High-strength stainless steel seamless pipe fitting

Abstract

The invention relates to the technical field of seamless pipes, in particular to a high-strength stainless steel seamless pipe fitting which comprises an outer pipe body and lining pipe bodies arranged in the outer pipe body, the upper lining pipe body and the lower lining pipe body are symmetrically arranged in a pipe cavity of the outer pipe body, and supporting assemblies are arranged on the two lining pipe bodies. The supporting assembly comprises supporting rings connected to the opposite ends of the two liner tube bodies, the supporting rings are made of spring plate materials and bent towards the centers of the liner tube bodies, shrinkage holes coinciding with the axes of the liner tube bodies are formed in the bent tail ends of the supporting rings, and the shrinkage holes are communicated with the supporting rings. The supporting assembly further comprises reinforcing steel bars connected to the pipe cavity wall of the liner pipe body, shrinkage of the shrinkage holes is reduced, namely the axial force is further decomposed towards the axis direction, and when the outer pipe body deals with the axial acting force, the strength performance is further improved.

Description

Technical Field

[0001] The present invention relates to the technical field of seamless pipes, in particular to a high-strength stainless steel seamless pipe fitting. Background Art

[0002] Seamless pipes are often used as supports in the construction industry. Therefore, in addition to corrosion resistance, they also have high requirements for support strength. Seamless pipes do not exist in isolation in the construction industry. According to construction requirements, they are often constructed from horizontal, vertical, and cross-shaped pipes to form pipe components, which support the steel structure and provide strength support for the steel structure. Therefore, for steel pipe structures, strength resistance comes not only from top support, but also from lateral shear forces in cross-shaped pipes.

[0003] In order to improve the strength of steel pipes, the existing treatment method is to change the performance of steel pipes through heat treatment. However, for the above-mentioned steel structures built with steel pipes, they cannot meet the strength requirements when dealing with multi-directional loads. Summary of the Invention

[0004] In order to solve the above problems, the present invention provides a high-strength stainless steel seamless pipe fitting, comprising an outer pipe body and a liner body arranged in the outer pipe body, the liner body is in two places, upper and lower, and is symmetrically arranged in the tube cavity of the outer pipe body, and a support assembly is provided on the two liner bodies, and the support assembly includes a support ring connected to the opposite ends of the two liner bodies, the support ring is made of spring plate material, the support ring is bent toward the center of the liner body, and a shrinkage hole coinciding with the axis of the liner body is provided on the bent end of the support ring, the support assembly also includes steel bars connected to the tube cavity wall of the liner body, the steel bars are a plurality of annular arrays and extend horizontally along the radial direction of the liner body and then connected to the tube cavity inner wall of the liner body, and the opposite ends of the plurality of steel bars are welded together. The first nut, the center of the first nut and the center of the shrinkage hole are on the same axis, the support assembly also includes a screw installed on the first nut, the other end of the screw passes through the shrinkage hole and is installed with a fixing plate through the second nut, the inner surface of the fixing plate is attached to the outer end surface of the support ring, when the screw rotates and rises, the support ring is dragged by the fixing plate to bend radially toward the axial direction of the liner body, and the shrinkage hole is radially contracted; conversely, when the screw rotates and descends, the fixing plate is moved away from the support ring, and the support ring is moved away from the shrinkage hole to radially bend and recover, and the shrinkage hole is radially expanded. The outer tube body is also filled with a spring, and the two ends of the spring extend toward and approach the two liner bodies, and the two ends of the spring are elastically supported on the opposite surfaces of the two support rings.

[0005] As a further preferred embodiment, the outer ends of the two screw rods are provided with insertion holes, the insertion holes are elliptical holes, and the elliptical hole contours of the insertion holes are provided with rounded corners.

[0006] As a further preferred embodiment, annular grooves are provided on opposite surfaces of the two support rings, and the connecting ends of the spring and the support rings are in contact with the annular grooves.

[0007] As a further preferred embodiment, the diameter of the spring is smaller than the diameter of the lumen of the outer tube body, so that a gap is left between the spring and the lumen wall of the outer tube body.

[0008] As a further preferred embodiment, the part of the support ring connected to the end of the liner body is provided with a first bend portion, the first bend portion is U-shaped, and the bending direction is bent away from the cavity wall direction of the outer tube body, the end of the first bend portion is provided with a second bend portion, the second bend portion is bent toward the cavity wall direction of the outer tube body, the end of the second bend portion is provided with a third bend portion, and the third bend portion is bent toward the axial direction of the liner body.

[0009] As a further preferred embodiment, a circle of dividing grooves is provided on the support ring along the annular array of the third bend, one end of the dividing grooves is communicated with the shrinkage hole, and the other end of the dividing grooves passes through the first bend and the second bend, so that the support ring is divided into a plurality of support units, and the dividing grooves gradually narrow toward one end of the shrinkage hole. When the fixing plate detaches from the inner surface of the support unit, the support unit automatically deflects toward the middle of the axis of the outer tube body by utilizing the material properties of its spring plate.

[0010] As a further preferred embodiment, a contact surface of the fixing plate with the supporting unit is provided with a tapered surface, and the tapered surface gradually tilts toward the edge of the fixing plate, so that the thickness of the fixing plate gradually becomes thinner toward the edge.

[0011] As a further preferred embodiment, the outer end of one of the liner bodies extends beyond one end of the outer tube body, and friction particles are provided on the tube wall of the extending end of the liner body; the outer end of the other liner body extends beyond the other end of the outer tube body, and friction particles are also provided on the tube wall of the extending end of the other liner body, and the friction particles protrude from the tube wall of the liner body.

[0012] The beneficial effects of the present invention compared to the prior art are:

[0013] 1. When the load force generated comes from the axial direction of the outer tube body, in addition to obtaining strength support through the outer tube body and the external tubes welded at both ends of the outer tube body, the inner side of the outer tube body will form strength support with the assistance of the liner body to prevent the outer tube body from bending and deforming, so that the strength performance of the outer tube body can be further improved when dealing with the force from the axis. In addition, the spring will also decompose the force in the axial direction, so that the outer tube body's strength support capacity for the force on the axis can be further improved; when the load comes from the oblique or lateral direction of the outer tube body, it will be supported radially by the outer tube body and the liner body, and the liner body will further improve the outer tube body's ability to cope with shear force. Of course, the spring will also decompose the shear force. In addition to improving the strength support through the above-mentioned outer tube body, liner body and spring, the steel bars will further improve the radial strength capacity of the liner body, and the support ring will further improve the axial strength capacity of the liner body. In particular, when the axial force acts on the liner body, once the liner body moves axially, it will use the inner end to push the support ring, and the support ring will push the spring to compress the spring. At the same time, the bent end of the support ring will bend upward toward one end of the contraction hole to buffer and resolve the axial force, so as to reduce the degree of damage to the outer tube body and the liner body, and further improve the strength performance of the outer tube body when responding to the axial force.

[0014] 2. The axial force acting on the outer tube body is supported by the strength of the outer tube body, and is transmitted to the liner body under the friction of the friction particles. The liner body will descend along the outer tube body, and the support ring will be pushed by the bottom end of the liner body. The bottom of the support ring is restricted by the elasticity of the spring, and after buffering, the third bend drives the first bend and the second bend to bend elastically toward the axial direction. At this time, the shrinkage hole shrinks and becomes smaller, and the shrinkage of the shrinkage hole is equivalent to further dissipating the axial force toward the axial direction, so that the strength performance of the outer tube body is further improved when responding to the axial force. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] Figure 1 A schematic diagram of the overall structure of a high-strength stainless steel seamless pipe provided by an embodiment of the present invention;

[0016] Figure 2 A schematic diagram of a high-strength stainless steel seamless pipe provided by an embodiment of the present invention with the outer pipe body removed;

[0017] Figure 3 A schematic diagram of a high-strength stainless steel seamless pipe with only one liner body provided in an embodiment of the present invention;

[0018] Figure 4 A high-strength stainless steel seamless pipe provided by the embodiment of the present invention is composed of Figure 1The schematic diagram after the section is drawn;

[0019] Figure 5 A high-strength stainless steel seamless pipe provided by the embodiment of the present invention is composed of Figure 4 The enlarged schematic diagram of part A is shown;

[0020] Figure 6 A high-strength stainless steel seamless pipe provided by the embodiment of the present invention is composed of Figure 4 A schematic diagram from another perspective;

[0021] Figure 7 A high-strength stainless steel seamless pipe provided by the embodiment of the present invention is composed of Figure 6 Enlarged schematic diagram of part B.

[0022] In the figure: 1. Outer tube body; 2. Liner body; 3. Support ring; 4. Shrinkage hole; 5. Steel bar; 6. First nut; 7. Screw; 8. Second nut; 9. Fixing plate; 10. Spring; 11. Socket; 12. Fillet; 13. Ring groove; 14. Gap; 15. First bend; 16. Second bend; 17. Third bend; 18. Dividing groove; 19. Support unit; 20. Conical surface; 21. Friction particles. DETAILED DESCRIPTION

[0023] The above and other embodiments and advantages of the present invention are clearly and completely described below in conjunction with the accompanying drawings. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments.

[0024] In one embodiment, Figure 1-Figure 7 As shown:

[0025] The present embodiment provides a high-strength stainless steel seamless pipe fitting, comprising an outer pipe body 1 and a liner pipe body 2 arranged in the outer pipe body 1, the liner pipe body 2 is in two upper and lower places, and is symmetrically arranged in the tubular cavity of the outer pipe body 1, and a support assembly is provided on the two liner pipe bodies 2, and the support assembly comprises a support ring 3 connected to the opposite ends of the two liner pipe bodies 2, the support ring 3 is made of spring plate material, the support ring 3 is bent toward the center of the liner pipe body 2, and a shrinkage hole 4 is provided on the bent end of the support ring 3 that coincides with the axis of the liner pipe body 2, the support assembly also comprises a steel bar 5 connected to the tubular cavity wall of the liner pipe body 2, the steel bar 5 is a plurality of steel bars in an annular array and extends horizontally along the radial direction of the liner pipe body 2 and is connected to the tubular inner wall of the liner pipe body 2, and the opposite ends of the plurality of steel bars 5 are welded together with a first Nut 6, the center of the first nut 6 and the center of the shrinkage hole 4 are on the same axis, the support assembly also includes a screw 7 installed on the first nut 6, the other end of the screw 7 passes through the shrinkage hole 4 and is installed with a fixing plate 9 through the second nut 8, the inner surface of the fixing plate 9 is fitted on the outer end face of the support ring 3, when the screw 7 rotates and rises, the support ring 3 is dragged by the fixing plate 9 to bend radially toward the axial direction of the liner body 2, and the shrinkage hole 4 is radially contracted; conversely, when the screw 7 rotates and descends, the fixing plate 9 is moved away from the support ring 3, and the support ring 3 is moved away from the shrinkage hole 4 to restore radial bending, and the shrinkage hole 4 is radially expanded. The outer tube body 1 is also filled with a spring 10, and the two ends of the spring 10 extend toward and approach the two liner bodies 2, and the two ends of the spring 10 are elastically supported on the opposite surfaces of the two support rings 3.

[0026] like Figure 5 As shown, annular grooves 13 are formed on the opposing surfaces of the two support rings 3, and the connecting ends of the spring 10 and the support rings 3 contact the annular grooves 13. The diameter of the spring 10 is smaller than the diameter of the lumen of the outer tube body 1, so that a gap 14 is left between the spring 10 and the lumen wall of the outer tube body 1. The upper and lower ends of the spring 10 are positioned between the two support rings 3 through the annular grooves 13. When the spring 10 is compressed to reduce vibration, the gap 14 ensures that the compression is effective.

[0027] As a further preference, the part of the support ring 3 connected to the end of the liner body 2 is provided with a first bend 15, the first bend 15 is U-shaped, and the bending direction is away from the cavity wall direction of the outer tube body 1, the end of the first bend 15 is provided with a second bend 16, the second bend 16 is bent toward the cavity wall direction of the outer tube body 1, and the end of the second bend 16 is provided with a third bend 17, the third bend 17 is bent toward the axial direction of the liner body 2.

[0028] like Figure 1As shown, the outer end of one liner body 2 exceeds one end of the outer tube body 1, and friction particles 21 are provided on the tube wall of the exceeding end of the liner body 2. The outer end of another liner body 2 exceeds the other end of the outer tube body 1, and friction particles 21 are also provided on the tube wall of the exceeding end of the other liner body 2. The friction particles 21 protrude from the tube wall of the liner body 2. When the seamless pipe fittings of this structure are actually used, according to the requirements of the steel structure, an external tube can be connected to the outer end (one end or both ends) of the outer tube body 1. The external tube is connected to the steel structure, and the load of the steel structure will inevitably act on the outer tube body 1. The liner body 2 will also be sleeved in the external tube to assist the outer tube body 1 in preventing bending, and will be in friction contact with the inner wall of the tube cavity of the external tube through the friction particles 21. When the load acts on the steel structure and is acted on the external tube by the steel structure, and then the external tube acts on the outer tube body 1 with axial force, in addition to being supported by the strength of the outer tube body 1, the liner body 2 will also share part of the axial force and improve the strength of the outer tube body 1 at the same time. When the axial force has vibration damage, the liner body 2 will also push the support ring 3 to bend elastically to dissipate the axial vibration force.

[0029] Working principle and effect: Figure 1As shown, according to the requirements of steel structure construction, if it is necessary to add external tubes at the upper and lower ends of the outer tube body 1, one end of the external tube is sleeved on the protruding end of the liner body 2. At this time, the tube cavity of the external tube is fixed by the friction particles 21, and then the interface of the external tube is welded together with the same side end of the outer tube body 1. At this time, the two liner bodies 2 are sleeved in the tube cavities of the two external tubes. At this time, the outer tube body 1 is connected between the two external tubes. According to the requirements of steel structure construction, transverse external tubes or oblique external tubes can be installed on the upper and lower external tubes. The other end of the transverse external tube or oblique external tube is installed on another set of pipe fittings of this structure through another set of external tubes according to the requirements of the steel structure. After the steel structure is built, load will be generated. The load force generated comes from the axial direction of the outer tube body 1 on the one hand, in addition to passing through In addition to the strength support provided to the outer tube body 1 and the external tubes welded at both ends of the outer tube body 1, the inner side of the outer tube body 1 will also form strength support with the assistance of the liner body 2 to prevent the outer tube body 1 from bending and deforming, so that the strength performance of the outer tube body 1 can be further improved when dealing with the force from the axis. In addition, the spring 10 will also decompose the force in the axial direction, so that the strength support capacity of the outer tube body 1 for the force on the axis can be further improved; and when the load comes from the oblique or lateral direction of the outer tube body 1 (shear force), it will be radially supported by the outer tube body 1 and the liner body 2, and the liner body 2 will further improve the ability of the outer tube body 1 to cope with the shear force. Of course, the spring 10 will also decompose the shear force. In addition, when the forces in the above two directions (the force in the axial direction and the shear force in the oblique or lateral direction) are reflected on the outer tube body 1, in addition to improving the strength support through the above-mentioned outer tube body 1, the liner body 2 and the spring 10, the steel bar 5 will further improve the radial strength capacity of the liner body 2, and the support ring 3 will further improve the axial strength capacity of the liner body 2. In particular, when the axial force acts on the liner body 2, once the liner body 2 moves axially, it will use the inner end to push the support ring 3, and the support ring 3 will push the spring 10 to compress and buffer the spring 10. At the same time, the bent end of the support ring 3 will bend upward toward one end of the shrinkage hole 4 to buffer and resolve the axial force, so as to reduce the degree of damage to the outer tube body 1 and the liner body 2, so that the strength performance of the outer tube body 1 is further improved when responding to the axial force.

[0030] like Figure 4 、 Figure 5As shown, before the liner body 2 is assembled into the outer tube body 1, the screw rod 7 is rotated through the insertion hole 11 to move the screw rod 7 outward relative to the first nut 6, and the screw rod 7 drags the fixing plate 9 outward, and the fixing plate 9 drags the support ring 3, so that the third bend 17 on the support ring 3 is deflected toward the lumen direction of the liner body 2, and the third bend 17 drives the first bend 15 and the second bend 16 to deflect toward the shrinkage hole 4, and at the same time, the shrinkage hole 4 is reduced. At this time, the diameter surface profile of the first bend 15 and the second bend 16 is smaller than the lumen diameter of the outer tube body 1. At this time, the liner body 2 is pushed into the outer tube body 1. Inside the lumen of the tube body 1, the liner body 2 simultaneously pushes the support ring 3 into the lumen of the outer tube body 1. The screw 7 is loosened in the opposite direction through the insertion hole 11, causing it to move inward relative to the first nut 6. The screw 7 then pushes the fixing plate 9 inward, loosening the tightness between the fixing plate 9 and the third bend 17. The third bend 17 automatically rebounds due to its spring-plate properties, and the third bend brings the first bend 15 and the second bend 16 back to their original position. The shrinkage hole 4 then enlarges, causing the diameter profile of the first bend 15 and the second bend 16 to be automatically tightened against the lumen wall of the outer tube body 1 and locked. This makes it easier to assemble the liner body 2 and support ring 3 into the outer tube body 1. After assembly, the support ring 3 can be automatically locked into the outer tube body 1. In addition, the following technical effects are achieved by utilizing this assembly performance: taking the upper liner body 2 as an example, the axial force acting on the outer tube body 1 is supported by the strength of the outer tube body 1, and will be transmitted to the liner body 2 under the friction of the friction particles 21. The liner body 2 will descend along the outer tube body 1, and the support ring 3 will be pushed by the bottom end of the liner body 2. The bottom of the support ring 3 is elastically restricted by the spring 10, and after buffering, the third bend 17 drives the first bend 15 and the second bend 16 to be elastically bent toward the axial direction. At this time, the shrinkage hole 4 shrinks and becomes smaller, and the shrinkage of the shrinkage hole 4 is equivalent to further dissipating the axial force toward the axial direction, so that the strength performance of the outer tube body 1 is further improved when responding to the axial force.

[0031] like Figure 4 、 Figure 5As shown, the contact surface of the fixing plate 9 with the support unit 19 is provided with a tapered surface 20. The tapered surface 20 gradually slopes toward the edge of the fixing plate 9, causing the thickness of the fixing plate 9 to gradually decrease toward the edge. When the adjusting screw 7 locks the fixing plate 9 toward the third curved portion 17 of the support ring 3, the tapered surface 20 causes the third curved portion 17 to bend toward the axis. The third curved portion 17 then drives the first curved portion 15 and the second curved portion 16 to elastically bend toward the axis. The contour diameter of the first curved portion 15 and the second curved portion 16 is smaller than the inner diameter of the outer tube body 1, facilitating installation of the support ring 3 within the outer tube body 1 along with the liner body 2. When the screw 7 is rotated in the opposite direction and the fixing plate 9 and the conical surface 20 leave the third bend 17, the third bend 17 rebounds and locks the first bend 15 and the second bend 16 on the wall of the outer tube body 1. When the axial force generated by the load carries vibration damage, the liner body 2 and the support ring 3 can move smoothly along the lumen of the outer tube body 1.

[0032] like Figure 3 、 Figure 6 As shown, the support ring 3 is provided with a circular array of dividing grooves 18 along the third curved portion 17. One end of the dividing grooves 18 communicates with the contraction hole 4, and the other end of the dividing grooves 18 extends through the first curved portion 15 and the second curved portion 16, thereby dividing the support ring 3 into a plurality of support units 19. The dividing grooves 18 gradually narrow toward one end of the contraction hole 4. When the fixing plate 9 is separated from the inner surface of the support unit 19, the support unit 19 automatically deflects toward the center of the axis of the outer tube body 1 by utilizing the properties of its spring plate material. The dividing grooves 18 divide the support ring 3 into a plurality of support units 19, allowing the liner body 2 to move linearly along the outer tube body 1. When the support ring 3 is pushed by the inner end of the liner body 2, the dividing action of the dividing grooves 18 and the elastic support of the spring 10 ensure that the support ring 3 effectively bends toward the axis.

[0033] The above orientation designations do not represent the specific orientations of the components in this implementation scheme. This implementation scheme is only for the convenience of describing the scheme, and the orientations are described relatively with reference to the figures. In essence, the specific orientations of the components are described based on their actual installation and actual use, as well as the customary orientations of those skilled in the art. This is hereby explained.

[0034] The specific embodiments described above further illustrate the purpose of the present invention, technical solutions, and beneficial effects. It should be understood that the above description is merely a specific embodiment of the present invention and is not intended to limit the scope of protection of the present invention. In particular, it should be noted that for those skilled in the art, any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A high-strength stainless steel seamless pipe, characterized in that: The invention comprises an outer tube body (1) and a liner body (2) arranged in the outer tube body (1), wherein the liner body (2) is symmetrically arranged in the tube cavity of the outer tube body (1) at two upper and lower locations, and the two liner bodies (2) are provided with a support assembly, wherein the support assembly comprises a support ring (3) connected to the opposite ends of the two liner bodies (2), wherein the support ring (3) is made of a spring plate material, wherein the support ring (3) is bent toward the center of the liner body (2), and a shrinkage hole (4) coinciding with the axis of the liner body (2) is provided at the bent end of the support ring (3), and the support assembly also comprises a steel bar (5) connected to the tube cavity wall of the liner body (2), wherein the steel bar (5) is a plurality of steel bars in an annular array and is horizontally extended along the radial direction of the liner body (2) and then connected to the inner wall of the tube cavity of the liner body (2), and a first nut (6) is welded between the opposite ends of the plurality of steel bars (5), and the center of the first nut (6) is aligned with the shrinkage hole (4). ) are on the same axis, the support assembly also includes a screw (7) installed on the first nut (6), the other end of the screw (7) passes through the shrinkage hole (4) and is installed with a fixing plate (9) through a second nut (8), the inner surface of the fixing plate (9) is in contact with the outer end surface of the support ring (3), when the screw (7) rotates and rises, the support ring (3) is dragged by the fixing plate (9) to bend radially toward the axial direction of the liner body (2), and the shrinkage hole (4) is radially contracted; on the contrary, when the screw (7) rotates and descends, the fixing plate (9) is moved away from the support ring (3), and the support ring (3) is radially bent away from the shrinkage hole (4) to restore, and the shrinkage hole (4) is radially expanded, and the outer tube body (1) is also filled with a spring (10), the two ends of the spring (10) extend toward and approach the two liner bodies (2), and the two ends of the spring (10) are elastically supported on the opposite surfaces of the two support rings (3).

2. A high-strength stainless steel seamless pipe according to claim 1, characterized in that: The outer ends of the two screw rods (7) are provided with insertion holes (11), the insertion holes (11) are elliptical holes, and the elliptical hole contour of the insertion holes (11) is provided with rounded corners (12).

3. A high-strength stainless steel seamless pipe according to claim 2, characterized in that: An annular groove (13) is provided on the opposite surfaces of the two support rings (3), and the connecting end of the spring (10) and the support ring (3) contacts in the annular groove (13).

4. A high-strength stainless steel seamless pipe according to claim 3, characterized in that: The diameter of the spring (10) is smaller than the diameter of the lumen of the outer tube body (1), so that a gap (14) is left between the spring (10) and the lumen wall of the outer tube body (1).

5. A high-strength stainless steel seamless pipe according to claim 4, characterized in that: The portion of the support ring (3) connected to the end of the liner body (2) is provided with a first bend (15), the first bend (15) is U-shaped, and the bending direction is away from the cavity wall direction of the outer tube body (1), the end of the first bend (15) is provided with a second bend (16), the second bend (16) is bent toward the cavity wall direction of the outer tube body (1), and the end of the second bend (16) is provided with a third bend (17), the third bend (17) is bent toward the axial direction of the liner body (2).

6. A high-strength stainless steel seamless pipe according to claim 5, characterized in that: The support ring (3) is provided with a circle of dividing grooves (18) in an annular array along the third curved portion (17), one end of the dividing grooves (18) is communicated with the shrinking hole (4), and the other end of the dividing grooves (18) passes through the first curved portion (15) and the second curved portion (16), so that the support ring (3) is divided into a plurality of support units (19), and the dividing grooves (18) gradually narrow toward one end of the shrinking hole (4). When the fixing plate (9) is detached from the inner surface of the support unit (19), the support unit (19) automatically deflects toward the middle direction of the axis of the outer tube body (1) by utilizing the material characteristics of the spring plate.

7. A high-strength stainless steel seamless pipe according to claim 6, characterized in that: The contact surface of the fixing plate (9) with the supporting unit (19) is provided with a tapered surface (20), and the tapered surface (20) gradually inclines toward the edge direction of the fixing plate (9), so that the thickness of the fixing plate (9) gradually becomes thinner toward the edge direction.

8. A high-strength stainless steel seamless pipe according to claim 7, characterized in that: The outer end of one of the liner bodies (2) extends beyond one end of the outer tube body (1), and friction particles (21) are provided on the tube wall of the end where the liner body (2) extends beyond. The outer end of the other liner body (2) extends beyond the other end of the outer tube body (1), and friction particles (21) are also provided on the tube wall of the end where the other liner body (2) extends beyond. The friction particles (21) protrude from the tube wall of the liner body (2).

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