阅读说明：本技术 一种高炉煤气脱硫塔及其密封装置 (Blast furnace gas desulfurizing tower and sealing device thereof ) 是由 刘国华 于 2021-08-31 设计创作，主要内容包括：本发明涉及一种高炉煤气脱硫塔及其密封装置,属于大气净化环保设备领域。该密封装置的第一密封单元包括从上至下依次连接的下料管、旋转球体、球形套、滑动管和压紧管件,内部形成相贯通的下料通道,下料管与承托脱硫剂的底板相连；旋转球体与球形套转动配合,滑动管与套设于其外的密封套管滑动配合而非硬连接；第二密封单元包括入口烟气管、设于入口烟气管上端的环形耳板和套装在入口烟气管上端外周的第二密封绳,入口烟气管上端插入脱硫塔的内环壁面,第二密封绳与内环壁面相贴,入口烟气管与内环壁面轴向滑动密封而非硬连接。通过第一密封单元和第二密封单元的结构设计,消除脱硫塔体轴向变形及底板变形产生的应力集中。(The invention relates to a blast furnace gas desulfurization tower and a sealing device thereof, belonging to the field of environment-friendly equipment for atmosphere purification. The first sealing unit of the sealing device comprises a feeding pipe, a rotary sphere, a spherical sleeve, a sliding pipe and a pressing pipe fitting which are sequentially connected from top to bottom, a feeding channel communicated with each other is formed inside the first sealing unit, and the feeding pipe is connected with a bottom plate for bearing a desulfurizer; the rotary ball body is in running fit with the spherical sleeve, and the sliding pipe is in running fit with the sealing sleeve sleeved outside the sliding pipe instead of being in hard connection with the sealing sleeve; the second sealing unit comprises an inlet flue gas pipe, an annular ear plate arranged at the upper end of the inlet flue gas pipe and a second sealing rope sleeved on the periphery of the upper end of the inlet flue gas pipe, the upper end of the inlet flue gas pipe is inserted into the inner ring wall surface of the desulfurizing tower, the second sealing rope is attached to the inner ring wall surface, and the inlet flue gas pipe and the inner ring wall surface are axially slidably sealed but not rigidly connected. Through the structural design of the first sealing unit and the second sealing unit, the stress concentration generated by axial deformation of the desulfurization tower body and deformation of the bottom plate is eliminated.)

1. The utility model provides a sealing device of blast furnace gas desulfurizing tower which characterized in that: comprises a first sealing unit and a second sealing unit;

the first sealing unit comprises a discharging pipe, a rotary sphere, a spherical sleeve, a sliding pipe and a pressing pipe fitting which are sequentially connected from top to bottom, and a communicated discharging channel is formed inside the first sealing unit; the spherical sleeve is provided with a spherical cavity matched with the rotary sphere, and the rotary sphere is rotatably embedded into the spherical cavity; the lower end of the sliding pipe is inserted into the pressing pipe fitting in a sliding manner; a sealing sleeve is further sleeved on the periphery of the sliding tube, a gap is formed between the sealing sleeve and the sliding tube, and a first sealing rope is arranged in the gap;

the second sealing unit comprises an inlet flue gas pipe, an annular ear plate arranged at the upper end of the inlet flue gas pipe and a second sealing rope sleeved on the periphery of the upper end of the inlet flue gas pipe; the second seals the rope and compresses tightly through fixed stop and gland, and fixed stop locates the sealed rope lower extreme of second and connects on entry flue gas pipe outer wall, and gland locates the sealed rope upper end of second and links to each other with the otic placode.

2. The sealing device of a blast furnace gas desulfurization tower according to claim 1, characterized in that: the rotary ball body is connected with the spherical sleeve through an external flange and a bolt inserted on the two flanges; the rotary ball body is in running fit with the flange thereof, and the spherical sleeve and the flange thereof are integrally constructed.

3. The sealing device of a blast furnace gas desulfurization tower according to claim 1, characterized in that: the upper end that compresses tightly the pipe fitting inserts in the clearance between sealing sleeve and the slip pipe and supports the lower extreme of first sealed rope, and sealing sleeve's inner wall is equipped with and keeps off the shoulder in order to support the upper end of first sealed rope to compress tightly first sealed rope.

4. The sealing device of a blast furnace gas desulfurization tower according to claim 3, characterized in that: the compressing pipe fitting and the sealing sleeve are connected through an integrally-structured peripheral flange and a bolt inserted on the two flanges.

5. The sealing device of a blast furnace gas desulfurization tower according to claim 1, characterized in that: the inlet flue gas pipe and the ear plate are coaxially arranged, and the sealing gland covers are uniformly distributed around the axes of the inlet flue gas pipe and the ear plate.

6. A blast furnace gas desulfurization tower is characterized in that: the sealing device comprises an outer shell, an outer ring wall surface and an inner ring wall surface which are coaxially arranged in the outer shell and divide the inner space of the outer shell into three annular spaces, and the sealing device as claimed in any one of claims 1 to 5;

a desulfurizing agent is filled in an annular space between the outer ring wall surface and the inner ring wall surface, and a bottom plate for bearing a desulfurizing agent is arranged between the lower ends of the outer ring wall surface and the inner ring wall surface; the bottom of the outer shell is inserted with a first sealing unit, wherein the blanking pipe, the rotary sphere and the spherical sleeve extend into the outer shell, the upper end of the blanking pipe is connected with the bottom plate, the sealing sleeve and the pressing pipe piece extend out of the outer shell, and the sealing sleeve is connected with the outer shell;

the bottom of shell body pegs graft the second sealing unit, and wherein, the upper end of entry flue gas pipe, otic placode and sealing gland stretch into the inner ring wall, and the second sealed rope pastes with the inner ring wall mutually.

7. The blast furnace gas desulfurization tower of claim 6, characterized in that: a flue baffle is arranged on the inner ring wall surface at a position corresponding to the desulfurizer filling height, and a flue gas inlet channel is formed by the inlet flue gas pipe, the inner ring wall surface and the flue baffle; a cover plate is arranged between the outer ring wall surface and the inner ring wall surface corresponding to the desulfurizer filling height, a charging pipe is inserted at the top of the outer shell, the lower end of the charging pipe is connected with the cover plate, the upper end of the charging pipe extends out of the outer shell, and the outer ring wall surface, the inner ring wall surface, the cover plate and the bottom plate form a flue gas desulfurization channel; an outlet flue gas pipe is inserted at the top of the outer shell, and the outer ring wall surface, the outer shell and the outlet flue gas pipe form a flue gas outlet channel.

8. The blast furnace gas desulfurization tower of claim 6, characterized in that: the upper ends of the outer ring wall surface and the inner ring wall surface are connected to the inner wall of the outer shell, and a plurality of vent holes are arranged in the areas, exceeding the filling height of the desulfurizer, of the outer ring wall surface and the inner ring wall surface.

9. The blast furnace gas desulfurization tower of claim 6, characterized in that: the inner wall of the outer shell is connected with a limiting stop lever, and the limiting stop lever is arranged corresponding to the lower end of the outer ring wall and is not in contact with the outer ring wall.

10. The blast furnace gas desulfurization tower of claim 6, characterized in that: more than two first sealing units are uniformly distributed around the axle center of the outer shell.

Technical Field

The invention belongs to the field of environment-friendly equipment for atmosphere purification, and relates to a blast furnace gas desulfurization tower and a sealing device thereof.

Background

The blast furnace will produce a large amount of blast furnace gas in the smelting process, about 1400m per 1 ton of iron smelted³～1800m³The blast furnace gas of (1). With the improvement of the domestic environmental protection requirement, environmental protection people gradually recognize that the sulfur content in the flue gas after the blast furnace gas is combusted is higher, and the treatment is urgently needed. But the blast furnace gas is extremely applied to the whole process of steel smeltingWidely, the difficulty of flue gas desulfurization treatment of all furnaces using blast furnace gas is very high. Therefore, many steel enterprises have recently sought a technique for desulfurization of blast furnace gas, i.e., removal of organic sulfur by hydrolysis and conversion to hydrogen sulfide after dust removal of blast furnace gas.

The method adopts conventional dry-method activated carbon to carry out flue gas desulfurization, which is the mainstream process route at present, but the process has severe working condition, the flue gas temperature is stabilized above 150 ℃, the instantaneous temperature can reach above 200 ℃, the internal pressure of the desulfurization equipment is not lower than 0.25MPa, and more factors are required to be considered when the desulfurization equipment is designed: thermal stress concentration due to temperature difference inside the device, deformation due to concentrated load, and the like. The temperature of the annular support plate on the side surface of the desulfurizer in the desulfurizing tower is different from that of the shell of the desulfurizing tower, and the elongation in the axial direction is different; the desulfurizer bottom support deforms under the pressure of hundreds of tons of desulfurizer, and if the blanking pipeline is directly connected to the shell of the desulfurizing tower and the desulfurizer bottom support, stress concentration is caused, a welding line can be torn when the stress concentration is serious, and a similar problem also exists in an inlet flue gas pipeline. Therefore, how to ensure that the flue gas is not exposed and the desulfurizer is not overflowed when the blanking pipe is blanked and the flue gas enters the desulfurizing tower is a problem to be solved urgently.

Disclosure of Invention

In view of the above, the present invention provides a blast furnace gas desulfurization tower and a sealing device thereof, which can solve the problem of stress concentration caused by thermal expansion difference between a feeding pipe and an inlet flue gas pipeline inside the desulfurization tower, and can effectively solve the problem of stress concentration of a welding seam inside equipment in consideration of the uncertainty of deformation of a supporting plate at the bottom of a desulfurizing agent after being stressed.

In order to achieve the purpose, the invention provides the following technical scheme:

a sealing device of a blast furnace gas desulfurization tower comprises a first sealing unit and a second sealing unit;

the first sealing unit comprises a discharging pipe, a rotary sphere, a spherical sleeve, a sliding pipe and a pressing pipe fitting which are sequentially connected from top to bottom, and a communicated discharging channel is formed inside the first sealing unit; the spherical sleeve is provided with a spherical cavity matched with the rotary sphere, and the rotary sphere is rotatably embedded into the spherical cavity; the lower end of the sliding pipe is inserted into the pressing pipe fitting in a sliding manner; a sealing sleeve is further sleeved on the periphery of the sliding tube, a gap is formed between the sealing sleeve and the sliding tube, and a first sealing rope is arranged in the gap;

the second sealing unit comprises an inlet flue gas pipe, an annular ear plate arranged at the upper end of the inlet flue gas pipe and a second sealing rope sleeved on the periphery of the upper end of the inlet flue gas pipe; the second seals the rope and compresses tightly through fixed stop and gland, and fixed stop locates the sealed rope lower extreme of second and connects on entry flue gas pipe outer wall, and gland locates the sealed rope upper end of second and links to each other with the otic placode.

Further, the rotary sphere and the spherical sleeve are connected through a peripheral flange and a bolt inserted on the two flanges; the rotary ball body is in running fit with the flange thereof, and the spherical sleeve and the flange thereof are integrally constructed.

Furthermore, the upper end that compresses tightly the pipe fitting inserts in the clearance between seal sleeve and the slip pipe and supports the lower extreme of first sealed rope, and seal sleeve's inner wall is equipped with and keeps off the shoulder in order to support the upper end of first sealed rope to compress tightly first sealed rope.

Furthermore, the pressing pipe fitting and the sealing sleeve are connected through an integrally-constructed peripheral flange and a bolt inserted on the two flanges.

Further, the inlet flue gas pipe and the ear plate are coaxially arranged, and the sealing gland covers are uniformly distributed around the axle centers of the inlet flue gas pipe and the ear plate.

A blast furnace gas desulfurization tower comprises an outer shell, an outer ring wall surface and an inner ring wall surface which are coaxially arranged in the outer shell and divide the space in the outer shell into three annular spaces, and the sealing device;

a desulfurizing agent is filled in an annular space between the outer ring wall surface and the inner ring wall surface, and a bottom plate for bearing a desulfurizing agent is arranged between the lower ends of the outer ring wall surface and the inner ring wall surface; the bottom of the outer shell is inserted with a first sealing unit, wherein the blanking pipe, the rotary sphere and the spherical sleeve extend into the outer shell, the upper end of the blanking pipe is connected with the bottom plate, the sealing sleeve and the pressing pipe piece extend out of the outer shell, and the sealing sleeve is connected with the outer shell;

the bottom of shell body pegs graft the second sealing unit, and wherein, the upper end of entry flue gas pipe, otic placode and sealing gland stretch into the inner ring wall, and the second sealed rope pastes with the inner ring wall mutually.

Further, a flue baffle is arranged on the inner ring wall surface at a position corresponding to the desulfurizer filling height, and a flue gas inlet channel is formed by the inlet flue gas pipe, the inner ring wall surface and the flue baffle; a cover plate is arranged between the outer ring wall surface and the inner ring wall surface corresponding to the desulfurizer filling height, a charging pipe is inserted at the top of the outer shell, the lower end of the charging pipe is connected with the cover plate, the upper end of the charging pipe extends out of the outer shell, and the outer ring wall surface, the inner ring wall surface, the cover plate and the bottom plate form a flue gas desulfurization channel; an outlet flue gas pipe is inserted at the top of the outer shell, and the outer ring wall surface, the outer shell and the outlet flue gas pipe form a flue gas outlet channel.

Furthermore, the upper ends of the outer ring wall surface and the inner ring wall surface are connected to the inner wall of the outer shell, and a plurality of vent holes are formed in the areas, exceeding the filling height of the desulfurizer, of the outer ring wall surface and the inner ring wall surface.

Furthermore, the inner wall of the outer shell is connected with a limiting stop lever, and the limiting stop lever is arranged corresponding to the lower end of the outer ring wall and is not in contact with the outer ring wall.

Furthermore, the first sealing unit has more than two around the axle center equipartition of shell body.

The invention has the beneficial effects that:

because the axial length of the tower body of the blast furnace gas desulfurization tower is large, and the outer shell, the outer ring wall surface and the inner ring wall surface can form temperature difference in the flue gas treatment process, the expansion amount in the axial direction is also obviously different. If the blanking pipe is directly connected with the bottom plate and the outer shell, the difference of the expansion amounts of dozens of millimeters is enough to tear the connecting welding seam, so that the sliding pipe, the sealing sleeve, the inlet flue gas pipe and the wall surface of the inner ring need to adopt an axial sliding sealing structure instead of hard connection in the axial direction.

In order to ensure that the blanking pipe can slide in the axial direction, the blanking pipe needs to be coaxially positioned with the sealing sleeve; meanwhile, the bottom plate bears hundreds of tons of desulfurizer, the bottom plate can deform, the deformation direction is uncertain, and the stress concentration at the blanking pipe and the bottom plate can be realized if the blanking pipe is directly connected due to the coaxial positioning and sealing of the bottom plate. In order to avoid the above situation, the rotary ball body is connected with the spherical sleeve in a rotating way, which is equivalent to form a universal joint at the position, so that the blanking pipe and the sliding pipe can slide in the axial direction, and even if the blanking pipe deforms and is not coaxial with the sliding pipe, the stress concentration can be eliminated through the rotary matching of the rotary ball body and the spherical sleeve.

Additional advantages, objects, and features of the invention will be set forth in part in the description which follows and in part will become apparent to those having ordinary skill in the art upon examination of the following or may be learned from practice of the invention. The objectives and other advantages of the invention may be realized and attained by the means of the instrumentalities and combinations particularly pointed out hereinafter.

Drawings

For the purposes of promoting a better understanding of the objects, aspects and advantages of the invention, reference will now be made to the following detailed description taken in conjunction with the accompanying drawings in which:

FIG. 1 is an overall cross-sectional view of a blast furnace gas desulfurization tower of the present invention;

FIG. 2 is an enlarged view I of a portion of FIG. 1;

FIG. 3 is a partial enlarged view II of FIG. 1;

FIG. 4 is an enlarged view III of a portion of FIG. 1;

FIG. 5 is an enlarged partial view IV of FIG. 1;

FIG. 6 is a view taken along line A of FIG. 1;

fig. 7 is a view from direction B of fig. 1.

Reference numerals: the device comprises an inlet flue gas pipe 1, an outlet flue gas pipe 2, an outer shell 3, an outer ring wall surface 4, an inner ring wall surface 5, a vent hole 5.1, a flue baffle 6, a charging pipe 7, a desulfurizer 8, a limiting stop lever 9, a blanking pipe 10, a rotary sphere 11, a flange 12, a spherical sleeve 13, a bolt 14, a sliding pipe 15, a sealing sleeve 16, a first sealing rope 17, a pressing pipe 18, a fixed baffle 19, a second sealing rope 20, an ear plate 21, a sealing gland 22, a bottom plate 23 and a cover plate 24.

Detailed Description

The embodiments of the present invention are described below with reference to specific embodiments, and other advantages and effects of the present invention will be easily understood by those skilled in the art from the disclosure of the present specification. The invention is capable of other and different embodiments and of being practiced or of being carried out in various ways, and its several details are capable of modification in various respects, all without departing from the spirit and scope of the present invention. It should be noted that the drawings provided in the following embodiments are only for illustrating the basic idea of the present invention in a schematic way, and the features in the following embodiments and examples may be combined with each other without conflict.

Wherein the showings are for the purpose of illustrating the invention only and not for the purpose of limiting the same, and in which there is shown by way of illustration only and not in the drawings in which there is no intention to limit the invention thereto; to better illustrate the embodiments of the present invention, some parts of the drawings may be omitted, enlarged or reduced, and do not represent the size of an actual product; it will be understood by those skilled in the art that certain well-known structures in the drawings and descriptions thereof may be omitted.

The same or similar reference numerals in the drawings of the embodiments of the present invention correspond to the same or similar components; in the description of the present invention, it should be understood that if there is an orientation or positional relationship indicated by terms such as "upper", "lower", "left", "right", "front", "rear", etc., based on the orientation or positional relationship shown in the drawings, it is only for convenience of description and simplification of description, but it is not an indication or suggestion that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated, and therefore, the terms describing the positional relationship in the drawings are only used for illustrative purposes, and are not to be construed as limiting the present invention, and the specific meaning of the terms may be understood by those skilled in the art according to specific situations.

Referring to fig. 1 to 7, the present embodiment provides a blast furnace gas desulfurization tower and a sealing device thereof.

The sealing device includes a first sealing unit and a second sealing unit.

The first sealing unit comprises a blanking pipe 10, a rotary sphere 11, a spherical sleeve 13, a sliding pipe 15 and a pressing pipe fitting 18 which are sequentially connected from top to bottom, and a through blanking channel is formed inside the first sealing unit; the spherical sleeve 13 is provided with a spherical cavity matched with the rotary sphere 11, and the rotary sphere 11 is rotatably embedded into the spherical cavity; the lower end of the sliding pipe 15 is inserted into the pressing pipe 18 in a sliding manner; the periphery of the sliding tube 15 is also sleeved with a sealing sleeve 16, a gap exists between the sealing sleeve 16 and the sliding tube 15, and a first sealing rope 17 is arranged in the gap. The upper end of the pressing pipe member 18 is inserted into the gap between the sealing sleeve 16 and the sliding pipe 15 and abuts against the lower end of the first sealing rope 17, and the inner wall of the sealing sleeve 16 is provided with a shoulder to abut against the upper end of the first sealing rope 17, thereby pressing the first sealing rope 17. The pressure pipe 18 and the sealing sleeve 16 are connected by an integrally formed peripheral flange and bolts inserted into the two flanges.

The rotary ball body 11 is connected with the spherical sleeve 13 through a peripheral flange and a bolt 14 inserted on the two flanges; the rotary sphere 11 is in running fit with its flange 12, with which the spherical sleeve 13 is constructed in one piece.

The second sealing unit comprises an inlet flue gas pipe 1, an annular ear plate 21 arranged at the upper end of the inlet flue gas pipe 1 and a second sealing rope 20 sleeved on the periphery of the upper end of the inlet flue gas pipe 1; the second sealed rope 20 compresses tightly through fixed stop 19 and gland 22, and fixed stop 19 locates the second sealed rope 20 lower extreme and connects on entry flue gas pipe 1 outer wall, and gland 22 locates the second sealed rope 20 upper end and links to each other with otic placode 21. The inlet flue gas pipe 1 and the ear plate 21 are arranged coaxially, and the sealing glands 22 are evenly distributed around the axes of the two.

The desulfurizing tower comprises an outer shell 3, an outer ring wall surface 4 and an inner ring wall surface 5 which are coaxially arranged in the outer shell 3 and divide the space in the outer shell 3 into three annular spaces, and the sealing device.

Specifically, the annular space between the outer ring wall surface 4 and the inner ring wall surface 5 is filled with a desulfurizing agent 8, a bottom plate 23 used for bearing the desulfurizing agent 8 is arranged between the lower ends of the outer ring wall surface 4 and the inner ring wall surface 5, a cover plate 24 is arranged between the outer ring wall surface 4 and the inner ring wall surface 5 corresponding to the filling height of the desulfurizing agent 8, a feed pipe 7 which is uniform around the axis of the outer shell 3 is inserted into the top of the outer shell 3, the lower end of the feed pipe 7 is connected with the cover plate 24, the upper end of the feed pipe extends out of the outer shell 3, and the outer ring wall surface 4, the inner ring wall surface 5, the cover plate 24 and the bottom plate 23 form a flue gas desulfurization channel. The cover plate 24 is close to the outer shell 3, and the expansion amount in the axial direction is not large, so that the manner of hard connection of the feed pipe 7 is adopted here.

The bottom of shell body 3 is pegged graft first sealing unit, and wherein, unloading pipe 10, rotary sphere 11 and spherical cover 13 stretch into in the shell body 3, and unloading pipe 10 upper end links to each other with bottom plate 23, and seal sleeve 16 and compress tightly pipe fitting 18 and stretch out outside shell body 3, and seal sleeve 16 links to each other with shell body 3. More than two first sealing units are uniformly distributed around the axle center of the outer shell 3.

The bottom of the outer shell 3 is inserted with a second sealing unit, wherein the upper end of the inlet flue gas pipe 1, the ear plate 21 and the sealing gland 22 extend into the inner ring wall surface 5, the second sealing rope 20 is attached to the inner ring wall surface 5, and the inlet flue gas pipe 1, the ear plate 21 and the inner ring wall surface 5 are coaxially arranged. A flue baffle 6 is arranged on the inner ring wall surface 5 corresponding to the filling height of the desulfurizer 8, and the inlet flue gas pipe 1, the inner ring wall surface 5 and the flue baffle 6 form a flue gas inlet channel. The inlet flue pipe 1 prevents rocking of the inner ring wall 5.

An outlet flue gas pipe 2 is inserted into the top of the outer shell 3, and a flue gas outlet channel is formed by the outer ring wall surface 4, the outer shell 3 and the outlet flue gas pipe 2. The upper ends of the outer ring wall surface 4 and the inner ring wall surface 5 are connected to the inner wall of the outer shell 3, and a plurality of vent holes 5.1 are arranged in the areas of the outer ring wall surface 4 and the inner ring wall surface 5, which exceed the filling height of the desulfurizing agent 8, so as to ensure the penetration of a flue gas outlet channel.

The inner wall of the outer shell 3 is connected with limit stop levers 9 which are uniformly distributed around the axis of the outer shell 3, and the limit stop levers 9 are arranged corresponding to the lower end of the outer ring wall surface 4 and are not contacted with the outer ring wall surface 4. The limit stop prevents the outer ring wall surface 4 from swinging.

The design temperature of the blast furnace gas desulfurization tower is not higher than 250 ℃, and the working temperature is generally 150 ℃. Because the axial length of the tower body is large, and the outer shell 3, the outer ring wall surface 4 and the inner ring wall surface 5 can form temperature difference in the flue gas treatment process, the expansion amount in the axial direction is also obviously different. If the blanking pipe 10 is directly connected with the bottom plate 23 and the outer shell 3, the difference of the expansion amounts of dozens of millimeters is enough to tear the connecting weld seam, so that the sliding pipe 15, the sealing sleeve 16, the inlet flue gas pipe 1 and the inner ring wall surface 5 need to adopt an axial sliding sealing structure instead of hard connection in the axial direction.

In order to ensure that the blanking pipe 10 can slide in the axial direction, the blanking pipe 10 needs to be coaxially positioned with the sealing sleeve 16; meanwhile, considering that the bottom plate 23 bears hundreds of tons of desulfurizer 8, the bottom plate 23 can deform and the deformation direction is uncertain, and because the bottom plate 23 is coaxially positioned and sealed, if the blanking pipe 10 is directly connected, the stress concentration can be realized at the positions of the blanking pipe 10 and the bottom plate 23. In order to avoid the above situation, the rotating ball 11 is connected with the spherical sleeve 13 in a rotating way, namely a universal joint is formed at the position, so that the blanking pipe 10 and the sliding pipe 15 can slide in the axial direction, and even if the blanking pipe 10 deforms and is not coaxial with the sliding pipe 15, the stress concentration can be eliminated through the rotating matching of the rotating ball 11 and the spherical sleeve 13.

Finally, the above embodiments are only intended to illustrate the technical solutions of the present invention and not to limit the present invention, and although the present invention has been described in detail with reference to the preferred embodiments, it will be understood by those skilled in the art that modifications or equivalent substitutions may be made on the technical solutions of the present invention without departing from the spirit and scope of the technical solutions, and all of them should be covered by the claims of the present invention.