Sea pipe stand pipe and expansion bend inner surface cleaning system

Abstract

The utility model discloses an inner surface cleaning system for a subsea pipe stand pipe and an expansion bend. The inner surface cleaning system comprises a sand mixing unit, an injection unit and a flowback unit. The sand mixing unit comprises a liquid preparation tank, a functional assembly and a high-pressure manifold which are sequentially communicated through a pipeline; the functional assembly comprises a plunger pump and a sand mixing pump which are connected in parallel, and a sand adding device is arranged at an inlet above the sand mixing pump; the injection unit comprises a flexible pipe roller, a clamping device and a tool string, and the inlet end of the flexible pipe roller is connected with the outlet of the high-pressure manifold; a flexible pipe from the flexible pipe roller is introduced into the upper end of the clamp holder, and the lower end of the clamp holder is connected with a tool string; the tool string is injected into the stand pipe from the inlet end of the stand pipe; and the flowback unit comprises a sand setting tank and a centrifugal pump which are communicated with each other through a pipeline. By means of the subsea pipeline cleaning device, scale and oil-containing surfaces on the inner surfaces of a subsea pipeline vertical pipe and an expansion bend can be cleaned, under-scale corrosion and microbial corrosion are relieved, the influence of scaling on conveying is eliminated, the conveying efficiency is improved, and the completeness of a subsea pipeline is guaranteed.

Description

Technical Field

[0001] The utility model belongs to the technical field of offshore oil and gas field development, and in particular relates to a system for cleaning the inner surface of a sea pipe riser and an expansion bend. Background Art

[0002] Submarine pipelines are an important way to transport oil and gas. The integrity and long-term operation of submarine pipelines are important links in ensuring my country's energy security. Submarine pipelines are usually buried on the seabed, but when they are close to oil production platforms, they will be connected to the oil production platforms through risers. The risers and pipelines buried on the seabed are connected by expansion bends. Riser pipes and expansion bends are special structures. In a corrosive environment, the corrosion caused by scouring and bacteria is more serious than that of flat pipe sections. The existing technology is to replace risers and expansion bends whose corrosion margin exceeds the standard. The replacement of risers and expansion bends not only requires high engineering costs, but also increases the downtime of the oil field, and cannot guarantee the long-term operation of the oil field. Therefore, it is urgent to establish a surface cleaning system for risers and expansion bends to remove surface scale and corrosion products and reduce bacterial corrosion. Utility Model Content

[0003] The utility model is proposed to solve the problems existing in the prior art, and its purpose is to provide a system for cleaning the inner surface of a sea pipe riser and an expansion bend.

[0004] The utility model is realized by the following technical solutions:

[0005] A system for cleaning the inner surface of a sea pipe riser and an expansion bend comprises a sand mixing unit, an injection unit and a flowback unit; the sand mixing unit comprises a liquid distribution tank, a functional component and a high-pressure manifold which are sequentially connected through pipelines; the functional component comprises a plunger pump and a sand mixing pump which are connected in parallel, a sand feeder is arranged at the upper inlet of the sand mixing pump, and the sand feeder serves as an input of solid materials; the injection unit comprises a flexible tube drum, a clamp and a tool string, the inlet end of the flexible tube drum is connected to the outlet of the high-pressure manifold; the upper end of the clamp introduces the flexible tube from the flexible tube drum through an invertor, and the lower end of the clamp is connected to the tool string through a guide; the tool string is injected into the riser from the inlet end of the riser; the flowback unit comprises a sand settling tank and a centrifugal pump which are mutually connected through pipelines; the inlet of the sand settling tank is connected to the outlet of the riser.

[0006] In the above technical solution, the flexible tube drum connects the water source and the power supply to the flexible tube through the slip ring and the rotary joint; the flexible tube is a multi-layer composite structure, in which the communication line and the power circuit are built-in;

[0007] In the above technical solution, the clamp is a hydraulic system driving a crawler structure to inject the flexible tube into the pipeline, and the injection depth is calculated by a counter.

[0008] In the above technical solution, the tool string is a rotating structure.

[0009] In the above technical solution, the liquid outlet of the centrifugal pump is connected to the inlet of the liquid distribution tank.

[0010] The beneficial effects of the utility model are:

[0011] The utility model provides a system for cleaning the inner surface of a sea pipe riser and an expansion bend, which realizes the inner surface treatment of the pipeline after the tool string passes through multiple right-angle elbows, realizes the ability to clean the inner wall of the pipeline at a fixed point, and based on experimental research, analyzes the oil-bearing layer on the inner wall of the oil and gas pipeline, adds corresponding agents according to actual needs, and verifies the detection method of the oil-bearing surface; the structural design is reasonable and worthy of popularization and use. Through the implementation of the utility model, the scale and oil-bearing surface on the inner surface of the sea pipe riser and the expansion bend can be cleaned, the under-scale corrosion and microbial corrosion are reduced, the influence of scaling on transportation is eliminated, the transportation efficiency is improved, and the integrity of the sea pipe is better guaranteed. BRIEF DESCRIPTION OF THE DRAWINGS

[0012] Figure 1 It is a structural schematic diagram of the utility model.

[0013] in:

[0014] 1. Sand mixing unit;

[0015] 11. Liquid dispensing tank; 12. Plunger pump; 13. Sand mixing pump; 14. Sand feeder; 15. High-pressure manifold;

[0016] 2. Injection unit;

[0017] 21. Flexible tube drum; 22. Clamp; 23. Tool string; 24. No. Ⅰ guide; 25. No. Ⅱ guide;

[0018] 3. Flowback unit;

[0019] 31. Sand settling tank; 32. Centrifugal pump

[0020] 4. Vertical pipe.

[0021] For ordinary technicians in this field, other relevant drawings can be obtained based on the above drawings without any creative work. DETAILED DESCRIPTION

[0022] In order to enable those skilled in the art to better understand the technical solution of the present utility model, the technical solution of the present utility model will be further described below in conjunction with the accompanying drawings and through specific implementation methods.

[0023] like Figure 1As shown, a system for cleaning the inner surface of a subsea pipeline riser and an expansion bend comprises a sand mixing unit 1, an injection unit 2 and a flowback unit 3;

[0024] The sand mixing unit 1 comprises a liquid dispensing tank 11, a functional component and a high-pressure manifold 15 which are sequentially connected through pipelines; the functional component comprises a plunger pump 12 and a sand mixing pump 14 which are connected in parallel, and a sand feeder 13 is arranged at the upper inlet of the sand mixing pump 14, and the sand feeder 13 serves as the input of solid materials;

[0025] The high-pressure manifold 15 includes a plurality of inlet high-pressure pipes and a plurality of outlet high-pressure pipes, the inlet high-pressure pipes and the outlet high-pressure pipes are connected by a pump, one end of the inlet high-pressure pipe is connected to the outlet of the plunger pump 12 and the outlet of the sand mixing pump 14, and one end of the outlet high-pressure pipe is connected to the flexible pipe of the flexible pipe drum 21;

[0026] Specifically, the outlet of the liquid dispensing tank 1 is connected to the inlet of the plunger pump 12 and the inlet of the sand mixing pump 14 through pipelines, and the outlet of the plunger pump 12 and the outlet of the sand mixing pump 14 are connected to the inlet of the high-pressure manifold 15 through pipelines;

[0027] The injection unit 2 includes a flexible tube drum 21, a clamp 22 and a tool string 23, and the inlet end of the flexible tube of the flexible tube drum 21 is connected to the outlet of the high-pressure manifold 15;

[0028] The flexible tube drum 21 includes a drum frame and a flexible tube wound on the drum frame, the drum frame includes a base, a rotating shaft rotatably connected to the base, and a drum sleeved on the outside of the rotating shaft, the drum and the rotating shaft are connected by a plurality of connecting rods, the flexible tube is wound on the outside of the drum, a rotating handle is arranged on the outside of one end of the rotating shaft, the rotating handle is rotated to realize the rotation of the rotating shaft, and then the drum is driven to rotate, so as to realize the retraction and extension of the flexible tube on the drum; the structure of the flexible tube drum 21 is a conventional engineering structure, and any equipment that can realize the retraction and extension function of the flexible tube can be applied to the present application;

[0029] The upper end of the holder 22 introduces the flexible tube from the flexible tube drum 21 through the No. I guide 24, and the lower end of the holder 22 is connected to the tool string 23 through the No. II guide 25; the tool string 23 is injected into the riser 4 from the inlet end of the riser 4;

[0030] The clamp 22 is a conventional commercially available device, and any device that can achieve the clamping function can be applied to the present invention, such as the HR-5100 model product of the foreign NOV Hydra Rig company and the ZRT540 model developed by the domestic Hongyuan Petroleum Equipment Company. Both devices can meet the requirements of the present invention;

[0031] The tool string 23 is a rotating structure, which sprays out the mixture of light particles and water from the sand mixing unit 1 at high pressure to clean the inner surface of the pipeline, and can achieve fixed-point cleaning. At the same time, it carries a video system to achieve automatic monitoring during the work process; the structure and use method of the tool string 23 have been patented, and the patent name is "A tool string and construction process method for repairing the inner surface of a submarine mixed pipeline", and the patent number is 202410191639.6;

[0032] The guide No. Ⅰ 24 and the guide No. Ⅱ 25 have the same structure, both are bent into a semicircular shape, and the end surface forms a groove, which plays a supporting role for the tube, and the guide realizes the conversion from horizontal to vertical direction; the guide No. Ⅰ 24 is fixed to the top of the clamp 22 to realize the stable introduction of the flexible tube;

[0033] The flowback unit 3 includes a sand settling tank 31 and a centrifugal pump 32 which are interconnected through a pipeline;

[0034] The inlet of the grit tank 31 is connected to the outlet of the riser 4, and the outlet is connected to the inlet of the centrifugal pump 32. The liquid outlet of the centrifugal pump 32 is connected to the inlet of the liquid distribution tank 11, so that the separated water can be reused.

[0035] In the description of the present utility model, it should be understood that the terms "center", "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present utility model and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present utility model. In addition, the terms "first", "second", etc. are only used for descriptive purposes, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Therefore, features defined as "first", "second", etc. may explicitly or implicitly include one or more of the features. In the description of the present utility model, unless otherwise specified, "multiple" means two or more.

[0036] In the description of the present invention, it should be noted that, unless otherwise clearly specified and limited, the terms "installation", "connection" and "connection" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be an indirect connection through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood by specific circumstances.

[0037] The applicant declares that the above is only a specific implementation method of the present utility model, but the protection scope of the present utility model is not limited thereto. The technicians in the relevant technical field should understand that any changes or substitutions that can be easily thought of by the technicians in the relevant technical field within the technical scope disclosed in the present utility model fall within the protection scope and disclosure scope of the present utility model.

Claims

1. A system for cleaning the inner surface of a subsea pipeline riser and an expansion bend, characterized in that: It comprises a sand mixing unit (1), an injection unit (2) and a flowback unit (3); The sand mixing unit (1) comprises a liquid distribution tank (11), a functional component and a high-pressure manifold (15) which are sequentially connected through pipelines; the functional component comprises a plunger pump (12) and a sand mixing pump (14) which are connected in parallel, and a sand feeder (13) is provided at an upper inlet of the sand mixing pump (14); The injection unit (2) comprises a flexible tube drum (21), a clamp (22) and a tool string (23); the inlet end of the flexible tube of the flexible tube drum (21) is connected to the outlet of the high-pressure manifold (15); the upper end of the clamp (22) introduces the flexible tube from the flexible tube drum (21), and the lower end of the clamp (22) is connected to the tool string (23); the tool string (23) is injected into the riser (4) from the inlet end of the riser (4); The flowback unit (3) comprises a sand settling tank (31) and a centrifugal pump (32) which are interconnected via a pipeline; the inlet of the sand settling tank (31) is connected to the outlet of the riser (4).

2. The system for cleaning the inner surface of a subsea pipeline riser and an expansion bend according to claim 1, characterized in that: The flexible tube roller (21) connects the water source and the power source to the flexible tube via a slip ring and a rotary joint; the flexible tube is a multi-layer composite structure, in which a communication line and a power circuit are built-in.

3. The system for cleaning the inner surface of a subsea pipeline riser and an expansion bend according to claim 1, characterized in that: The clamp (22) is a crawler structure driven by a hydraulic system to inject the flexible tube into the pipeline, and the injection depth is calculated by a counter.

4. The system for cleaning the inner surface of a subsea pipeline riser and an expansion bend according to claim 1, characterized in that: The tool string (23) is a rotating structure.

5. The system for cleaning the inner surface of a subsea pipeline riser and an expansion bend according to claim 1, characterized in that: The liquid outlet of the centrifugal pump (32) is connected to the inlet of the liquid distribution tank (11).

6. The system for cleaning the inner surface of a subsea pipeline riser and an expansion bend according to claim 1, characterized in that: The upper end of the clamp (22) introduces the flexible tube from the flexible tube drum (21) through the invertor (24), and the lower end of the clamp (22) is connected to the tool string (23) through the guide (25).

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