Stainless steel corrugated hose and method of making same

Abstract

The application discloses a stainless steel corrugated hose and a preparation method thereof, and relates to the technical field of pipes.The hose comprises a stainless steel inner pipe body, a damping enhancement layer and a stainless steel outer pipe body which are coaxially arranged from inside to outside.The inner pipe body is provided with micro grooves which continuously extend in the axial direction on the inner wall, and the pipe wall of the inner pipe body and the outer pipe body are both provided with continuous corrugations, and the two corrugations are axially staggered by half a wave distance.The damping enhancement layer is filled and bonded between the two pipe bodies, and the thickness thereof is alternately changed along with the corrugation staggering, forming elastic support rings with alternating thickness.The preparation method comprises the following steps: processing micro grooves on the surface of a stainless steel belt, roll-welding to form an inner pipe blank, coating an unvulcanized elastomer material to form a damping layer embryo after annealing, coating an outer pipe blank to obtain a three-layer composite pipe blank, and finally forming corrugations on the inner and outer pipe blanks and vulcanizing by heating, so that the damping layer is solidified and bonded, and the elastic back pressure provided by the damping layer embryo is used to protect the micro grooves from being damaged.

Description

Technical Field

[0001] This invention relates to the field of pipeline technology, and more specifically, to a stainless steel corrugated hose and its manufacturing method. Background Technology

[0002] Stainless steel corrugated hoses are widely used in gas, water supply, HVAC, and industrial piping systems due to their flexibility and corrosion resistance. Existing stainless steel corrugated hoses are typically made by rolling and welding a single layer of austenitic stainless steel strip into a round tube, which is then hydraulically or mechanically rolled to form the corrugations.

[0003] The above-mentioned single-layer corrugated pipes have the following shortcomings in use: at high flow velocities, the turbulence effect of the fluid inside the pipe causes a large pressure loss along the pipe; under repeated bending and pressure alternation conditions, stress concentration is significant at the crests and troughs of the corrugations, which easily leads to fatigue cracks; the single-layer thin-walled structure has low damping, and pressure pulsation and mechanical vibration are transmitted along the pipe body and radiate noise outwards; once the single-layer pipe wall is perforated, it loses its sealing performance and lacks secondary protection.

[0004] Furthermore, while microgrooves on the inner wall of the tube can reduce flow resistance, corrugated hose forming requires significant plastic deformation. If grooves are pre-machined on the strip, they will be destroyed during corrugation. If grooves are machined on the inner wall of the finished tube, the cutting tool cannot enter the narrow corrugated cavity. Therefore, retaining drag-reducing microstructures on the inner wall of stainless steel corrugated hoses has not been achieved, resulting in a technical bottleneck in flow resistance control for existing products. Summary of the Invention

[0005] This invention provides a stainless steel corrugated hose, which solves the technical problems of high flow resistance, short fatigue life, insufficient damping and weak protection of single-layer corrugated hoses in related technologies.

[0006] This invention discloses a stainless steel corrugated flexible hose, comprising a stainless steel inner tube, a damping reinforcement layer, and a stainless steel outer tube, arranged coaxially from radially inward to radially outward. The inner tube has continuously distributed corrugations along its axial direction on its wall, and the outer tube also has continuously distributed corrugations along its axial direction on its wall. The damping reinforcement layer fills the space between the radially outer wall of the inner tube and the radially inner wall of the outer tube, and is bonded and fixed to both the inner and outer tubes. Multiple microgrooves extending continuously in a spiral pattern along the axial direction are formed on the inner wall surface of the inner tube.

[0007] Furthermore, the corrugations of the stainless steel inner tube and the stainless steel outer tube are staggered along the tube axial direction, with the corrugations of the inner tube offset by half a wave pitch relative to the corrugations of the outer tube. The inner wave crest of the inner tube is radially aligned with the outer wave trough of the outer tube, and vice versa. The thickness of the damping reinforcement layer alternates along the tube axial direction, being thinner in the section where the inner wave crest and outer wave trough are aligned, and thicker in the section where the inner wave trough and outer wave crest are aligned, forming an elastic support ring with alternating thicknesses.

[0008] Furthermore, the corrugations on the stainless steel inner tube and the stainless steel outer tube are annular corrugations, and the annular corrugations are periodically distributed in concentric rings along the axial direction of the tube.

[0009] Furthermore, the corrugations on the stainless steel inner tube and the stainless steel outer tube are spiral corrugations, which extend continuously in a spiral shape along the axial direction of the tube.

[0010] Furthermore, the cross-section of the microgroove is V-shaped, and the apex angle of the V-shaped microgroove is 45 degrees to 90 degrees.

[0011] Furthermore, the cross-section of the microgroove is trapezoidal or arc-shaped.

[0012] Furthermore, the depth of the microgrooves is 0.05 to 0.5 mm, and the distance between two adjacent microgrooves is 0.1 to 1 mm.

[0013] Furthermore, the damping reinforcement layer is composed of a polymer elastomer, which is hydrogenated nitrile rubber, fluororubber, or polyurethane. The polymer elastomer is bonded and fixed to the metal surfaces of the stainless steel inner tube and the stainless steel outer tube by hot vulcanization.

[0014] Furthermore, the damping reinforcement layer is composed of a metal-rubber composite material, which is made of a metal mesh and an elastomer. The metal mesh provides structural support, and the elastomer provides viscoelastic damping.

[0015] This invention discloses a method for preparing a stainless steel corrugated flexible hose, comprising the following steps: On one side of an austenitic stainless steel strip serving as the inner wall of the tube, multiple microgrooves are continuously machined obliquely along the length of the strip, the microgrooves being distributed obliquely in a straight line on the strip surface. The austenitic stainless steel strip with the microgrooves is fed into a tube winding machine, with the microgrooved surface facing the inner side of the tube cavity, and is rolled into a circular tube, with the butt joints welded to form an inner tube blank. The inner tube blank is then bright annealed in a protective atmosphere to eliminate work hardening caused by winding and welding. An uncured elastomer material is uniformly coated onto the radially outer surface of the annealed inner tube blank to form a damping layer. An austenitic stainless steel strip is then coated onto the radially outer side of the damping layer and the butt joints welded to form an outer tube blank, resulting in a three-layer composite tube blank composed of the inner tube blank, the damping layer, and the outer tube blank, arranged coaxially in sequence. The three-layer composite tube blank is placed in a corrugated forming mold, and forming force is applied to the three-layer composite tube blank to form corrugations on the inner tube blank and the outer tube blank simultaneously. At the same time, heating causes the elastomeric material in the damping layer preform to vulcanize and crosslink, and to bond and fix it to the metal surfaces of the inner tube blank and the outer tube blank to form a damping reinforcement layer. During the heat vulcanization process, the damping layer preform applies a uniform elastic back pressure to the outer wall of the inner tube blank, so that the forming force is evenly distributed on the wall surface of the inner tube blank, maintaining the groove shape of the micro-grooves.

[0016] This invention employs a three-layer coaxial nested structure consisting of an inner tube, a damping reinforcement layer, and an outer tube. Combined with the spiral microgrooves on the inner wall of the inner tube and the staggered arrangement of the inner and outer corrugations, it solves the technical problems of existing single-layer stainless steel corrugated hoses, such as excessive flow resistance, stress concentration at the crests and troughs, vibration and noise transmission along the tube, loss of sealing upon perforation of the single-layer tube wall, and the inability to retain drag-reducing microstructures on the inner wall of the corrugated hose. It achieves the technical effects of reducing fluid friction resistance along the hose, dispersing and transmitting stress between the two tube walls, attenuating the vibration amplitude of the tube and reducing outward radiated noise, providing secondary leak protection, and retaining spiral microgrooves on the inner wall of the stainless steel corrugated hose. Attached Figure Description

[0017] Figure 1 This is an isometric drawing of the assembly of the stainless steel corrugated hose of the present invention.

[0018] Figure 2 This is a longitudinal sectional view of the stainless steel corrugated hose of the present invention.

[0019] Figure 3 This is a cross-sectional view of the stainless steel corrugated hose of the present invention.

[0020] Figure 4 This is a schematic diagram of the micro-groove structure of the present invention.

[0021] In the figure: Stainless steel inner tube body-1, inner wave peak-1a, inner wave valley-1b, micro groove-11, damping reinforcement layer-2, stainless steel outer tube body-3, outer wave peak-3a, outer wave valley-3b. Detailed Implementation

[0022] Stainless steel corrugated hoses are widely used in gas, water supply, HVAC, and industrial piping systems due to their flexibility and corrosion resistance. Existing stainless steel corrugated hoses are typically made by rolling and welding a single layer of austenitic stainless steel strip into a round tube, which is then hydraulically or mechanically rolled to form the corrugations. This type of single-layer corrugated pipe has the following drawbacks in use: First, at high flow velocities, boundary layer separation and turbulence effects cause significant pressure loss along the pipe, increasing energy consumption. Second, under repeated bending and pressure alternation conditions, stress concentration is significant at the crests and troughs of the corrugations, making them prone to fatigue cracks and leaks. Third, the single-layer thin-walled structure has low damping, allowing pressure pulsations and mechanical vibrations to be transmitted along the pipe and radiate noise outwards. Fourth, once the single-layer pipe wall is damaged or corroded and perforated, it loses its sealing performance, lacking secondary protection. In addition, although microgrooves 11 can reduce flow resistance when the inner wall of the tube is set, the corrugated hose forming process requires a large plastic deformation. If the grooves are pre-machined on the strip, the grooves will be destroyed during corrugation. If the grooves are machined on the inner wall of the finished tube, the cutting tool cannot enter the narrow corrugated cavity. Therefore, it has not been possible to retain drag-reducing microstructures on the inner wall of the corrugated hose.

[0023] According to an embodiment of this invention, a stainless steel corrugated flexible hose includes a stainless steel inner tube 1, a damping reinforcement layer 2, and a stainless steel outer tube 3, arranged coaxially from radially inner to radially outer. The stainless steel inner tube 1 is a stainless steel circular tube with continuously distributed corrugations formed on its wall along the tube's axial direction. The stainless steel outer tube 3 is also a stainless steel circular tube with continuously distributed corrugations formed on its wall along the tube's axial direction. The damping reinforcement layer 2 fills the corrugated gap between the radially outer wall of the stainless steel inner tube 1 and the radially inner wall of the stainless steel outer tube 3. The radially inner surface of the damping reinforcement layer 2 is bonded and fixed to the radially outer surface of the stainless steel inner tube 1, and the radially outer surface of the damping reinforcement layer 2 is bonded and fixed to the radially inner surface of the stainless steel outer tube 3. The three layers form an integrated coaxial nested tube. Multiple microgrooves 11 extending continuously in a spiral pattern along the tube's axial direction are formed on the inner wall surface of the stainless steel inner tube 1. The microgrooves 11 are groove structures formed on the inner wall of the stainless steel inner tube 1, with a depth of 0.05 to 0.5 mm and a spacing of 0.1 to 1 mm between adjacent microgrooves 11. The microgrooves 11 are in direct contact with the fluid inside the tube and are used to constrain the spanwise vortex structure in the near-wall turbulent boundary layer, suppress the sudden uplift of high-speed fluid strips, and reduce the frictional resistance along the fluid path.

[0024] In some embodiments, the corrugations on the stainless steel inner tube 1 and the stainless steel outer tube 3 are annular corrugations, which are periodically distributed in concentric rings along the axial direction of the tube.

[0025] In some embodiments, the corrugations on the stainless steel inner tube 1 and the stainless steel outer tube 3 are spiral corrugations, which extend in a continuous spiral shape along the axial direction of the tube.

[0026] In some embodiments, the cross-section of the microgroove 11 is V-shaped.

[0027] In some embodiments, the cross-section of the microgroove 11 is trapezoidal.

[0028] In some embodiments, the cross-section of the microgroove 11 is arc-shaped.

[0029] In some embodiments, the damping reinforcement layer 2 is composed of a polymeric elastomer. The polymeric elastomer is one of hydrogenated nitrile rubber, fluororubber, or polyurethane. The polymeric elastomer is bonded and fixed to the metal surfaces of the stainless steel inner tube 1 and the stainless steel outer tube 3 by heat vulcanization.

[0030] In some embodiments, the damping reinforcement layer 2 is composed of a metal-rubber composite material. The metal-rubber composite material is made of a metal mesh and an elastomer, with the metal mesh providing structural support and the elastomer providing viscoelastic damping.

[0031] Furthermore, to create an elastic support structure with alternating thickness between the stainless steel inner tube 1 and the stainless steel outer tube 3, thereby achieving a more uniform stress distribution when the tube is under load, the corrugations of the stainless steel inner tube 1 and the stainless steel outer tube 3 are staggered along the tube's axial direction. The corrugations of the stainless steel inner tube 1 are offset by half a wave pitch relative to the corrugations of the stainless steel outer tube 3 along the axial direction. Under this staggered arrangement, the inner wave crest 1a faces the outer wave trough 3b radially, with a smaller radial distance between the two tube walls, resulting in a thinner thickness of the damping reinforcement layer 2 in this section; conversely, the inner wave trough 1b faces the outer wave crest 3a radially, with a larger radial distance between the two tube walls, resulting in a thicker thickness of the damping reinforcement layer 2 in this section. The thickness of the damping reinforcement layer 2 alternates along the tube's axial direction, forming alternating thick and thin elastic support rings between adjacent corrugations. When the pipe body is subjected to bending or axial loads, the stainless steel inner pipe body 1 and the stainless steel outer pipe body 3 work together to bear the load through staggered corrugations and damping reinforcement layer 2. The load is distributed and transferred between the two pipe walls, avoiding stress concentration at the inner wave peak 1a or inner wave trough 1b of a single pipe layer.

[0032] Furthermore, to more effectively suppress the spanwise vortex structure of near-wall turbulence, the cross-section of the micro-groove 11 is V-shaped, with an apex angle of 45 to 90 degrees. The V-shaped cross-section of the micro-groove 11 simulates the surface microstructure of shark skin dermal scales. Its sharp bottom can limit the spanwise scale of the spanwise vortex, confining it within the micro-groove 11 and preventing it from expanding outwards from the wall. This suppresses the sudden upward movement of high-speed fluid strips near the wall towards the center of the flow channel, weakens turbulent momentum exchange, and reduces frictional resistance along the flow path.

[0033] It should be noted that the damping reinforcement layer 2 simultaneously performs two functions during pipe operation: vibration reduction and energy dissipation, and secondary sealing. Regarding vibration reduction and energy dissipation, when there are pressure pulsations in the fluid inside the pipe or when the pipe is subjected to external mechanical vibration, the vibration generated by the stainless steel inner pipe wall 1 is transmitted to the damping reinforcement layer 2 through the bonding interface. Due to the slight relative displacement between the stainless steel inner pipe 1 and the stainless steel outer pipe 3 during vibration, the damping reinforcement layer 2 undergoes viscoelastic shear deformation between the two pipe walls, converting the mechanical energy of the vibration into heat energy for dissipation, thereby attenuating the vibration amplitude transmitted to the stainless steel outer pipe 3 and reducing the noise radiated outward from the pipe. Regarding secondary sealing, when the stainless steel outer pipe 3 is perforated due to external mechanical damage or corrosion, the damping reinforcement layer 2, relying on the sealing properties of the elastomeric material, acts as a sealing barrier, preventing the medium inside the pipe from leaking out through the damaged area of ​​the stainless steel outer pipe 3. At this time, the stainless steel inner pipe 1 continues to withstand the internal fluid pressure and maintain the sealing integrity of the flow channel, thus providing secondary leak-proof protection.

[0034] It should be understood that both the stainless steel inner tube 1 and the stainless steel outer tube 3 are flexible deformable components, capable of being compressed or stretched along the tube's axial direction, and can be bent and deformed in a plane including the tube's axis. After the three layers are bonded together, the overall structure retains the flexible characteristics of the stainless steel corrugated hose. When the tube is bent or undergoes axial expansion and contraction, the microgrooves 11 deform along with the wall of the stainless steel inner tube 1, experiencing only a slight stretch, thus preserving the groove shape of the microgrooves 11.

[0035] This embodiment also provides a method for preparing the above-mentioned stainless steel corrugated hose, including the following steps.

[0036] Step 1: Pre-fabrication of grooved stainless steel strip. Take a cleaned austenitic stainless steel strip and, on one side of the austenitic stainless steel strip that will serve as the inner wall of the stainless steel inner tube 1, continuously and obliquely machine densely arranged micro-grooves 11 along the length of the strip. The micro-grooves 11 are distributed obliquely in a straight line on the surface of the strip, ensuring that after the austenitic stainless steel strip is subsequently rolled into a round tube, the micro-grooves 11 are continuously spirally distributed on the inner wall of the stainless steel inner tube 1. After processing, the strip is cleaned and dried.

[0037] In some embodiments, the microgrooves 11 are processed by laser engraving, using an ultraviolet laser marking machine to continuously engrave on the surface of the strip, and the depth of the microgrooves 11 is controlled by adjusting the laser power and scanning speed.

[0038] In some embodiments, the micro-grooves 11 are processed by chemical etching, where a mask is covered on the surface of the strip and then chemical etching is performed to form the micro-grooves 11.

[0039] Step 2: Inner tube blank rolling. The grooved austenitic stainless steel strip obtained in Step 1 is fed into a continuous tube rolling unit, with the grooved surface facing the inside of the tube cavity, and rolled into a round tube. The butt joints of the strip are welded together using laser welding to form a longitudinal weld. The excess weld height is then ground smooth to obtain the inner tube blank.

[0040] Step 3, Bright Annealing. The inner tube blank is bright annealed in a protective atmosphere to eliminate work hardening caused by rolling and welding, restore the plasticity of the inner tube blank, and enable the inner tube blank to withstand the plastic deformation required for subsequent corrugation forming.

[0041] Step 4: Applying the damping layer preform. A layer of uncured elastomer material is uniformly applied to the radial outer surface of the annealed inner tube blank to form the damping layer preform. The damping layer preform is tightly adhered to the outer wall of the inner tube blank, providing an elastomer preform for subsequent corrugation forming and vulcanization bonding.

[0042] In some embodiments, the coating method is extrusion winding, in which the elastomer compound is extruded through an extruder and spirally wound onto the outer surface of the inner tube blank.

[0043] In some embodiments, the covering method is tape wrapping, in which pre-made elastomer tape is tightly wrapped around the outer surface of the inner tube blank.

[0044] In some embodiments, the coating method is coating, in which an elastomer material is uniformly coated onto the outer surface of the inner tube blank.

[0045] Step 5: Coating the outer tube blank. A layer of austenitic stainless steel strip is tightly wrapped around the radial outer side of the damping layer blank, and the butt joints of the austenitic stainless steel strip are laser welded together to form the outer tube blank. At this point, a three-layer composite tube blank is obtained, consisting of the inner tube blank, the damping layer blank, and the outer tube blank arranged coaxially in sequence.

[0046] Step Six: Overall Corrugation Forming and Vulcanization Curing. The three-layer composite tube blank is placed in the mold of the corrugation forming equipment. Forming force is applied to the three-layer composite tube blank simultaneously using both the inner and outer molds, forming corrugations on the inner and outer tube blanks in one step. Simultaneously, the three-layer composite tube blank is heated, causing the elastomer material in the damping layer to vulcanize and cross-link, bonding and fixing it to the metal surfaces of the inner and outer tube blanks, forming the damping reinforcement layer 2. The heating temperature and holding time are determined based on the vulcanization characteristics of the selected elastomer material.

[0047] In some embodiments, the corrugation forming method is mechanical rolling, which uses an inner mold and an outer mold with an annular corrugated profile to roll the three-layer composite tube blank.

[0048] In some embodiments, the corrugation forming method is hydraulic expansion, in which high-pressure liquid is introduced into the cavity, and the three-layer composite tube blank is bonded to the outer mold by hydraulic pressure to form corrugations.

[0049] Furthermore, to protect the microgrooves 11 on the inner wall of the stainless steel inner tube 1 from being flattened or torn during the corrugation process, the corrugated profile of the inner mold corresponds to the target corrugated shape of the stainless steel inner tube 1, and the corrugated profile of the outer mold corresponds to the target corrugated shape of the stainless steel outer tube 3. The trough sections of the inner mold and the crest sections of the outer mold are axially offset by half a corrugation pitch. By controlling the forming pressure and mold gap, the inner tube blank undergoes primarily tensile deformation during corrugation, while the microgrooves 11 only experience slight stretching and are not flattened. Simultaneously, the damping layer sandwiched between the inner and outer tube blanks remains elastic during heat vulcanization, applying a uniform elastic back pressure to the outer wall of the inner tube blank. This elastic back pressure radially supports the inner tube wall, ensuring the forming force is evenly distributed across the inner tube blank wall, preventing localized pressure concentration that could lead to deformation of the microgrooves 11, thus maintaining the shape of the microgrooves 11.

[0050] Step 7, Solution Treatment. The corrugated and vulcanized pipe body is subjected to a bright solution treatment, followed by rapid cooling to eliminate residual forming stress and restore the corrosion resistance of stainless steel, resulting in the finished stainless steel corrugated hose.

[0051] The stainless steel corrugated hose of this embodiment adopts a three-layer coaxial nested structure of stainless steel inner tube 1, damping reinforcement layer 2 and stainless steel outer tube 3. Combined with the spiral micro-groove 11 on the inner wall of stainless steel inner tube 1 and the staggered arrangement of inner and outer corrugations, it solves the shortcomings of existing single-layer corrugated hoses in terms of flow resistance, fatigue life, vibration noise and safety.

[0052] In terms of reducing fluid resistance, because the inner wall of the stainless steel inner tube 1 is provided with micro-grooves 11 that extend continuously in a spiral along the axial direction, the V-shaped cross section of the micro-grooves 11 constrains the spanwise vortex structure in the turbulent boundary layer near the wall, so that the spanwise vortex is confined inside the micro-grooves 11, suppressing the sudden upward movement of high-speed fluid strips and weakening the turbulent momentum exchange in the near-wall region, the frictional resistance along the fluid is reduced, and the conveying flow rate can be increased under the same pressure difference.

[0053] In terms of improving fatigue life, because the stainless steel inner tube 1 and the stainless steel outer tube 3 are bonded together by the damping reinforcement layer 2 to form a double-layer load-bearing structure, the staggered arrangement of the corrugations of the stainless steel inner tube 1 and the stainless steel outer tube 3 makes the damping reinforcement layer 2 form an elastic support ring with alternating thicknesses. When the tube body is subjected to bending and alternating pressure loads, the stress is dispersed and transmitted between the two tube walls through the elastic support ring, which overcomes the stress concentration problem at the inner wave peak 1a and inner wave valley 1b in the single-layer corrugated pipe, thus extending the fatigue life of the tube body.

[0054] In terms of vibration reduction and noise reduction, the damping reinforcement layer 2 undergoes viscoelastic shear deformation when the stainless steel inner tube 1 and the stainless steel outer tube 3 produce relative micro-displacement, converting the vibration mechanical energy into heat energy dissipation. This overcomes the problem of insufficient damping of a single-layer thin-walled tube causing vibration and noise to be transmitted along the tube, thus attenuating the vibration amplitude of the tube and reducing the noise radiated outward.

[0055] In terms of safety protection, since the damping reinforcement layer 2 is filled between the stainless steel inner tube 1 and the stainless steel outer tube 3 as an elastic sealing barrier, even if the stainless steel outer tube 3 is perforated due to external damage, the damping reinforcement layer 2 can still prevent the medium inside the tube from leaking out, and the stainless steel inner tube 1 continues to maintain the sealing integrity of the flow channel, overcoming the defect that the single-layer pipe wall loses its sealing performance when perforated, thus providing secondary leakage protection.

[0056] In terms of manufacturing process, because the microgrooves 11 are pre-machined on the surface of the flat austenitic stainless steel strip, the difficulty of machining the microgrooves 11 in the narrow inner cavity of the finished stainless steel corrugated hose is avoided. During the corrugation forming process, because the damping layer blank applies uniform elastic back pressure to the outer wall of the inner tube blank, it supports the inner tube wall in the radial direction and makes the forming force evenly distributed, overcoming the problem that the microgrooves 11 are flattened or torn due to plastic deformation during corrugation forming. Therefore, the technical problem of not being able to retain the drag-reducing microstructure on the inner wall of the stainless steel corrugated hose is solved.

[0057] The embodiments of the present invention have been described above. However, the embodiments are not limited to the specific implementation methods described above. The specific implementation methods described above are merely illustrative and not restrictive. Those skilled in the art can make more equivalent embodiments under the guidance of the present embodiments, and all of them are within the protection scope of the present embodiments.

Claims

1. A stainless steel corrugated flexible hose, characterized in that, include: A stainless steel inner tube (1), a damping reinforcement layer (2), and a stainless steel outer tube (3) are arranged coaxially from the radial inner side to the radial outer side. The stainless steel inner tube (1) has continuously distributed corrugations along the axial direction on its tube wall, and the stainless steel outer tube (3) has continuously distributed corrugations along the axial direction on its tube wall. The damping reinforcement layer (2) is filled between the radial outer wall of the stainless steel inner tube (1) and the radial inner wall of the stainless steel outer tube (3), and is bonded and fixed to the stainless steel inner tube (1) and the stainless steel outer tube (3) respectively. Multiple micro-grooves (11) extending continuously in a spiral along the axial direction are opened on the inner wall surface of the stainless steel inner tube (1).

2. The stainless steel corrugated hose according to claim 1, characterized in that, The corrugations of the stainless steel inner tube (1) and the stainless steel outer tube (3) are staggered along the tube axis. The corrugations of the stainless steel inner tube (1) are offset by half a wave pitch relative to the corrugations of the stainless steel outer tube (3) along the axial direction. The inner wave peak (1a) of the stainless steel inner tube (1) is radially aligned with the outer wave valley (3b) of the stainless steel outer tube (3), and the inner wave valley (1b) of the stainless steel inner tube (1) is radially aligned with the outer wave peak (3a) of the stainless steel outer tube (3). The thickness of the damping reinforcement layer (2) varies alternately along the tube axis. The thickness is thinner in the section where the inner wave peak (1a) and the outer wave valley (3b) are aligned, and thicker in the section where the inner wave valley (1b) and the outer wave peak (3a) are aligned, forming an elastic support ring with alternating thicknesses.

3. The stainless steel corrugated hose according to claim 1 or 2, characterized in that, The corrugations on the stainless steel inner tube (1) and the stainless steel outer tube (3) are annular corrugations, which are periodically distributed in concentric rings along the axial direction of the tube.

4. The stainless steel corrugated hose according to claim 1 or 2, characterized in that, The corrugations on the stainless steel inner tube (1) and the stainless steel outer tube (3) are spiral corrugations, which extend continuously in a spiral shape along the axial direction of the tube.

5. The stainless steel corrugated hose according to claim 1, characterized in that, The cross-section of the micro-groove (11) is V-shaped, and the apex angle of the V-shaped micro-groove (11) is 45 degrees to 90 degrees.

6. The stainless steel corrugated hose according to claim 1, characterized in that, The damping reinforcement layer (2) is composed of a polymer elastomer, which is hydrogenated nitrile rubber, fluororubber or polyurethane. The polymer elastomer is bonded and fixed to the metal surfaces of the stainless steel inner tube (1) and the stainless steel outer tube (3) by hot vulcanization.

7. The stainless steel corrugated hose according to claim 1, characterized in that, The damping reinforcement layer (2) is composed of a metal-rubber composite material, which is made of a metal wire mesh and an elastomer. The metal wire mesh provides structural support, and the elastomer provides viscoelastic damping.

8. The stainless steel corrugated hose according to claim 1 or 5, characterized in that, The depth of the microgroove (11) is 0.05 to 0.5 mm, and the distance between two adjacent microgrooves (11) is 0.1 to 1 mm.

9. A method for preparing a stainless steel corrugated hose as described in any one of claims 1 to 8, characterized in that, Includes the following steps: On one side of the austenitic stainless steel strip that serves as the inner wall of the inner tube, multiple micro-grooves (11) are continuously machined obliquely along the length of the strip. The micro-grooves (11) are distributed obliquely in a straight line on the surface of the strip. The austenitic stainless steel strip with the micro-grooves (11) is fed into the tube rolling machine, with the micro-grooves (11) facing the inside of the tube cavity, rolled into a round tube and the butt joint edges are welded together to form an inner tube blank. The inner tube blank is bright annealed in a protective atmosphere to eliminate work hardening caused by tube rolling and welding; an uncured elastomer material is uniformly coated on the radial outer surface of the annealed inner tube blank to form a damping layer. An austenitic stainless steel strip is wrapped around the radial outer side of the damping layer blank and the butt joint is welded to form an outer tube blank, resulting in a three-layer composite tube blank composed of the inner tube blank, the damping layer blank, and the outer tube blank in sequence and coaxially. The three-layer composite tube blank is placed in a corrugated forming mold, and a forming force is applied to the three-layer composite tube blank to form corrugations on the inner tube blank and the outer tube blank at the same time. Simultaneously, heating is used to vulcanize and crosslink the elastomeric material in the damping layer blank and bond and fix it to the metal surfaces of the inner tube blank and the outer tube blank to form a damping reinforcement layer (2). During the heat vulcanization process, the damping layer blank applies a uniform elastic back pressure to the outer wall of the inner tube blank, so that the forming force is evenly distributed on the wall surface of the inner tube blank and the groove shape of the micro groove (11) is maintained.

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