pipe. The first extension section of the first copper sleeve 12 does not completely cover the second copper sleeve 22, so that the upper section 22A of the second copper sleeve extends out of the upper section 12A of the first copper sleeve by a predetermined length. The connection method in this embodiment increases the strength of the joint of the pipeline connection structure, reduces the risk of pipeline fracture and leakage, and improves the reliability of the pipeline connection structure.

[0057] Embodiment 2:

[0058] As Figure 12 shown, the difference between this embodiment and Embodiment 1 is that there is a certain distance between the end face of the lower section 22B of the second copper sleeve and the end face of the upper section 11A of the first steel pipe. The rest is the same as that in Embodiment 1 and will not be elaborated here.

[0059] In this embodiment, there is a certain distance between the end face of the lower section 22B of the second copper sleeve and the end face of the upper section 11A of the first steel pipe, which can be applied to the occasions where the axial length of the connection part is relatively large.

[0060] Embodiment 3:

[0061] As Figure 13 shown, the difference between this embodiment and Embodiment 1 is that the lower section 22B of the second copper sleeve extends beyond the lower section 21B of the second steel pipe to form a second extension section, and the end face of the second extension section abuts against the end face of the upper section 11A of the first steel pipe. The rest is the same as that in Embodiment 1 and will not be elaborated here.

[0062] In the third embodiment, a certain distance is provided between the first steel pipe 11 and the second steel pipe 21. The weld penetration of the solder is large and the sealing performance is good, which can avoid the problem of dripping of excess solder.

[0063] Embodiment Four:

[0064] In this embodiment, as Figure 14 shown, the pipeline connection structure includes a first steel pipe 11, a first copper sleeve 12, a second steel pipe 21 and a second copper sleeve 22. The first steel pipe 11 has an upper section 11A of the first steel pipe and a lower section 11B of the first steel pipe. The second steel pipe 21 has a lower section 21B of the second steel pipe and an upper section 21A of the second steel pipe. The first copper sleeve 12 has an upper section 12A of the first copper sleeve and a lower section 12B of the first copper sleeve. The second copper sleeve 22 has a lower section 22B of the second copper sleeve and an upper section 22A of the second copper sleeve. The first copper sleeve 12 is sleeved outside the upper section 11A of the first steel pipe. In the figure, the upper section 12A of the first copper sleeve is located at the upper part, the lower section 12B of the first copper sleeve is located at the lower part, the upper section 11A of the first steel pipe is located at the upper part, the lower section 11B of the first steel pipe is located at the lower part, and the upper section 12A of the first copper sleeve extends beyond the upper section 11A of the first steel pipe to form a first extension section. The second copper sleeve 22 is sleeved on the lower section 21B of the second steel pipe. The first steel pipe 11 and the first copper sleeve 12 are welded into one body, the second steel pipe 21 and the second copper sleeve 22 are welded into one body, and the first extension section of the first copper sleeve 12 is sleeved outside the second copper sleeve 22 and welded to the second copper sleeve 22.

[0065] The upper section 11A of the first steel pipe and the lower section 11B of the first steel pipe have the same dimensions. The inner diameter of the lower section 12B of the first copper sleeve is equal to the outer diameter of the first steel pipe 11. The inner diameter of the upper section 12A of the first copper sleeve is smaller than the inner diameter of the lower section 12B of the first copper sleeve and is equal to the outer diameter of the second copper sleeve 22. The lower section 22B of the second copper sleeve and the upper section 22A of the second copper sleeve have the same dimensions. The lower section 21B of the second steel pipe and the upper section 21A of the second steel pipe have the same dimensions.

[0066] The end face of the upper section 11A of the first steel pipe is located at the dimension change position between the upper section 12A of the first copper sleeve and the lower section 12B of the first copper sleeve. A positioning protrusion 111 for stopping the lower section 22B of the second copper sleeve is provided on the inner wall of the first steel pipe 11. The lower section 22B of the second copper sleeve extends into the first steel pipe 11 and makes the end face of the lower section 22B of the second copper sleeve contact the positioning protrusion 111 on the inner wall of the first steel pipe 11. The first extension section of the first copper sleeve 12 does not completely cover the second copper sleeve 22, so that the upper section 22A of the second copper sleeve extends out of the upper section 12A of the first copper sleeve by a predetermined length. Embodiment Five:

[0067] In this embodiment, as Figure 15As shown, the pipeline connection structure includes a first pipe 31, a second pipe 41, and a third copper sleeve 42. The first pipe 31 is a copper pipe or a copper-plated pipe. The second pipe 41 is a steel pipe. The third copper sleeve 42 is sleeved outside the lower section 41B of the second pipe and welded to the second pipe 41. The upper section of the first pipe 31 is sleeved outside the third copper sleeve 42 and welded to the third copper sleeve 42. The lower section of the third copper sleeve 42 extends out from the lower section 41B of the second pipe. The upper section of the first pipe 31 is enlarged to form a transition section. A filter ring 5 is provided between the lower section 41B of the second pipe and the transition section of the first pipe 31.

[0068] In this embodiment, by providing the filter ring 5, it is possible to prevent solder from falling into the compressor.

[0069] In the description of the present invention, it should be understood that the terms "center", "longitudinal", "lateral", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. indicate the orientation or positional relationship based on the orientation or positional relationship shown in the drawings. They are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation. Therefore, it should not be construed as a limitation of the present invention.

[0070] In addition, the terms "first" and "second" are only used for descriptive purposes and cannot be construed as indicating or implying relative importance or implicitly specifying the quantity of the indicated technical features. Thus, the features defined with "first" and "second" may explicitly or implicitly include at least one of such features. In the description of the present invention, the meaning of "a plurality" is at least two, such as two, three, etc., unless otherwise specifically defined.

[0071] In the present invention, unless otherwise clearly defined and limited, the terms "mounted", "connected", "connected to", "fixed", etc. should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or integrated; it may be a mechanical connection, an electrical connection, or communicable with each other; it may be directly connected, or indirectly connected through an intermediate medium. It may be the internal communication of two elements or the interaction relationship between two elements, unless otherwise clearly limited. For those of ordinary skill in the art, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0072] In the present invention, unless otherwise clearly specified or limited, the first feature being "on" or "under" the second feature may mean that the first and second features are in direct contact, or the first and second features are indirectly in contact through an intermediate medium. Moreover, the first feature being "above", "over" and "on top of" the second feature may mean that the first feature is directly above or obliquely above the second feature, or merely indicates that the first feature has a higher level height than the second feature. The first feature being "under", "below" and "beneath" the second feature may mean that the first feature is directly below or obliquely below the second feature, or merely indicates that the first feature has a lower level height than the second feature.

[0073] In the present invention, the terms "one embodiment", "some embodiments", "example", "specific example", or "some examples", etc. mean that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present invention. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described may be combined in a suitable manner in any one or more embodiments or examples. In addition, without contradiction, those skilled in the art may combine and combine the different embodiments or examples described in this specification and the features of the different embodiments or examples.

[0074] Although the embodiments of the present invention have been shown and described above, it can be understood that the above embodiments are exemplary and should not be construed as limiting the present invention. Those of ordinary skill in the art can make changes, modifications, substitutions, and variations to the above embodiments within the scope of the present invention.

Claims

1. A pipeline connection structure, characterized in that, it includes a first steel pipe, a first copper sleeve, a second steel pipe and a second copper sleeve. The first steel pipe includes an upper section of the first steel pipe and a lower section of the first steel pipe. The second steel pipe includes an upper section of the second steel pipe and a lower section of the second steel pipe. The first copper sleeve includes an upper section of the first copper sleeve and a lower section of the first copper sleeve. The second copper sleeve includes an upper section of the second copper sleeve and a lower section of the second copper sleeve. The first copper sleeve is sleeved on the upper section of the first steel pipe and the upper section of the first copper sleeve extends beyond the upper section of the first steel pipe to form a first extension section. The second copper sleeve is sleeved on the lower section of the second steel pipe. The first steel pipe is welded to the first copper sleeve. The second steel pipe is welded to the second copper sleeve. The first extension section of the first copper sleeve is sleeved outside the second copper sleeve and welded to the second copper sleeve; the lower section of the second copper sleeve extends beyond the lower section of the second steel pipe to form a second extension section. The lower end face of the second extension section abuts or is spaced from the end face of the upper section of the first steel pipe. The end face of the lower section of the second steel pipe and the end face of the upper section of the first steel pipe have a space along the axial direction. The first extension section and the second extension section are sleeved and welded, and a welding overlap area is formed between them along the radial direction. The welding overlap area is located between the end face of the lower section of the second steel pipe and the end face of the upper section of the first steel pipe.

2. The pipeline connection structure according to claim 1, characterized in that, the upper section of the second copper sleeve extends out of the upper section of the first copper sleeve by a predetermined length.

3. The pipeline connection structure according to claim 2, characterized in that, the first steel pipe or the first copper sleeve is a through-diameter pipe or a stepped pipe.

4. The pipeline connection structure according to any one of claims 1-3, characterized in that, the lower section of the second copper sleeve extends into the first steel pipe.

5. The pipeline connection structure according to claim 4, characterized in that, a positioning protrusion for stopping the lower section of the second copper sleeve is provided on the inner wall of the first steel pipe.

6. The pipeline connection structure according to claim 1, characterized in that, the upper section of the first steel pipe is in a flared shape or a tapered shape.

7. A compressor assembly, characterized in that, it includes a compressor and the pipeline connection structure according to any one of claims 1-6.

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