Multi-section flaring small-diameter capillary tube, forming device and machining process

Abstract

According to the multi-section flaring small-diameter capillary tube, the forming device and the machining technology, the structure that a traditional multi-section flaring welding procedure is troublesome and low in quality is avoided, the multi-section flaring small-diameter capillary tube is efficiently connected with pipelines with different pipe diameters of a refrigerating system through a multi-section flaring structure, connecting parts and procedures are reduced, the cost is reduced, and the production efficiency is improved. The sealing performance and reliability of connection are improved, and the risk of refrigerant leakage is reduced. The flow state of internal fluid is changed through the arrangement of the turbulent flow grooves, the heat exchange efficiency of refrigerants and the pipe wall is enhanced, and therefore the refrigeration efficiency of the air conditioner refrigeration system is improved. According to the special capillary tube forming device, through cooperative work of the outer forming mold, the stamping mold core assembly, the turbulent flow hole side forming pressing block and the synchronous control push rod assembly, the chambering and turbulent flow groove machining process of the capillary tube can be accurately controlled, and the consistency of the machining precision and the product quality is guaranteed.

Description

Technical Field

[0001] The present invention relates to the technical field of refrigeration equipment pipelines, and particularly to a multi-section flared thin-diameter capillary tube, a forming device and a processing technology. Background Art

[0002] In an air-conditioning refrigeration system, as a key throttling component, the performance of the capillary tube directly affects the refrigeration efficiency and stability of the system, and it is difficult to meet the precise control requirements under complex working conditions; The prior art attempts to improve the connection performance by segmentally welding copper tubes with different diameters, but the welding process not only increases the production processes and costs, but also easily generates welding defects such as pores and cracks, resulting in refrigerant leakage and affecting the normal operation of the refrigeration system. At the same time, the fluid flow state inside the traditional capillary tube is single, and the heat exchange performance of the refrigerant cannot be fully exerted, reducing the energy efficiency of the refrigeration system.

[0003] Therefore, there is an urgent need to design a new capillary tube structure, its forming device and processing technology to solve the above technical problems and improve the overall performance of the air-conditioning refrigeration system.

[0004] Therefore, the existing refrigeration equipment pipeline technology field needs to be further improved. Summary of the Invention

[0005] The purpose of the present invention is to provide a multi-section flared thin-diameter capillary tube, a forming device and a processing technology. By optimizing the capillary tube structure, the connection performance and sealing reliability with the refrigeration system pipeline are improved; by designing a special forming device and processing technology, high-precision and high-efficiency production of the capillary tube is realized, thereby improving the refrigeration efficiency and stability of the air-conditioning refrigeration system and reducing the production cost. To achieve the above purpose, the present invention adopts the following solutions: A multi-section flared thin-diameter capillary tube includes a capillary tube, and multiple sections of expanded holes are integrally stamped inside the capillary tube, and a flow disturbance groove for changing the internal fluid flow state is arranged in each section of the expanded hole.

[0006] Further, multiple sections of the expanded holes are evenly distributed along the axial direction of the capillary tube, and the diameters gradually become smaller; the number of the expanded holes is three sections. Further, the capillary tube is made of copper material.

[0007] Further, a transition chamfer is arranged between two adjacent expanded holes.

[0008] A capillary forming device further includes an outer forming die and a stamping core component that can move within the outer forming die. In the stamping core component, a plurality of spoiler hole side forming blocks are provided, and a synchronous control push rod component for controlling the synchronous movement of the plurality of spoiler hole side forming blocks is movably arranged within the stamping core component.

[0009] Further, the outer forming die includes a die body, and an outer cavity is arranged within the die body.

[0010] Further, the stamping core component includes a stamping core that can move up and down within the outer cavity. The stamping core is provided with an expanding hole core having three sections with gradually decreasing diameters from top to bottom.

[0011] Further, the spoiler hole side forming block includes a plurality of press block guide holes arranged on the side wall of the expanding hole core, and side press blocks are movably arranged within the press block guide holes.

[0012] Further, the synchronous control push rod component includes a vertical hole arranged in the middle of the stamping core component. A bushing is arranged at the upper end of the vertical hole, and a secondary push shaft is movably arranged up and down within the bushing. A plurality of first hinge seats are arranged on the secondary push shaft, and a second hinge portion is arranged on the side press block. A connecting rod is hinged between the second hinge portion and a corresponding first hinge seat.

[0013] A capillary processing technology includes the following steps. S1. Select a phosphor-deoxidized copper capillary blank of a specific specification, and perform a cleaning treatment on it to remove surface impurities. S2. Place the capillary blank into the outer forming die of a specific capillary forming device. The inner diameter of the outer cavity of the die is adapted to the outer diameter of the blank. Use a stamping device to push the stamping core component downward, and use the expanding hole cores with three sections of gradually decreasing diameters on the component to stamp the blank in sequence to form three expanding holes with gradually decreasing diameters. The adjacent expanding holes are connected by a transition chamfer. S3. After the expanding hole is completed, drive the synchronous control push rod component without changing the position of the blank. Through the axial movement of the secondary push shaft, drive the side press block to radially extend through the connecting rod, stamp spoiler grooves on the inner walls of each section of the expanding hole. The spoiler grooves in each expanding hole are distributed in a circular array, and the adjacent two rows are staggered along the axial direction of the capillary. At the same time, accurately control the extension amount of the side press block to ensure that the depth tolerance of the spoiler groove is within a reasonable range.

[0014] S4. After stamping, first reset the side press block of the synchronous control push rod component, then take out the stamping core component, and then take out the capillary semi-finished product for straightening and surface polishing to make the inner wall of the expanding hole reach a certain roughness standard.

[0015] In summary, the beneficial effects of the present invention compared with the prior art are: The present invention solves the deficiencies existing in the prior art of the pipeline of refrigeration equipment. Through the structural arrangement of the present invention, the following advantages are achieved. The present invention avoids the structure with troublesome and low-quality multi-stage flaring and welding processes in the prior art. The multi-stage flared small-diameter capillary tube realizes efficient connection with pipelines of different diameters in the refrigeration system through a multi-stage reaming structure, reduces the connecting components and processes, improves the sealing performance and reliability of the connection, and reduces the risk of refrigerant leakage. The setting of the flow disturbance groove changes the internal fluid flow state, enhances the heat exchange efficiency between the refrigerant and the pipe wall, and thus improves the refrigeration efficiency of the air-conditioning refrigeration system. The special capillary tube forming device can precisely control the reaming and flow disturbance groove processing processes of the capillary tube through the coordinated operation of the outer forming die, the stamping core component, the flow disturbance hole side forming block, and the synchronous control push rod component, ensuring the processing accuracy and the consistency of product quality. At the same time, the device has a reasonable structure, is easy to operate, can realize automated production, improves production efficiency, and reduces production costs; the processing process steps are clear, and by precisely controlling the parameters and operations of each processing link, multi-stage flared small-diameter capillary tubes that meet the design requirements can be stably produced. From material preparation to the completion of finished product processing, the entire process is efficient and reliable, providing a strong guarantee for large-scale production. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Stereogram of the first capillary tube embodiment of the invention; Figure 2 Schematic diagram of the cooperation between the core and the capillary tube of the invention; Figure 3 Cross-sectional view of the cooperation between the core and the capillary tube of the invention; Figure 4 Cross-sectional view of the stamping and punching process of the invention; Figure 5 Schematic diagram of the die structure of the invention; Figure 6 Stereogram of the second capillary tube embodiment of the invention. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0017] The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only a part of the embodiments of the present invention, rather than all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without making creative efforts shall fall within the protection scope of the present invention.

[0018] Please refer to Figures 1-6 , the present invention provides a multi-stage flared small-diameter capillary tube, including a capillary tube 1, and multi-stage reaming holes 2 are integrally formed by stamping inside the capillary tube 1, and a flow disturbance groove 3 for changing the internal fluid flow state is arranged in each of the reaming holes 2.

[0019] In the present invention, the multiple sections of the flared holes 2 are evenly distributed along the axial direction of the capillary 1 and the diameter gradually decreases; the number of the flared holes 2 is three sections. The capillary 1 in the present invention is made of copper material.

[0020] A transition chamfer 4 is arranged between two adjacent flared holes 2 in the present invention.

[0021] Compared with the prior art, the present tooling achieves: Improved sealing performance: the flared port contact area increases by 40%, and the leakage rate < 0.1% / thousand hours (measured data); Process integration: multiple sections of flared ports are completed in a single processing, and the production efficiency is increased by 60%; Cost optimization: welding consumables are eliminated, and the unit cost is reduced by ¥1.2 / m.

[0022] The sizes of the three sections of the flared holes 2 are φ2.0 → φ2.8 → φ3.5mm; A capillary forming device further includes an outer forming die 5 and a stamping core assembly 6 that can move within the outer forming die 5. In the stamping core assembly 6, a plurality of spoiler hole side forming press blocks 7 are arranged, and a synchronous control push rod assembly 8 for controlling the synchronous movement of the plurality of spoiler hole side forming press blocks 7 is movably arranged within the stamping core assembly 6; According to the design requirements, a phosphor deoxidized copper material meeting the national standard is selected as the capillary blank, and its specifications meet the specific requirements for the outer diameter and wall thickness dimensions. The selected blank is subjected to a cleaning treatment, and ultrasonic cleaning or other methods can be used to remove impurities such as oil stains and dust on the surface, ensuring that the surface of the blank is clean and preparing for subsequent processing.

[0023] Install the outer forming die 5 on the workbench of the stamping equipment to ensure that the die is firmly installed and in the correct position. Assemble and debug the stamping core assembly 6, the spoiler hole side forming press blocks 7, and the synchronous control push rod assembly 8, and check the movement flexibility and mating accuracy of each component. Adjust parameters such as the pressure and stroke of the stamping equipment to meet the processing requirements.

[0024] Place the cleaned capillary blank into the outer cavity 502 of the outer forming die 5, start the stamping equipment, and drive the stamping core assembly 6 to move downward. The three sections of flared hole cores 602 on the stamping core 601 sequentially stamp the capillary blank to form three sections of flared holes 2 with gradually decreasing diameters within the capillary 1. During the stamping process, strictly control the stamping speed and pressure to ensure the dimensional accuracy and surface quality of the flared holes. At the same time, the adjacent flared holes are connected by a transition chamfer 4, and the size and shape of the transition chamfer 4 can be adjusted according to the design requirements to ensure a smooth transition at the connection part.

[0025] After the reaming process is completed, keep the position of the capillary blank in the mold unchanged and start the synchronous control push rod assembly 8. By controlling the axial movement of the secondary push shaft 803 within the bushing 802, through the transmission of the connecting rod 806, the side pressing block 702 is driven to radially extend within the pressing block guide hole 701, and turbulator grooves 3 are stamped on the inner walls of each section of the reamed hole 2. The turbulator grooves 3 within each reamed hole 2 are distributed in a circular array, and two adjacent rows of turbulator grooves 3 along the axial direction of the capillary 1 are staggered. Precisely control the extension amount and stamping force of the side pressing block 702 to ensure that the dimensions such as the depth and width of the turbulator grooves 3 meet the design requirements, and at the same time ensure the surface quality of the turbulator grooves 3.

[0026] After the stamping process is completed, first reset the side pressing block 702 of the synchronous control push rod assembly 8, and then withdraw the stamping core assembly 6 from the outer forming mold 5. Take out the processed capillary semi-finished product and straighten it. Mechanical straightening or hydraulic straightening and other methods can be used to ensure the straightness of the capillary. Then, perform surface polishing treatment on the capillary. Processes such as grinding and polishing can be used to make the inner wall of the reamed hole 2 reach the specified roughness standard, improving the surface quality and fluid flow performance of the capillary.

[0027] Conduct a comprehensive quality inspection on the processed multi-section flared and thin-diameter capillary, including dimensional accuracy inspections such as reamed hole diameter and turbulator groove dimensions, surface quality inspections such as roughness and whether there are cracks, and sealing performance inspections by methods such as pressure testing to detect the sealing performance after the capillary is connected to the pipeline. Analyze and process the unqualified products to ensure that the final products meet the design requirements and usage standards.

[0028] The stamping working pressure is 6 MPa, and the flow rate is 12 L / min; The outer forming mold 5 described in the present invention includes a mold body 501, and an outer cavity 502 is provided within the mold body 501.

[0029] The stamping core assembly 6 described in the present invention includes a stamping core 601 that can move up and down within the outer cavity 502, and the stamping core 601 is provided with reaming cores 602 with gradually decreasing diameters in three sections from top to bottom.

[0030] The turbulator hole side forming pressing block 7 described in the present invention includes a plurality of pressing block guide holes 701 provided on the side wall of the reaming core 602, and a side pressing block 702 is movably arranged within the pressing block guide holes 701.

[0031] The synchronous control push rod assembly 8 described in the present invention includes a vertical hole 801 provided in the middle of the stamping core assembly 6. An axle sleeve 802 is provided at the upper end of the vertical hole 801. A secondary push shaft 803 is movably arranged up and down within the axle sleeve 802. A plurality of first hinge seats 804 are provided on the secondary push shaft 803. A second hinge portion 805 is provided on the side pressing block 702. A connecting rod 806 is hinged between the second hinge portion 805 and a corresponding first hinge seat 804.

[0032] A capillary processing technology includes the following steps. S1. Select a phosphor-deoxidized copper capillary blank with a specific specification, clean it to remove surface impurities, and preheat the capillary to 80°C ± 5°C. S2. Place the capillary blank into the outer forming die 5 of a specific capillary forming device. The inner diameter of the outer die cavity 502 of this die is adapted to the outer diameter of the blank. Drive the stamping core assembly 6 to move downward by means of a stamping device, and use the three reaming cores 602 with gradually decreasing diameters on the assembly to stamp the blank in sequence to form three reamings 2 with gradually decreasing diameters. The adjacent reamings are connected by a transition chamfer 4. S3. After the reaming is completed, drive the synchronous control push rod assembly 8 without changing the position of the blank. Through the axial movement of the secondary push shaft 803, drive the side pressing block 702 to radially extend via the connecting rod 806, and stamp turbulence grooves 3 on the inner walls of each section of the reaming 2. The turbulence grooves 3 in each reaming 2 are distributed in a circular array, and are staggered in the axial direction of the capillary 1 for adjacent two rows. At the same time, precisely control the extension amount of the side pressing block 702 to ensure that the depth tolerance of the turbulence grooves 3 is within a reasonable range.

[0033] S4. After stamping, first reset the side pressing block 702 of the synchronous control push rod assembly 8, then take out the stamping core assembly 6, and then take out the capillary semi-finished product for straightening and surface polishing to make the inner wall of the reaming 2 reach a certain roughness standard.

[0034] The above shows and describes the basic principles, main features and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited by the above embodiments. What is described in the above embodiments and the specification only illustrates the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention will have various changes and improvements, and these changes and improvements all fall within the scope of the present invention claimed. The scope of the present invention claimed is defined by the appended claims and their equivalents.

Claims

1. A multi-stage flared small-diameter capillary tube, comprising a capillary tube (1), characterized in that: There are multiple sections of enlarged holes (2) integrally stamped and formed inside the capillary tube (1), and a flow disturbance groove (3) for changing the internal fluid flow state is arranged in each section of the enlarged hole (2).

2. The multi-stage flared capillary tube according to claim 1, wherein: The multiple sections of enlarged holes (2) are evenly distributed along the axial direction of the capillary tube (1), and the diameters gradually become smaller; the number of the enlarged holes (2) is three sections.

3. The multi-stage flared capillary tube according to claim 2, wherein: The capillary tube (1) is made of copper material.

4. A multi-stage flared capillary tube according to claim 3, characterized in that: A transition chamfer (4) is arranged between two adjacent enlarged holes (2).

5. A capillary forming device, comprising a multi-stage flared fine-diameter capillary according to any one of claims 1-4, characterized in that: It further includes an outer forming die (5) and a stamping core assembly (6) capable of moving inside the outer forming die (5). Multiple flow disturbance hole side forming blocks (7) are arranged inside the stamping core assembly (6), and a synchronous control push rod assembly (8) for controlling the synchronous movement of the multiple flow disturbance hole side forming blocks (7) is movably arranged inside the stamping core assembly (6).

6. A capillary forming device according to claim 5, characterized in that: The outer forming die (5) includes a die body (501), and an outer die cavity (502) is arranged inside the die body (501).

7. A capillary forming device according to claim 6, characterized in that: The stamping core assembly (6) includes a stamping core (601) capable of moving up and down inside the outer die cavity (502). The stamping core (601) is provided with enlarged hole cores (602) with gradually decreasing diameters in three sections from top to bottom.

8. A capillary forming device according to claim 7, characterized in that: The flow disturbance hole side forming block (7) includes a plurality of block guide holes (701) arranged on the side wall of the enlarged hole core (602), and a side forming block (702) is movably arranged inside the block guide holes (701).

9. The capillary forming device according to claim 8, characterized in that: The synchronous control push rod assembly (8) includes a vertical hole (801) arranged in the middle of the stamping core assembly (6). A bushing (802) is arranged at the upper end of the vertical hole (801). A secondary push shaft (803) is movably arranged up and down inside the bushing (802). A plurality of first hinge seats (804) are arranged on the secondary push shaft (803). A second hinge part (805) is arranged on the side forming block (702), and a connecting rod (806) is hinged between the second hinge part (805) and a corresponding first hinge seat (804).

10. A capillary processing technique, characterized in that: It includes the following steps S1. Select a phosphor deoxidized copper capillary tube blank with a specific specification, and perform a cleaning treatment on it to remove surface impurities. The capillary tube is preheated to 80°C ± 5°C; S2. Place the capillary tube blank into the outer forming die (5) of a specific capillary tube forming device. The inner diameter of the outer die cavity (502) of the die is adapted to the outer diameter of the blank. Push the stamping core assembly (6) downward by means of a stamping device, and use the three sections of enlarged hole cores (602) with gradually decreasing diameters on the assembly to stamp the blank in sequence to form three sections of enlarged holes (2) with gradually decreasing diameters. The adjacent enlarged holes are connected by a transition chamfer (4); S3. After the reaming is completed, drive the synchronous control push rod assembly (8) with the blank in the same position. Axially move the secondary push shaft (803), and drive the side pressing block (702) to radially extend through the connecting rod (806), and stamp out the turbulence grooves (3) on the inner walls of each section of the reamed hole (2). The turbulence grooves (3) in each reamed hole (2) are distributed in an annular array and are staggered in two adjacent rows along the axial direction of the capillary tube (1). At the same time, precisely control the extension amount of the side pressing block (702) to ensure that the depth tolerance of the turbulence grooves (3) is within a reasonable range; S4. After the stamping is completed, first reset the side pressing block (702) of the synchronous control push rod assembly (8), then take out the stamping core assembly (6), and then take out the capillary semi-finished product for straightening and surface polishing to make the inner wall of the reamed hole (2) reach a certain roughness standard.

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