Inter-tube expander

Abstract

The utility model belongs to the technical field of pipeline installation, and discloses an inter-pipe expander which comprises a telescopic structure, an abutting structure and an injection structure. The telescopic structure comprises a cylinder body, a first piston rod and a second piston rod, a fixed cavity is defined by the cylinder body, the fixed cavity is divided into a first cavity and a second cavity by the partition part, the first end of the first piston rod is slidably arranged in the first cavity, and the first end of the second piston rod is slidably arranged in the second cavity. The cylinder body is provided with a first hole, a second hole and a third hole, the first cavity is communicated with the first hole and the second hole, and the second cavity is communicated with the first hole and the third hole. The abutting mechanism comprises two abutting assemblies, and the two abutting assemblies are arranged at the ends, away from each other, of the first piston rod and the second piston rod correspondingly. The injection structure injects media into the first cavity and the second cavity to drive the first piston rod and the second piston rod to be away from each other so as to enlarge the distance between the first pipeline and the second pipeline, the structure is compact, the working stroke is large, and the device can be suitable for various scenes.

Description

TECHNICAL FIELD

[0001] The utility model relates to pipeline installation technical field especially relates to an inter -tube expander. BACKGROUND

[0002] Ultrasonic flowmeter and flame arrester are the equipment components commonly used on oil and gas pipeline station process pipeline, and need to be periodically disassembled and sent for inspection or maintenance according to relevant provisions. However, long-distance pipeline is prone to length change due to stress phenomenon or temperature, which causes ultrasonic flowmeter and flame arrester to be unable to be normally disassembled.

[0003] The inter -tube expander in prior art is partly made of high-precision or special material, and the manufacturing cost is high, so that the overall investment cost of the pipeline system is high. The other part has the disadvantage that the spacing expansion stroke is small, and is greatly limited by the application site conditions and tooling, and cannot be applied to various scenes. UTILITY MODEL CONTENT

[0004] The utility model discloses a kind of inter -tube expanders, compact structure, installation and maintenance are convenient, manufacturing cost is low, working stroke is larger, can be applied to various scenes.

[0005] To achieve this purpose, the utility model adopts the following technical solutions:

[0006] Provide a kind of inter -tube expander, comprising:

[0007] Telescopic structure, including cylinder, first piston rod and second piston rod, the cylinder is surrounded with fixed chamber, the fixed chamber is provided with partition, the partition separates the fixed chamber into first chamber and second chamber, the first piston rod first end is slidably arranged in the first chamber, and the second piston rod first end is slidably arranged in the second chamber;The cylinder is provided with first hole, second hole and third hole, the first chamber is communicated at the first hole and the second hole, and the second chamber is communicated at the first hole and the third hole;

[0008] The telescopic structure has the expansion state that the first piston rod and the second piston rod are away from each other and the retraction state that the first piston rod and the second piston rod are close to each other;

[0009] Butt joint structure, including two butt joint components, one of the butt joint components is arranged at the second end of the first piston rod, and the other butt joint component is arranged at the second end of the second piston rod;

[0010] Injection structure, when the expansion state, the first hole is communicated at the output end of the injection structure;When the retraction state, the second hole and the third hole are all communicated at the output end of the injection structure.

[0011] As an alternative to the inter-tube expander, the partition is provided with a third chamber, and the first hole is in communication with the third chamber.

[0012] The two side walls of the partition are respectively provided with a fourth hole and a fifth hole, the fourth hole is in communication with the first chamber, and the fifth hole is in communication with the second chamber.

[0013] As an alternative to the inter-tube expander, the outer wall of the cylinder is provided with a first pipeline and a second pipeline, the first pipeline is in communication with the second hole, and the second pipeline is in communication with the third hole.

[0014] As an alternative to the inter-tube expander, a check valve is arranged on each of the first pipeline and the second pipeline.

[0015] As an alternative to the inter-tube expander, the cylinder includes a cylinder barrel and two cylinder covers, and the two cylinder covers are arranged at the two ends of the cylinder barrel respectively to enclose the fixed chamber.

[0016] The first piston rod and the second piston rod are arranged to slide through the corresponding cylinder cover.

[0017] As an alternative to the inter-tube expander, a sealing member is arranged between the first piston rod and the corresponding cylinder cover, and / or a sealing member is arranged between the second piston rod and the corresponding cylinder cover.

[0018] As an alternative to the inter-tube expander, the injection structure includes an injection mechanism and an injection pipeline, and the inlet of the injection pipeline is in communication with the output end of the injection mechanism.

[0019] In the expanded state, the first hole is in communication with the outlet of the injection pipeline.

[0020] In the retracted state, the second hole and the third hole are both in communication with the outlet of the injection pipeline.

[0021] A pressure monitor is arranged on the injection pipeline, and the pressure monitor is used to monitor the pressure of the medium in the injection pipeline.

[0022] As an alternative to the inter-tube expander, the inter-tube expander further includes a support structure, the support structure is arranged on a support base, and the cylinder is arranged on the support structure in a vertically liftable manner.

[0023] As an alternative to the inter-tube expander, the outer wall of the cylinder is provided with a first joint, and the first joint is in communication with the first hole.

[0024] As an alternative to the tube expander, the abutment assembly includes a fixed plate and a buffer, the fixed plate is arranged at the second end of the first piston rod or the second end of the second piston rod, and the buffer is arranged on the side of the fixed plate facing the pipeline.

[0025] The utility model discloses the beneficial effects of:

[0026] The utility model provides a tube expander, needs to increase the interval between first pipeline and second pipeline, first hole is communicated in the output end of injection structure, and the medium that injection structure output end flows out, part enters first chamber, and another part enters second chamber, under the impetus of medium, drives the first end of first piston rod and the first end of second piston rod away from each other to increase the tube distance between first pipeline and second pipeline. When needing to reduce the interval between first pipeline and second pipeline, second hole and third hole are all communicated in the output end of injection structure, and the medium that injection structure output end flows out, part enters first chamber through second hole, and the first piston rod is moved along the direction of approaching the separator, and the medium between the separator and the first end of first piston rod simultaneously is discharged first chamber through first hole, another part enters second chamber through third hole, and the second piston rod is moved along the direction of approaching the separator, and the medium between the separator and the first end of second piston rod simultaneously is discharged second chamber through first hole, realize the mutual approach of the first end of first piston rod and the first end of second piston rod, to reduce the interval between first pipeline and second pipeline. The expander is compact, and installation and maintenance are convenient, and the manufacturing cost is low, and simultaneously, the working stroke is larger, and can be applicable to a variety of scenes. BRIEF DESCRIPTION OF DRAWINGS

[0027] Figure 1 It is the front view of the tube expander provided by the embodiment of the utility model specific implementation mode;

[0028] Figure 2 It is the side view of the tube expander provided by the embodiment of the utility model specific implementation mode;

[0029] Figure 3 It is the top view of the tube expander provided by the embodiment of the utility model specific implementation mode;

[0030] Figure 4 It is the section view of telescopic structure and abutment structure provided by the embodiment of the utility model specific implementation mode.

[0031] In the drawing:

[0032] 1, telescopic structure;

[0033] 11, cylinder; 111, first hole; 112, second hole; 113, third hole; 114, first pipeline; 115, second pipeline; 116, cylinder barrel; 117, cylinder cover; 118, first joint; 119, second joint;

[0034] 12, first piston rod; 13, second piston rod;

[0035] 14, partition; 140, third chamber; 15, sealing member;

[0036] 2, abutting structure; 21, abutting assembly; 211, fixed plate; 212, buffer member;

[0037] 3, support structure; 31, support seat; 32, threaded rod; 33, operation part; 34, supporting member. DETAILED DESCRIPTION

[0038] The utility model will be described in further detail below in combination with the drawings and embodiments. It can be understood that the specific embodiments described herein are only used to explain the utility model, and not to limit the utility model. In addition, it should be noted that, in order to facilitate the description, only the part related to the utility model is shown in the drawings, not all structures.

[0039] In the description of the utility model, unless otherwise explicitly specified and limited, the terms "connected", "connected", "fixed" should be understood broadly, for example, it can be fixedly connected, or it can be detachably connected, or it can be integrated, it can be mechanically connected, or it can be electrically connected, it can be directly connected, or it can be indirectly connected through an intermediate medium, it can be the internal communication of two elements or the interaction relationship of two elements. For ordinary skilled in the art, the specific meaning of the above terms in the utility model can be understood according to the specific circumstances.

[0040] In the utility model, unless otherwise explicitly specified and limited, the first feature "on" or "below" the second feature can include that the first and second features are in direct contact, or the first and second features are not in direct contact but are in contact through another feature between them. Moreover, the first feature "on", "above" and "on" the second feature includes that the first feature is directly above and obliquely above the second feature, or only indicates that the horizontal height of the first feature is higher than that of the second feature. The first feature "below", "below" and "below" the second feature includes that the first feature is directly below and obliquely below the second feature, or only indicates that the horizontal height of the first feature is less than that of the second feature.

[0041] In the description of this embodiment, the terms "upper," "lower," "right," etc., refer to the orientation or positional relationship shown in the accompanying drawings. They are used only for ease of description and simplification of operation, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this utility model. In addition, the terms "first" and "second" are only used for distinction in description and have no special meaning.

[0042] The technical solution of this utility model will be further described below with reference to the accompanying drawings and specific embodiments.

[0043] like Figures 1 to 4 As shown, this embodiment provides a pipe expander, including a telescopic structure 1, an abutment structure 2, and an injection structure (not shown in the figure). The telescopic structure 1 includes a cylinder 11, a first piston rod 12, and a second piston rod 13. The cylinder 11 surrounds a fixed chamber, and a partition 14 is provided in the fixed chamber, dividing the fixed chamber into a first chamber and a second chamber. The first end of the first piston rod 12 is slidably disposed in the first chamber, and the first end of the second piston rod 13 is slidably disposed in the second chamber. The cylinder 11 is provided with a first hole 111, a second hole 112, and a third hole 113. The first chamber communicates with the first hole 111 and the second hole 112, and the second chamber communicates with the first hole 111 and the third hole 113. The abutment mechanism includes two abutment components 21. One abutment component 21 is disposed at the second end of the first piston rod 12 and is configured to abut against the first pipe; the other abutment component 21 is disposed at the second end of the second piston rod 13 and is configured to abut against the second pipe.

[0044] The telescopic structure 1 has an expanded state in which the first piston rod 12 and the second piston rod 13 are away from each other, and a retracted state in which the first piston rod 12 and the second piston rod 13 are close to each other. In the expanded state, the first hole 111 is communicated with the output end of the injection structure, and the medium flowing out of the output end of the injection structure enters the first chamber and the second chamber, and under the pushing of the medium, the first end of the first piston rod 12 and the first end of the second piston rod 13 are away from each other to increase the distance between the first pipe and the second pipe. In the retracted state, the second hole 112 and the third hole 113 are both communicated with the output end of the injection structure, and the medium flowing out of the output end of the injection structure enters the first chamber through the second hole 112 and pushes the first piston rod 12 to move along the direction of approaching the partition 14, and at the same time, the medium between the partition 14 and the first end of the first piston rod 12 is discharged from the first chamber through the first hole 111; the other part enters the second chamber through the third hole 113, pushes the second piston rod 13 to move along the direction of approaching the partition 14, and at the same time, the medium between the partition 14 and the first end of the second piston rod 13 is discharged from the second chamber through the first hole 111, so as to realize the mutual approach of the first end of the first piston rod 12 and the first end of the second piston rod 13, and complete the retraction of the telescopic structure 1. The expander structure is compact, easy to install and maintain, and low in manufacturing cost, and at the same time, has a large working stroke and can be applied to various scenes.

[0045] Specifically, in the embodiment, only one injection structure is provided, and when the switching between the expanded state and the retracted state is needed, the injection structure can be disassembled to realize the communication of the injection structure with the first hole 111 or the communication of the injection structure with the second hole 112 and the third hole 113; or the injection structure itself is provided with a reversing valve, and the output end of the injection structure is always communicated with the first hole 111, the second hole 112 and the third hole 113, and by adjusting the reversing valve, the flow direction of the medium at the output end of the injection structure can be freely selected. In the expanded state, the medium flowing out of the output end of the injection structure flows to the first hole 111; in the retracted state, the medium flowing out of the output end of the injection structure flows to the second hole 112 and the third hole 113 respectively. Specifically, the reversing valve is a prior art device in the field, and its specific structure and principle are referred to the prior art, which will not be described here.

[0046] Specifically, the first piston rod 12 includes a first rod body and a first piston arranged at the end of the first rod body, the first piston abuts the inner wall of the first chamber in the circumferential direction, and the diameter of the first rod body is smaller than the diameter of the first piston; the second piston rod 13 includes a second rod body and a second piston arranged at the end of the second rod body, the second piston abuts the inner wall of the second chamber in the circumferential direction, and the diameter of the second rod body is smaller than the diameter of the second piston. In the expanded state, the medium pushes the end of the first piston facing the partition 14 and the end of the second piston facing the partition 14 respectively; in the retracted state, the medium pushes the end of the first piston away from the partition 14 and the end of the second piston away from the partition 14 respectively.

[0047] Exemplarily, in the embodiment, the medium output by the injection structure output end is oil.

[0048] Optionally, referring to Figure 4 , the cylinder body 11 comprises a cylinder barrel 116 and two cylinder covers 117, which are arranged at two ends of the cylinder barrel 116 respectively to enclose a fixed chamber. The first piston rod 12 and the second piston rod 13 are both arranged to slide through the corresponding cylinder cover 117. The above arrangement makes the overall structure of the cylinder body 11 stable and convenient to maintain.

[0049] Further, a sealing member 15 is arranged between the first piston rod 12 and the corresponding cylinder cover 117, and / or a sealing member 15 is arranged between the second piston rod 13 and the corresponding cylinder cover 117. The above arrangement of the sealing member 15 can play a buffering role in the sliding process of the first piston rod 12 and the second piston rod 13, so that the first piston rod 12 and the second piston rod 13 can move at a uniform speed and uniform distribution. At the same time, when the first piston rod 12 and the second piston rod 13 move to the maximum stroke, the first end of the first piston rod 12 and / or the first end of the second piston rod 13 will interfere with the corresponding cylinder cover 117, forcing the first piston rod 12 and / or the second piston rod 13 to slide, thereby avoiding the first piston rod 12 and / or the second piston rod 13 from sliding off. Specifically, in the embodiment, the sealing member 15 is arranged between the first piston rod 12 and the corresponding cylinder cover 117 and between the second piston rod 13 and the corresponding cylinder cover 117.

[0050] Specifically, in the embodiment, the sealing member 15 comprises a sealing ring and a retaining ring. The sealing ring is used to seal the gap between the piston rod and the cylinder cover 117 to prevent leakage of the medium, and at the same time can also block external dust and impurities from entering the chamber to ensure the sealing effect. The retaining ring is used to protect the sealing ring and limit the movement of the sealing ring. The sealing ring and the retaining ring work together to significantly improve the reliability and service life of the telescopic structure 1.

[0051] More specifically, a dust cover is arranged between the first piston rod 12 and the corresponding cylinder cover 117 and between the second piston rod 13 and the corresponding cylinder cover 117 to effectively block external dust and ensure normal use of the telescopic structure 1.

[0052] Optionally, as Figure 3 shown, the outer wall of the cylinder body 11 is provided with a first joint 118 which is communicated with the first hole 111. The above arrangement can facilitate the communication between the first hole 111 and the injection structure and improve the work efficiency. Specifically, the first joint 118 is a thread joint, a sleeve joint or the like commonly used in the art.

[0053] Optionally, the outer wall of the cylinder 11 is provided with a first pipeline 114 and a second pipeline 115, the first pipeline 114 is communicated with the second hole 112, and the second pipeline 115 is communicated with the third hole 113. The above-mentioned arrangement can facilitate the injection structure to inject the medium into the first chamber and the second chamber.

[0054] Specifically, in the embodiment, the end of the first pipeline 114 away from the second hole 112 and the end of the second pipeline 115 away from the third hole 113 are respectively connected to the two ends of the second joint 119, that is, the first pipeline 114 and the second pipeline 115 are communicated with each other, the oil injection structure is directly communicated with the second joint 119, and the medium can be output to the first pipeline 114 and the second pipeline 115 at the same time, so that the pipeline arrangement is simplified and the space layout is optimized. Exemplarily, the second joint 119 is a tee joint commonly used in the art.

[0055] Further, the first pipeline 114 and the second pipeline 115 are both provided with check valves. During the sliding of the first piston rod 12 and the second piston rod 13, if the moving strokes of the first piston rod 12 and the second piston rod 13 are inconsistent, the flow rate in the first pipeline 114 and the flow rate in the second pipeline 115 can be adjusted by the check valves to respectively adjust the pressure of the first chamber and the pressure of the second chamber, and thus the uniform force on the first pipeline 114 and the second pipeline 115 is ensured. Specifically, the check valve is an existing device disclosed in the prior art, and the specific structure and principle thereof are referred to the prior art, which will not be described here.

[0056] Optionally, as shown in Figure 4 The partition 14 surrounds a third chamber 140, and the first hole 111 is communicated with the third chamber 140; the two side walls of the partition 14 are respectively provided with a fourth hole and a fifth hole, the fourth hole is communicated with the first chamber, and the fifth hole is communicated with the second chamber. That is to say, the partition 14 is a hollow structure. In the expanded state, the medium flowing out of the output end of the injection structure all flows into the third chamber 140, and then is divided into two parts, one part flows into the first chamber to push the first piston rod 12 to slide, and the other part flows into the second chamber to push the second piston rod 13 to slide. In the retracted state, the medium between the partition 14 and the first end of the first piston rod 12 enters the third chamber 140 through the fourth hole, the medium between the partition 14 and the first end of the second piston rod 13 enters the third chamber 140 through the fifth hole, and then flows out of the third chamber 140 through the first hole 111. The above-mentioned arrangement can buffer a part of the medium in the third chamber 140 by the partition 14, optimize the space layout inside the cylinder 11, and make the structure more compact and reasonable.

[0057] Specifically, the fourth hole and the fifth hole are both provided with a plurality of holes to increase the flow rate of the medium, improve the expansion and retraction speed of the telescopic structure 1, and ensure the work efficiency; the number of the fourth hole and the fifth hole can be set as required, which will not be specifically limited here.

[0058] Optionally, continuing to refer to Figure 4 , the abutting assembly 21 comprises a fixed plate 211 and a buffer 212, the fixed plate 211 is arranged on the second end of the first piston rod 12 or the second end of the second piston rod 13; the buffer 212 is arranged on the side of the fixed plate 211 facing the pipeline, and the pipeline abuts against the buffer 212 to avoid damage to the pipeline due to abrasion. Specifically, in this embodiment, the buffer 212 is a nylon plate and is fixed on the fixed plate 211 by bolts.

[0059] Optionally, the injection structure comprises an injection mechanism and an injection pipeline, the inlet of the injection pipeline is communicated with the outlet of the injection mechanism. In the expanded state, the first hole 111 is communicated with the outlet of the injection pipeline, and specifically in this embodiment, the first joint 118 is communicated with the outlet of the injection pipeline, so that the medium at the outlet of the injection pipeline flows through the first joint 118, the first hole 111, the third chamber 140 in sequence, and is then divided into the first chamber and the second chamber; in the retracted state, the second hole 112 and the third hole 113 are both communicated with the outlet of the injection pipeline, and specifically in this embodiment, the inlet of the second joint 119 is communicated with the outlet of the injection pipeline, so that the medium at the outlet of the injection pipeline is divided into the first pipeline 114 and the second pipeline 115 through the second joint 119. A pressure detector is arranged on the injection pipeline, and the pressure detector is used to monitor the pressure of the medium in the injection pipeline to prevent the pressure from being too high and ensure the safety of the operation. Specifically, the pressure detector is a device disclosed in the prior art, and its specific structure and principle are referred to the prior art, which will not be described here.

[0060] Optionally, the inter-pipe expander further comprises a support structure 3, the support structure 3 is arranged on a support base, and the cylinder body 11 is vertically and liftably arranged on the support structure 3, so as to be applicable to first pipelines and second pipelines of different heights, thereby improving the applicability of the inter-pipe expander.

[0061] Specifically, as shown in Figure 1 and Figure 2 , the support structure 3 comprises a support seat 31 and a threaded rod 32, the support seat 31 abuts against the support base, and an adjusting cavity extending in the vertical direction is formed in the support seat 31, the inner wall of the adjusting cavity is provided with threads, the threaded rod 32 is vertically and positionally adjustably arranged in the adjusting cavity, and the cylinder body 11 is arranged at the upper end of the threaded rod 32. By rotating the threaded rod 32, the cylinder body 11 can be lifted in the vertical direction. The above-mentioned support base is the ground or a stable load-bearing platform.

[0062] More specifically, the support structure 3 further comprises an operating part 33, a gear transmission assembly is arranged between the operating part 33 and the threaded rod 32, and rotating the operating part 33 can drive the threaded rod 32 to lift or lower, which is simple and convenient to operate. The gear transmission assembly is a structure known in the art, and its specific structure and principle will not be described here.

[0063] Optionally, continuing to refer to Figure 1 The upper end of the threaded rod 32 is provided with a supporting piece 34 for supporting the cylinder body 11 to ensure the stability of the cylinder body 11.

[0064] Obviously, the above embodiments of the present application are merely examples for clearly illustrating the present application, and are not intended to limit the implementation modes of the present application. For those skilled in the art, various obvious changes, re-adjustments and substitutions can be made without departing from the protection scope of the present application. Here, it is unnecessary and impossible to enumerate all the implementation modes. Any modification, equivalent substitution and improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application claim.

Claims

1. A tube expander, characterized in that, include: The telescopic structure (1) includes a cylinder (11), a first piston rod (12), and a second piston rod (13). The cylinder (11) surrounds a fixed chamber, and a partition (14) is provided in the fixed chamber. The partition (14) divides the fixed chamber into a first chamber and a second chamber. The first end of the first piston rod (12) is slidably disposed in the first chamber, and the first end of the second piston rod (13) is slidably disposed in the second chamber. The cylinder (11) is provided with a first hole (111), a second hole (112), and a third hole (113). The first chamber is connected to the first hole (111) and the second hole (112), and the second chamber is connected to the first hole (111) and the third hole (113). The telescopic structure (1) has an expanded state in which the first piston rod (12) and the second piston rod (13) are far apart from each other, and a retracted state in which the first piston rod (12) and the second piston rod (13) are close to each other; The abutting structure (2) includes two abutting components (21), one of which is disposed at the second end of the first piston rod (12), and the other abutting component (21) is disposed at the second end of the second piston rod (13); In the injection structure, during the expansion state, the first hole (111) is connected to the output end of the injection structure; during the retraction state, the second hole (112) and the third hole (113) are both connected to the output end of the injection structure.

2. The inter-tube expander according to claim 1, characterized in that, The partition (14) surrounds a third chamber (140), and the first hole (111) communicates with the third chamber (140); The two side walls of the partition (14) are respectively provided with a fourth hole and a fifth hole, the fourth hole being connected to the first chamber and the fifth hole being connected to the second chamber.

3. The inter-tube expander according to claim 1, characterized in that, The outer wall of the cylinder body (11) is provided with a first pipe (114) and a second pipe (115), the first pipe (114) is connected to the second hole (112), and the second pipe (115) is connected to the third hole (113).

4. The inter-tube expander according to claim 3, characterized in that, Both the first pipeline (114) and the second pipeline (115) are equipped with check valves.

5. The inter-tube expander according to claim 1, characterized in that, The cylinder body (11) includes a cylinder barrel (116) and two cylinder covers (117). The two cylinder covers (117) are respectively disposed at both ends of the cylinder barrel (116) to enclose the fixed chamber. The first piston rod (12) and the second piston rod (13) are both slidably inserted through the corresponding cylinder head (117).

6. The inter-tube expander according to claim 5, characterized in that, A seal (15) is provided between the first piston rod (12) and the corresponding cylinder head (117); and / or, a seal (15) is provided between the second piston rod (13) and the corresponding cylinder head (117).

7. The inter-tube expander according to any one of claims 1-6, characterized in that, The injection structure includes an injection mechanism and an injection pipeline, wherein the inlet of the injection pipeline is connected to the output end of the injection mechanism; In the expanded state, the first hole (111) is connected to the outlet of the injection pipe; In the retracted state, both the second hole (112) and the third hole (113) are connected to the outlet of the injection pipe; A pressure monitor is installed on the injection pipeline to monitor the pressure of the medium in the injection pipeline.

8. The inter-tube expander according to any one of claims 1-6, characterized in that, The inter-pipe expander also includes a support structure (3), which is disposed on a support base, and the cylinder (11) is vertically and vertically disposed on the support structure (3).

9. The inter-tube expander according to any one of claims 1-6, characterized in that, The cylinder body (11) has a first connector (118) on its outer wall, and the first connector (118) is connected to the first hole (111).

10. The inter-tube expander according to any one of claims 1-6, characterized in that, The abutment assembly (21) includes a fixing plate (211) and a buffer (212). The fixing plate (211) is disposed at the second end of the first piston rod (12) or the second end of the second piston rod (13). The buffer (212) is disposed on the side of the fixing plate (211) facing the pipe.

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