Glass fiber belt reinforced flexible composite pipeline connecting pipe fitting

Abstract

The utility model discloses a glass fiber belt reinforced flexible composite pipeline connecting pipe fitting, and relates to the technical field of glass fiber belt reinforced RTP pipe connecting joints, a plurality of longitudinal grooves are uniformly distributed on the inner diameter annular surface at the inlet end of an outer sleeve along the circumference, the length of the longitudinal grooves does not exceed the radial sealing position, and the cross section of each longitudinal groove is triangular, semicircular or elliptical. Meanwhile, a thin plastic sleeve structure is additionally arranged in the area, the thin plastic sleeve has certain strength and certain stretching ductility, and after the pipe is installed, part of materials of the thin plastic sleeve are squeezed into the longitudinal grooves evenly distributed in the circumferential direction of the inlet end of the outer sleeve to form a mutual embedding and locking structure; the structure can effectively prevent relative rotation between pipes and pipe fittings, the leakage accident caused by relative rotation is avoided, meanwhile, the thin plastic sleeve well disperses stress concentration at the inlet end of the original pipe fitting, and the problem that the pipes are fractured in the circumferential direction along the inlet end of the pipe fitting in a high-pressure test is thoroughly solved.

Description

Technical Field

[0001] The utility model relates to the technical field of connecting joints of glass fiber belt reinforced RTP pipes, and in particular to a connecting fitting for glass fiber belt reinforced flexible composite pipes. Background Technique

[0002] In the initial stage of the application of glass fiber belt reinforced flexible composite pipe products, the developed metal connecting joints are prone to the phenomenon that the RTP pipe and the metal pipe fitting rotate relative to each other during the pipeline laying process. Once relative rotation occurs, the bonding force between the pipe and the pipe fitting will be relatively weakened, and the pipe and the pipe fitting are prone to come off during the high-pressure operation of the pipeline, resulting in leakage accidents. Another problem is that during the high-pressure test after the pipe is inserted into the pipe fitting, the pipe breaks along the circumferential line at the end of the outer sleeve of the pipe fitting. To solve the above two problems, through rigorous technical analysis and a large number of improvement experiments, we have verified the structure of the metal connecting fitting for the glass fiber belt reinforced composite pipe, which has well solved the problem of relative rotation between the pipe and the pipe fitting, and at the same time has well solved the problem that the pipe is prone to circumferential fracture at the end due to stress concentration at the inlet end of the pipe fitting, and significantly reduced the leakage phenomenon at the connection between the pipe and the pipe fitting.

[0003] Therefore, a connecting fitting for glass fiber belt reinforced flexible composite pipes is provided to solve the above problems. Summary of the Utility Model

[0004] The purpose of the utility model is to provide a connecting fitting for glass fiber belt reinforced flexible composite pipes, which has a guiding function and excellent performance, can resist the huge axial pull-off force generated inside and outside the pipe, and has a service life longer than that of the glass fiber belt RTP pipe.

[0005] To achieve the above purpose, the utility model provides a connecting fitting for glass fiber belt reinforced flexible composite pipes, which includes an outer sleeve arranged outside the first inner tube and the second inner tube. An oil-joint type connecting nut is arranged outside the connection of the first inner tube and the second inner tube. A groove is arranged on the first inner tube, and a protrusion is arranged on the second inner tube. The first inner tube and the second inner tube are connected by matching the groove and the protrusion. One end of the first inner tube connected to the oil-joint type connecting nut is set as a threaded head, and one end of the second inner tube connected to the oil-joint type connecting nut is set as a T-shaped flat head structure.

[0006] Preferably, the end faces between the first inner tube and the second inner tube are hermetically connected.

[0007] Preferably, a pressure balance hole is arranged on the outer sleeve, and a thin plastic sleeve is arranged at one end of the outer sleeve away from the oil-joint type connecting nut. The thin plastic sleeve is nested and linked with the outer sleeve.

[0008] Preferably, tooth-shaped structures are provided on the outer walls of the ends of the first embedded pipe and the second embedded pipe away from the oil-joint type connection nut and on the inner wall of the outer sleeve, and the first embedded pipe and the second embedded pipe are fixedly connected to the outer sleeve by welding.

[0009] Preferably, the oil-joint type connection nut includes an outer wall layer and an inner wall layer. A plurality of outer wall grooves are provided on the outer wall layer, and the outer wall grooves are evenly distributed in the circumferential direction. The inner wall layer is provided in two parts. The part of the inner wall layer connected to the first embedded pipe is provided with a thread structure, and the part of the inner wall layer connected to the second embedded pipe is provided with a mortise and tenon structure. The inner wall layer is hermetically connected to the first embedded pipe by threads, and the inner wall layer is hermetically connected to the second embedded pipe by a mortise and tenon.

[0010] Preferably, a plurality of longitudinal grooves are provided between the outer sleeve and the thin plastic sleeve. The longitudinal grooves are evenly distributed in the circumferential direction, and the cross section of the longitudinal groove is triangular, circular or elliptical.

[0011] Preferably, two radial sealing rings are provided at the entrances of the first embedded pipe and the second embedded pipe. The radial sealing rings are O-rings, and the depth of the longitudinal groove does not exceed the set depth of the O-ring.

[0012] Therefore, a glass fiber belt-reinforced flexible composite pipe connecting fitting with the above structure has the following beneficial effects:

[0013] (1) Multiple circles of tooth-shaped structures with specific sizes and angles not only ensure a guiding effect during installation but also can resist the huge axial pulling-off forces generated inside and outside the pipe after installation by a special hydraulic device.

[0014] (2) Double radial seals are provided near the entrances of the embedded pipes, and end-face seals are used for both the flat head and the threaded head end faces to improve the overall sealing performance of the glass fiber belt-reinforced flexible composite pipe connecting fitting.

[0015] (3) The oil-joint type nut can firmly connect the pipe fittings and at the same time provide a pressing force to the sealing end face to ensure sealing.

[0016] The technical solution of the present invention will be further described in detail below with reference to the drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] Figure 1 is a sectional view of a glass fiber belt-reinforced flexible composite pipe connecting fitting of the present invention;

[0018] Figure 2 is a plan view of a glass fiber belt-reinforced flexible composite pipe connecting fitting of the present invention;

[0019] Figure 3 This is a structural diagram of a connecting fitting for a fiberglass tape-reinforced flexible composite pipe according to the present utility model;

[0020] Figure 4 This is a side sectional view of a connecting fitting for a fiberglass tape-reinforced flexible composite pipe according to the present utility model.

[0021] Wherein: 1. Inner embedded pipe one; 101. Groove; 2. Inner embedded pipe two; 201. Protrusion; 3. Outer sleeve; 301. Pressure balance hole; 4. Union type connection nut; 401. Outer wall layer; 402. Inner wall layer; 403. Thread structure; 404. Tenon and mortise structure; 405. Outer wall groove; 5. Thread head; 6. T-shaped flat head structure; 7. Tooth profile structure; 8. Longitudinal groove; 9. Thin plastic sleeve; 10. O-ring. Specific embodiments

[0022] The technical solutions of the present utility model will be further described below with reference to the accompanying drawings and embodiments.

[0023] Unless otherwise defined, the technical terms or scientific terms used in the present utility model shall have the ordinary meanings understood by those of ordinary skill in the field to which the present utility model belongs. The "first", "second" and similar terms used in the present utility model do not denote any order, quantity or importance, but are only used to distinguish different components. The terms such as "comprising" or "including" mean that the elements or objects appearing before this term cover the elements or objects listed after this term and their equivalents, without excluding other elements or objects. The terms such as "connected" or "coupled" are not limited to physical or mechanical connections, but may include electrical connections, whether direct or indirect. The terms such as "upper", "lower", "left" and "right" are only used to represent relative positional relationships, and when the absolute position of the object being described changes, the relative positional relationship may also change accordingly.

[0024] As Figure 1 shown, the present utility model provides a connecting fitting for a fiberglass tape-reinforced flexible composite pipe, including an outer sleeve 3 arranged outside the inner embedded pipe one 1 and the inner embedded pipe two 2. A groove 101 is arranged on the inner embedded pipe one 1, and a protrusion 201 is arranged on the inner embedded pipe two 2. The inner embedded pipe one 1 and the inner embedded pipe two 2 are connected by matching the groove 101 and the protrusion 201. The end faces of the inner embedded pipe one 1 and the inner embedded pipe two 2 are hermetically connected. An outer sleeve 3 is arranged outside the connection part of the inner embedded pipe one 1 and the inner embedded pipe two 2. One end of the inner embedded pipe one 1 connected to the union type connection nut 4 is set as a thread head 5, and one end of the inner embedded pipe two 2 connected to the union type connection nut 4 is set as a T-shaped flat head structure 6. One end of the outer sleeve 3 far from the union type connection nut 4 is provided with a thin plastic sleeve 9. The thin plastic sleeve 9 is nested and linked with the outer sleeve 3. The thin plastic sleeve 9 has both a certain strength and a certain tensile ductility;

[0025] The oil-joint type connecting nut 4 includes an outer wall layer 401 and an inner wall layer 402. The inner wall layer 402 is set in two parts. The part of the inner wall layer 402 connected to the first embedded pipe 1 is set as a threaded structure 403, and the part of the inner wall layer 402 connected to the second embedded pipe 2 is set as a mortise and tenon structure 404. The inner wall layer 402 is connected to the first embedded pipe 1 through threaded sealing, and the inner wall layer 402 is connected to the second embedded pipe 2 through mortise and tenon sealing. As Figure 3 shown, a plurality of outer wall grooves 405 are provided on the outer wall layer 401, and the outer wall grooves 405 are evenly distributed circumferentially;

[0026] As Figure 2 shown, a pressure balance hole 301 is provided on the outer sleeve 3;

[0027] Tooth-shaped structures 7 are provided on the outer sides of the ends of the first embedded pipe 1 and the second embedded pipe 2 far from the oil-joint type connecting nut 4 and on the inner wall of the outer sleeve 3. The first embedded pipe 1 and the second embedded pipe 2 are fixedly connected to the outer sleeve 3. As Figure 4 shown, a plurality of longitudinal grooves 8 are provided between the outer sleeve 3 and the thin plastic sleeve 9. The longitudinal grooves 8 are evenly distributed circumferentially. The cross-section of the longitudinal grooves 8 is set as a triangle, a circle or an ellipse. Two end face sealing rings are provided at the entrance of the first embedded pipe 1 and the entrance of the second embedded pipe 2. The radial sealing ring is set as an O-ring 10. The depth of the longitudinal grooves 8 does not exceed the set depth of the O-ring 10.

[0028] Embodiment

[0029] Use special hydraulic equipment to install the pipe fittings onto the RTP pipe. The tooth-shaped structure 7 is embedded in the outer protective layer and the inner lining layer of the pipe. The tooth-shaped structure 7 can enhance the bonding force between the outer sleeve 3, the first embedded pipe 1 and the second embedded pipe 2 and the pipe, and will generate a huge pressure to squeeze the inner and outer walls of the pipe. In this case, stress concentration will occur in some parts. This stress concentration will be transmitted to the fiberglass belt reinforcement layer in the middle of the pipe. The fiberglass belt has excellent high tensile strength, but is prone to shear brittle fracture when the stress is large. At the entrance end of the outer sleeve, several longitudinal grooves 8 are evenly distributed along the circumference on the inner diameter circumferential surface. At the same time, a thin plastic sleeve 9 is added in this area. After the pipe installation is completed, part of its material is squeezed into the longitudinally grooved 8 evenly distributed circumferentially at the entrance end of the outer sleeve 3, forming a structure of mutual embedding and locking. This structure can effectively prevent the relative rotation between the pipe and the pipe fittings, solve the leakage accident caused by the relative rotation, and at the same time the thin plastic sleeve 9 well disperses the original stress concentration at the entrance end of the pipe fittings, completely solves the problem of circumferential fracture along the entrance end of the pipe fittings in the high-pressure test of the pipe, so that the long-term high-pressure resistance performance of the RTP pipe is not damaged or weakened, solves the problem that the connection node is the weak point of the pipeline, and the joint part is integrated with the pipe, thus ensuring the stable and safe operation of the whole laid pipeline.

[0030] Therefore, the glass fiber belt reinforced flexible composite pipe connecting fitting with the above structure adopted by the present utility model has a guiding effect and excellent performance, can resist the huge axial pulling-off force generated inside and outside the pipe, and has a service life longer than that of the glass fiber belt RTP pipe.

[0031] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present utility model and not to limit them. Although the present utility model has been described in detail with reference to the preferred embodiments, those of ordinary skill in the art should understand that they can still modify or equivalently replace the technical solutions of the present utility model, and these modifications or equivalent replacements cannot make the modified technical solutions deviate from the spirit and scope of the technical solutions of the present utility model.

Claims

1. A connecting fitting for a glass fiber tape reinforced flexible composite pipe, characterized in that: It includes a jacket pipe arranged outside the inner pipe one and the inner pipe two. An oil union type connection nut is arranged outside the connection of the inner pipe one and the inner pipe two. A groove is arranged on the inner pipe one, and a protrusion is arranged on the inner pipe two. The inner pipe one and the inner pipe two are connected in a matching manner through the groove and the protrusion. One end of the inner pipe one connected to the oil union type connection nut is set as a threaded head, and one end of the inner pipe two connected to the oil union type connection nut is set as a T-shaped flat head structure.

2. The fiberglass tape-reinforced flexible composite pipe connection fitting according to claim 1, characterized in that: The end faces between the inner pipe one and the inner pipe two are hermetically connected.

3. The glass fiber tape reinforced flexible composite pipe connecting fitting according to claim 1, characterized in that: Pressure balance holes are arranged on the jacket pipe. A thin plastic sleeve is arranged at one end of the jacket pipe far from the oil union type connection nut. The thin plastic sleeve is nested and linked with the jacket pipe.

4. The glass fiber belt reinforced flexible composite pipe connecting fitting according to claim 1, characterized in that: Threaded structures are arranged on the outer walls of the ends of the inner pipe one and the inner pipe two far from the oil union type connection nut and on the inner wall of the jacket pipe. The inner pipe one and the inner pipe two are fixedly connected to the jacket pipe.

5. The glass fiber belt reinforced flexible composite pipe connecting fitting according to claim 1, characterized in that: The oil union type connection nut includes an outer wall layer and an inner wall layer. A number of outer wall grooves are arranged on the outer wall layer, and the outer wall grooves are evenly distributed in the circumferential direction. The inner wall layer is arranged in two parts. The part of the inner wall layer connected to the inner pipe one is set as a threaded structure, and the part of the inner wall layer connected to the inner pipe two is set as a mortise and tenon structure. The inner wall layer is hermetically connected to the inner pipe one through threads, and the inner wall layer is hermetically connected to the inner pipe two through a mortise and tenon.

6. The glass fiber belt reinforced flexible composite pipe connecting fitting according to claim 3, characterized in that: A number of longitudinal grooves are arranged between the jacket pipe and the thin plastic sleeve, and the longitudinal grooves are evenly distributed in the circumferential direction. The cross-section of the longitudinal groove is set as a triangle, a circle or an ellipse.

7. A glass fiber tape reinforced flexible composite pipe connecting fitting according to claim 6, characterized in that: Two radial sealing rings are arranged at the entrances of both the inner pipe one and the inner pipe two. The radial sealing rings are set as O-rings. The depth of the longitudinal groove does not exceed the set depth of the O-ring.

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