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

Silencing pipeline

Technical Field

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

Background

The fluid conveying pipeline system transfers mass flow, momentum flow or energy flow through fluid flow and is widely applied to various industrial and civil fields. In order to realize active driving of fluid working media, a piping system needs to be provided with rotating equipment such as a pump, a fan and the like; the inlet and outlet of the rotating equipment need to be provided with flexible connecting pipes, and the purposes are mainly two: firstly, the vibration of rotating mechanical equipment such as an engine, a pump, a fan and the like is elastically isolated, and the transmission of the vibration generated by the running of the rotating mechanical equipment along a piping system is weakened; secondly, the structure displacement between the pipe systems caused by the functions of thermal expansion, vibration, impact and the like is properly compensated.

The corrugated pipe is a thin-wall elastic pipeline connecting piece with transverse corrugations, has good vibration isolation effect and strong displacement compensation capability, can bear frequent cyclic load action, and is widely applied to conveying pipeline systems in various industrial fields such as energy, chemical engineering, environmental protection and the like. However, the existing pipeline has poor noise transmission inhibiting effect on fluid working media in the pipe, and cannot meet the requirements of noise elimination and noise reduction of the pipeline.

Disclosure of Invention

The embodiment of the invention provides a silencing pipeline, which is used for solving the problems that the existing pipeline has poor noise transmission inhibiting effect on fluid working media in a pipe and cannot meet the requirements of silencing and denoising of the pipeline.

The embodiment of the invention provides a silencing 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 silencing cavity is formed by the outer wall of the guide cylinder and the inner side surface of the corrugated pipe.

The inner wall of the guide shell is a flat straight wall, and the outer diameter of the guide shell is smaller than the inner diameter of the corrugated pipe.

The outer wall of the guide cylinder is a flat straight wall or a ring groove wall surface which is periodically fluctuated along the axial direction.

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

The end flange is arranged at two ends of the guide shell, the end face of the guide shell is flush with the end face of the outer side of the end flange, and the end part of the corrugated pipe is connected with the end face of the inner side of the end flange.

Wherein, still include fixed clamping ring, the tip of draft tube is provided with and is used for the installation the annular step groove of fixed clamping ring, the outside end face of fixed clamping ring with the terminal surface parallel and level of draft tube, the inner wall of fixed clamping ring with the inner wall parallel and level of draft tube radially passes in proper order fixed clamping ring with the fastening screw of draft tube with end flange threaded connection.

The clamping ring is characterized in that the fastening screws are straight-line-shaped or cross-shaped or inner hexagonal or quincunx countersunk head screws, the head end faces of the fastening screws are flush with the inner wall of the fixed clamping ring, and the fastening screws are arranged along the circumferential uniform distribution of the fixed clamping ring.

Wherein, the corrugated pipe is an omega-shaped metal thin-wall pipe.

And a reinforcing lantern ring is nested in the concave part of the outer side surface of the corrugated pipe.

The guide cylinder is made of metal rubber.

According to the silencing pipeline provided by the embodiment of the invention, the guide shell is sleeved in the corrugated pipe to form a sleeve structure, and a circular channel defined by the inner wall of the guide shell forms a pipeline flow passage through which a fluid working medium flows. The corrugated pipe and the guide cylinder made of the porous flexible material can effectively isolate the mechanical vibration transmission of the excitation sources of dynamic equipment such as pumps, fans and the like in a fluid conveying pipeline system, and compensate the transient displacement of the pipeline system under the vibration and impact action through the axial extension and radial bending of the corrugated pipe and the guide cylinder. Meanwhile, the outer wall of the guide cylinder and the inner side surface of the corrugated pipe form an anechoic cavity, and the flowing working medium can enter the anechoic cavity from porous pores on the hole wall of the guide cylinder and form a pipeline flow passage for exchanging fluid media with the anechoic cavity; 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; the porous noise elimination effect and the expansion chamber volume impedance effect absorb and attenuate pressure pulsation and flow noise of fluid media in the pipeline, so that the sound absorption and elimination effects are exerted, and the noise transmission of the fluid media in the pipeline is weakened. Therefore, the silencing pipeline provided by the embodiment of the invention can simultaneously realize the composite functions of mechanical vibration isolation, displacement deformation compensation and in-pipe silencing, is compact in device integration, and simplifies the composition and configuration of a fluid conveying pipeline system.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and those skilled in the art can also obtain other drawings according to the drawings without creative efforts.

Fig. 1 is a schematic structural view of a muffling pipeline provided by an embodiment of the present invention;

fig. 2 is a schematic structural view of a sound-deadening pipeline with a rectangular annular groove as an outer wall of a guide cylinder according to another embodiment of the present invention;

fig. 3 is a schematic structural view of a silencing pipeline with a triangular ring groove as an outer wall of a guide cylinder according to another embodiment of the present invention;

fig. 4 is a schematic structural view of a silencing pipeline with a guide cylinder being an outer wall of a sine-wave-shaped ring groove according to another embodiment of the present invention;

FIG. 5 is a side view of a muffling piping structure provided by an embodiment of the present invention;

in the figure: 1. a bellows; 2. a reinforcing collar; 3. an end flange; 4. fastening screws; 5. a draft tube; 6. an anechoic chamber; 7. fixing the compression ring; 8. a pipeline flow passage.

Detailed Description

The following detailed description of embodiments of the present invention is provided in connection with the accompanying drawings and examples. The following examples are intended to illustrate the invention but are not intended to limit the scope of the invention.

In the description of the present invention, it should be noted that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate orientations or positional relationships based on those shown in the drawings, and are only for convenience of description and simplicity of description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed and operated in a specific orientation, and thus, should not be construed as limiting the present invention. Furthermore, the terms "first," "second," "third," and the like are used for descriptive purposes only and are not to be construed as indicating or implying relative importance.

In the description of the present invention, it should be noted that, unless otherwise explicitly specified or limited, the terms "mounted," "connected," and "connected" are to be construed broadly, e.g., as meaning either a fixed connection, a removable connection, or an integral connection; can be mechanically or electrically connected; they may be connected directly or indirectly through intervening media, or they may be interconnected between two elements. The specific meaning of the above terms in the present invention can be understood as appropriate by those of ordinary skill in the art.

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

As shown in fig. 1, an embodiment of the present invention provides a muffling pipeline, including an outer corrugated pipe 1 and an inner guide cylinder 5, where the guide cylinder 5 is a porous flexible pipe, a circular channel defined by an inner wall of the guide cylinder 5 is a pipeline flow channel 8, and an outer wall of the guide cylinder 5 and an inner side surface of the corrugated pipe 1 form a muffling cavity 6.

According to the silencing pipeline provided by the embodiment of the invention, the guide shell 5 is sleeved in the corrugated pipe 1 to form a sleeve structure, and a circular channel formed by the inner wall of the guide shell 5 forms a pipeline flow passage 8 through which a fluid working medium flows. The corrugated pipe 1 and the guide cylinder 5 made of porous flexible materials can effectively isolate the mechanical vibration transmission of pump, fan and other dynamic equipment excitation sources in a fluid conveying pipeline system, and compensate the transient displacement of the pipeline system under the action of vibration and impact through axial extension and radial bending of the corrugated pipe 1 and the guide cylinder. Meanwhile, the outer wall of the guide shell 5 and the inner side surface of the corrugated pipe 1 form a silencing cavity 6, a flowing working medium can enter the silencing cavity 6 from porous pores on the hole wall of the guide shell 5, and a pipeline flow passage 8 is formed for exchanging fluid media with the silencing cavity 6; the porous wall surface of the guide cylinder 5 can generate porous noise elimination effect on the flowing working medium, and the noise elimination cavity 6 can generate expansion chamber volume impedance effect on the flowing working medium; the porous noise elimination effect and the expansion chamber volume impedance effect absorb and attenuate pressure pulsation and flow noise of fluid media in the pipeline, so that the sound absorption and elimination effects are exerted, and the noise transmission of the fluid media in the pipeline is weakened.

The isolation function of the existing corrugated pipe mainly has an effect on vibration transmission of a pipeline structure, and the absorption capacity of pressure pulsation and noise transmitted along a fluid working medium is relatively poor. According to the existing pipeline installation and arrangement scheme for isolating system vibration and noise, a corrugated pipe and a silencer are independently installed in a pipeline system respectively, alternating stress is generated and radiation noise is reduced by inhibiting flowing working medium from acting on the pipeline system through the corrugated pipe and the silencer respectively, but the corrugated pipe and the silencer are independently installed along the pipeline respectively, so that the structure of the pipeline system is complex, or the machining, installation or maintenance cost of the corrugated pipe is increased, the occupied space is large, and the compact integrated design of the system is not facilitated.

The silencing pipeline provided by the embodiment of the invention can simultaneously realize the composite functions of mechanical vibration isolation, displacement deformation compensation and in-pipe silencing, is compact in device integration, and simplifies the composition configuration of a fluid conveying pipeline system.

In one embodiment, the corrugated pipe 1 is a wave-like omega-shaped metal thin-wall pipe; the metal thin-wall corrugated pipe has long fatigue life and good stability. The concave part of the outer side surface of the corrugated pipe 1 can be nested with a reinforcing lantern ring 2, and the reinforcing lantern ring 2 can be made of metal materials and has the functions of supporting and reinforcing the corrugated pipe 1. The guide shell 5 is a cylindrical part processed and shaped by adopting a flexible porous material, and the guide shell 5 can be made of metal rubber. The metal rubber is a homogeneous elastic porous substance, and is formed by orderly arranging a certain mass of stretched and spiral metal wires in a stamping (or rolling) die by a certain process method and then by a cold stamping method, and has the elasticity of rubber and the pore characteristics of porous metal; the raw material of the metal wire is metal wire which has stable chemical property in the internal environment of the fluid conveying pipeline system, and has the inherent characteristics of the selected metal and the elasticity like rubber.

In one specific embodiment, the inner wall of the guide shell 5 is a flat straight wall, so that the additional flow resistance of the working medium is reduced; the circular channel enclosed by the inner wall of the guide shell 5 forms a pipeline flow passage 8 through which the fluid working medium flows, and the inner diameter of the inner wall of the guide shell 5 is the same as that of a pipeline system connected with the guide shell, so that the fluid working medium can stably flow in the pipeline system. The outer diameter of the guide shell 5 is smaller than the inner diameter of the corrugated pipe 1; for a variable diameter guide shell 5, the outer diameter of the guide shell 5 includes its largest outer diameter, and the inner diameter of the bellows 1 includes its smallest inner diameter.

The volume space between the outer wall of the guide shell 5 and the inner side surface of the corrugated pipe 1 forms a silencing cavity 6, and the silencing cavity 6 generates a volume impedance effect of an expansion chamber on the flowing working medium. The expansion chamber silencer formed by the volume impedance effect of the expansion chamber is one of the main forms of the reactive silencer; reactive mufflers differ from resistive mufflers in that they do not use sound absorbing materials, but rather utilize various differently shaped pipes, chambers and chambers in appropriate combinations to provide impedance mismatches in the piping system to produce reflections or interference of sound waves and thereby reduce the sound energy radiated outwardly by the muffler. The performance of the reactive muffler is related to the shape of the pipeline structure, generally has stronger selectivity, and is suitable for controlling narrow-band noise and low and medium frequency noise.

The maximum outer diameter of the guide shell 5 is smaller than the minimum inner diameter of the corrugated pipe 1, and the guide shell 5 can be prevented from being in radial contact with the corrugated pipe 1, so that abrasion caused by pipeline vibration and displacement compensation deformation is reduced, the reliability of a sleeve structure is improved, and the service life of the sleeve structure is prolonged.

In a specific embodiment, the outer wall of the guide shell 5 is a flat straight wall, or may also be a circular groove wall surface which is periodically fluctuated along the axial direction. The annular groove wall surface which fluctuates periodically in the axial direction means that the guide shell 5 is a pipe with the outer diameter which changes periodically into a variable diameter, the outer wall of the guide shell 5 fluctuates periodically along the axial direction of the guide shell 5, and the outer wall surface structure of the annular groove is formed at the position with the small outer diameter relative to the position with the large outer diameter. The outer wall of the guide cylinder 5 and the inner side surface of the corrugated pipe 1 form an anechoic cavity 6, and the radial distance between the outer wall of the guide cylinder 5 and the inner side surface of the corrugated pipe 1 is the width of an annular channel of the anechoic cavity 6 on a radial section perpendicular to the axis direction; in order to ensure that the outer wall of the guide shell 5 is not in contact with the inner side surface of the corrugated pipe 1, the amplitude of the outer wall of the guide shell 5 should be smaller than the width of the annular channel of the muffling cavity 6.

Further, the undulation of the annular groove wall surface of the guide cylinder 5 along the axial direction may be a periodic rectangular wave as shown in fig. 2, forming a rectangular annular groove; or as shown in fig. 3, the ring groove is a periodic triangular wave to form a triangular ring groove; alternatively, as shown in fig. 4, the grooves may be periodic sine waves, forming sine wave-shaped grooves. The outer wall of the guide shell 5 has periodic fluctuation to form a ring groove structure, so that the internal channel of the silencing cavity 6 is more tortuous, the absorption cross section of flow noise and pressure pulsation of the guide shell 5 is increased, and the sound absorption and noise reduction effects of a pipeline can be further improved.

In a specific embodiment, the muffling pipeline further comprises end flanges 3 arranged at two ends of the guide cylinder 5, the end surfaces of the guide cylinder 5 are flush with the outer end surfaces of the end flanges 3, and the end portions of the corrugated pipe 1 are connected with the inner end surfaces of the end flanges 3. End flanges 3 are arranged at two ends of a sleeve structure formed by the outer-layer corrugated pipe 1 and the inner-layer guide cylinder 5, and the sleeve structure is connected into a pipeline system through the end flanges 3. The guide shell 5 of the inner layer can extend to the end face of the outer side of the end flange 3, so that the end face of the guide shell 5 is flush with the end face of the outer side of the end flange 3, and the outer wall of the end part of the guide shell 5 is attached to the inner wall of the end flange 3. The end part of the corrugated pipe 1 is connected with the end surface of the inner side of the end flange 3, and the end surface of the inner side of the end flange 3 can be provided with a convex-concave structure matched with the shape of the corrugated pipe 1, so that the end part of the corrugated pipe 1 is connected with the end surface of the inner side of the end flange 3 to be more attached; the end of the bellows 1 may be connected to the inner end face of the end flange 3 by welding.

In the existing pipeline structure, in order to weaken the washing of fluid to the connecting corrugated pipe and guide the fluid to flow stably, a rigid flow guide pipe is sometimes lined in the corrugated pipe in a mode of one-side fixed connection; however, the existing rigid flow guide pipe does not have the compensation capability of axial displacement and bending deformation, can not share the axial stretching/compressing action borne by the external corrugated pipe, and can hinder the deformation of the corrugated pipe when the corrugated pipe is bent, so that the radial displacement compensation capability of the corrugated pipe is limited; moreover, the rigid flow guide pipe fixedly connected on one side is of a cantilever structure, so that the flow guide structure is easy to vibrate under the action of a high-turbulence flow field, and the reliability is low under the long-term use condition. The damage of the flow guide pipe comprises various forms such as impact falling, high-frequency vibration deformation, high-temperature deformation and the like, and the service life of the pipeline and the operation reliability of the system are influenced. The honeycomb duct may fall off wholly or partially, so that other facilities in the pipeline are threatened seriously; when the corrugated pipe mainly plays a role of vibration isolation, the guide pipe with the other end in a free state also generates high-frequency vibration, so that the corrugated pipe deforms and breaks; in addition, if the liner expansion joint is unstably arranged and is too close to the annular plate of the draft tube or the liner is loose at the position close to the annular plate, the whole annular plate of the draft tube can be distorted and deformed.

According to the silencing pipeline provided by the embodiment of the invention, the sleeve structure formed by the outer corrugated pipe 1 and the inner guide cylinder 5 is a liner guide structure processed by adopting a flexible material, so that the structural interference between the liner guide structure and the outer corrugated pipe 1 can be avoided, and the displacement compensation capability of a connecting pipeline is improved; meanwhile, the guide cylinder 5 is flexible and can be fixed at two ends, so that the damage probability of falling, deformation and the like of the guide cylinder can be effectively reduced, and the service life of a connecting pipeline is prolonged.

In a specific embodiment, the silencing pipeline further comprises a fixed pressing ring 7, and an annular step groove for installing the fixed pressing ring 7 is formed in the end portion of the guide shell 5. The end face of the outer side of the fixed compression ring 7 is flush with the end face of the guide shell 5, so that the end face of the outer side of the fixed compression ring 7, the end face of the guide shell 5 and the end face of the end flange 3 are flush, and pipeline connection is facilitated. The inner wall of the fixed compression ring 7 is flush with the inner wall of the guide cylinder 5, so that the phenomenon that the pipeline flow channel 8 is uneven to generate additional resistance influencing flow is prevented. And the fastening screws 4 sequentially penetrate through the fixed compression ring 7 and the guide cylinder 5 along the radial direction and are in threaded connection with the end flange 3. The fixed compression ring 7 can be a metal O-shaped ring, and a fixed hole is arranged along the radial direction; the guide cylinder 5 is provided with a through hole corresponding to the fixing hole along the radial direction, the inner wall of the flange is provided with a threaded hole corresponding to the fixing hole and the through hole along the radial direction, the fastening screw 4 sequentially penetrates through the fixing hole and the through hole, the fastening screw is screwed with the threaded hole, the fixed compression ring 7 is fixed in the annular step groove, and the fixed compression ring 7, the guide cylinder 5 and the end flange 3 are tightly connected. The materials of the fixed compression ring 7 and the fastening screw 4 are stable in chemical property in the internal environment of the fluid conveying pipeline system.

Furthermore, the fastening screw 4 is a countersunk screw, so that the end face of the head of the fastening screw 4 is flush with the inner wall of the fixed compression ring 7; the head structure of the fastening screw 4 includes, but is not limited to, a straight type, a cross type, a hexagon socket type, or a quincunx type. The plurality of fastening screws 4 are evenly distributed along the circumferential direction of the fixed compression ring 7, and for example, as shown in fig. 5, six fastening screws 4 are evenly distributed along the circumferential direction of the fixed compression ring 7 at a circumferential angle of sixty degrees.

According to the embodiment, the noise elimination pipeline provided by the invention can effectively isolate the mechanical vibration transmission of the excitation sources of dynamic equipment such as a pump, a fan and the like in a fluid conveying pipeline system through the flexible corrugated pipe 1 and the porous flexible guide cylinder 5, and compensate the transient displacement of the pipeline system under the vibration and impact actions through the axial extension and radial bending of the flexible corrugated pipe 1 and the porous flexible guide cylinder; moreover, the pressure pulsation and flow noise of the fluid medium inside the pipeline are absorbed and attenuated by the porous noise elimination effect of the guide cylinder 5 made of the porous flexible material and the expansion chamber volume impedance effect of the noise elimination cavity 6, so that the sound absorption and elimination effects are exerted, and the noise transmission through the fluid medium inside the pipeline is weakened. Through the actions of the aspects, the silencing pipeline provided by the invention has the composite functions of mechanical vibration isolation, deformation compensation and in-pipe silencing, and the composition configuration of a fluid conveying pipeline system is simplified. In addition, because the draft tube 5 is flexible and can be fixed at two ends, the damage probability of falling, deformation and the like of the draft tube 5 can be effectively reduced, the reliability of the pipeline is enhanced, the installation and maintenance cost is reduced, and the service life of the pipeline is prolonged.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and is not to be construed as limiting the invention, and any modifications, equivalents, improvements and the like that fall within the spirit and principle of the present invention are intended to be included therein.

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.

Images