Processing technology of noise reduction Y-shaped tee joint

Abstract

This invention discloses a processing technology for noise-reducing Y-type tees, belonging to the field of Y-type tee processing technology, including the following steps: S1, composite tube blank preparation step: a three-layer composite tube blank is formed by co-extrusion process. The three-layer composite tube blank consists of a micro-perforated plate layer, a cavity layer, and a structural layer from the inside to the outside. The micro-perforated plate layer has multiple through-holes. The effect is that the co-extrusion process forms a three-layer composite tube blank consisting of a micro-perforated plate layer, a cavity layer, and a structural layer from the inside to the outside, and after integrated molding, the cavity layer forms a closed sound-absorbing cavity, thus constructing a "micro-perforated plate-resonant sound-absorbing cavity" composite noise reduction structure. This structure utilizes the Helmholtz resonance principle. When the low-to-medium frequency noise generated by the fluid flowing through the Y-type tee enters the micropores, the air generates viscous friction and sound energy consumption within the micropores, while resonance consumes sound energy within the cavity, achieving efficient absorption of fluid dynamic noise.

Description

Technical Field

[0001] This invention belongs to the field of Y-type tee processing technology, and in particular, a processing technology for noise-reducing Y-type tees. Background Technology

[0002] Y-type tees, as core connectors for diverting and merging fluids in pipeline systems, are widely used in water supply and drainage, HVAC, and industrial fluid transport. During pipeline operation, when fluid flows through the diverting / merging areas of the Y-type tee, abrupt changes in the flow channel cross-section and fluid direction can easily induce turbulence, eddies, and pressure pulsations, resulting in significant hydrodynamic noise. This not only affects the operational comfort of the pipeline system, but long-term high-intensity noise can also exacerbate pipeline vibration and structural fatigue, reducing the service life of the pipeline system.

[0003] Existing Y-type tees mostly use single-layer homogeneous plastic injection molding or metal pipe molding processes, with a solid wall structure. They only serve the functions of fluid conduction and structural load-bearing, and do not have active noise reduction capabilities. Some noise-reducing pipe fittings achieve passive noise reduction by wrapping sound-absorbing cotton on the outside and pasting sound-absorbing materials on the inside, but there are problems such as poor fit, easy detachment, occupation of flow channel space, and increased flow resistance. Moreover, they cannot be integrally molded with pipe fittings. After long-term use, the sound-absorbing layer ages and falls off, which will lead to noise reduction failure and high maintenance costs.

[0004] The purpose of this invention is to provide a processing technology for noise-reducing Y-type tees to solve the problems mentioned in the background art. Summary of the Invention

[0005] The purpose of this invention is to provide a processing technology for noise-reducing Y-type tees to solve the problems mentioned in the background art.

[0006] To achieve the above objectives, the present invention provides the following technical solution: a processing technology for a noise-reducing Y-type tee, comprising the following steps: S1. Composite tube blank preparation steps: A three-layer composite tube blank is formed by co-extrusion process. The three-layer composite tube blank consists of a micro-perforated plate layer, a cavity layer and a structural layer from the inside to the outside. The micro-perforated plate layer has multiple through-holes distributed on it. The cavity layer has a continuous void structure and is used to form a closed sound-absorbing cavity after final molding. S2. Cavity partitioning step: In the cavity layer, partition ribs are set along the circumferential and axial directions by hot melt welding or ultrasonic welding process to divide the cavity layer into multiple independent sub-cavities. S3, Integrated molding step: After heating the three-layer composite tube blank that has undergone the cavity separation step, place it in a Y-shaped tee mold. Through the blow molding process, the three-layer composite tube blank is integrally molded into the main structure of the Y-shaped tee in the mold, while keeping the multiple sub-cavities in the cavity layer sealed. S4. Post-processing steps: Cool and shape the Y-shaped tee body structure after molding, and trim the ends.

[0007] Furthermore, in the composite tube blank preparation step, the thickness of the micro-perforated plate layer is 0.3-0.8 mm, the pore diameter of the micropores is 0.2-0.5 mm, and the perforation rate of the micro-perforated plate layer is 1%-5%.

[0008] Furthermore, in the composite tube blank preparation step, the thickness of the cavity layer is 2-8 mm, and in the cavity partitioning step, the partition ribs arranged along the circumferential and axial directions divide the cavity layer into multiple independent sub-cavities. The depth dimension of each sub-cavity is 2-8 mm, and the depth dimensions of at least two sub-cavities are different from each other.

[0009] Furthermore, in the cavity partitioning step, the partitioning ribs arranged along the circumferential and axial directions include: multiple annular partitioning ribs arranged at equal intervals along the circumferential direction, each annular partitioning rib being arranged at intervals along the axial direction of the Y-shaped tee main structure, dividing the cavity layer into multiple axial sub-cavities along the axial direction; and multiple strip partitioning ribs arranged along the axial direction, each strip partitioning rib being arranged at intervals along the circumferential direction of the Y-shaped tee main structure, dividing the cavity layer into multiple circumferential sub-cavities along the circumferential direction. In the multiple sub-cavities, the depth dimensions of adjacent sub-cavities along the axial and circumferential directions of the Y-shaped tee main structure exhibit gradient changes or alternating changes.

[0010] Furthermore, in the cavity partitioning step, the partition ribs are set using a hot-melt welding process. When using the hot-melt welding process, the welding temperature is 180-260℃, the welding pressure is 0.2-0.6MPa, and the welding time is 3-10 seconds.

[0011] Furthermore, in the composite tube blank preparation step, the process parameters for forming the three-layer composite tube blank using a co-extrusion process are as follows: the extrusion temperature of the micro-perforated plate layer is 180-220℃, and the extrusion speed is 5-15 rpm; the extrusion temperature of the cavity layer is 150-180℃, and the extrusion speed is 3-10 rpm; the extrusion temperature of the structural layer is 200-240℃, and the extrusion speed is 10-20 rpm; and the extrusion speed ratio of the micro-perforated plate layer, the cavity layer, and the structural layer is 1:0.3-0.6:1.5-2.5, so that the thickness ratio of each layer in the formed three-layer composite tube blank reaches the preset ratio.

[0012] Furthermore, in the integrated molding step, the three-layer composite pipe blank is integrally molded into a Y-shaped tee main structure using a blow molding process: when using the blow molding process, the mold temperature is 40-80℃, the blowing pressure is 0.4-0.8MPa, the holding time is 15-30 seconds, and the cooling time is 40-80 seconds. The material of the composite pipe blank is selected from at least one of polypropylene, polyethylene, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer or blends thereof.

[0013] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention uses a co-extrusion process to form a three-layer composite tube blank consisting of a micro-perforated plate layer, a cavity layer, and a structural layer from the inside out. After integrated molding, the cavity layer forms a closed sound-absorbing cavity, thus constructing a "micro-perforated plate-resonant sound-absorbing cavity" composite noise reduction structure. This structure utilizes the Helmholtz resonance principle. When the low-to-medium frequency noise generated by the fluid flowing through the Y-shaped tee enters the micropores, the air generates viscous friction and sound energy consumption within the micropores. Simultaneously, resonance is generated within the cavity to consume sound energy, achieving efficient absorption of fluid dynamic noise. 2. By setting partition ribs along the circumferential and axial directions within the cavity layer, the cavity layer is divided into multiple independent sub-cavities, and at least two sub-cavities have different depth dimensions. Furthermore, the depth dimensions of adjacent sub-cavities change in a gradient or alternately. This design allows sub-cavities of different depths to correspond to different resonant frequencies. After multiple sub-cavities with different resonant frequencies are connected in parallel or in series, multiple sound absorption peaks can be formed, covering a wider noise frequency band and achieving a broadband noise reduction effect. Attached Figure Description

[0014] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0015] Figure 1 This is a schematic diagram of the structure of the present invention; Figure 2 This is a schematic diagram of the internal structure of the present invention; Figure 3 This is a schematic diagram of the process flow of the present invention.

[0016] Explanation of reference numerals in the attached figures: In the picture: 1. Y-type tee main structure; 2. Main pipe; 3. First branch pipe; 4. Second branch pipe; 5. Micro-perforated plate layer; 6. Cavity layer; 7. Structural layer; 8. Micropores; 9. Annular partition rib; 10. Strip partition rib; 11. Axial sub-cavity; 12. Circumferential sub-cavity. Detailed Implementation

[0017] In the following description, numerous specific details are set forth in order to provide a more thorough understanding of the invention. However, it will be apparent to those skilled in the art that the invention can be practiced without one or more of these details. In other instances, certain technical features well-known in the art have not been described in order to avoid obscuring the invention.

[0018] Unless otherwise defined, the directions mentioned herein, such as up, down, left, right, front, back, inside, and outside, are based on the directions shown in the figures of this invention, and are explained here together.

[0019] The connection method can be any existing method, such as bonding, welding, or bolting, depending on the actual needs. Example 1

[0020] This embodiment provides a processing technology for a noise-reducing Y-type tee, including the following steps: S1. Composite tube blank preparation steps This step forms a three-layer composite tube blank through a co-extrusion process. Specifically, three single-screw extruders are used to extrude micro-perforated plate material, cavity layer material and structural layer material respectively. The three-layer materials are then extruded together through a co-extrusion die to form a three-layer composite tube blank consisting of a micro-perforated plate layer, a cavity layer and a structural layer from the inside out. In this embodiment, the composite tube blank is made of polypropylene (PP), specifically Yanshan Petrochemical K8303. The process parameters are controlled as follows: Micro-perforated sheet: extrusion temperature 200℃, extrusion speed 10rpm; Cavity layer: Extrusion temperature is 165℃, and extrusion speed is 5rpm; Structural layer: Extrusion temperature is 220℃, and extrusion speed is 18rpm; The three-layer extrusion speed ratio is 1:0.5:1.8; After being formed by the above process, the thickness of the micro-perforated plate layer is 0.5 mm. Multiple through-holes are formed on the micro-perforated plate layer by the mold. The pore diameter is 0.3 mm and the perforation rate is 3%. The thickness of the cavity layer is 5 mm. It is a continuous void structure and is used to form a closed or semi-closed sound-absorbing cavity after final molding. The thickness of the structural layer is 2.5 mm. It serves as a load-bearing layer to provide structural strength.

[0021] S2, Cavity Separation Steps Within the cavity layer, partition ribs are set along the circumferential and axial directions using a hot-melt welding process to divide the cavity layer into multiple independent sub-cavities; Specifically, a hot melt welding machine is used to set multiple annular partition ribs at equal intervals along the circumference in the cavity layer. Each annular partition rib is arranged at intervals along the axial direction of the Y-shaped tee main structure, dividing the cavity layer into multiple axial sub-cavities along the axial direction. At the same time, multiple strip partition ribs are set along the axial direction. Each strip partition rib is arranged at intervals along the circumference of the Y-shaped tee main structure, dividing the cavity layer into multiple circumferential sub-cavities along the circumference. In this embodiment, there are 4 annular partition ribs, which are arranged at equal intervals along the axial direction to divide the cavity layer into 5 axial sub-cavities along the axial direction; there are 8 strip partition ribs, which are arranged at equal angles along the circumferential direction to divide the cavity layer into 8 circumferential sub-cavities along the circumferential direction. The two are combined to form a grid-like partition structure, which divides the cavity layer into 40 independent sub-cavities. The depth dimension of each sub-cavity is 2-8mm, and the depth dimension of adjacent sub-cavities changes in a gradient. Specifically, along the axial direction of the Y-type tee main structure, from the inlet end to the outlet end, the depths of each axial sub-cavity are 2mm, 4mm, 6mm, 8mm, and 6mm respectively, forming a symmetrical gradient distribution that first increases and then decreases. Along the circumferential direction, the depths of each circumferential sub-cavity change alternately, that is, sub-cavities with depths of 4mm and 6mm are arranged alternately. The hot-melt welding process parameters are controlled as follows: The welding temperature is 220℃; The welding pressure is 0.4 MPa; The welding time is 6 seconds; After the above welding process, the partition ribs form a firm sealed connection with the inner wall of the cavity layer, dividing the cavity layer into multiple independent sub-cavities of different depths. S3, Integrated Molding Steps After the three-layer composite pipe blank, which has undergone the cavity separation step, is heated to a softened state, it is placed in a Y-shaped tee mold. Through the blow molding process, the three-layer composite pipe blank is integrally formed into the main body structure of the Y-shaped tee in the mold, while the multiple sub-cavities in the cavity layer are kept in a sealed or semi-sealed state. The blow molding process parameters are controlled as follows: The mold temperature is 60℃; The blowing pressure is 0.6 MPa; The pressure holding time is 20 seconds; Cooldown time is 60 seconds; After blow molding, the three-layer composite pipe blank is fully bonded within the mold to form a Y-shaped tee main structure with a main pipe and two branch pipes. During the molding process, due to the precise positioning of the mold and the uniform effect of the blowing pressure, the partition ribs in the cavity layer remain intact, the sealing of each sub-cavity is good, and the microporous structure of the micro-perforated plate layer does not deform or become blocked. S4. Post-processing steps After the Y-shaped tee body structure is cooled and shaped, it is removed from the mold after the product has completely cooled to room temperature. The three ends of the tee are then trimmed with a trimming machine to remove burrs and flash, ensuring that the end face is flat and easy to connect to the pipe later. Example 2

[0022] This embodiment is basically the same as Embodiment 1, except that the composite tube blank is made of polyethylene (PE), specifically Yanshan Petrochemical 5000S, and some process parameters have been adjusted. S1. Composite tube blank preparation steps Micro-perforated sheet: Extrusion temperature is 190℃, extrusion speed is 8rpm; Cavity layer: Extrusion temperature is 160℃, and extrusion speed is 4rpm; Structural layer: Extrusion temperature is 210℃, and extrusion speed is 15rpm; The three-layer extrusion speed ratio is 1:0.5:1.9; After molding, the thickness of the micro-perforated plate layer is 0.4 mm, the micropore diameter is 0.25 mm, and the perforation rate is 2.5%; the thickness of the cavity layer is 4 mm; and the thickness of the structural layer is 2.2 mm. S2, Cavity Separation Steps In this embodiment, the depth of the sub-cavities changes in an alternating pattern. Along the axial direction of the Y-shaped tee main structure, the depths of the sub-cavities in each axial direction are 3mm, 5mm, 3mm, 5mm, and 3mm respectively, forming an alternating distribution of high and low. Along the circumferential direction, the depths of the sub-cavities in each circumferential direction also change alternately, that is, sub-cavities with depths of 3mm and 5mm are arranged alternately. Hot melt welding process parameters: welding temperature is 200℃, welding pressure is 0.3MPa, and welding time is 5 seconds; S3, Integrated Molding Steps The mold temperature is 50℃; The blowing pressure is 0.5 MPa; The pressure holding time is 18 seconds; Cooldown time is 50 seconds.

[0023] The remaining steps are the same as in Example 1, and will not be repeated here.

[0024] Comparative Example The comparative example uses a conventional Y-type tee processing technology, which is a single-layer injection molding process without micro-perforated plate layers, cavity layers, and partition rib structures. Other processing conditions of the comparative example (such as materials, mold temperature, molding pressure, etc.) are consistent with those of Example 1. Performance testing The noise reduction performance of the Y-type tee products prepared in Example 1, Example 2, and the comparative example was tested using the following methods: Install the Y-type tee in the piping system, with a flow rate of 10m³. 3 A sound level meter was placed 500 mm away from the outer wall of the tee to measure the noise level when the tee was running. At the same time, a pressure sensor was used to measure the pressure difference before and after the tee and calculate the flow resistance loss. The test results are as follows: Test results show that: 1. Compared with the comparative example, the noise level of Example 1 was reduced by 16.3 dB(A), and the noise level of Example 2 was reduced by 15.5 dB(A), showing a significant noise reduction effect; 2. The flow resistance loss in Examples 1 and 2 is not significantly increased compared with the comparative example, indicating that the noise reduction structure of the present invention does not introduce significant additional flow resistance while effectively reducing noise; 3. The noise reduction effect of Example 1 is slightly better than that of Example 2, indicating that the gradient-varying sub-cavity depth distribution has a better absorption effect on broadband noise.

[0025] In summary, significant noise reduction effects were achieved through the following technical means: 1. Composite structure of micro-perforated plate layer and cavity layer: The micropores on the micro-perforated plate layer and the sub-cavities in the cavity layer form multiple Helmholtz resonators, which can effectively absorb the low-to-mid frequency noise generated by fluid flow. The preferred parameters for the thickness of the micro-perforated plate layer are 0.3-0.8mm, the pore diameter is 0.2-0.5mm, and the perforation rate is 1%-5%, and the preferred parameters for the thickness of the cavity layer are 2-8mm. This results in a high sound absorption coefficient for the sound absorption structure in a wide frequency range of 200-2000Hz. 2. Differentiated depth sub-cavity design: By setting partition ribs along the circumferential and axial directions, the cavity layer is divided into multiple sub-cavities with different depths, and the depths of adjacent sub-cavities change in a gradient or alternately. This design allows different sub-cavities to correspond to different resonant frequencies. After multiple sub-cavities are connected in parallel or in series, they can cover a wider noise frequency band and achieve a wideband noise reduction effect. 3. Integrated molding process: A three-layer composite tube blank is formed through co-extrusion, then the partition ribs are set by hot melt welding, and finally integrated molding is carried out by blow molding or injection molding. This process ensures the precise composite between the micro-perforated plate layer, cavity layer and structural layer, as well as the sealing reliability of the partition ribs, avoiding gaps and sealing problems caused by secondary assembly, and ensuring the stability and consistency of the noise reduction structure. 4. Optimized process parameters: By precisely controlling the temperature and speed ratio of the co-extrusion process, the temperature, pressure and time of the welding process, and the mold temperature, pressure and holding time of the blow molding or injection molding process, the integrity of the microporous structure, the morphological stability of the cavity layer and the sealing reliability of the partition ribs are ensured, so that the above noise reduction structure can be stably realized in industrial production.

[0026] It should be noted that, in this document, relational terms such as "one" and "two" are used merely to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, the phrase "comprising an element defined as..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0027] Although embodiments of the invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A processing technology for a noise-reducing Y-type tee, characterized in that: Includes the following steps: S1. Composite tube blank preparation steps: A three-layer composite tube blank is formed by co-extrusion process. The three-layer composite tube blank consists of a micro-perforated plate layer, a cavity layer and a structural layer from the inside to the outside. The micro-perforated plate layer has multiple through-holes distributed on it. The cavity layer has a continuous void structure and is used to form a closed sound-absorbing cavity after final molding. S2. Cavity partitioning step: In the cavity layer, partition ribs are set along the circumferential and axial directions by hot melt welding or ultrasonic welding process to divide the cavity layer into multiple independent sub-cavities. S3, Integrated molding step: After heating the three-layer composite tube blank that has undergone the cavity separation step, place it in a Y-shaped tee mold. Through the blow molding process, the three-layer composite tube blank is integrally molded into the main structure of the Y-shaped tee in the mold, while keeping the multiple sub-cavities in the cavity layer sealed. S4. Post-processing steps: Cool and shape the Y-shaped tee body structure after molding, and trim the ends.

2. The processing technology of a noise-reducing Y-type tee according to claim 1, characterized in that: In the composite tube blank preparation step, the thickness of the micro-perforated plate layer is 0.3-0.8 mm, the pore diameter of the micropores is 0.2-0.5 mm, and the perforation rate of the micro-perforated plate layer is 1%-5%.

3. The processing technology of a noise-reducing Y-type tee according to claim 2, characterized in that: In the composite tube blank preparation step, the thickness of the cavity layer is 2-8 mm; In the cavity partitioning step, partition ribs arranged along the circumferential and axial directions divide the cavity layer into multiple independent sub-cavities. The depth dimension of each sub-cavity is 2-8 mm, and the depth dimensions of at least two sub-cavities are different from each other.

4. The processing technology of a noise-reducing Y-type tee according to claim 3, characterized in that: In the cavity partitioning step, the partition ribs arranged along the circumferential and axial directions include: Multiple annular partition ribs are evenly spaced along the circumference, and each annular partition rib is arranged at intervals along the axial direction of the Y-shaped tee main structure, dividing the cavity layer into multiple axial sub-cavities along the axial direction. Multiple strip-shaped dividing ribs are arranged axially, and each strip-shaped dividing rib is arranged at intervals along the circumference of the Y-shaped tee main structure, dividing the cavity layer into multiple circumferential sub-cavities. In the multiple sub-cavities, along the axial and circumferential directions of the Y-shaped tee main structure, the depth dimensions of adjacent sub-cavities exhibit gradient or alternating changes.

5. The processing technology of a noise-reducing Y-type tee according to claim 4, characterized in that: In the cavity partitioning step, the partition ribs are set using a hot-melt welding process; When using hot melt welding, the welding temperature is 180-260℃, the welding pressure is 0.2-0.6MPa, and the welding time is 3-10 seconds.

6. The processing technology of a noise-reducing Y-type tee according to claim 5, characterized in that: In the composite tube blank preparation step, the process parameters for forming the three-layer composite tube blank using co-extrusion are as follows: The extrusion temperature of the micro-perforated plate layer is 180-220℃, and the extrusion speed is 5-15 rpm; The extrusion temperature of the cavity layer is 150-180℃, and the extrusion speed is 3-10 rpm; The extrusion temperature of the structural layer is 200-240℃, and the extrusion speed is 10-20 rpm; Furthermore, the extrusion speed ratio of the micro-perforated plate layer, the cavity layer, and the structural layer is 1:0.3-0.6:1.5-2.5, so that the thickness ratio of each layer in the formed three-layer composite tube blank reaches the preset ratio.

7. The processing technology of a noise-reducing Y-type tee according to claim 6, characterized in that: In the integrated molding step, the three-layer composite tube blank is integrally molded into a Y-shaped tee main structure using a blow molding process: when using the blow molding process, the mold temperature is 40-80℃, the blowing pressure is 0.4-0.8MPa, the holding time is 15-30 seconds, and the cooling time is 40-80 seconds. The material of the composite tube blank is selected from at least one of polypropylene, polyethylene, polyvinyl chloride, acrylonitrile-butadiene-styrene copolymer or blends thereof.

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