CN108007792A - In-service deep seafloor buried pipeline earthquake-high pressure load combination loading test method - Google Patents

Abstract

The invention relates to a seismic-high pressure combined loading test method for deep seabed buried pipelines in service. The device used includes a cabin body, and the cabin body includes a cabin body body (4) and a hatch cover (3); a test pipe fitting (30) Located inside the main body of the cabin, the front end is connected with a high-temperature oil input hard pipe (24), which respectively penetrates the front flange (23) of the pipe fitting, passes through the front flange rubber interlayer (22), the front connecting flange (21) and the cabin After the flange (20) at the front end of the body, it is connected with the high-temperature oil input hole (17) on the hatch cover; a pipe-soil actuator (26) is fixed outside the test pipe fitting (30), and a data line is provided on it to pass through. hole (29). Test method: close the drainage hole, use the water inlet hole to inject water into the cabin, wait for a certain period of time after the water injection is completed, and wait until the soil inside the pipe-soil actuator is saturated with water, use the external high-temperature oil equipment to pass through the high-temperature oil The input hole injects high-temperature oil into the interior of the test pipe fitting, and outputs it to the high-temperature oil equipment through the high-temperature oil output hole.

Description

Combined seismic-high pressure load test method for in-service deep-sea submarine buried pipelines

technical field

The invention provides an earthquake-high pressure joint loading test device for buried pipelines in service in the deep sea. By using the device, the buried pipelines can be subjected to the joint action of high pressure and seismic loads at the same time, and it can approximate the earthquake that the buried pipelines are subjected to during service. and the role of submarine geological hazards to realize the safety assessment of in-service submarine buried pipelines.

technical background

Energy security and the core competitiveness of the world economy are more and more dependent on the utilization and development of marine resources. my country's South China Sea has huge oil and gas reserves, and a large amount of them are clean energy sources, with huge mining value. In recent years, my country has made great progress in the field of oil and gas development in the deep sea, and has accumulated a lot of experience in the shallow sea. However, in the deep sea field, especially in the South my country Sea, due to the complex and changeable environment and the many geological disasters on the seabed, the difficulty of oil and gas exploitation has suddenly increased, and the key core technologies involved need to be solved urgently.

Deep-sea oil pipelines account for a huge proportion of investment in deep-sea oil and gas development projects, and their design, construction and related technologies are the key to the development of deep-sea oil and gas resources. As the lifeline of offshore oil and gas resources, the safe operation of oil pipelines is an important guarantee for the effective utilization of deep sea oil and gas resources. In order to ensure the in-situ stability of oil and gas transmission pipelines, most of the oil and gas transmission pipelines are buried in actual engineering, which will be affected by high pressure, high temperature inflow and seismic loads during operation. However, due to its special geographical location and Geological conditions make seismic load the main control load of buried pipelines. All deep-sea oil and gas pipelines must undergo dynamic load calculation and test verification. Load, while taking into account the coupling effect of pipe and soil, has always been a difficult problem in the academic circle.

A large number of research results at home and abroad have shown that the scale test results can be used as a reference standard for actual design through related principles such as proportional approximation. The deficiencies in the combined loading test methods of deep-sea oil and gas pipelines at home and abroad mainly include:

1. In terms of ultimate load research, most of the tests at home and abroad are carried out by building special pressure equipment. The external load that can be simulated is single, mainly due to the influence of axial force or bending moment under the action of water pressure on the mechanical properties of submarine pipelines. Realize the local stability test under the combined action of multiple loads, and the coupling interaction between pipe and soil cannot be considered during the test process;

2. If the buried pipeline considers the pipe-soil coupling effect and applies seismic loads, the relevant equipment at home and abroad can only carry out similar tests under normal pressure or in shallow water environments, and cannot simulate the high-pressure loads on deep-sea pipelines;

3. Relevant devices at home and abroad cannot realize the dynamic test of deep-sea oil and gas pipelines under high pressure under the action of high water pressure and dynamic load at the same time.

Contents of the invention

The purpose of the present invention is to overcome the deficiencies of the prior art and provide a test method capable of simulating the seismic-high pressure combined loading of deep-sea buried pipelines in service. The invention introduces pipe-soil coupling effect, high temperature internal flow effect, external high water pressure and seismic load, and can realize combined loading of high temperature internal flow, external high water pressure and seismic load. Technical scheme of the present invention is as follows:

A combined seismic-high pressure loading test method for in-service deep seabed buried pipelines, the device used includes a cabin, and the cabin includes a cabin body (4) and a hatch cover (3);

The cabin is provided with a number of openings, including data acquisition holes (6), pressurization holes (7), vertical shock application holes (8), lateral shock application holes (11), bottom openings (10), lateral Opening hole (13), water inlet hole (14), drain hole (15), high temperature oil input hole (17) and high temperature oil output hole (16); vertical shock application hole (8) and lateral shock application hole A shock device is installed at (11), which is used to apply vibration loads to the pipe fittings in the radial direction;

The test pipe fitting (30) is located inside the main body of the cabin, and the front end is connected with a high-temperature oil input hard pipe (24), which respectively penetrates the front end flange (23) of the pipe fitting, passes through the front flange rubber interlayer (22), and the front end connecting flange (21) is connected with the high-temperature oil input hole (17) on the hatch cover behind the front flange (20) of the cabin body; the rear end is also connected with a high-temperature oil output hard pipe (39), which penetrates the tail end flange of the pipe fitting (38), after passing through the tail end flange rubber interlayer (37), the tail end connecting flange (36) and the cabin body tail end flange (35), it is connected to the high temperature oil output hole (16) at the cabin body rear end;

A pipe-soil actuator (26) is fixed on the outside of the test pipe fitting (30), and a data line piercing hole (29) is provided on it to ensure that the data measurement line passes through while also ensuring the smooth passage of high-pressure water; High-elastic rubber (25) is provided at both ends of the soil actuator (26), the cross section of which is a ring, the outer wall is in contact with the inner wall of the pipe soil actuator (26), and the inner wall is in contact with the outer wall of the test pipe fitting (30). To ensure that the soil does not scatter during the experiment;

The test steps include: after the test pipe fittings and the pipe-soil actuator are installed in place, use the side opening and the bottom opening to connect the vertical vibration actuator rod and the lateral vibration actuator rod with the vertical vibration device and the lateral vibration device respectively. Connected, then close the side opening and the bottom opening respectively, close the drainage hole, use the water inlet hole to inject water into the cabin, wait for the water injection to be completed, let it stand for a certain period of time, and wait for the soil inside the pipe soil actuator to be in a state of saturated water Finally, use the external high-temperature oil equipment to inject high-temperature oil into the test pipe fitting through the high-temperature oil input hole, and output it to the high-temperature oil equipment through the high-temperature oil output hole.

The invention considers the high pressure-seismic load joint loading under the pipe-soil coupling effect, and can realize the simultaneous application of high-temperature internal flow-earthquake-high pressure joint load under the pipe-soil coupling condition of the in-service deep-water buried pipeline in scale, simulating the deep seabed buried Pipeline extreme operating environment. Compared with the existing technology at home and abroad, the present invention has the following advantages: it can realize high-pressure-vibration load joint loading, use the pipe-soil actuator to realize the pipe-soil coupling interaction, and can apply two-way vibration load and high-temperature oil pressure load at the same time, as much as possible Possibility to make load cases realistic.

Description of drawings

Figure 1 Front view of hyperbaric chamber

Explanation of symbols in the figure: 1--hatch cover locking device support; 2--hatch cover locking device; 3--hatch cover; 4--cabin main body; 5--cabin body support; 6--data collection hole ;7--pressure hole; 8--vertical shock application hole; 9--vertical shock device; 10--bottom opening; 14--water injection hole; 15--drainage hole; 16--high temperature oil output Hole; 17--high temperature oil input hole; 18--tail stud; 19--tail stud fixing nut.

Figure 2 Top view of hyperbaric cabin

Explanation of symbols in the figure: 2—hatch cover locking device; 3—hatch cover; 4—cabin main body; 6—data collection hole; 7—pressurization hole; 8—vertical shock device; 11—lateral shock application Hole; 12—lateral shock device; 13—lateral opening; 14—water injection hole; 16—high temperature oil output hole; 17—high temperature oil input hole.

Figure 3 Schematic diagram of pipe-soil actuator

Explanation of the symbols in the figure: 20—front flange of cabin; 21—front connecting flange; 22—rubber interlayer of front flange; 23—front flange of pipe fittings; 24—hard pipe for high temperature oil input; 25— -high elastic rubber; 26--pipe soil actuator; 27--high temperature oil delivery inside the pipe fitting; 28--soil body; 29--data line piercing hole; 30--test pipe fitting; 31--vertical shock Actuating rod; 32--vertical shock actuating rod; 33--spherical connection groove; 34--shock loading ring; 35--cabin tail flange; 36--tail connecting flange; 37-- End flange rubber interlayer; 38--Flange at the end of pipe fittings; 39--High temperature oil output hard pipe; 40--Lateral shock actuator rod; 41--Lateral shock actuator rod; 42--Spherical connection slot.

Figure 4A-A cross-sectional schematic diagram

Explanation of symbols in the figure: 26--Pipe-soil actuator; 27--High temperature oil delivery inside the pipe fitting; 28--Soil body; 29--Data line piercing hole; 30--Test pipe fitting; 31--Vertical shock Actuating rod; 32—vertical shock actuating rod; 33—spherical connection groove; 34—shock loading ring; 40—lateral shock actuating rod; 41—lateral shock actuating rod; 42— Ball joint groove.

Detailed ways:

Below in conjunction with accompanying drawing, the specific embodiment of the present invention is described further:

As shown in Figures 1 and 2, a closed high-pressure environment is formed by using deep-water hyperbaric cabin equipment, which is mainly composed of a cabin body 4, a hatch cover 3 and a locking device 2 thereof. The whole cabin is fixed on the ground by being supported by the saddle 5, and the end cover 3 and its locking device 2 are supported and fixed on the ground by the support 1 of the hatch locking device. There are several openings on the main body of the cylinder, including data collection hole 6, pressurization hole 7, vertical shock application hole 8, bottom opening 10, lateral shock application hole 11, lateral opening 13, water inlet hole 14 , drain hole 15, high temperature oil output hole 16, high temperature oil input hole 17. Both ends of the test pipe fitting 30 are sealed, and the front end of the pipe fitting is connected with a high-temperature oil input hard pipe 24, which penetrates the front flange 23 of the pipe fitting, passes through the front flange rubber interlayer 22, the front connecting flange 21, the cabin front flange 20 and The hatch cover 3 is connected to the high-temperature oil input hole 17 on the cabin body, and the rear end is also connected to a high-temperature and high-pressure oil output hard pipe 39, which penetrates the tail end flange 38 of the pipe fitting, and is connected to the tail end via the end flange rubber barrier 37. After the flange 36, the cabin body tail end flange 35 and the tail stud 18, link to each other with the high-temperature oil output hole 16 on the cabin body. In this way, it is ensured that there is high-temperature oil inside the test pipe fitting 30 to simulate its actual operating state.

As shown in Figure 3 and Figure 4, the schematic diagram of the position pipe soil actuator device. The soil body 28 of different materials can be arranged inside the pipe-soil actuator cylinder 26, and its top is provided with a data line piercing hole 29 in order to ensure that the data measurement line passes through while also ensuring that the high-pressure water passes through smoothly. High-elastic rubber 25 is provided at both ends of the pipe-soil actuator cylinder 26, and its cross-section is a ring. Scattering does not occur. The shock heads 9 and 12 use servo hydraulic cylinders to apply different types of seismic loads. They pass through the front actuating rods 31 and 40 respectively, and are connected to the actuating rods 32 and 41 through universal balls. The other ends of the actuating rods 32 and 41 are respectively The universal ball is connected with the spherical connection grooves 33 and 42 on the shock loading ring 34, so as to ensure simultaneous loading of two-way shock without interference.

During the test, after the test pipe fitting 30 and the pipe-soil actuator cylinder 29 are installed in place, use the side opening 13 and the bottom opening 10 to connect the vertical vibration actuator rod 31 and the lateral vibration actuator rod 40 with the vertical vibration actuator respectively. The device 9 is connected to the lateral shock device 12 . Close side opening 13 and bottom opening 10 respectively afterwards, close drain hole 15, utilize water inlet 14 to cabin body interior water injection, treat that water injection completes, leave standstill for a certain hour, treat that pipe soil acts on moving cylinder 29 inner soil bodies as After being saturated with water, use external high-temperature oil equipment to inject high-temperature oil into the test pipe fitting 30 through the high-temperature oil input hole 17, and output it to the high-temperature oil equipment through the high-temperature oil output hole 16.

Claims (1)

1. a kind of in-service deep seafloor buried pipeline earthquake-high pressure load combination loading test method, used device include Nacelle, nacelle include nacelle main body (4) and hatchcover (3)；

Nacelle is provided with some perforates, including data acquisition hole (6), pressurizes hole (7), the vertical application well that impulses (8), laterally impulses Application well (11), bottom opening (10), lateral perforate (13), inlet opening (14), osculum (15), high temperature oil input hole (17) and High temperature oil delivery outlet (16)；Shock excitation device is installed in the vertical application well that impulses (8) and lateral application well (11) place that impulses, is used for Oscillating load is radially applied to pipe fitting；

Experiment pipe fitting (30) is located at nacelle body interior, and front end is connected with high temperature oil input hard tube (24), it penetrates pipe fitting respectively Front end flange (23), after front end flange rubber interlayer (22), front end connecting flange (21) and nacelle front end flange (20), with High temperature oil input hole (17) on hatchcover is connected；Rear end is equally connected with high temperature oil output hard tube (39), it penetrates pipe fitting tail end Flange (38), after flange at tail end rubber interlayer (37), tail end connecting flange (36) and nacelle flange at tail end (35), with nacelle The high temperature oil delivery outlet (16) of rear end is connected；

There is pipeclay pressurized strut (26) in the external stability of experiment pipe fitting (30), which is provided with data cable punched out (29) to ensure DATA REASONING line by while, can also ensure that high pressure water passes through；The internal both ends of pipeclay pressurized strut (26) are equipped with high-elastic rubber Glue (25), its cross section are annulus, and outer wall is contacted with pipeclay pressurized strut (26) inner wall, and inner wall connects with experiment pipe fitting (30) outer wall Touch, to ensure that the soil body is not scattered in experimentation；

Test procedure includes：After experiment pipe fitting and pipeclay pressurized strut are installed in place, respectively will using lateral perforate and bottom opening It is vertical to impulse operating bar and the lateral operating bar that impulses is connected with vertical shock excitation device and lateral shock excitation device, side is closed off afterwards To perforate and bottom opening, osculum is closed, using inlet opening to nacelle internal water flooding, treats that water filling finishes, stands certain time, After the soil body is saturated-water phase inside the pipeclay pressurized strut, using external high temperature oil equipment, via high temperature oil input hole to experiment Inside pipe fitting injects high temperature oil, and is exported by high temperature oil delivery outlet to high temperature oil equipment.