CN111561626A - Silencing pipeline - Google Patents

Abstract

The invention relates to the technical field of noise elimination and vibration isolation of pipeline systems, and discloses a noise elimination pipeline which comprises an outer-layer corrugated pipe and an inner-layer guide cylinder, wherein the guide cylinder is a porous flexible pipe, a circular channel defined by the inner wall of the guide cylinder is a pipeline flow channel, and a noise elimination cavity is formed by the outer wall of the guide cylinder and the inner side surface of the corrugated pipe. According to the silencing pipeline provided by the invention, the guide cylinder is sleeved in the corrugated pipe to form a sleeve structure, the outer wall of the guide cylinder and the inner side surface of the corrugated pipe form a silencing cavity, a flowing working medium can enter the silencing cavity from porous pores on the hole wall of the guide cylinder, and a pipeline flow passage and fluid medium exchange of the silencing cavity are formed; the porous wall surface of the guide cylinder can generate a porous silencing effect on the flowing medium, and the silencing cavity can generate a volume impedance effect of the expansion chamber on the flowing medium; therefore, the pressure pulsation and flow noise of the fluid medium in the pipeline are absorbed and attenuated, the sound absorption and silencing effects are exerted, and the noise transmission through the fluid medium in the pipeline is weakened.

Description

a muffler pipe

technical field

The invention relates to the technical field of noise reduction and vibration isolation of pipeline systems, in particular to a noise reduction pipeline.

Background technique

The fluid conveying pipeline system transmits mass flow, momentum flow or energy flow through fluid flow, and is widely used in various industrial and civil fields. In order to realize the active drive of the fluid working medium, the piping system needs to be equipped with rotating equipment such as pumps and fans; and the inlet and outlet of the rotating equipment need to be installed with flexible nozzles. The vibration is elastically isolated to reduce the transmission of vibration generated by the operation of rotating machinery and equipment along the piping system; the second is to appropriately compensate for the structural displacement between the piping systems caused by thermal expansion, vibration, impact, etc.

Corrugated pipe is a thin-walled elastic pipeline connection with transverse corrugations. It has good vibration isolation effect, strong displacement compensation ability, and can withstand frequent cyclic loads. It is widely used in energy, chemical, environmental protection and other industrial fields. in the delivery piping system. However, the existing pipeline has a poor effect of suppressing the noise transmission of the fluid working medium in the pipeline, and cannot meet the requirements for noise reduction and noise reduction of the pipeline.

SUMMARY OF THE INVENTION

The embodiment of the present invention provides a noise reduction pipeline, which is used to solve the problem that the existing pipeline has a poor effect of suppressing the noise transmission of the fluid working medium in the pipeline and cannot meet the noise reduction and noise reduction requirements of the pipeline.

An embodiment of the present invention provides a noise reduction pipeline, which includes an outer corrugated tube and an inner flow guide tube, the flow guide tube is a porous flexible tube, and the circular channel enclosed by the inner wall of the flow guide tube is In the pipeline flow channel, the outer wall of the guide tube and the inner side surface of the bellows form a muffler cavity.

Wherein, the inner wall of the guide tube is a flat straight wall, and the outer diameter of the guide tube is smaller than the inner diameter of the bellows.

Wherein, the outer wall of the guide tube is a flat straight wall, or a ring groove wall surface that fluctuates periodically along the axial direction.

Wherein, the wave shape of the wall surface of the annular groove of the guide tube in the axial direction is a rectangular wave, a triangular wave or a sine wave.

Wherein, it also includes end flanges arranged at both ends of the diversion cylinder, the end face of the diversion cylinder is flush with the outer end surface of the end flange, and the end of the bellows and the end flange of the end flange are flush. Inner end face connection.

Wherein, it also includes a fixed pressure ring, the end of the guide cylinder is provided with an annular stepped groove for installing the fixed pressure ring, and the outer end surface of the fixed pressure ring is flush with the end surface of the guide cylinder, so The inner wall of the fixed pressure ring is flush with the inner wall of the guide cylinder, and the fastening screws passing through the fixed pressure ring and the guide cylinder in turn in the radial direction are threadedly connected to the end flange.

Wherein, the fastening screws are in-line or cross-shaped or hexagonal or plum-shaped countersunk head screws, the head end face of the fastening screws is flush with the inner wall of the fixing pressure ring, and a plurality of the The fastening screws are evenly distributed along the circumferential direction of the fixed pressure ring.

Wherein, the corrugated tube is an Ω-shaped metal thin-walled tube.

Wherein, the concave part of the outer side surface of the corrugated tube is nested with a reinforcing collar.

Wherein, the material of the guide tube is metal rubber.

In the muffler pipeline provided by the embodiment of the present invention, a diversion tube is sleeved in the bellows to form a casing structure, and the circular channel enclosed by the inner wall of the diversion tube forms a pipeline flow channel through which the fluid working medium flows. The bellows and the guide tube made of porous flexible materials can effectively isolate the mechanical vibration transmission of the excitation source of the dynamic equipment such as pumps and fans in the fluid conveying pipeline system, and the tube can be adjusted by axial expansion and radial bending. The transient displacement of the road system under the action of vibration and shock is compensated. At the same time, the outer wall of the diversion cylinder and the inner side of the bellows form a muffler cavity, and the flowing working medium can enter the muffler cavity from the porous pores of the hole wall of the diversion cylinder, and form the fluid medium exchange between the pipeline flow channel and the muffler cavity; diversion; The porous wall of the cylinder can produce a porous muffler effect on the flowing working medium, and the muffler cavity can produce an expansion chamber volume impedance effect on the flowing working medium. The noise is absorbed and attenuated, so as to play the role of sound absorption and noise reduction, and reduce the noise transmission through the fluid medium inside the pipeline. Therefore, the muffler pipeline provided by the embodiment of the present invention can simultaneously realize the composite functions of mechanical vibration isolation, displacement deformation compensation and in-pipe muffler, the device is compactly integrated, and the composition and configuration of the fluid conveying pipeline system is simplified.

Description of drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description These are some embodiments of the present invention. For those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of a muffler pipeline provided by an embodiment of the present invention;

FIG. 2 is a schematic structural diagram of a muffler pipeline with the outer wall of a rectangular annular groove provided by another embodiment of the present invention;

FIG. 3 is a schematic structural diagram of a muffler pipeline with the outer wall of a triangular annular groove provided by another embodiment of the present invention;

4 is a schematic structural diagram of a muffler pipeline provided by another embodiment of the present invention in which the guide tube is the outer wall of the sinusoidal wave ring groove;

5 is a side view of a muffler pipeline structure provided by an embodiment of the present invention;

In the figure: 1. Corrugated pipe; 2. Reinforcing collar; 3. End flange; 4. Fastening screw; 5. Guide tube; 6. Muffler chamber; 7. Fixed pressure ring;

Detailed ways

The specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings and embodiments. The following examples are intended to illustrate the present invention, but not to limit the scope of the present invention.

In the description of the present invention, it should be noted that the terms "center", "portrait", "horizontal", "top", "bottom", "front", "rear", "left", "right", " The orientations or positional relationships indicated by vertical, horizontal, top, bottom, inside, and outside are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying It is described, rather than indicated or implied, that the device or element referred to must have a particular orientation, be constructed and operate in a particular orientation, and therefore should not be construed as limiting the invention. Furthermore, the terms "first," "second," "third," etc. are used for descriptive purposes only and should not be construed to indicate or imply relative importance.

In the description of the present invention, it should be noted that the terms "installed", "connected" and "connected" should be understood in a broad sense, unless otherwise expressly specified and limited, for example, it may be a fixed connection or a detachable connection Connection, or integral connection; can be mechanical connection, can also be electrical connection; can be directly connected, can also be indirectly connected through an intermediate medium, can be internal communication between two elements. 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 conditions.

In addition, in the description of the present invention, unless otherwise specified, "plurality", "plurality" and "plurality of groups" mean two or more.

As shown in FIG. 1 , an embodiment of the present invention provides a noise reduction pipeline, which includes an outer corrugated tube 1 and an inner guide tube 5 , the guide tube 5 is a porous flexible tube, and the inner wall of the guide tube 5 The enclosed circular channel is the pipeline flow channel 8 , and the outer wall of the guide tube 5 and the inner side surface of the bellows 1 form a muffler cavity 6 .

In the muffler pipeline provided by the embodiment of the present invention, a guide tube 5 is sleeved in the bellows 1 to form a casing structure, and the circular channel enclosed by the inner wall of the guide tube 5 forms a pipeline flow through which the fluid working medium flows. Road 8. The bellows 1 and the guide tube 5 made of porous flexible materials can effectively isolate the mechanical vibration transmission of the excitation source of dynamic equipment such as pumps and fans in the fluid conveying pipeline system, and can expand and bend radially through the two. Compensate the transient displacement of the pipeline system under the action of vibration and shock. At the same time, the outer wall of the guide cylinder 5 and the inner side of the bellows 1 form a muffler cavity 6, and the flowing working medium can enter the muffler cavity 6 from the porous pores of the hole wall of the guide cylinder 5, and form the pipeline flow channel 8 and the muffler cavity 6. the fluid medium exchange; the porous wall of the guide tube 5 can produce a porous muffler effect on the flowing working medium, and the muffler cavity 6 can produce an expansion chamber volume impedance effect on the flowing working medium; the porous muffler effect and the expansion chamber volume impedance effect have a The pressure pulsation and flow noise of the fluid medium inside the pipeline are absorbed and attenuated, so as to play the role of sound absorption and noise reduction, and reduce the noise transmission through the fluid medium inside the pipeline.

The isolation effect of the existing bellows is mainly effective for the vibration transmission of the pipeline structure, and the absorption capacity for pressure pulsation and noise transmitted along the fluid working medium is relatively poor. In the existing pipeline installation and layout scheme for isolating system vibration and noise, bellows and mufflers are installed independently in the pipeline system, and the bellows and the muffler are used to suppress the flow of working medium on the pipeline system to produce alternating effects. stress and reduce radiated noise, but the bellows and the muffler are installed independently along the pipeline, which leads to a complex structure of the pipeline system, or increases the processing, installation or maintenance costs of the bellows, and occupies a large space, which is not conducive to the compact and integrated design of the system. .

The muffler pipeline provided by the embodiment of the present invention can simultaneously realize the composite functions of mechanical vibration isolation, displacement deformation compensation and in-pipe muffler, the device is compactly integrated, and the composition and configuration of the fluid conveying pipeline system is simplified.

In a specific embodiment, the corrugated pipe 1 is a wave-like Ω-shaped metal thin-walled pipe; the metal thin-walled corrugated pipe has a longer fatigue life and better stability. The concave part of the outer side surface of the corrugated tube 1 can be nested with a reinforcing collar 2 , and the reinforcing collar 2 can be made of metal material and has the function of supporting and strengthening the corrugated tube 1 . The guide cylinder 5 is a cylindrical part processed and shaped using a flexible porous material, and the material of the guide cylinder 5 can be metal rubber. Metal rubber is a kind of homogeneous elastic porous material. It uses a certain process method to arrange the metal wires of a certain quality, stretched, and spiral state in an orderly manner in a stamping (or rolling) die, and then using a certain process method. It is formed by cold stamping method, and has the elasticity of rubber and the pore characteristics of porous metal at the same time; its raw material is metal filament, and the metal filament material is chemically stable in the internal environment of the fluid conveying pipeline system, and has the inherent properties of the selected metal. It has the characteristics of rubber-like elasticity.

In a specific embodiment, the inner wall of the guide tube 5 is a flat straight wall, which reduces the additional resistance to the flow of the working medium; the circular channel enclosed by the inner wall of the guide tube 5 forms the pipeline flow channel 8 through which the fluid working medium flows, The inner diameter of the inner wall of the guide tube 5 is the same as the inner diameter of the connected pipeline system, so that the fluid working medium flows smoothly in the pipeline system. The outer diameter of the guide tube 5 is smaller than the inner diameter of the bellows 1; for the variable diameter guide tube 5, the outer diameter of the guide tube 5 here includes its maximum outer diameter, and the inner diameter of the bellows 1 includes its minimum inner diameter.

The volume space between the outer wall of the guide tube 5 and the inner side of the bellows 1 forms a muffler cavity 6, and the muffler cavity 6 will have an expansion chamber volume impedance effect on the flowing working medium. The expansion chamber muffler formed by the volume impedance effect of the expansion chamber is one of the main forms of the resistive muffler; the resistive muffler is different from the resistive muffler in that it does not use sound-absorbing materials, but uses various shapes of pipes, cavities and chambers. The proper combination provides impedance mismatch of the piping system, causing reflection or interference of sound waves, thereby reducing the sound energy radiated by the muffler. The performance of the resistant muffler is related to the shape of the pipeline structure. Generally, the selectivity is strong, and it is suitable for the control of narrow-band noise and low and medium frequency noise.

Making the maximum outer diameter of the guide tube 5 smaller than the minimum inner diameter of the bellows 1 can also avoid the radial contact between the guide tube 5 and the bellows 1, thereby reducing the wear caused by pipeline vibration and displacement compensation deformation, and improving the casing. Reliability and service life of the tube structure.

In a specific embodiment, the outer wall of the guide cylinder 5 is a flat straight wall, or it can also be a wall surface of an annular groove that periodically undulates in the axial direction. The so-called annular groove wall surface with periodic undulations along the axial direction means that the outer diameter of the guiding tube 5 is a variable diameter tube with periodic changes. , the outer wall structure of the annular groove is formed at the small outer diameter relative to the large outer diameter. The outer wall of the guide tube 5 and the inner side of the bellows 1 form a muffler cavity 6. In the radial section perpendicular to the axis direction, the radial distance between the outer wall of the guide tube 5 and the inner side of the bellows 1 is the muffler cavity. 6. The width of the annular channel; in order to ensure that the outer wall of the guide tube 5 does not contact the inner side of the bellows 1, the amplitude of the outer wall of the guide tube 5 should be smaller than the width of the annular channel of the muffler cavity 6.

Further, the undulating waveform of the wall surface of the annular groove of the guide tube 5 in the axial direction may be a periodic rectangular wave as shown in FIG. 2 , forming a rectangular annular groove; or may be a periodic triangular wave as shown in FIG. 3 . , forming a triangular ring groove; or as shown in Figure 4, it can be a periodic sine wave to form a sine wave ring groove. The outer wall of the guide tube 5 has periodic undulations to form a ring groove structure, which can make the inner channel of the muffler cavity 6 more tortuous, and increase the absorption cross section of the flow noise and pressure pulsation of the guide tube 5, so that the pipe can be further improved. Road sound absorption and noise reduction.

In a specific embodiment, the muffler pipeline also includes end flanges 3 arranged at both ends of the guide tube 5, the end face of the guide tube 5 is flush with the outer end face of the end flange 3, and the end of the bellows 1 is flush with the end face of the end flange 3. The inner end face of the flange 3 is connected. End flanges 3 are provided at both ends of the casing structure formed by the outer layer corrugated pipe 1 and the inner layer guide tube 5 , and the pipe system is connected to the pipeline system through the end flanges 3 . The guide tube 5 of the inner layer can extend to the outer end face of the end flange 3, so that the end face of the guide tube 5 is flush with the outer end face of the end flange 3, and the outer wall of the guide tube 5 at the end is in line with the end flange 3. fit the inner wall. The end of the bellows 1 is connected to the inner end face of the end flange 3, and the inner end face of the end flange 3 can be provided with a convex-concave structure that matches the shape of the bellows 1, so that the end of the bellows 1 is connected to the end flange 3. The inner end face of the bellows is connected more closely; the end of the bellows 1 can be connected to the inner end face of the end flange 3 by welding.

In the existing pipeline structure, in order to reduce the scouring of the fluid on the connecting bellows and guide the fluid to flow smoothly, sometimes the bellows is lined with a rigid guide pipe in a single-sided manner; but the existing rigid guide The tube does not have the ability to compensate for axial displacement and bending deformation, cannot share the axial tension/compression effect of the external bellows, and will hinder its deformation when the bellows is bent, limiting the radial displacement compensation ability of the bellows; Moreover, the rigid guide tube fixed on one side is a cantilever structure, which is prone to vibration of the guide structure under the action of a high turbulent flow field, and has low reliability under long-term use conditions. The damage of the guide tube includes various forms such as impact shedding, high-frequency vibration deformation and high temperature deformation, which affect the service life of the pipeline and the reliability of the system operation. The diversion pipe may fall off as a whole or partially, which seriously threatens other facilities in the pipeline; when the bellows mainly plays the role of vibration isolation, the diversion pipe at the other end in a free state will also vibrate at a high frequency, resulting in deformation and rupture of the bellows ; In addition, if the lining expansion joint is unstable and is too close to the guide tube ring plate or the lining is loose near the ring plate, the entire guide tube ring plate will be twisted and deformed.

In the muffler pipeline provided by the embodiment of the present invention, the casing structure formed by the outer corrugated pipe 1 and the inner guiding cylinder 5 adopts the flexible material to process the lining guiding structure, which can avoid the connection between it and the outer corrugated pipe 1 . Structural interference improves the displacement compensation ability of the connecting pipeline; at the same time, because the guide tube 5 itself is flexible and can be fixed at both ends, it can effectively reduce the probability of damage such as falling off and deformation, and prolong the service life of the connecting pipeline.

In a specific embodiment, the muffler pipeline further includes a fixed pressure ring 7 , and an annular stepped groove for installing the fixed pressure ring 7 is provided at the end of the guide cylinder 5 . The outer end face of the fixed pressure ring 7 is flush with the end face of the diversion cylinder 5, so that the outer end face of the fixed pressure ring 7, the end face of the diversion cylinder 5 and the outer end face of the end flange 3 are all flush, which is convenient for pipeline connection. The inner wall of the fixed pressure ring 7 is flush with the inner wall of the diversion cylinder 5, so as to prevent the unevenness in the pipeline flow channel 8 from generating additional resistance that affects the flow. The fastening screws 4 which pass through the fixed pressure ring 7 and the guide tube 5 in turn in the radial direction are connected with the end flange 3 by screw thread. The fixing pressure ring 7 can be a metal O-ring, with fixing holes arranged in the radial direction; the guide cylinder 5 is arranged with through holes along the radial direction corresponding to the fixing holes, and the inner wall of the flange is arranged with threaded holes along the radial direction corresponding to the fixing holes and the through holes. The fixing screw 4 passes through the fixing hole and the through hole in turn, and is screwed into the threaded hole, and the fixing pressure ring 7 is fixed in the annular step groove, so that the fixing pressure ring 7, the guide tube 5 and the end flange 3 are tightly connected. The materials of the fixing pressure ring 7 and the fastening screw 4 are chemically stable in the internal environment of the fluid delivery pipeline system.

Further, the fastening screw 4 is a countersunk head screw, so that the end face of the head of the fastening screw 4 is flush with the inner wall of the fixed pressure ring 7; the head structure of the fastening screw 4 includes but is not limited to inline, cross, Hexagonal or plum blossom. The plurality of fastening screws 4 are evenly distributed along the circumference of the fixed pressure ring 7 , for example, as shown in FIG.

It can be seen from the above embodiments that the muffler pipeline provided by the present invention can use the flexible bellows 1 and the porous flexible guide tube 5 to excite the machinery of the dynamic equipment such as pumps and fans in the fluid conveying pipeline system. The vibration transmission is effectively isolated, and the transient displacement of the pipeline system under the action of vibration and impact is compensated through the axial expansion and radial bending of the two; And the volume impedance effect of the expansion chamber of the muffler cavity 6 absorbs and attenuates the pressure pulsation and flow noise of the fluid medium inside the pipeline, so as to play the role of sound absorption and noise reduction, and reduce the noise transmission through the fluid medium inside the pipeline. Through the functions of the above aspects, the muffler pipeline provided by the present invention has the composite functions of mechanical vibration isolation, deformation compensation and in-pipe muffling, and simplifies the composition and configuration of the fluid conveying pipeline system. In addition, because the guide tube 5 itself is flexible and can be fixed at both ends, it can effectively reduce the probability of damage such as falling off and deformation of the guide tube 5, enhance the reliability of the pipeline, reduce the installation and maintenance cost, and prolong the service life of the pipeline.

The above descriptions are only preferred embodiments of the present invention, and are not intended to limit the present invention. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the scope of the present invention. within the scope of protection.

Claims (10)

1. A silencing pipeline is characterized by comprising an outer-layer corrugated pipe and an inner-layer guide cylinder, wherein the guide cylinder is a porous flexible pipe, a circular channel defined by the inner wall of the guide cylinder is a pipeline flow channel, and a silencing cavity is formed by the outer wall of the guide cylinder and the inner side surface of the corrugated pipe.

2. The muffling pipeline of claim 1, wherein the inner wall of the guide cylinder is a flat straight wall, and the outer diameter of the guide cylinder is smaller than the inner diameter of the corrugated pipe.

3. The muffling pipeline of claim 2, wherein the outer wall of the guide cylinder is a flat straight wall or an annular groove wall surface which is periodically fluctuated along the axial direction.

4. The muffling pipeline according to claim 3, wherein the wall surface of the annular groove of the guide cylinder has a waveform in the axial direction that is a rectangular wave, a triangular wave, or a sinusoidal wave.

5. The muffling pipeline of any one of claims 1 to 4, further comprising end flanges disposed at both ends of the draft tube, wherein an end surface of the draft tube is flush with an outer end surface of the end flange, and an end portion of the corrugated tube is connected to an inner end surface of the end flange.

6. The muffling pipeline according to claim 5, further comprising a fixed pressing ring, wherein an annular step groove for installing the fixed pressing ring is formed in the end portion of the guide cylinder, the outer end face of the fixed pressing ring is flush with the end face of the guide cylinder, the inner wall of the fixed pressing ring is flush with the inner wall of the guide cylinder, and fastening screws which sequentially penetrate through the fixed pressing ring and the guide cylinder in the radial direction are in threaded connection with the end flange.

7. The muffling pipeline of claim 6, wherein the fastening screws are straight-line type or cross type or hexagon socket type or quincunx type countersunk screws, the end surfaces of the heads of the fastening screws are flush with the inner wall of the fixed compression ring, and the fastening screws are uniformly distributed along the circumferential direction of the fixed compression ring.

8. The muffling pipeline of any one of claims 1-4, 6, and 7, wherein the corrugated pipe is an omega-shaped thin-walled metal pipe.

9. The muffling pipeline of claim 8, wherein the outer side concave portion of the corrugated tube is nested with a reinforcing collar.

10. The muffling pipeline of claim 8, wherein the guide cylinder is made of metal rubber.

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