CN101187211B - A subsea excavator with dual functions - Google Patents

Abstract

The invention relates to a double-function subsea excavator, which is characterized in that it includes: a main frame and skid bodies arranged on the lower parts of both sides of the main frame, and the frame in the middle of the main frame is composed of hollow pipes In the middle part of the main frame, a buoyancy and instrument cylinder is provided, and the attitude comprehensive equipment including conventional monitoring device, control circuit and sonar receiving device connected to the water surface control room is arranged in the buoyancy and instrument cylinder. Monitoring system; the front and rear of the main frame are respectively provided with a sonar, and the two sides of the buoyancy and instrument cylinder are respectively provided with an axial flow pump driven by a motor, and the main frame below the water delivery pipe passes through the water delivery branch pipe Two rows of nozzles are connected, and the motor and sonar of the axial flow pump are respectively connected to the control circuit through transmission cables. The invention can be widely used in the maintenance process of subsea excavation, trenching and laying of subsea pipelines and pipelines.

Description

A subsea excavator with dual functions

technical field

The invention relates to a seabed excavator, in particular to a seabed excavator with dual functions, which can not only carry out foundation excavation for maintenance of seabed pipelines, but also carry out ditching and embedding of seabed pipelines.

Background technique

In offshore oil and natural gas development projects, in order to transport oil and gas to land or oil storage systems, a large number of submarine pipelines need to be dug and laid on the seabed, and these pipelines will gradually appear damage phenomena such as deformation, fracture and leakage during use, so timely , Effectively repairing damaged pipelines and laying new pipelines are important supporting projects in offshore oil and gas development projects. Before the maintenance of underwater pipelines, it is necessary to carry out basic excavation on the seabed to expose the pipelines and form a certain range of working surfaces around the maintenance points. Therefore, it is necessary to use special equipment for basic excavation of underwater pipeline maintenance - subsea excavators.

In the process of laying new pipelines, it is also necessary to excavate and trench the seabed first, and then to bury the pipeline. For seabed excavation or ditching operations, what the prior art generally adopts is that a water pump is connected with a nozzle, and the seabed is sprayed with a single pressure water column. This device is too crude, its working efficiency is low, its underwater positioning control performance is extremely weak, its operation control performance is also relatively poor, and its comprehensive efficacy and performance cannot meet the needs of current production.

Contents of the invention

In view of the above problems, the object of the present invention is to provide a double-function subsea excavator that can not only carry out foundation excavation for subsea pipeline maintenance, but also perform trenching and embedding of subsea pipelines.

In order to achieve the above object, the present invention adopts the following technical solutions: a double-function subsea excavator, characterized in that it includes: a main frame and skid bodies arranged at the lower parts of both sides of the main frame, the main frame The frame in the middle is a water main pipe composed of hollow pipes. A buoyancy and instrument cylinder is arranged in the middle of the main frame. The buoyancy and instrument cylinder is provided with a conventional monitoring device, a control circuit, A posture comprehensive monitoring system including a sonar receiving device; the main frame is provided with a sonar at the front and rear respectively, and the two sides of the buoyancy and instrument cylinder are respectively provided with an axial flow pump driven by a motor, and the water main pipe The lower main frame is connected to two rows of nozzles through water delivery branch pipes, and the motor and sonar of the axial flow pump are respectively connected to the control circuit through transmission cables.

A skid extension body is respectively installed at both ends of the skid body, and a bow guide roller assembly and a stern guide roller assembly are respectively arranged on both sides of the front end and the rear end of the main frame.

A limit sensor and a preload spring assembly are respectively arranged at the bottom of the bow and stern guide roller assemblies.

The two rows of nozzles are group-distributed nozzles connected to the branch water pipe and located at the same level.

Each of the two rows of nozzles has eight nozzles.

The two rows of nozzles are connected to the water branch pipe at intervals, and the height of the nozzles at the rear is gradually increasing relative to the height of the nozzles at the front, and protrudes downward.

The number of nozzles of the stepped nozzle assembly is three.

Each pair of nozzles of the stepped nozzle assembly is provided with a relatively inward bevel.

Due to the adoption of the above technical scheme, the present invention has the following substantive features and obvious advantages: 1. The present invention provides two working conditions, and only needs to change the nozzle, assemble and disassemble the bow and stern extension skid and the guide pulley block when changing the working condition Only the hardware is sufficient, and other major equipment does not need to be modified in any way. 2. When the present invention is used as a foundation excavation, because of the group of nozzles, the excavation area formed at one time is large, the spraying effect is smooth, the spraying range is not limited, and the spraying depth can be adjusted according to needs. 3. When the present invention is used as trenching and buried pipe, the stepped nozzle is used to ensure the depth of the trench, and the nozzle has an inward bevel, and the jets on both sides converge at the bottom of the trench, and there is no convex circle in the middle of the trench, so that The groove shape is more perfect. The invention can be widely used in the maintenance process of subsea excavation, trenching and laying of subsea pipelines and pipelines.

Description of drawings

Fig. 1 is the schematic diagram of front view of foundation excavation state structure of the present invention

Figure 2 is a schematic top view of Figure 1

Figure 3 is a schematic side view of Figure 1

Fig. 4 is a schematic diagram of the front view of the state structure of the trenched and buried pipe of the present invention

Figure 5 is a schematic top view of Figure 4

Figure 6 is a schematic side view of Figure 4

Detailed ways

The present invention will be described in detail below in conjunction with the accompanying drawings and embodiments.

As shown in Figures 1 to 3, this embodiment includes a main frame 1 and skid bodies 2 arranged on the lower parts of both sides of the main frame 1, and the frame in the middle of the main frame 1 is a water main pipe 3 composed of hollow pipes. (as the frame part of mesh font among the figure 2), a buoyancy cylinder and instrument cylinder 4 are arranged above the water main pipe 3, and the buoyancy cylinder and instrument cylinder 4 are provided with conventional monitoring devices, control circuits, Attitude integrated monitoring system including sonar receiving device, etc. A sonar frame 5 is respectively arranged at the front and rear ends of the main frame 1, and a sonar 6 is respectively arranged on each sonar frame 5, and the sonar 6 is used for positioning the submarine pipeline. On both sides of the buoyancy cylinder and the instrument cylinder 4, an axial flow pump 7 driven by a motor is respectively arranged, and a plurality of group distribution nozzles 9 located on the same horizontal plane are arranged under the water delivery main pipe 3 through a plurality of water delivery branch pipes 8, and the group distribution nozzles Each water inlet of 9 is connected to the water outlet of axial flow pump 7 through water delivery branch pipe 8, water delivery main pipe 3, and each water delivery branch pipe close to group distribution nozzle 9 is connected into one body through longitudinal pipe section and connected with skid body 2 Diagonal struts 10 for enhancing stability are arranged between them.

In the above-mentioned embodiment, the axial flow pump 7 is two high-power axial flow water pumps, which can provide the group distribution nozzles 9 with a flow rate of 7200 cubic meters per hour and a pressure of 0.8Kg for spraying water, and carry out the operation of excavating the seabed through the spraying water column , group distribution nozzle 9 has two groups of 16 in the present embodiment (only this is example, but not limited to this), is divided into two rows and arranged in the scope of long 6 meters, wide 1.5 meters, and its jet flushing water column excavates the seabed It can form an excavation surface of 3m x 6m on the seabed foundation, the effect of spraying is smooth, the scope of spraying is not limited, and the depth of spraying can be adjusted according to needs.

When the present invention repairs the submarine pipeline, it is necessary to dig out the buried layer above the damaged pipeline to expose the pipeline. The basic operation process is as follows:

1. Hang the excavator above the pipeline to be repaired on the seabed, and the excavator is close to the seabed;

2. The operator adjusts the attitude and position of the excavator at the bottom of the water through the attitude comprehensive monitoring system in the water surface control room according to the data collected by the two sonars 6, so that the two rows of group nozzles 9 are located at the position to be excavated above;

3. Start the motor to drive the axial flow pump 7 to run. At this time, seawater enters through the inlet of the axial flow pump 7, enters the group distribution nozzles 9 through the water delivery main pipe 3, and the outflowing water column sprays to the seabed to carry out the operation of excavating the seabed foundation.

According to the actual needs of maintenance, the surface mother ship tows the excavator to move horizontally, and the excavator can excavate the excavation surface required for the maintenance of the pipeline along the pipeline. If the excavation depth does not meet the requirements, you can adjust the depth of the excavator on the basis of the excavation surface for the first spraying, and then spray down and back again until the required depth is reached.

As shown in Fig. 4, Fig. 5, and Fig. 6, the difference between this embodiment and the above-mentioned embodiment is that a skid extension body 11 is respectively installed at both ends of the main frame 1 skid body 2, and left, Right two bow guide roller assemblies 12, left and right two stern guide roller assemblies 13 are arranged at the main frame 1 rear end, and the guide pulley assembly can do slight swing around the fixing bolts on the upper end of the installation base. A limit sensor 14 and a preload spring assembly 15 are arranged at the bottom of the guide roller assemblies 12, 13. The function of the limit sensor 14 is to detect the swing of the guide roller assemblies 12, 13, thereby indicating that the pipeline is attached to the side of the excavator. The pressure spring assembly 15 is to give a prestress to the guide roller assemblies 12, 13. When the force of the pipe attached to the roller assemblies is greater than the prestress, the guide roller assemblies 12, 13 will swing to the outside, and the limit sensor 14 will generate a signal to allow the operation staff know. A stepped nozzle assembly 16 that replaces the group nozzles 9 is provided at the lower part of the water delivery branch pipe 8 , and the water inlet end of the stepped nozzle assembly 16 is connected to the water outlet of the axial flow pump 7 through the water delivery branch pipe 8 and the water delivery main pipe 3 .

In the above-mentioned embodiment, as shown in FIG. 4 , the stepped nozzle assembly 16 has six nozzles (only as an example, but not limited thereto), which are divided into two rows on the left and right, and are divided into three pairs according to the order of the front and back, in a stepped shape. Each row of nozzles is connected and fixed to the water delivery branch pipe 8 through seven flanges, of which the three flanges leading to the nozzles can pass through water, and the remaining four flanges are blind flanges that do not pass through water and only serve as a support. A pair of branch pipes at the forefront of the water branch pipe 8 are also blocked with blind flanges. The first pair of nozzles of the stepped nozzle assembly 16 is close to the base surface of the excavator, the second pair of nozzles is 0.5 meters lower than the first pair of nozzles, and the third pair of nozzles is 0.5 meters lower than the second pair of nozzles. During operation, the six nozzles of the stepped nozzle assembly 16 have an effective range of 0.5 meters to 0.7 meters to the seabed, so a buried pipe trench with a depth of 1.5 meters to 2 meters can be excavated at one time on the seabed.

In the present invention, each pair of nozzles of the stepped nozzle assembly 16 is provided with a relatively inward bevel, so that the jets on both sides converge at the bottom of the groove, so that there is no convex circle in the middle of the groove, so that the shape of the groove is more perfect. Simultaneously the present invention stretches the state when the 3rd pair of nozzles of stepped nozzle assembly 16 below the seabed, is set as the landing state of skid body 2 (promptly contacting the seabed state), keeps steady state when moving along pipeline to guarantee excavator .

The ditching operation process when the present invention is used for pipeline embedding is as follows:

1. Lift the excavator above the seabed where the pipeline is buried;

2. The operator controls the posture and position of the excavator at the bottom of the water through the posture comprehensive monitoring system in the water surface control room according to the display conditions of the two sonars 6, so that the stepped nozzle assemblies 16 arranged in two rows on the left and right straddle the On both sides of the pipeline, at the same time, two left and right bow and stern guide roller assemblies 12 and 13 are respectively straddled on both sides of the submarine pipeline;

3. Control the starting motor to drive the axial flow water pump 6 to run. The seawater is sucked by the inlet of the axial flow water pump 7, and enters the nozzles of each stepped nozzle assembly 16 through the water delivery main pipe 3 and the water delivery branch pipe 8, and sprays to the bottom of the sea. The nozzle has a deep spraying effect. With the deepening of the trenching operation, the third pair of nozzle openings of the stepped nozzle assembly 16 will gradually extend below the seabed, gradually making the skid body 2 of the excavator land on the ground (i.e. contact with the seabed state).

4. While the stepped nozzle assembly 16 is continuously spraying and digging the trench to the seabed, slowly move the working mother ship on the water surface, drag the excavator to move along the position of the pipeline trench, and keep the skid body 2 on the ground at the same time, the trenching depth is It can be guaranteed, and the walking direction of the excavator can be adjusted according to the indication of the limit sensor 14 at any time.

5. The pipeline that needs to be buried will gradually sink to the bottom of the ditch by its own weight, and then the pipeline will be buried by the silting of the seabed.

The present invention has group distribution nozzles 9 and stepped nozzle assemblies 16 at the same time, and can carry out two operations of subsea foundation excavation and trenching respectively. When changing operating conditions, only the group distribution nozzles 9 and the stepped nozzle assemblies 16 need to be exchanged, and Assembly and disassembly of skid extension body 9 and guide pulley assemblies 12, 13 etc. get final product, and other main parts need not make any changes.

Claims (9)

1. seabed excavator with dual-use function, it is characterized in that: it comprises: main frame and the skid body that is arranged on described main frame two side lower parts, the water delivery house steward that the framework at described main frame middle part is made up of hollow tube, the one buoyancy instrument tube of holding concurrently is set at described main frame middle part, and described buoyancy is held concurrently and is provided with the attitude comprehensive monitor system that comprises conventional monitoring arrangement, control circuit, sonar receiving system that is connected with water surface control room in the instrument tube; The forward and backward sonar that is respectively arranged with of described main frame, the hold concurrently both sides of instrument tube of described buoyancy, be respectively arranged with the axial-flow pump of a driven by motor, connect two row's nozzles by delivery pipe branch on the main frame below the described water delivery house steward, the motor of described axial-flow pump is connected described control circuit by transmission yarn respectively with sonar.

2. a kind of seabed excavator as claimed in claim 1 with dual-use function, it is characterized in that: install a skid ennation respectively additional at the two ends of described skid body, bow guide roller assembly and stern guide roller assembly are set respectively in the both sides, front-end and back-end of described main frame.

3. a kind of seabed excavator with dual-use function as claimed in claim 2 is characterized in that: in the bottom of described bow, stern guide roller assembly one limit sensors and a pre-compressed spring assembly are set respectively.

4. a kind of seabed excavator with dual-use function as claimed in claim 1 is characterized in that: described two row's nozzles are the group's cloth nozzle that is positioned at same level height that is connected on the described delivery pipe branch.

5. a kind of seabed excavator with dual-use function as claimed in claim 4 is characterized in that: the every row of described two row's nozzles is eight.

6. a kind of seabed excavator with dual-use function as claimed in claim 1 or 2 is characterized in that: described two row's nozzles increase progressively the staged nozzle assembly that protrudes out downwards for the nozzle height that is connected the relative front of nozzle height on the described delivery pipe branch, the back at interval is.

7. a kind of seabed excavator with dual-use function as claimed in claim 6, it is characterized in that: the nozzle quantity of described staged nozzle assembly is three.

8. a kind of seabed excavator with dual-use function as claimed in claim 6, it is characterized in that: every pair of nozzle of described staged nozzle assembly is provided with inside relatively oblique angle.

9. a kind of seabed excavator with dual-use function as claimed in claim 7, it is characterized in that: every pair of nozzle of described staged nozzle assembly is provided with inside relatively oblique angle.

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