CN112050003A

CN112050003A - Double-seal double-socket structure of composite pipe and composite pipe

Info

Publication number: CN112050003A
Application number: CN202011038354.7A
Authority: CN
Inventors: 罗昌斌
Original assignee: Guangdong Smart Bi Pipe Technology Co ltd
Current assignee: Guangdong Smart Bi Pipe Technology Co ltd
Priority date: 2020-09-28
Filing date: 2020-09-28
Publication date: 2020-12-08

Abstract

The invention discloses a double-sealing double-socket structure of a composite pipe, which comprises an outer pipe socket structure and an inner pipe socket structure arranged in the outer pipe socket structure, wherein the outer pipe socket structure comprises an outer pipe socket section and an outer pipe socket section which are spliced together; the inner pipe socket structure comprises an inner pipe socket section and an inner pipe socket section which are connected together in an inserting mode, an inner pipe sealing structure and an inner pipe connecting structure capable of limiting the separation of the inner pipe socket section and the inner pipe socket section are arranged between the inner side wall of the inner pipe socket section and the outer side wall of the inner pipe socket section. The double-sealing double-socket structure of the composite pipe comprises a two-layer connecting structure and a two-layer sealing structure, and is high in connecting strength and good in sealing performance.

Description

Double-seal double-socket structure of composite pipe and composite pipe

Technical Field

The invention relates to a composite pipe double-seal double-socket structure and a composite pipe.

Background

In order to ensure the strength of the pipeline and simultaneously improve the corrosion resistance, the composite pipe is produced. The steel-plastic composite pipe is the most common one of the composite pipes, is widely applied to various projects such as water supply and drainage and provides convenience for life of people.

The common steel-plastic composite pipe generally has a structure including an outer pipe made of steel and an inner polymer pipe disposed inside the outer pipe. In order to adapt to geological settlement, the two ends of the outer pipe are respectively provided with a bellmouth and a socket, a gap is reserved between the bellmouth and the socket so that the connected pipes can rotate relatively by a certain angle, in order to avoid damage to the inner pipe when geological settlement occurs, the inner pipe is designed to be shorter than the outer pipe, when the two composite pipes are connected together, only the outer pipe is connected, and the inner pipes of the two composite pipes are not in contact with each other.

The socket structure of the steel-plastic composite pipe has the following problems: firstly, only two outer pipes are connected together, and a gap exists between the two outer pipes, so that the connection strength is low; the inner pipes of the second and the second composite pipes are in an open structure, and water in the composite pipes can contact the inner wall of the outer pipe, so that the bell and spigot of the outer pipe is easy to corrode and rust; thirdly, sealing is carried out only by means of the O-shaped ring between the two outer pipes, when geological settlement occurs, the relative positions of the two outer pipes which are connected together are changed, so that the depth of a sealing groove which is arranged between the two outer pipes is changed, the sealing groove on one side of each outer pipe is deepened, the sealing groove on the other side opposite to the sealing groove is shallowed, the volume of the O-shaped ring which is arranged in the sealing groove cannot be increased, a gap is generated between the sealing groove and the O-shaped ring, further, the leakage condition occurs, and the sealing performance is poor; and fourthly, the two composite pipes are connected together by generally adopting a flange structure, the installation is complicated and time-consuming, and the working efficiency is low.

Disclosure of Invention

In view of this, an object of the present invention is to provide a dual-sealing dual socket structure for a composite pipe, which includes a two-layer connection structure and a two-layer sealing structure, and has high connection strength and good sealing performance.

The invention also aims to provide a composite pipe, and when one end and the other end of the composite pipe are connected together, the double-sealing double-socket structure of the composite pipe can be formed.

The technical scheme adopted by the invention for realizing the purpose is as follows:

a double-sealing double-socket structure for a composite pipe comprises: an outer pipe socket structure and an inner pipe socket structure arranged in the outer pipe socket structure,

the outer pipe socket structure comprises an outer pipe socket section and an outer pipe socket section which are spliced together, an outer pipe sealing structure is arranged between the outer pipe socket section and the outer pipe socket section, the outer side wall of the outer pipe socket section is provided with an outer pipe socket connecting part, the inner side wall of the outer pipe socket section is provided with an outer pipe socket connecting part, and the outer pipe socket connecting part is connected with the outer pipe socket connecting part in a matched manner, so that the outer pipe socket section and the outer pipe socket section can rotate relatively and can be limited to be separated after the outer pipe socket section and the outer pipe socket section rotate relatively;

the inner pipe socket structure comprises an inner pipe socket section and an inner pipe socket section which are connected in an inserting mode, wherein an inner pipe sealing structure and an inner pipe connecting structure capable of limiting the inner pipe socket section and the inner pipe socket section to be separated are arranged between the inner side wall of the inner pipe socket section and the outer side wall of the inner pipe socket section.

In a preferred embodiment of the present invention, the right end of the outer tube socket section is open, the outer tube socket section is inserted into the outer tube socket section through the right end of the outer tube socket section, the inner side wall of the outer tube socket section is provided with a first spherical concave surface located on the right side of the outer tube socket connecting portion, and the outer side wall of the outer tube socket section is provided with a first spherical convex surface attached to the first spherical concave surface.

In a preferred embodiment of the present invention, the outer tube sealing structure is disposed between the first spherical concave surface and the first spherical convex surface.

In a preferable aspect of the present invention, the outer tube sealing structure includes a first sealing ring fixedly disposed on the outer tube socket section, an outer side surface of the first sealing ring is a spherical convex surface concentric with the first spherical convex surface, and an outer side surface of the first sealing ring slightly protrudes from the first spherical convex surface and is in interference fit with the first spherical concave surface.

In a preferred embodiment of the present invention, the material of the first sealing ring is rubber, polytetrafluoroethylene, graphite, or sealant.

In a preferred embodiment of the present invention, a first flat wall section lower than the first spherical convex surface is disposed on an outer side wall of the outer tube socket section, a step is formed between the first flat wall section and the first spherical convex surface, the first sealing ring is sleeved on the first flat wall section, a pressing plate capable of pressing the first sealing ring against the step is further sleeved on the first flat wall section, and the pressing plate is screwed with the outer tube socket section.

In a preferred embodiment of the present invention, a first flat wall section lower than the first spherical convex surface is disposed on an outer side wall of the outer tube socket section, a step is formed between the first flat wall section and the first spherical convex surface, and the first sealing ring is sleeved on the first flat wall section and is fixedly bonded to the step.

In a preferred scheme of the invention, the outer pipe bell mouth connecting part comprises a plurality of bell mouth inverted teeth which are arranged on the inner side wall of the outer pipe bell mouth section in a surrounding way, a tooth socket is formed between every two adjacent bell mouth inverted teeth, the left side wall of the tooth groove is provided with a second spherical concave surface which is concentric with the first spherical concave surface, the outer pipe socket connecting part comprises a plurality of socket inverted teeth which are arranged on the outer side wall of the outer pipe socket section in a surrounding way, the left side wall of the socket inverted tooth is provided with a second spherical convex surface which is jointed with the second spherical concave surface, a space for the socket section of the outer pipe to rotate relative to the socket section of the outer pipe is reserved between the right side wall of the socket inverted tooth and the right side wall of the tooth groove, when the outer pipe socket section rotates relative to the outer pipe socket section, the socket inverted teeth are meshed with the tooth grooves to limit the outer pipe socket section from being separated from the outer pipe socket section.

In a preferred aspect of the present invention, the crest diameter of each socket pawl is smaller than the crest diameter of the corresponding socket pawl.

In a preferred embodiment of the present invention, the inner sidewall of the socket section of the inner tube is provided with a third spherical concave surface concentric with the first spherical concave surface, and the outer sidewall of the socket section of the inner tube is provided with a third spherical convex surface attached to the third spherical concave surface.

In a preferred aspect of the present invention, the inner tube sealing structure includes a sealing groove disposed on the third spherical convex surface, and a second sealing ring disposed on the sealing groove and compressed by the third spherical concave surface.

In a preferred embodiment of the present invention, the inner tube connecting structure includes an annular groove disposed on an inner sidewall of the socket section of the inner tube and an annular protrusion disposed on an outer sidewall of the socket section of the inner tube, and each annular protrusion is clamped into a corresponding annular groove with a gap therebetween.

In a preferred embodiment of the present invention, the inner pipe socket section is disposed inside the outer pipe socket section, and the inner pipe socket section is disposed inside the outer pipe socket section.

In a preferred embodiment of the present invention, a fourth spherical concave surface concentric with the first spherical concave surface is disposed on the left inner wall of at least one annular groove, a fourth spherical convex surface attached to the fourth spherical concave surface is disposed on the left side wall of the annular protrusion, and the gap is disposed between the right side wall of the annular protrusion and the right inner wall of the annular groove.

In a preferred aspect of the present invention, a second flat wall section is provided at a left end of an outer side wall of the socket section of the inner tube, a third flat wall section corresponding to the third flat wall section is provided on an inner wall of the socket section of the inner tube, and a gap is left between the second flat wall section and the third flat wall section.

In a preferred embodiment of the present invention, the inner tube socket section is disposed inside the outer tube socket section, and the inner tube socket section is disposed inside the outer tube socket section.

In a preferable scheme of the invention, a socket step is arranged on the outer side wall of the socket section of the inner pipe, a fifth spherical concave surface which is concentric with the first spherical concave surface is arranged on the socket step, and a fifth spherical convex surface which is attached to the fifth spherical concave surface is arranged on the left end surface of the socket section of the inner pipe.

The composite pipe comprises an outer pipe and an inner pipe arranged in the outer pipe, wherein one end of the outer pipe is provided with an outer pipe socket section of a composite pipe double-sealing double-socket structure, the other end of the outer pipe is provided with an outer pipe socket section of a composite pipe double-sealing double-socket structure, the inner pipe socket section of a composite pipe double-sealing double-socket structure is arranged at one end of the inner pipe, and the inner pipe socket section of a composite pipe double-sealing double-socket structure is arranged at the other end of the inner pipe.

The invention has the beneficial effects that:

first, in the invention, after two composite pipes are inserted together, the inner pipe connecting structure can limit the two composite pipes to be separated under the condition of no geological settlement, and meanwhile, the inner pipe sealing structure and the outer pipe sealing structure can ensure the sealing of the inner pipe socket structure, so that the outer pipe is prevented from being corroded due to the fact that water in the pipe contacts the outer pipe.

Secondly, socket inverted teeth are adopted in the socket connecting part of the outer pipe, and the socket section of the outer pipe are only required to be spliced together, and meanwhile, the socket section of the inner pipe and the socket section of the inner pipe are spliced together to complete installation, so that convenience and rapidness are realized; when the geology subsides, two compound pipes rotate relatively, and the socket pawl is interlock with the tooth's socket pawl's tooth's socket, can further promote joint strength, avoids leading to two compound pipes to break away from because of the pressure that the geology subsides.

Third, first spherical concave surface and first spherical convex surface can play the effect of confirming the rotation center, and when taking place the geology and subside, outer tube socket section and outer tube socket section use centre of sphere P point to rotate relatively as the center, and first spherical concave surface and first spherical convex surface also produce relative sliding thereupon, and first sealing washer keeps hugging closely with first spherical concave surface throughout, and the leakproofness is good, and joint strength is high.

And the fourth sealing structure of the inner pipe adopts a sealing groove arranged on the third spherical convex surface and a second sealing ring which is arranged on the sealing groove and is compressed by the third spherical concave surface. When the pipeline joint is bent due to geological settlement, the inner pipe socket section and the inner pipe socket section rotate around the point P of the sphere center in the same way, the third spherical concave surface and the third spherical convex surface rotate relatively and slide for a small distance, the distance between the third spherical concave surface and the bottom surface of the sealing groove is unchanged in the process, and the second sealing ring is kept in a compression state and can keep excellent sealing performance all the time.

Drawings

FIG. 1 is a schematic structural view of a composite pipe in example 1 of the present invention;

fig. 2 is a schematic structural diagram of a double-seal double-socket structure of a composite pipe in embodiment 1 of the present invention;

FIG. 3 is a schematic structural view of one end of a composite pipe according to example 1 of the present invention;

FIG. 4 is a schematic structural view of the other end of the composite pipe of example 1 of the present invention;

fig. 5 is a partially enlarged view of a portion a in fig. 2;

FIG. 6 is a schematic view showing a connecting structure of inner pipes in example 2 of the present invention;

FIG. 7 is a schematic view showing a connecting structure of inner pipes in example 3 of the present invention;

FIG. 8 is a schematic view showing a female pipe fitting structure in embodiment 4 of the present invention;

fig. 9 is a partially enlarged view of a portion B in fig. 8.

Detailed Description

The technical solution in the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings.

It should be noted that all the directional indicators (such as up, down, left, right, front, and rear …) in the embodiment of the present invention are only used to explain the relative position relationship between the components, the movement situation, etc. in a specific posture (as shown in the drawing), and if the specific posture is changed, the directional indicator is changed accordingly. In addition, the descriptions related to "preferred", "less preferred", etc. in the present invention are for descriptive purposes only and are not to be construed as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, a feature defined as "preferred" or "less preferred" may explicitly or implicitly include at least one such feature. In addition, technical solutions between various embodiments may be combined with each other, but must be realized by a person skilled in the art, and when the technical solutions are contradictory or cannot be realized, such a combination should not be considered to exist, and is not within the protection scope of the present invention.

Referring to fig. 1, a composite pipe includes an outer pipe and an inner pipe disposed within the outer pipe, one end of the outer pipe is provided with an outer pipe socket section 1, the other end of the outer pipe is provided with an outer pipe socket section 2, one end of the inner pipe is provided with an inner pipe socket section 3, and the other end of the inner pipe is provided with an inner pipe socket section 4. The inner pipe socket section 3 and the outer pipe socket section 1 can be positioned at the same end of the composite pipe, and correspondingly, the inner pipe socket section 4 and the outer pipe socket section 2 are both positioned at the other end of the composite pipe; also can set up inner tube bell mouth section 3 and outer tube socket section 2 in the same one end of compound pipe, correspondingly, inner tube socket section 4 all is located the other end of compound pipe with outer tube bell mouth section 1.

Referring to fig. 2 to 8, two composite pipes are connected by socket to form a double-sealing double-socket structure of the composite pipe.

Example 1

Referring to fig. 2 to 5, the present embodiment proposes a composite pipe double-sealing double socket structure, which includes an outer pipe socket structure and an inner pipe socket structure disposed inside the outer pipe socket structure.

Outer tube socket structure is including pegging graft outer tube bellmouth section 1 and outer tube socket section 2 together, outer tube bellmouth section 1 and outer tube socket section 2 generally adopt steel, rigid material such as aluminum alloy, the lateral wall of outer tube socket section 2 is provided with outer tube socket connecting portion, the inside wall of outer tube bellmouth section 1 is provided with outer tube bellmouth connecting portion, outer tube socket connecting portion are connected with outer tube bellmouth connecting portion cooperation, so that outer tube bellmouth section 2 and outer tube bellmouth section 1 can rotate relatively and can restrict the two and break away from after outer tube socket section 2 and outer tube bellmouth section 1 rotate relatively.

The inner pipe socket structure comprises an inner pipe socket section 3 and an inner pipe socket section 4 which are spliced together, wherein the inner pipe socket section 3 and the inner pipe socket section 4 are made of materials with a little elasticity, such as PE, PP-R, PVC and HDPE, and the like. An inner pipe sealing structure and an inner pipe connecting structure capable of limiting the separation of the inner pipe socket section 3 and the inner pipe socket section 4 are arranged between the inner side wall of the inner pipe socket section 3 and the outer side wall of the inner pipe socket section 4.

In this embodiment, two compound pipe bearings are inserted together the back, and under the condition that does not take place geology and subside, two compound pipes of inner tube connection structure can restrict break away from, and simultaneously, the seal of inner tube socket joint structure can be guaranteed to the inner tube seal structure, avoids intraductal water to contact the outer tube and leads to the outer tube to be corroded. When the geology subsides, two compound pipes rotate relatively, and outer tube socket connecting portion interlock each other with outer tube bellmouth connecting portion, can further promote joint strength, avoid leading to two compound pipes to break away from because of the pressure that the geology subsides.

In this embodiment, the right end opening of the outer tube socket section 1 and the outer tube socket section 2 are inserted into the inner portion of the outer tube socket section 1 through the right end opening of the outer tube socket section 1.

The inner pipe socket section 3 and the outer pipe socket section 1 are located at the same end of the composite pipe, and the inner pipe socket section 4 and the outer pipe socket section 2 are located at the other end of the composite pipe. Namely: the inner pipe socket section 3 is arranged in the outer pipe socket section 1, and the inner pipe socket section 4 is arranged in the outer pipe socket section 2.

Referring to fig. 5, the inner side wall of the outer tube socket section 1 is provided with a first spherical concave surface 11 located on the right side of the outer tube socket connecting portion, the outer side wall of the outer tube socket section 2 is provided with a first spherical convex surface 21 attached to the first spherical concave surface 11, and an outer tube sealing structure is further arranged between the first spherical concave surface 11 and the first spherical convex surface 21.

Preferably, the outer tube sealing structure includes a first sealing ring 51 fixedly disposed on the outer tube socket section 2, an outer side surface of the first sealing ring 51 is a spherical convex surface concentric with the first spherical convex surface 21, and an outer side surface of the first sealing ring 51 slightly protrudes from the first spherical convex surface 21 and is in interference fit with the first spherical concave surface 11. The material of the first seal ring 51 may be rubber, polytetrafluoroethylene, graphite, sealant, or the like, and a material having a high hardness such as polytetrafluoroethylene is preferable.

The first spherical concave surface 11 defines a sphere whose center P should be located on the central axis of the outer tube socket section 1 or in the vicinity of the central axis of the outer tube socket section 1.

First spherical concave surface 11 and first spherical convex surface 21 can play the effect of confirming the center of rotation, and when taking place the geology and subside, outer tube bellmouth section 1 and outer tube socket section 2 use the centre of sphere P point to rotate relatively as the center, and first spherical concave surface 11 and first spherical convex surface 21 also produce relative sliding thereupon, and first sealing washer 51 keeps hugging closely with first spherical concave surface 11 throughout, and the leakproofness is good, and joint strength is high.

In a scheme of this embodiment, a first flat wall section 22 lower than the first spherical convex surface 21 is provided on an outer side wall of the outer tube socket section 2, a step is formed between the first flat wall section 22 and the first spherical convex surface 21, the first flat wall section 22 is sleeved with the first sealing ring 51, a pressing plate 52 capable of pressing the first sealing ring 51 against the step is further sleeved on the first flat wall section 22, and the pressing plate 52 is screwed with the outer tube socket section 2. The two pressing plates 52 are generally spliced into a circular ring shape, and the annular first sealing ring 51 is pressed tightly, so that the outer side surface of the first sealing ring 51 and the first spherical concave surface 11 are kept in a pressed state.

In another aspect of the present embodiment, the first sealing ring 51 may also be fixed to the step by bonding.

Referring to fig. 5, the outer tube socket connecting portion includes that a plurality of encircles and sets up in the socket pawl 12 of outer tube socket section 1 inside wall, form a tooth's socket between per two adjacent socket pawl 12, the left side wall of tooth's socket is provided with the spherical concave surface 13 of second with first spherical concave surface 11 common sphere center, outer tube socket connecting portion includes that a plurality of encircles and sets up in the socket pawl 23 of outer tube socket section 2 outside wall, the left side wall of socket pawl 23 is provided with the spherical convex surface 24 of second that laminates mutually with the spherical concave surface 13 of second, reserve between the right side wall of socket pawl 23 and the right side wall of tooth's socket and supply outer tube socket section 1 to break away from for outer tube socket section 2, when outer tube socket section 1 rotates for outer tube socket section 2, socket pawl 23 and tooth's socket interlock are in order to restrict outer tube socket section 1 and outer tube socket section 2 and break away from.

The number of the socket inverted teeth 23 and the tooth grooves is preferably 2, and the tooth top diameter of each socket inverted tooth 23 is slightly smaller than that of the corresponding socket inverted tooth 12, so that the outer pipe socket section 2 can be inserted into the outer pipe socket section 1 without hindrance.

The outer pipe socket connecting part and the outer pipe socket connecting part adopt the structural form, and the installation can be completed by only inserting the outer pipe socket section 1 and the outer pipe socket section 2 together and inserting the inner pipe socket section 3 and the inner pipe socket section 4 together, so that the installation is convenient and fast. After the two composite pipe bearings are inserted together, the outer pipes of the two composite pipes can be locked by relatively rotating for a slight angle, so that higher connection strength is ensured.

Referring to fig. 5, the inner sidewall of the inner tube socket section 3 is provided with a third spherical concave surface 31 which is concentric with the first spherical concave surface 11, and the outer sidewall of the inner tube socket section 4 is provided with a third spherical convex surface 41 which is attached to the third spherical concave surface 31. The inner pipe seal structure includes a seal groove 42 provided in the third spherical convex surface 41, and a second seal ring 6 provided in the seal groove 42 and pressed by the third spherical concave surface 31. By adopting the inner pipe sealing structure, when the pipeline joint is bent due to geological settlement, the inner pipe bell mouth section 3 and the inner pipe socket section 4 rotate around the point P of the sphere center, the third spherical concave surface 31 and the third spherical convex surface 41 relatively rotate and slide for a small distance, the distance between the third spherical concave surface 31 and the bottom surface of the sealing groove 42 is unchanged in the process, the second sealing ring 6 is kept in a compression state, and excellent sealing performance can be always kept.

In this embodiment, the inner pipe connection structure includes an annular groove 33 disposed on the inner side wall of the inner pipe socket section 3 and an annular protrusion 43 disposed on the outer side wall of the inner pipe socket section 4, and each annular protrusion 43 is clamped into a corresponding annular groove 33. The tooth shape of the annular projection 43 is triangular.

In this embodiment, a fourth spherical concave surface 34 concentric with the first spherical concave surface 11 is disposed on the left inner wall of at least one annular groove 33, a fourth spherical convex surface 44 attached to the fourth spherical concave surface 34 is disposed on the left side wall of the annular protrusion 43, and the gap 7 is disposed between the right side wall of the annular protrusion 43 and the right inner wall of the annular groove 33.

Referring to fig. 5, the left end of the outer side wall of the inner socket section 4 is provided with a second flat wall section 45, the inner wall of the inner socket section 3 is provided with a third flat wall section 35 corresponding to the third flat wall section 35, and a gap 7 is left between the second flat wall section 45 and the third flat wall section 35.

Example 2

Fig. 6 shows a partial structure of embodiment 2 of the present invention, and this embodiment has a similar structure to embodiment 1, except for the inner pipe connection structure between the inner pipe socket section 3 and the inner pipe socket section 4. In this embodiment, the inner tube connection structure includes an annular groove 33 disposed on the inner side wall of the inner tube socket section 3 and an annular protrusion 43 disposed on the outer side wall of the inner tube socket section 4, each annular protrusion 43 is clamped into a corresponding annular groove 33, the tooth shape of the annular protrusion 43 is triangular, a gap 7 is left between the left side wall of the annular protrusion 43 and the left side inner wall of the annular groove 33, and a gap 7 is also left between the right side wall of the annular protrusion 43 and the right side inner wall of the annular groove 33.

Example 3

Fig. 7 shows a partial structure of embodiment 3 of the present invention, and this embodiment has a similar structure to embodiment 1, except for the inner pipe connection structure between the inner pipe socket section 3 and the inner pipe socket section 4. In this embodiment, the inner tube connection structure includes the annular groove 33 arranged on the inner side wall of the inner tube socket section 3 and the annular protrusion 43 arranged on the outer side wall of the inner tube socket section 4, each annular protrusion 43 is clamped into a corresponding annular groove 33, the tooth shape of the annular protrusion 43 is trapezoidal, and a gap 7 is left between the left side wall of the annular protrusion 43 and the left side inner wall of the annular groove 33, between the right side wall of the annular protrusion 43 and the right side inner wall of the annular groove 33, and between the tooth crest of the annular protrusion 43 and the groove bottom of the annular groove 33.

Example 4

Fig. 8 and 9 show an inner pipe socket structure according to embodiment 4 of the present invention, and the outer pipe socket structure in this embodiment is the same as the outer pipe socket structure in embodiment 1, except for the inner pipe socket structure.

In this embodiment, inner tube socket section 3 sets up in compound pipe with outer tube socket section 2 with the one end, and inner tube socket section 4 all is located the other end of compound pipe with outer tube socket section 1, promptly: the inner tube socket section 3 is arranged in the outer tube socket section 2, and the inner tube socket section 4 is arranged in the outer tube socket section 1.

The inner side wall of the inner pipe socket section 3 is provided with a third spherical concave surface 31 which is concentric with the first spherical concave surface 11, and the outer side wall of the inner pipe socket section 4 is provided with a third spherical convex surface 41 which is attached to the third spherical concave surface 31.

The inner pipe seal structure includes a seal groove 42 provided in the third spherical convex surface 41, and a second seal ring 6 provided in the seal groove 42 and pressed by the third spherical concave surface 31.

The inner pipe connection structure comprises an annular groove 33 arranged on the inner side wall of the inner pipe socket section 3 and annular protrusions 43 arranged on the outer side wall of the inner pipe socket section 4, and each annular protrusion 43 is clamped into a corresponding annular groove 33. The tooth shape of the annular protrusion 43 is triangular, a gap 7 is left between the left side wall of the annular protrusion 43 and the left inner wall of the annular groove 33, and a gap 7 is also left between the right side wall of the annular protrusion 43 and the right inner wall of the annular groove 33.

The outer side wall of the inner pipe socket section 4 is provided with a socket step 46, the socket step 46 is provided with a fifth spherical concave surface 47 which is concentric with the first spherical concave surface 11, and the left end face of the inner pipe socket section 3 is provided with a fifth spherical convex surface 36 which is attached to the fifth spherical concave surface 47.

The above description is only a preferred embodiment of the present invention, and not intended to limit the scope of the present invention, and all modifications and equivalents of the present invention, which can be directly or indirectly applied to other related technical fields without departing from the spirit of the present invention, are intended to be included in the scope of the present invention.

Claims

1. The utility model provides a compound pipe double containment double socket joint structure which characterized in that, it includes: an outer pipe socket structure and an inner pipe socket structure arranged in the outer pipe socket structure,

the outer pipe socket structure comprises an outer pipe socket section (1) and an outer pipe socket section (2) which are connected together in an inserted mode, an outer pipe sealing structure is arranged between the outer pipe socket section (1) and the outer pipe socket section (2), an outer pipe socket connecting part is arranged on the outer side wall of the outer pipe socket section (2), an outer pipe socket connecting part is arranged on the inner side wall of the outer pipe socket section (1), and the outer pipe socket connecting part are connected in a matched mode so that the outer pipe socket section (2) and the outer pipe socket section (1) can rotate relatively and can be limited to be separated after the outer pipe socket section (2) and the outer pipe socket section (1) rotate relatively;

the inner pipe socket structure comprises an inner pipe socket section (3) and an inner pipe socket section (4) which are connected in an inserting mode, wherein an inner pipe sealing structure and an inner pipe connecting structure capable of limiting the inner pipe socket section (3) and the inner pipe socket section (4) to be separated are arranged between the inner side wall of the inner pipe socket section (3) and the outer side wall of the inner pipe socket section (4).

2. The dual-sealing double socket structure of composite pipe according to claim 1, wherein the right end of the outer pipe socket section (1) is open and the outer pipe socket section (2) is inserted into the outer pipe socket section (1) through the right end of the outer pipe socket section (1), the inner side wall of the outer pipe socket section (1) is provided with a first spherical concave surface (11) located at the right side of the outer pipe socket connection portion, the outer side wall of the outer pipe socket section (2) is provided with a first spherical convex surface (21) fitted with the first spherical concave surface (11), and the outer pipe sealing structure is disposed between the first spherical concave surface (11) and the first spherical convex surface (21).

3. The dual sealing and double socket structure for composite pipe according to claim 2, wherein the outer pipe sealing structure comprises a first sealing ring (51) fixedly disposed on the outer pipe socket section (2), the outer side surface of the first sealing ring (51) is a spherical convex surface concentric with the first spherical convex surface (21), and the outer side surface of the first sealing ring (51) slightly protrudes from the first spherical convex surface (21) and is in interference fit with the first spherical concave surface (11).

4. The dual-sealing double-socket structure for the composite pipe according to claim 3, wherein the outer side wall of the outer pipe socket section (2) is provided with a first flat wall section (22) lower than the first spherical convex surface (21), a step is formed between the first flat wall section (22) and the first spherical convex surface (21), the sealing ring is sleeved on the first flat wall section (22), the first flat wall section (22) is further sleeved with a pressing plate (52) capable of pressing the sealing ring on the step, and the pressing plate (52) is connected with the outer pipe socket section (2).

5. The dual-sealing and double-socket structure for the composite pipe according to claim 2, wherein the socket connecting portion of the outer pipe comprises a plurality of socket inverted teeth (12) circumferentially arranged on the inner side wall of the socket section (1) of the outer pipe, a tooth socket is formed between every two adjacent socket inverted teeth (12), a second spherical concave surface (13) concentric with the first spherical concave surface (11) is arranged on the left side wall of the tooth socket, the socket connecting portion of the outer pipe comprises a plurality of socket inverted teeth (23) circumferentially arranged on the outer side wall of the socket section (2) of the outer pipe, a second spherical convex surface (24) attached to the second spherical concave surface (13) is arranged on the left side wall of the socket inverted teeth (23), and a space for the socket section (1) of the outer pipe to rotate relative to the socket section (2) of the outer pipe is reserved between the right side wall of the socket inverted teeth (23) and the right side wall of the tooth socket section of the outer pipe, when the outer pipe socket section (1) rotates relative to the outer pipe socket section (2), the socket inverted teeth (23) are meshed with the tooth grooves to limit the outer pipe socket section (1) to be separated from the outer pipe socket section (2).

6. The dual-sealing double-socket structure for compound pipes as claimed in claim 2, wherein the inner side wall of the inner pipe socket section (3) is provided with a third spherical concave surface (31) concentric with the first spherical concave surface (11), and the outer side wall of the inner pipe socket section (4) is provided with a third spherical convex surface (41) attached to the third spherical concave surface (31).

7. The dual sealing double socket structure of composite pipe according to claim 6, wherein the inner pipe sealing structure comprises a sealing groove (42) provided in the third spherical convex surface (41), and a second sealing ring (6) provided in the sealing groove (42) and compressed by the third spherical concave surface (31).

8. The dual sealing dual socket structure of composite pipe according to claim 7, wherein the inner pipe connecting structure comprises an annular groove (33) provided on the inner sidewall of the inner pipe socket section (3) and an annular protrusion (43) provided on the outer sidewall of the inner pipe socket section (4), each annular protrusion (43) is snapped into a corresponding annular groove (33) with a gap (7) left therebetween.

9. The dual sealing and double socket structure for compound pipes according to claim 8, wherein a fourth spherical concave surface (34) concentric with the first spherical concave surface (11) is provided on the left inner wall of at least one annular groove (33), a fourth spherical convex surface (44) abutting the fourth spherical concave surface (34) is provided on the left side wall of the annular protrusion (43), and the gap (7) is provided between the right side wall of the annular protrusion (43) and the right inner wall of the annular groove (33).

10. The dual-sealing double-socket structure of the compound pipe as claimed in claim 8, wherein the outer sidewall of the socket section (4) of the inner pipe is provided with a socket step (46), the socket step (46) is provided with a fifth spherical concave surface (47) concentric with the first spherical concave surface (11), and the left end surface of the socket section (3) of the inner pipe is provided with a fifth spherical convex surface (36) jointed with the fifth spherical concave surface (47).