CN114183602A

CN114183602A - Connecting device and flexible pipe

Info

Publication number: CN114183602A
Application number: CN202111281811.XA
Authority: CN
Inventors: 张树林; 鞠国领; 包德健
Original assignee: Yantai Jereh Petroleum Equipment and Technologies Co Ltd
Current assignee: Yantai Jereh Petroleum Equipment and Technologies Co Ltd
Priority date: 2021-11-01
Filing date: 2021-11-01
Publication date: 2022-03-15

Abstract

The application discloses connecting device and flexible pipe relates to the oil gas and equips the field. A connecting device includes: the sealing device comprises a first connector, a second connector and a sealing element, wherein the first connector and the second connector are detachably connected; the first connector is provided with a first channel, the second connector is provided with a second channel, and the first channel and the second channel are coaxially arranged under the condition that the first connector and the second connector are detachably connected, wherein a first matching part is arranged at one end of the first channel close to the second connector, and a second matching part is arranged at one end of the second channel close to the first connector; and the sealing element is respectively in sealing fit with the first matching part and the second matching part in the radial direction of the first connector and the second connector. A flexible pipe comprising a flexible pipe body and the above-described connection device; the flexible pipe body is connected with the first connector. The problem that inventory management and control and material are with high costs, the configuration is searched inconveniently and sealing performance is not good can be solved to this application.

Description

Connecting device and flexible pipe

Technical Field

This application belongs to oil gas and equips technical field, concretely relates to connecting device and flexible tube.

Background

The flexible pipe mainly comprises a metal joint and a pipe body, wherein the metal joint is mainly used for being connected with various devices in oil and gas field production, and in order to be matched with the metal joint, the metal joint needs to be consistent with the connection form of the end part and the outlet of the devices. However, the connecting ends of various devices have different specifications, and at this time, conversion devices of different specifications need to be stored, so that the inventory control cost and the material cost are increased, and the configuration and the search are inconvenient during installation, which affects the operation efficiency. In addition, when the conversion device is used for connecting the metal joint and the connecting end of the equipment, the problem of fluid leakage caused by poor sealing performance exists, and normal operation is influenced.

Disclosure of Invention

The purpose of the embodiment of the application is to provide a connecting device and flexible pipe, can solve the problem that inventory management and control and material are with high costs, the configuration is looked for inconveniently and sealing performance is not good.

In order to solve the technical problem, the present application is implemented as follows:

an embodiment of the present application provides a connecting device, which includes: the sealing device comprises a first connector, a second connector and a sealing element, wherein the first connector and the second connector are detachably connected;

the first connector is provided with a first channel, the second connector is provided with a second channel, and the first channel and the second channel are coaxially arranged under the condition that the first connector and the second connector are detachably connected, wherein a first matching part is arranged at one end of the first channel close to the second connector, and a second matching part is arranged at one end of the second channel close to the first connector;

and in the radial direction of the first connector and the second connector, the sealing element is respectively in sealing fit with the first matching part and the second matching part.

The embodiment of the application also provides a flexible pipe, which comprises a flexible pipe body and the connecting device;

the flexible pipe body is connected with the first connector.

In the embodiment of the application, first connector and second connector can dismantle the connection, make things convenient for the dismouting, and can realize the connection between the equipment of multiple different specifications through first connector and second connector, for example, adopt the second connector of great specification, make it be connected with one of them equipment, adopt the first connector of less specification, make it be connected with another kind of equipment, then be in the same place first connector and second connector assembly, thereby can satisfy the connection between the equipment of multiple different specifications, can need not to store the conversion equipment of different specifications to a certain extent, the inventory management and control cost has been reduced, material cost etc., and need not to look for the conversion equipment that corresponds, thereby installation rate has been improved, and then operating efficiency has been improved.

Moreover, a sealing element is arranged between the first matching part and the second matching part, and the sealing element is respectively in sealing fit with the first matching part and the second matching part in the radial direction of the first connector and the second connector, so that radial sealing is realized; compare in sealing forms such as some threaded connection, radial seal need not to apply too big tight power of going up, and when becoming flexible to some extent between first connector and the second connector, also can guarantee good leakproofness to effectively prevent the fluid in first passageway and the second passageway and reveal, based on its sealing performance is reliable, can satisfy the multiple operating mode requirement in the oil and gas field operation.

Drawings

Fig. 1 is a schematic structural view of a first form of coupling device and flexible pipe body disclosed in an embodiment of the present application;

FIG. 2 is a schematic structural diagram of a first form of seal disclosed in an embodiment of the present application;

FIG. 3 is a schematic structural diagram of a second form of coupling device and flexible pipe body as disclosed in an embodiment of the present application;

FIG. 4 is a schematic structural diagram of a third form of coupling device disclosed in embodiments of the present application;

FIG. 5 is a schematic structural diagram of a second connector connected to a portion of a structure in an oil and gas field production device according to an embodiment of the disclosure;

fig. 6 is a schematic structural diagram of the oil and gas field production equipment, the connecting device and the flexible pipe body disclosed in the embodiment of the application.

Description of reference numerals:

100-a first connector; 110 — a first channel; 120-a first groove; 130-a mating protrusion;

200-a second connector; 210-a second channel; 220-a second groove; 230-mating grooves; 231-a third annular groove; 240-a connecting portion;

300-a seal; 310-an annular sleeve; 311-convex surface; 312-a chamfer structure; 313-internal thread structure; 314-a first annular trench; 315-a second annular trench; 320-an annular projection; 330-sealing ring; 340-a sealing ring;

400-a flexible pipe body;

m-a containing space.

Detailed Description

The technical solutions in the embodiments of the present application will be clearly and completely described below with reference to the drawings in the embodiments of the present application, and it is obvious that the described embodiments are some, but not all, embodiments of the present application. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present application.

The terms first, second and the like in the description and in the claims of the present application are used for distinguishing between similar elements and not necessarily for describing a particular sequential or chronological order. It will be appreciated that the data so used may be interchanged under appropriate circumstances such that embodiments of the application may be practiced in sequences other than those illustrated or described herein, and that the terms "first," "second," and the like are generally used herein in a generic sense and do not limit the number of terms, e.g., the first term can be one or more than one. In addition, "and/or" in the specification and claims means at least one of connected objects, a character "/" generally means that a preceding and succeeding related objects are in an "or" relationship.

The embodiments of the present application are described in detail below with reference to the accompanying drawings through specific embodiments and application scenarios thereof.

With reference to fig. 1 to 6, the present application discloses a connection device, which can be applied in the field of oil and gas field operation equipment, for example, connection between oil and gas field operation equipment and a flexible pipe is realized through the connection device. The disclosed connecting device includes a first connector 100, a second connector 200, and a sealing member 300.

Wherein the first connector 100 is used for connecting with one of the devices or equipments, for example, one end of the first connector 100 is connected with the pipe body; the second connector 200 is used to connect to another device or equipment, for example, one end of the second connector 200 is connected to oil and gas field equipment. In this way, in the case where the first connector 100 and the second connector 200 are assembled, connection between two devices or apparatuses can be achieved to meet working requirements.

In order to meet the requirement of disassembly and assembly, the first connector 100 and the second connector 200 are detachably connected. In some embodiments, the modular quick connection replacement can be realized by replacing the second connector 200 with different specifications or different connection modes, so as to adapt to connection requirements of different working conditions. Based on this, can make the installation between two kinds of devices or equipment more convenient, swift to can improve the operating efficiency. Alternatively, the connection manner between the first connector 100 and the second connector 200 may include: a screw connection, a clamping connection, a flange connection, etc., and of course, the specific connection manner between the first connector 100 and the second connector 200 is not limited in the embodiment of the present application, as long as the disassembly and assembly can be facilitated.

In some embodiments, the connection device may be used in the field of oil and gas field operations for connecting devices or equipment for transferring fluids. Based on this, the first connector 100 is provided with the first passage 110, the second connector 200 is provided with the second passage 210, and in the case that the first connector 100 and the second connector 200 are detachably connected, the first passage 110 and the second passage 210 are coaxially disposed and communicate with each other, so that two devices or apparatuses for transferring fluid can be communicated. For example, the connection device is used to connect oil and gas field equipment to a tubular body.

Considering that after the first connector 100 and the second connector 200 are assembled, the fluid is easy to leak when conducting the fluid due to loose assembly or loose after being used for a period of time, thereby affecting the normal operation, in the embodiment of the present application, the connecting device further includes a sealing member 300, and the first connector 100 and the second connector 200 can be sealed through the sealing member 300, thereby effectively avoiding the leakage problem.

In order to achieve a better sealing effect, in some embodiments, a first mating portion is disposed at an end of the first passage 110 close to the second connector 200, and similarly, a second mating portion is disposed at an end of the second passage 210 close to the first connector 100, when the first connector 100 and the second connector 200 are detachably connected, one portion of the sealing member 300 is in sealing engagement with the first mating portion, and the other portion of the sealing member 300 is in sealing engagement with the second mating portion, so that the sealing member 300 is sealingly disposed between the first mating portion and the second mating portion, thereby achieving sealing in a radial direction of the first connector 100 and the second connector 200.

It should be noted here that, in order to avoid the sealing member 300 from blocking the first channel 110 and the second channel 210, a hole may be further formed in the sealing member 300 to communicate the first channel 110 with the second channel 210.

Based on the above arrangement, the first connector 100 and the second connector 200 can be detachably connected, so that the disassembly and the assembly can be facilitated, the connectors of different specifications can be conveniently replaced, the connection of devices or equipment of multiple different specifications can be realized, the conversion devices of different specifications can be omitted, the inventory management and control cost, the material cost and the like can be reduced, the corresponding conversion devices do not need to be searched, the installation speed is increased, and the operation efficiency is improved.

And, through sealing member 300 seal setting between first cooperation portion and second cooperation portion between first connector 100 and the second connector 200, radial seal has been realized, compare in some threaded connection etc. and lean on the sealed mode of extrusion mode realization, radial seal need not to exert too big tight power of going up, and when having not hard up between first connector 100 and the second connector 200, also can guarantee good leakproofness, thereby effectively prevent the fluid in first passageway 110 and the second passageway 210 from revealing, reliable based on its sealing performance, can satisfy the multiple operating mode requirement in the oil and gas field operation.

Referring to fig. 1 and 3, in order to assemble the sealing member 300 with the first connector 100 and the second connector 200, in some embodiments, the first mating portion may be provided as a first groove 120, and the first groove 120 is a through groove structure, so that the first passage 110 is communicated with the first groove 120. Alternatively, the first groove 120 may be a circular groove, a polygonal groove, or the like, and the cross-sectional area of the first groove 120 is larger than that of the first passage 110, so that a first stepped structure is formed at the end of the first connector 100. When the sealing member 300 is installed, one end of the sealing member 300 is disposed in the first groove 120, and the outer wall surface of the sealing member 300 abuts against the inner wall of the first groove 120, so that sealing is achieved in the radial direction of the first connection head 100, and fluid is prevented from leaking between the outer wall surface of one end of the sealing member 300 and the inner wall of the first groove 120 when passing through the first passage 110.

Similarly, the second matching portion may be a second groove 220, and the second groove 220 is a through groove structure, so that the second channel 210 is communicated with the second groove 220. Alternatively, the second groove 220 may be a circular groove, a multi-changeable groove, etc., and the cross-sectional area of the second groove 220 is larger than that of the second channel 210, so that a second step structure is formed at the end of the second connector 200. When the sealing member 300 is installed, the other end of the sealing member 300 is disposed in the second groove 220, and the outer wall surface of the sealing member 300 abuts against the inner wall of the second groove 220, so that a seal is achieved in the radial direction of the second connector 200, and the fluid is prevented from leaking between the outer wall surface of the other end of the sealing member 300 and the inner wall of the second groove 220 when passing through the second channel 210.

Meanwhile, as the end of the first channel 110 close to the second connector 200 forms a first step structure and the end of the second channel 210 close to the first connector 100 forms a second step structure, at this time, under the condition that the first connector 100 is detachably connected with the second connector 200, one end surface of the sealing element 300 can also abut against the bottom end surface of the first step structure, and the other end surface of the sealing element 300 can also abut against the bottom end surface of the second step structure, thereby sealing can be realized in the axial direction as well.

Based on the above arrangement, the sealing element 300 in the embodiment of the present application can form both radial sealing and axial sealing with the first connector 100 and the second connector 200, so that the sealing effect is improved to a certain extent, and further, fluid leakage is effectively prevented.

In a first form of embodiment, as shown in fig. 1 and 2, the sealing member 300 may include an annular sleeve 310 and an annular projection 320, and the annular projection 320 is disposed around an outer wall of the annular sleeve 310; also, the annular sleeve 310 has an inner cavity that communicates with the first passage 110 and the second passage 210, respectively. Alternatively, the annular sleeve 310 may be a circular cylindrical sleeve, and of course, may also be a cylindrical sleeve with other shapes, such as a square cylindrical sleeve, a regular hexagon cylindrical sleeve, and the like, and the specific shape of the annular sleeve 310 is not limited in the embodiment of the present application.

In a state where the first connector 100 is assembled with the second connector 200, an outer wall of one end of the annular sleeve 310 is interference-fitted with an inner wall of the first groove 120, and an outer wall of the other end of the annular sleeve 310 is interference-fitted with an inner wall of the second groove 220. Thus, the sealing member 300 can be ensured to have good sealing performance with the first connector 100 and the second connector 200, so that the fluid cannot leak; moreover, when the first connector 100 and the second connector 200 are loosened, the sealing member 300 is still in an interference fit state with the first connector 100 and the second connector 200, and good sealing performance can be ensured, so that safe and reliable operation can be realized.

It should be noted here that since the inner cavity of the annular sleeve 310 is communicated with the first passage 110 and the second passage 210, respectively, the inner wall of the annular sleeve 310 is also washed by the fluid when the fluid is delivered, and the annular sleeve 310 is also required to bear the pressure when the first passage 110 and the second passage 210 have a certain pressure. In this regard, the annular sleeve 310 may be a metal piece having sufficient strength to withstand erosion by the fluid and withstand high pressures, ensuring a useful life of the seal 300.

To further improve the sealing performance, an annular protrusion 320 is further provided on the outer wall of the annular sleeve 310. Under the condition of first connector 100 and the assembly of second connector 200, keep a certain distance apart from each other between the terminal surface at the notch place of first recess 120 and the terminal surface at the notch place of second recess 220, form accommodation space M, and annular protrusion 320 then sets up in accommodation space M, and annular protrusion 320 supports tightly each other with above-mentioned two terminal surfaces respectively along axial both ends face (namely, the terminal surface at the notch place of first recess 120 and the terminal surface at the notch place of second recess 220), thereby can realize axial seal to first connector 100 and second connector 200 through annular protrusion 320, outwards reveal through accommodation space M in order to prevent the fluid.

Alternatively, the annular sleeve 310 and the annular protrusion 320 may be an integral structure, i.e., integrally formed, which on the one hand facilitates manufacturing and shortens manufacturing period, and on the other hand improves strength, ensuring that the sealing member 300 can withstand high pressure and is not eroded by fluid.

Referring to fig. 2, in some embodiments, the outer walls of the two ends of the annular sleeve 310 are respectively provided with a convex surface 311 protruding from the outer wall, when assembled, the convex surface 311 of the outer wall of one end of the annular sleeve 310 abuts against the inner wall of the first groove 120 and forms an interference fit, so as to ensure the radial seal between the annular sleeve 310 and the first connector 100, and the convex surface 311 of the outer wall of the other end of the annular sleeve 310 abuts against the inner wall of the second groove 220 and forms an interference fit, so as to ensure the radial seal between the annular sleeve 310 and the second connector 200. Therefore, the sealing performance can be ensured, the fluid is prevented from leaking, and safe and reliable operation is realized.

With continued reference to fig. 2, in order to facilitate the assembly of the sealing member 300 with the first connector 100 and the second connector 200, respectively, chamfer structures 312 are provided at outer walls of both ends of the annular sleeve 310, respectively. At the time of assembly, the fitting of the annular sleeve 310 to the first groove 120 or the second groove 220 may be guided by the chamfered structure 312, thereby improving the assembly efficiency and the assembly accuracy.

Alternatively, the angle range of the chamfer structure 312 may be 1 ° to 10 °, including 1 °, 3 °, 5 °, 8 °, 10 °, etc., and of course, the specific angle value is not limited in the embodiment of the present application.

In other embodiments, the two ends of the annular sleeve 310 may be provided with arc structures, which may also facilitate assembly.

With continued reference to fig. 2, to facilitate the removal of the sealing element 300, in the embodiment of the present application, the inner wall of the annular sleeve 310 is provided with an internal thread structure 313, and during the removal, a rod with an external thread structure can be screwed into the internal thread structure 313 of the annular sleeve 310, and then the rod is pulled to overcome the resistance of the interference fit, so that the sealing element 300 can be removed from the first connector 100 or the second connector 200.

Alternatively, the form of the seal 300 may be a MX type metal seal, which ensures good sealing and long life, ensuring proper operation of the field.

In a second form of embodiment, as shown in FIG. 3, the seal 300 may include an annular sleeve 310. The annular sleeve 310 in this embodiment has substantially the same structure as the annular sleeve 310 in the first embodiment, and thus, the description thereof is omitted.

To effect a seal, the seal 300 further includes a sealing ring 330, the sealing ring 330 being located outside the annular sleeve 310. Specifically, the outer wall of the annular sleeve 310 is provided with a first annular groove 314 and a second annular groove 315 which are arranged at intervals along the axial direction, and the first annular groove 314 and the second annular groove 315 are respectively provided with a sealing ring 330. To ensure sealing performance, the corresponding sealing rings 330 may be partially inserted into the first annular groove 314 and the second annular groove 315, and the sealing rings 330 may be partially protruded from the first annular groove 314 and the second annular groove 315.

Under the condition that the sealing element 300 is assembled with the first connector 100 and the second connector 200 respectively, one end of the annular sleeve 310 is arranged in the first groove 120, and the outer side surface of the sealing ring 330 arranged in the first annular groove 314 abuts against the inner wall of the first groove 120, so that the sealing between the one end of the annular sleeve 310 and the inner wall of the first groove 120 is realized through the sealing ring 330 arranged in the first annular groove 314; similarly, the other end of the annular sleeve 310 is disposed in the second groove 220, and the outer side surface of the sealing ring 330 disposed in the second annular groove 315 abuts against the inner wall of the second groove 220, so that the other end of the annular sleeve 310 and the inner wall of the second groove 220 are sealed by the sealing ring 330 disposed in the second annular groove 315.

Of course, in other embodiments, grooves may be formed on the inner walls of the first groove 120 and the second groove 220 to mount the sealing ring 330, and at this time, the sealing ring 330 may also be used to seal the annular sleeve 310 with the first groove 120 and the second groove 220, so as to ensure the sealing effect between the first connector 100 and the second connector 200.

In the sealing element 300 of the above form, the annular sleeve 310 may be made of a metal member, and the sealing ring 330 may be made of a non-metal member, such as the sealing ring 330 made of a rubber material, the sealing ring 330 made of a thermoplastic material, and the like, which can meet the requirements for use under high pressure conditions.

In the third form of embodiment, as shown in fig. 4, one of the first and second fitting portions is a fitting protrusion 130, the other is a fitting groove 230, and the fitting protrusion 130 is matched with the fitting groove 230 to realize fitting installation. Alternatively, the first matching portion may be the matching protrusion 130, and the second matching portion may be the matching groove 230, and of course, the first matching portion may also be the matching groove 230, and the second matching portion may be the matching protrusion 130, which is not limited specifically.

To effect a seal, the seal 300 includes a seal ring 340, a third annular groove 231 is provided in the inner wall of the mating groove 230, and the seal ring 340 is at least partially disposed in the third annular groove 231.

Based on the above arrangement, in the case that the first connector 100 is used for assembling the second connector 200, the fitting protrusion 130 is at least partially inserted into the fitting groove 230, and at this time, the inner wall of the sealing ring 340 can abut against the outer wall of the fitting protrusion 130, so that the sealing between the fitting protrusion 130 and the fitting groove 230 can be realized.

Of course, in other embodiments, a groove may be further formed on an outer wall of the mating protrusion 130 to mount the sealing ring 340 to the mating protrusion 130, and at this time, the outer wall of the sealing ring 340 may abut against an inner wall of the mating groove 230, so that a good sealing effect may be achieved.

Based on above-mentioned three kinds of sealed forms, this application embodiment has realized the good sealed between first connector 100 and the second connector 200, has effectively avoided appearing leaking the problem between the two, has guaranteed the normal clear of oil and gas field operation.

Referring to fig. 1, 3 and 4, in some embodiments, the first connector 100 is threadably connected to the second connector 200. Alternatively, the first connector 100 may be provided with an external thread, and the second connector 200 may be provided with an internal thread, however, the first connector 100 may also be provided with an internal thread, and the second connector 200 may be provided with an external thread, which is not limited specifically.

Based on threaded connection, can make the dismouting more convenient between first connector 100 and the second connector 200, can improve the operating efficiency to a certain extent.

In other embodiments, a clamping connection, a flange connection, or the like may be used between the first connector 100 and the second connector 200, and the specific form is not limited as long as convenient detachment and installation can be achieved.

Since the connecting device can connect two devices or equipment, in order to improve the working efficiency, a connecting portion 240 is provided at an end of the second connector 200 facing away from the first connector 100, and the connecting portion 240 may be one of a union structure (as shown in fig. 5), a flange structure and a thread structure. Based on this, quick assembly and disassembly between second connector 200 and one of them device or equipment can be realized to can improve the operating efficiency.

It should be noted that, a specific connection manner between the second connector 200 and one of the apparatuses or devices is not limited, as long as it is convenient to assemble and disassemble.

Based on the above arrangement, the embodiment of the application also discloses a flexible pipe, which can be connected with oil and gas field operation equipment, as shown in fig. 6.

The disclosed flexible pipe includes a flexible pipe body 400 and the above-described connection device, wherein the flexible pipe body 400 is connected with the first connection joint 100.

Alternatively, the flexible pipe body 400 and the first connector 100 may be fixedly connected, for example, by a fastening method, an adhesive method, a welding method, and the like, and the specific form is not limited. Based on this, the firmness and stability of the connection between the flexible pipe body 400 and the first connection joint 100 can be ensured to prevent problems such as breakage and leakage.

In summary, in the embodiment of the present application, the first connector 100 and the second connector 200 are detachably connected to each other, so that the convenience of assembly and disassembly can be realized, thereby improving the operation efficiency, and the sealing performance between the first connector 100 and the second connector 200 is ensured by adopting a radial sealing manner, thereby effectively preventing leakage, and ensuring the reliability and safety of operation; compare in some modes of adopting a plurality of complicated part assembly to be equipped with to reach sealed effect, connecting device simple structure in the embodiment of this application, the dismouting is convenient.

In addition, the connection mode and the structural form of the second connector 200 can be changed according to actual working conditions, and the connection mode comprises union, flange, thread and the like, so that modular connection can be realized, and the universality of operation is further realized.

While the present embodiments have been described with reference to the accompanying drawings, it is to be understood that the invention is not limited to the precise embodiments described above, which are meant to be illustrative and not restrictive, and that various changes may be made therein by those skilled in the art without departing from the spirit and scope of the invention as defined by the appended claims.

Claims

1. A connection device, comprising: a first connector (100) and a second connector (200) which are detachably connected, and a sealing member (300) which seals the first connector (100) and the second connector (200);

the first connector (100) is provided with a first channel (110), the second connector (200) is provided with a second channel (210), the first channel (110) and the second channel (210) are coaxially arranged under the condition that the first connector (100) is detachably connected with the second connector (200), one end of the first channel (110) close to the second connector (200) is provided with a first matching part, and one end of the second channel (210) close to the first connector (100) is provided with a second matching part;

in the radial direction of the first connector (100) and the second connector (200), the sealing element (300) is in sealing fit with the first matching part and the second matching part respectively.

2. The connecting device according to claim 1, wherein the first mating portion is a first groove (120) communicating with the first channel (110), and the second mating portion is a second groove (220) communicating with the second channel (210);

one end of the sealing element (300) is arranged in the first groove (120) and is tightly abutted against the inner wall of the first groove (120), and the other end of the sealing element (300) is arranged in the second groove (220) and is tightly abutted against the inner wall of the second groove (220).

3. The connection device according to claim 2, characterized in that the seal (300) comprises an annular sleeve (310) and an annular projection (320) arranged on the outer wall of the annular sleeve (310), the inner cavity of the annular sleeve (310) being in communication with the first passage (110) and the second passage (210), respectively;

one end of the annular sleeve (310) is in interference fit with the inner wall of the first groove (120), and the other end of the annular sleeve (310) is in interference fit with the inner wall of the second groove (220);

an accommodating space (M) is formed between the end face where the notch of the first groove (120) is located and the end face where the notch of the second groove (220) is located, and the annular protrusion (320) is arranged in the accommodating space (M) and tightly abutted to the two end faces respectively.

4. The connecting device according to claim 3, wherein the outer walls of the two ends of the annular sleeve (310) are respectively provided with a convex surface (311) protruding from the outer wall, and the convex surfaces (311) form an interference fit with the inner wall of the first groove (120) or the inner wall of the second groove (220);

and/or the outer walls of the two ends of the annular sleeve (310) are respectively provided with a chamfer structure (312);

and/or the inner wall of the annular sleeve (310) is provided with an internal thread structure (313).

5. The connection device according to claim 2, characterized in that the seal (300) comprises an annular sleeve (310) and a sealing ring (330);

the outer wall of annular cover (310) is equipped with along first annular groove (314) and second annular groove (315) that axial interval set up, sealing washer (330) set up respectively in first annular groove (314) with second annular groove (315), the one end of annular cover (310) with through locating between the inner wall of first recess (120) first annular groove (314) sealing washer (330) is sealed, the other end of annular cover (310) with through locating between the inner wall of second recess (220) second annular groove (315) sealing washer (330) is sealed.

6. The connecting device according to claim 1, wherein one of the first and second fitting portions is a fitting projection (130), and the other is a fitting groove (230) fitted with the fitting projection (130);

the sealing element (300) comprises a sealing ring (340), a third annular groove (231) is formed in the inner wall of the matching groove (230) or the outer wall of the matching protrusion (130), the sealing ring (340) is at least partially arranged in the third annular groove (231), and the sealing ring (340) abuts against the outer wall of the matching protrusion (130) or the inner wall of the matching groove (230).

7. The connection device according to any one of claims 1 to 6, characterized in that the first connection head (100) is screwed to the second connection head (200).

8. The connecting device according to claim 1, characterized in that an end of the second connector (200) facing away from the first connector (100) is provided with a connecting portion (240), the connecting portion (240) being one of a union structure, a flange structure and a threaded structure.

9. A flexible pipe, comprising a flexible pipe body (400) and a connection device according to any one of claims 1 to 8;

the flexible pipe body (400) is connected with the first connection joint (100).

10. The flexible pipe as claimed in claim 9, wherein the flexible pipe body (400) is connected to the first coupling head (100) by crimping, bonding or welding.