Steel-plastic composite insulating flange joint for pipeline lining
By adopting a steel-plastic composite structure and insulation design in the flange joint, the risk of electric sparks in traditional flange joints when conveying corrosive liquids is solved, achieving electrical isolation and sealing effects, and improving safety and service life.
Patent Information
- Authority / Receiving Office
- CN · China
- Patent Type
- Utility models(China)
- Current Assignee / Owner
- SHANDONG KELINRUIER PIPELINE ENG
- Filing Date
- 2025-06-06
- Publication Date
- 2026-05-01
AI Technical Summary
Traditional flange joints have stray current flow caused by potential difference when conveying corrosive liquids, which may lead to the risk of oil and gas explosion caused by electric sparks, and cannot meet the technical requirements for anti-static insulation performance.
The steel-plastic composite structure is adopted, with PE pipes in the inner layer and steel pipes in the outer layer. Insulating gaskets and insulating bushings are installed between the flanges, and combined with insulating nuts and fastening bolts, an electrical isolation effect is formed.
It achieves electrical isolation when conveying corrosive media, avoids the generation of electric sparks, ensures sealing performance and service life, and meets the requirements for antistatic insulation performance.
Smart Images
Figure CN224188187U_ABST
Abstract
Description
A steel-plastic composite insulated flange joint for pipe lining Technical Field
[0001] This utility model relates to the field of pipeline lining technology, specifically to a steel-plastic composite insulating flange joint for pipeline lining. Background Technology
[0002] Flange joints, generally used for connecting steel pipes, are first welded and fixed to the two pipe ends. A metal retaining ring is then installed between the two flanges. The flanges and the metal retaining ring are then tightened together with bolts to form a flange joint with good sealing performance, thus completing the connection between the pipes. This type of flange joint is widely used in pipeline networks that transport ordinary flowing media.
[0003] When used for transporting crude oil and corrosive liquids, corrosion and insulation issues between pipelines and between pipelines and equipment must be considered. Traditional flange joints cannot interrupt stray currents caused by the potential difference between pipelines and equipment. The electric sparks generated by these stray currents could potentially ignite and explode oil and gas, leading to major accidents. This poses a significant hidden danger to oil pipelines. Therefore, existing flange joints must be structurally improved to ensure their electrical performance meets the anti-static insulation requirements specified in relevant standards. Only in this way can fire and explosion accidents caused by non-compliant flange connections be fundamentally prevented. Summary of the Invention
[0004] The purpose of this utility model is to provide a steel-plastic composite insulating flange joint for pipe lining, so as to solve the problem of the inconvenience of flange joints in use mentioned in the background art.
[0005] To achieve the above objectives, this utility model provides the following technical solution: a steel-plastic composite insulating flange joint for pipe lining, comprising an outer steel pipe, an inner PE pipe, a left steel flange, and a right steel flange. The inner PE pipe is disposed inside the outer steel pipe. A left steel flange is disposed at one end of the outer steel pipe, and a right steel flange is disposed at the other end of the outer steel pipe. An insulating gasket is disposed between the right steel flange and the left steel flange. Through holes are provided between the left steel flange, the right steel flange, and the insulating gasket, and the through holes are symmetrically distributed in the left steel flange, the right steel flange, and the insulating gasket.
[0006] Preferably, an insulating bushing is provided inside the through hole, and a knock-through bolt passes through the left steel flange, the right steel flange, and the insulating gasket.
[0007] Preferably, an insulating nut and flat washer are fitted onto the end of each of the counterbolts near the left and right steel flanges.
[0008] Preferably, the insulating nut washer is symmetrically distributed at both ends of the knock-off bolt, and a fastening bolt is connected to the end of the knock-off bolt closest to the insulating nut washer.
[0009] Preferably, the outer steel pipe is provided with a left PE flange that connects to the inner PE pipe at one end near the left steel flange.
[0010] Preferably, another outer steel pipe is provided with a right PE flange at one end near the right steel flange, which is connected to the inner PE pipe.
[0011] Compared with the prior art, the beneficial effects of this utility model are:
[0012] 1. The steel-plastic composite insulating flange joint used for pipeline lining has an inner PE pipe with a plastic corrosion-resistant structure and an outer steel pipe with a steel pipe structure. This ensures that the two fit tightly together after assembly, which can guarantee the pressure level required for medium transportation and avoid the impact of corrosive medium transportation on the pipeline life.
[0013] 2. The steel-plastic composite insulating flange joint used for pipe lining uses FR4 glass fiber insulating material flange gaskets for insulating nuts and flat gaskets. It has the advantages of high hardness, good insulation performance and easy processing. When used in conjunction with insulating bushings and insulating flat gaskets, it can fully achieve the effect of electrical isolation and insulation.
[0014] 3. The steel-plastic composite insulating flange joint used for pipe lining connects the inner PE pipe to the right PE flange via the left PE flange. This ensures that the two are tightly squeezed together after connection, and while guaranteeing sealing performance, it avoids excessive squeezing between the left and right PE flanges, which could affect service life. Attached Figure Description
[0015] Figure 1 is a three-dimensional structural diagram of the present invention;
[0016] Figure 2 is a three-dimensional cross-sectional view of the present invention;
[0017] Figure 3 is a schematic diagram of the misaligned three-dimensional structure of the two outer steel pipes of this utility model;
[0018] Figure 4 is a three-dimensional explosion diagram of this utility model.
[0019] In the diagram: 1. Outer steel pipe; 2. Inner PE pipe; 3. Left steel flange; 4. Right steel flange; 5. Insulating gasket; 6. Through hole; 7. Insulating bushing; 8. Double-hammer bolt; 9. Insulating nut and flat washer; 10. Fastening bolt; 11. Left PE flange; 12. Right PE flange. Detailed Implementation
[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.
[0021] Please refer to Figures 1-4. This utility model provides a technical solution: a steel-plastic composite insulating flange joint for pipe lining, including an outer steel pipe 1, an inner PE pipe 2, a left steel flange 3, and a right steel flange 4. The inner PE pipe 2 is arranged inside the outer steel pipe 1. The left steel flange 3 is arranged at one end of the outer steel pipe 1, and the right steel flange 4 is arranged at the other end of the outer steel pipe 1. An insulating gasket 5 is arranged between the right steel flange 4 and the left steel flange 3. Through holes 6 are opened between the left steel flange 3, the right steel flange 4, and the insulating gasket 5, and the through holes 6 are symmetrically distributed in the left steel flange 3, the right steel flange 4, and the insulating gasket 5.
[0022] This is a steel-plastic composite insulating flange joint used for pipe lining. The inner PE pipe 2 adopts a plastic corrosion-resistant structure, which can avoid the impact of corrosive media transportation on the pipe life.
[0023] The inner PE pipe 2 adopts a plastic corrosion-resistant structure, and the outer steel pipe 1 adopts a steel pipe structure. This ensures that the two fit tightly together after assembly, which can guarantee the pressure level required for medium transportation and avoid the impact of corrosive medium transportation on the pipe's lifespan.
[0024] In Figures 3 and 4, an insulating bushing 7 is provided inside the through hole 6. A knock-through bolt 8 passes through the left steel flange 3, the right steel flange 4, and the insulating gasket 5. An insulating nut flat washer 9 is fitted to one end of the knock-through bolt 8 near the left steel flange 3 and the right steel flange 4. The insulating nut flat washer 9 is symmetrically distributed at both ends of the knock-through bolt 8. A fastening bolt 10 is connected to one end of the knock-through bolt 8 near the insulating nut flat washer 9.
[0025] This steel-plastic composite insulating flange joint for pipe lining, through the setting of insulating nut flat washer 9, can make the fastening bolt 10 more stable during use.
[0026] The insulating nut flat washer 9 uses FR4 glass fiber insulating material flange gasket, which has the advantages of high hardness, good insulation performance and easy processing. When used in conjunction with the insulating bushing 7 and the insulating flat washer, it can fully achieve the effect of electrical isolation and insulation.
[0027] In Figures 3 and 4, the outer steel pipe 1 is provided with a left PE flange 11 connected to the inner PE pipe 2 at one end near the left steel flange 3, and the other outer steel pipe 1 is provided with a right PE flange 12 connected to the inner PE pipe 2 at one end near the right steel flange 4.
[0028] This steel-plastic composite insulating flange joint for pipe lining achieves a good sealing effect through the cooperation of the left PE flange 11, the right PE flange 12 and the insulating gasket 5.
[0029] The inner PE pipe 2 is connected to the left PE flange 11 and the right PE flange 12 through the left PE flange 11, so that the two are tightly squeezed together after the connection. At the same time, the outer diameter of the left PE flange 11 and the right PE flange 12 is smaller than the inner diameter of the insulating gasket 5, so that after compression, the edges of the two are squeezed together. Meanwhile, the high density, high strength and compression resistance of the insulating gasket 5 play a limiting role, ensuring the sealing performance while avoiding excessive compression of the left PE flange 11 and the right PE flange 12, which would affect the service life.
[0030] In summary, flange joints generally used for steel pipe connections are first welded and fixed to the two pipe ends. A metal retaining ring is then installed between the two flanges. The flanges and the metal retaining ring are then tightened together with the bolts 8 to form a flange joint with good sealing performance. The inner PE pipe 2 is connected to the right PE flange 12 through the left PE flange 11, so that the two are tightly squeezed together after connection. While ensuring sealing performance, excessive compression between the left PE flange 11 and the right PE flange 12 is avoided, which would affect the service life. The contents not described in detail in this specification are existing technologies known to those skilled in the art.
[0031] Although the present invention has been described in detail with reference to the foregoing embodiments, those skilled in the art can still modify the technical solutions described in the foregoing embodiments or make equivalent substitutions for some of the technical features. Any modifications, equivalent substitutions, improvements, etc., made within the spirit and principles of the present invention should be included within the protection scope of the present invention.
Claims
1. A steel-plastic composite insulating flange joint for pipe lining, comprising an outer steel pipe (1), an inner PE pipe (2), a left steel flange (3), and a right steel flange (4), characterized in that: The outer steel pipe (1) is provided with an inner PE pipe (2). One end of the outer steel pipe (1) is provided with a left steel flange (3), and the other end of the outer steel pipe (1) is provided with a right steel flange (4). An insulating gasket (5) is provided between the right steel flange (4) and the left steel flange (3). Through holes (6) are provided between the left steel flange (3), the right steel flange (4), and the insulating gasket (5), and the through holes (6) are symmetrically distributed in the left steel flange (3), the right steel flange (4), and the insulating gasket (5).
2. A steel-plastic composite insulating flange joint for pipe lining according to claim 1, characterized in that: An insulating bushing (7) is provided inside the through hole (6), and a knock bolt (8) passes through the left steel flange (3), the right steel flange (4), and the insulating gasket (5).
3. A steel-plastic composite insulating flange joint for pipe lining according to claim 2, characterized in that: The end of the counterbolt (8) near the left steel flange (3) and the right steel flange (4) is fitted with an insulating nut washer (9).
4. A steel-plastic composite insulating flange joint for pipe lining according to claim 3, characterized in that: The insulating nut washer (9) is symmetrically distributed at both ends of the knock-knock bolt (8), and the knock-knock bolt (8) is connected to a fastening bolt (10) at the end near the insulating nut washer (9).
5. A steel-plastic composite insulating flange joint for pipe lining according to claim 1, characterized in that: The outer steel pipe (1) is provided with a left PE flange (11) connected to the inner PE pipe (2) at one end near the left steel flange (3).
6. A steel-plastic composite insulating flange joint for pipe lining according to claim 1, characterized in that: Another outer steel pipe (1) is provided with a right PE flange (12) connected to the inner PE pipe (2) at one end near the right steel flange (4).