CN108443609A - A kind of anti-corrosion high voltage-resistant multiunit tube joint and attaching method thereof - Google Patents

Abstract

The invention discloses an anti-corrosion and high-pressure resistant composite pipe joint and a connection method thereof, which belong to the technical field of non-metallic composite pipes, and include a female joint and a short joint of the composite pipe; , the two ends of the short joint of the composite pipe are respectively provided with connecting parts, and the connecting parts are connected to the female joints, and the two composite pipes with the female joints at the ends are connected through the short joints of the composite pipe during use. Through the female joint integrally formed with the composite pipe reinforcement layer, the strength of the connection between the female joint and the composite pipe is ensured, and the connection between the female joint and the short section of the composite pipe realizes the connection of the composite pipe and solves the problem of using metal joints in the prior art. The problem of corrosion resistance is solved, and the problem in the prior art that the connection strength is lower than that of the composite pipe is solved, and the connection strength and service life are increased.

Description

An anti-corrosion and high-pressure resistant composite pipe joint and its connecting method

technical field

The invention relates to the technical field of non-metallic composite pipes, in particular to an anti-corrosion and high-pressure resistant composite pipe joint and a connection method thereof.

Background technique

Non-metallic pipelines have excellent corrosion resistance, and have become an important development direction for anti-corrosion pipelines in oil and gas fields. Non-metallic pipelines for oil and gas fields have developed from the original glass steel pipes to various types of non-metallic composite pipes, including fiber-reinforced composite pipes, steel skeleton composite pipes, flexible composite pipes, and plastic alloy composite pipes. The non-metallic continuous composite pipe includes a composite pipe inner liner, a composite pipe reinforcement layer and a composite pipe outer protection layer, and the composite pipe inner liner, the composite pipe reinforcement layer and the composite pipe outer protection layer are arranged concentrically from the inside to the outside.

At present, the existing non-metallic continuous composite pipes are mainly connected by mechanical buckle-type metal joints, that is, the metal joints are inserted into the inner lining of the composite pipe, and then the metal joints are combined with the non-metallic pipe body by external seizure or internal expansion. . For example, the utility model patent with the Chinese Patent Publication No. CN 201925632 U discloses a buckle-type composite pressure pipe joint and a pipe connection structure that belong to the buckle-type metal joint connection form. There are partial metal passages in the entire non-metallic pipeline connected by metal joints, and the appearance of metal passages will bring four unfavorable factors. One is that the metal material is in direct contact with the conveyed medium. If the metal material is not properly selected, it will be corroded by the conveyed medium, which will affect the service time of the entire pipeline and increase the operation risk; second, because the metal joint is inserted into the non-metal continuous composite pipe Internal, so the diameter of the channel formed by the metal joint is smaller than the diameter of the entire pipeline, which affects the transmission efficiency of the pipeline; the third is that the bonding force between the buckled metal joint and the non-metallic pipe body is only determined by the friction between the two The joint strength is limited, which is much smaller than the tensile strength of the non-metallic pipe body; the fourth is the non-metallic composite pipeline used to transport high-pressure natural gas, and the gas medium will slowly penetrate into the The structural layer of the composite pipe, causing the structural layer of the composite pipe to fail.

For this reason, the prior art also proposes some novel connection methods, such as the Chinese Patent Publication No. CN 103267192A, which discloses a flexible composite pipe joint and its connection method. In this invention, it is proposed to use a thermoplastic material to make the joint, the joint and the composite pipe body are connected by ultrasonic welding, and the joint is connected by a flange. It is found through tests that the joint proposed by the invention and its connection method are only suitable for lower working pressure, and the pressure bearing performance of the joint is much lower than that of the composite pipe body.

Contents of the invention

Aiming at the problems existing in the prior art, the present invention provides an anti-corrosion and high-pressure resistant composite pipe joint and a connection method thereof, which are corrosion-resistant, have high connection strength and high-pressure resistance.

The present invention is achieved through the following technical solutions:

An anti-corrosion and high-pressure resistant composite pipe joint, including a female joint and a composite pipe pup joint;

The female joint is located at the end of the composite pipe, and is integrally formed with the reinforced layer of the composite pipe. The two ends of the short joint of the composite pipe are respectively provided with connecting parts, and the connecting part is connected with the female joint. A composite pipe with a female joint at the root end; the reinforced layer of the composite pipe is formed by winding the reinforced layer material on the inner lining of the composite pipe, and the female joint is formed by winding the reinforced layer material, and the reinforced layer material of the reinforced layer of the composite pipe and the female The reinforcement material of the joint is continuous.

Optionally, the female joint is provided with an internal thread, and the connecting part is provided with an external thread, the internal thread and the external thread are sealed and connected, and the threads on the connecting parts at both ends of the composite pipe puppet are in opposite directions. .

Optionally, the composite pipe sub-joint includes a composite pipe sub-joint lining layer and a composite pipe sub-joint reinforcement layer, the composite pipe sub-joint reinforcement layer is arranged outside the composite pipe sub-joint lining layer, and the composite pipe sub-joint lining layer The layer ends are provided with flanges.

Optionally, a first sealing ring is provided between the female joint and the inner lining layer of the composite pipe, and a second sealing ring is provided between the short joint of the composite pipe and the composite pipe.

Further optionally, there are two first sealing rings, and they are O-rings.

Optionally, the material of the reinforcing layer of the female joint includes wound fiber and thermosetting resin.

A connection method for an anti-corrosion and high-pressure resistant composite pipe joint, comprising:

Step S1, setting a female joint mandrel at the end of the composite pipe reinforcement layer, winding the female joint reinforcement layer material continuous with the composite pipe reinforcement layer on the mandrel to form a female joint;

Step S2, winding composite pipe sub joint reinforcement layer material on the composite pipe sub joint inner lining layer to form a composite pipe sub joint reinforcement layer, and processing connection parts at both ends of the composite pipe sub joint reinforcement layer;

Step S3, connecting the two composite pipes with female joints at the ends through the composite pipe nipple, wherein the female joints are connected with the connecting parts.

Optionally, before step S1, a filament wound commutator is arranged outside the liner;

In step S1, after winding the female joint reinforcement layer material continuous with the composite pipe reinforcement layer on the mandrel, and curing at 25-65° C. for 8-36 hours, the mandrel is taken out to obtain a female joint integrated with the composite pipe.

Optionally, in step S2, after winding the composite pipe pup joint reinforcing layer material on the composite pipe pup joint inner lining layer, curing is carried out at 45-85° C. for 5.5-8.5 hours.

Optionally, the mandrel is a threaded mold, and threads are processed on both ends of the short joint of the composite pipe.

Compared with the prior art, the present invention has the following beneficial technical effects:

The invention discloses an anti-corrosion and high-pressure resistant composite pipe joint, which comprises a female joint and a composite pipe nipple; The connecting part is connected to the female joint, and two composite pipes with female joints at the ends are connected through the short joint of the composite pipe during use. Through the female joint integrally formed with the composite pipe reinforcement layer, the strength of the connection between the female joint and the composite pipe is ensured, and the connection between the female joint and the short section of the composite pipe realizes the connection of the composite pipe and solves the problem of using metal joints in the prior art. The problem of corrosion resistance is solved, and the problem in the prior art that the connection strength is lower than that of the composite pipe is solved, and the connection strength and service life are increased.

Furthermore, the female joint and the short joint of the composite pipe are sealed by threads, the connection is reliable, and the disassembly and maintenance are convenient.

The invention discloses a connection method of an anti-corrosion and high-pressure resistant composite pipe joint. A female joint core mold is arranged at the end of the composite pipe reinforcement layer, and a female joint reinforcement layer material continuous with the composite pipe reinforcement layer is wound on the mandrel to form a female joint. Joints; the compound pipe short joint reinforcement layer material is wound on the composite pipe short joint inner lining layer to form a composite pipe short joint reinforcement layer, and the connection parts are processed at both ends of the composite pipe short joint reinforcement layer; two short joints are connected by a composite pipe Composite pipe with female couplings at the ends. It solves the problem that the metal joint is not corrosion-resistant in the prior art, and solves the problem that the connection strength in the prior art is lower than that of the composite pipe, and increases the connection strength and service life.

Description of drawings

Fig. 1 is a schematic structural diagram of a female joint provided by an embodiment of the present invention;

Fig. 2 is a structural schematic diagram of a composite pipe nipple provided by an embodiment of the present invention;

Fig. 3 is a structural schematic diagram of an anti-corrosion and high-pressure resistant composite pipe joint provided by an embodiment of the present invention;

Fig. 4 is a schematic structural diagram of a filament winding commutator provided by an embodiment of the present invention.

In the figure: 1. Inner lining layer of composite pipe; 2. Reinforcing layer of composite pipe; 3. Outer protective layer of composite pipe; 4. First sealing ring; 5. Female joint; 6. Internal thread; 8. Inner lining layer of composite pipe Flanging; 9. Composite pipe nipple; 10. Composite pipe nipple reinforcing layer; 11. External thread; 12. Composite pipe nipple inner lining; 13 is the second sealing ring.

Detailed ways

The present invention will be further described in detail below in conjunction with specific embodiments, which are explanations of the present invention rather than limitations.

As shown in Figures 1 to 3, the composite pipe includes a composite pipe inner lining 1, a composite pipe reinforcement layer 2 and an outer protective layer 3 of the composite pipe, and the composite pipe inner lining 1, the composite pipe reinforcement layer 2 and the outer protective layer of the composite pipe 3. Arranged concentrically from the inside to the outside, an anti-corrosion and high-pressure composite pipe joint provided by the embodiment of the present invention includes: a female joint 5 and a composite pipe nipple 9; the female joint 5 is located at the end of the composite pipe, and the composite The pipe reinforcement layer 2 is integrally formed, and the two ends of the composite pipe nipple 9 are respectively provided with connection parts, and the connection parts are connected with the female joint 5. Composite pipe. The female joint 5 is provided with an internal thread 6, and the connecting part is provided with an external thread 11, and the internal thread 6 and the external thread 11 are connected.

The composite pipe sub-joint 9 includes a composite pipe sub-joint lining layer 12 and a composite pipe sub-joint reinforcing layer 10, the composite pipe sub-joint reinforcing layer 10 is arranged on the outside of the composite pipe sub-joint lining layer 1, and the end of the composite pipe sub-joint lining layer 12 A flanging is provided at the end, and a flanging 8 of the inner lining layer of the composite pipe is provided at the end of the inner lining layer of the composite pipe 1 .

A first sealing ring 4 is arranged between the female joint 5 and the inner lining layer of the composite pipe, and a second sealing ring 13 is arranged between the short joint 9 of the composite pipe and the composite pipe.

The composite pipe reinforcement layer 2 is formed by winding the composite pipe inner liner 1 through the winding material, and the female joint 5 is formed by winding the winding material, and the winding material of the composite pipe reinforcement layer 2 and the winding material of the female joint 5 are continuous. The wrapping material of the female joint 5 includes wrapping fibers and thermosetting resin.

The production process of the female joint 5 is carried out synchronously and continuously with the production process of the composite pipe body. At the termination part of the composite pipe body, after the fibers wound with the composite pipe reinforcement layer 2 are combined with the thermosetting resin, the inner lining layer 1 of the composite pipe is composited. and the internal thread 6 mold are wound with a fiber winding commutator at a certain angle to a certain thickness and length, and after curing, the internal thread 6 mold is taken out, the female joint 5 and the internal thread 6 are manufactured, and the composite pipe nipple 9 is manufactured, that is, in The outside of the inner liner of the pup joint is wound with fiber and thermosetting resin compound, and after curing, the external thread 11 matching the internal thread 6 is processed at both ends of the pup joint reinforcement layer, the two ends of the inner liner of the pup joint are flanged, and the female joint 5 The second sealing ring 13 is added when the composite pipe nipple 9 is threadedly connected, and the two composite pipes with the female joint 5 are connected with a composite pipe nipple 9 to realize the connection between the composite pipes.

The material of the inner lining of the pup joint of the composite pipe is the same as that of the inner lining of the composite pipe, and the material of the inner lining is thermoplastic, preferably polyethylene, polypropylene, polyvinylidene fluoride, nylon, polystyrene, polyphenylene sulfide , Polyetheretherketone.

Both ends of the inner lining layer of the composite pipe pup joint adopt the flanging process to increase the sealing area between the inner lining layer and the sealing ring. The reinforcing layer of the composite pipe short joint is made of composite pipe body reinforcing layer material and thermosetting resin wound and compounded.

An embodiment of the present invention provides a connection method for an anti-corrosion and high-pressure resistant composite pipe joint, including:

Step S1, setting a female joint 5 mandrel at the end of the composite pipe reinforcement layer 2, winding the female joint 5 winding material continuous with the composite pipe reinforcement layer 2 on the mandrel to form the female joint 5;

Step S2, according to the size of the female joint 5 formed in step S1, process the connecting parts at both ends of the composite pipe pup joint 9;

Step S3, connecting two composite pipes with female joints 5 at the ends by short-circuiting the composite pipes, wherein the female joints 5 and the connecting parts are linked.

Wherein, in step S1, after winding the female joint 5 continuous with the composite pipe reinforcement layer 2 on the mandrel, and curing at 25-65°C for 8-36 hours, the mandrel is taken out to obtain a composite pipe integrated Female connector 5.

In step S2, after winding the composite pipe short joint reinforcing layer 10 material on the composite pipe short joint inner lining layer 12, curing is carried out at 45-85° C. for 5.5-8.5 hours.

The mandrel is a threaded mold, and the two ends of the short section 9 of the composite pipe are processed with threads.

Before step S1, a filament winding commutator is set outside the liner pipe, as shown in Fig. 4 . It also includes setting a first sealing ring 4 at the end of the inner lining layer 1 of the composite pipe.

Example 1

When the composite pipe is a glass fiber reinforced polyvinylidene fluoride composite pipe:

The inner lining layer 1 of the composite pipe is made of polyvinylidene fluoride, the reinforcing layer 2 of the composite pipe is directly wound with glass fibers, and the outer protective layer 3 of the composite pipe is coated with polyethylene. The 5th part of the female joint is wound with glass fiber continuous with the composite pipe reinforcement layer 2 and epoxy resin. The resin formula is 100 parts of 6101 epoxy, 12 parts of 304 polyester, and 17 parts of triethanolamine. 2 fluorine rubber O-rings, the inner side of the sealing ring is equipped with a filament winding commutator, the core mold is a tapered thread mold, the core mold is coaxially fixed with the inner lining layer 1 of the composite pipe, the mold is coated with a mold release agent, and the female joint 5 Curing at 55° C. for 24 hours, taking out the mold after curing, and the composite pipe with the female joint 5 is completed. The inner lining material of the composite pipe short section 9 is polyvinylidene fluoride, and the reinforcement layer 10 of the composite pipe short section is made of glass fiber and epoxy resin and then wound. The resin formula is 100 parts of 6101 epoxy, 12 parts of 304 polyester, and 17 parts of triethanolamine. After the winding is completed, cure at 80°C for 18 hours, process flanging at both ends of the inner liner, and process tapered threads matching the female joint 5 at both ends of the pup joint. A composite pipe with a female joint 5 is connected to the external thread 11 at one end of the pup joint, and a sealing ring is added when connecting, and another composite pipe with a female joint 5 is connected to the external thread 11 at the other end of the pup joint, and a sealing ring is added when connecting. Realize the entire pipeline connection. After the connection, a verification test was carried out, and the test content included a short-term hydraulic burst test and a long-term gas sealing test. The short-term water pressure burst pressure value is 65MPa, the pipe body part fails, and the joint connection does not fail. The gas pressure value of the long-term gas sealing test is 20MPa, and the pressure is maintained for 4 hours, and there is no leakage at the pipe body and the joint connection.

Example 2

When the composite pipe is aramid fiber reinforced nylon 11 composite pipe:

The inner lining layer 1 of the composite pipe is made of nylon 11, the reinforcing layer 2 of the composite pipe is directly wound with aramid fibers, and the outer protective layer is covered with polyethylene. The 5th part of the female joint is wound by compounding aramid fibers continuous with the reinforcement layer and epoxy resin. The resin formula is 100 parts of 6101 epoxy and 10 parts of 304 polyester. When winding, two fluororubbers are installed on the inner lining layer 1 of the composite pipe O-shaped sealing ring, a fiber winding commutator is installed inside the sealing ring, the core mold is a tapered thread mold, the core mold is coaxially fixed with the inner lining layer 1 of the composite pipe, the mold is coated with a release agent, and the female joint 5 is cured at 45°C After 48 hours, take out the mold after curing, and the composite pipe with the female joint 5 is completed. The inner lining material of the composite pipe nipple 9 is nylon 11, and the reinforced layer 10 of the composite pipe nipple is made of aramid fiber and epoxy resin and then wound. The resin formula is 100 parts of 6101 epoxy and 10 parts of 304 polyester. After winding, 85 Cure for 12 hours, process flanging at both ends of the inner liner 1 of the composite pipe, and process tapered threads matching the female joint 5 at both ends of the pup joint 9 of the composite pipe. A composite pipe with a female joint 5 is connected to the external thread 11 at one end of the short joint, and a sealing ring is added when connecting. The sealing ring is made of polytetrafluoroethylene, and another composite pipe with a female joint 5 is connected to the short joint 9 The external thread 11 at one end is connected, and a polytetrafluoroethylene sealing ring is added during the connection to realize the connection of the entire pipeline. After the connection, a verification test was carried out, and the test content included a short-term hydraulic burst test and a long-term gas sealing test. The short-term water pressure burst pressure value is 54MPa, the pipe body part fails, and the joint connection does not fail. The gas pressure value of the long-term gas sealing test is 15MPa, and the pressure is maintained for 4 hours, and the composite pipe body and joint joints have no leakage.

The specific embodiments cited in the present invention are only interpretations of the spirit of the invention, and those skilled in the technical field of the present invention may modify the described specific embodiments or replace them with similar methods without departing from the spirit of the present invention.

Claims (10)

1. a kind of anti-corrosion high voltage-resistant multiunit tube joint, which is characterized in that including female connector (5) and multiple tube pipe nipple (9)；It is described Female connector (5) is located at the end of multiple tube and multiple tube enhancement layer (2) is integrally formed, and the both ends of multiple tube pipe nipple (9) are set respectively It is equipped with interconnecting piece, the interconnecting piece and female connector (5) connection, in use, connecting the setting of two radicles by multiple tube pipe nipple (9) There is the multiple tube of female connector (5)；

Multiple tube enhancement layer (2) is wrapped on composite pipe lining layer (1) by reinforcement material and is molded, and the female connector (5) is logical Cross that reinforcement material is Wrapping formed, the reinforcement material of multiple tube enhancement layer (2) and the reinforcement material of female connector (5) are continuous 's.

2. a kind of anti-corrosion high voltage-resistant multiunit tube joint as described in claim 1, which is characterized in that on the female connector (5) It is provided with internal thread (6), external screw thread (11) is provided on the interconnecting piece, the internal thread (6) and external screw thread (11) sealing connect It connects, the thread rotary orientation on the interconnecting piece of multiple tube pipe nipple both ends is opposite.

3. a kind of anti-corrosion high voltage-resistant multiunit tube joint as described in claim 1, which is characterized in that the multiple tube pipe nipple (9) include multiple tube pipe nipple liner layer (12) and multiple tube pipe nipple enhancement layer (10), multiple tube pipe nipple enhancement layer (10), which is arranged, to exist The outside of multiple tube pipe nipple liner layer (12), multiple tube pipe nipple liner layer (12) end set have flange.

4. a kind of anti-corrosion high voltage-resistant multiunit tube joint as described in claim 1, which is characterized in that the female connector (5) and The first sealing ring (4) is provided between composite pipe lining layer (1), the multiple tube pipe nipple (9) is provided between multiple tube Two sealing rings (13).

5. a kind of anti-corrosion high voltage-resistant multiunit tube joint as claimed in claim 4, which is characterized in that the first sealing ring (4) is set There are two setting, and it is O-ring seal.

6. a kind of anti-corrosion high voltage-resistant multiunit tube joint as described in claim 1, which is characterized in that female connector reinforcement material Including winding fiber and thermosetting resin.

7. a kind of connection method of anti-corrosion high voltage-resistant multiunit tube joint, which is characterized in that including：

Step S1, in multiple tube enhancement layer (2) end set female connector core model, winding and multiple tube enhancement layer (2) on core model Continuous female connector reinforcement material, forms female connector (5)；

Step S2, the coiled composite tube pipe nipple reinforcement material on multiple tube pipe nipple liner layer (12) form multiple tube pipe nipple and increase Strong layer (10) processes interconnecting piece at the both ends of multiple tube pipe nipple enhancement layer (10)；

Step S3 passes through multiple tube pipe nipple and connects multiple tube of two ends with female connector (5), wherein female connector (5) and company Socket part connects.

8. a kind of connection method of anti-corrosion high voltage-resistant multiunit tube joint as claimed in claim 7, which is characterized in that step S1 Before, fiber outside internal lining pipe is set and winds commutator；

In step S1, on core model after the continuous female connector reinforcement material of winding and multiple tube enhancement layer (2), and 25~65 After curing 8~36 hours at DEG C, core model is taken out, is obtained and the female connector of multiple tube one (5).

9. a kind of connection method of anti-corrosion high voltage-resistant multiunit tube joint as claimed in claim 7, which is characterized in that step S2 In, on multiple tube pipe nipple liner layer (12) after coiled composite tube pipe nipple reinforcement material, at 45~85 DEG C cure 5.5~ 8.5 hour.

10. a kind of connection method of anti-corrosion high voltage-resistant multiunit tube joint as claimed in claim 7, which is characterized in that described Core model is threaded mold, and the both ends of multiple tube pipe nipple (9) are threaded.