RU2324100C2 - Method of underwater pipe laying, realization system and complexes of joining pipes used - Google Patents

Abstract

FIELD: construction of pipeline transport.

SUBSTANCE: floating system of pipelining can rise above waves and has polynia of corresponding sizes. The assembling complex for joining pipes underwater, which is done within the pipe, is taken down with the pipes to the bottom and the pipe is joined to the previous one with subsequent extraction and placement on the floating system for further work.

EFFECT: expansion of arsenal hardware.

3 cl; 8 dwg

Description

The present invention relates to the construction of pipeline transport and is used when laying underwater pipelines of large diameter.

There are various ways of laying a pipeline under water, as well as systems that implement them, and installation complexes for connecting pipes used in them (see City engineering networks and collectors. Leningrad, Stroyizdat, Leningrad branch, 1990, p.206-216; p. 249-266; p. 310-332). They can be divided into four groups:

1) pulling the pipeline along the bottom;

2) laying by immersion of the pipeline from the surface of the reservoir by pouring water into the pipeline (pontoons), by pulling off the pontoons or by loading by various methods;

3) the descent of the pipeline from supports equipped with lifting devices mounted on ice, or using floating cranes;

4) laying of the pipeline from pipe-laying barges, vessels of various types.

The essence of the first group of methods is to drag the pipeline along the bottom of the underwater trench. At the same time, the pipeline is welded on the shore into a string, pressed, insulated, lined, and, if necessary, ballasted and equipped with pontoons. At the same time, a trigger track is arranged, on which the pipeline prepared for installation is then placed, and dragged by a cable through a water barrier using a tugboat, tractors, winches, etc.

As systems that implement the first group of known methods, systems are used that include ships, pontoons, tractors, as well as winches and other technical means and an assembly complex for connecting pipes into a string, using a welding unit installed on the shore.

These methods are effective in the manufacture of an underwater pipeline from pipes of small diameter having a large specific gravity. Typically, these pipes have a diameter of up to 1.5-2 meters.

However, as practice shows, pulling long lashes from such pipes along the bottom of the water area is a complex process and its success largely depends on weather conditions both on the surface of the water area and in its depths.

The essence of the second and third groups of known methods of laying a pipeline under water is that the pipeline is welded from separate pipes on the shore and then, using the appropriate system, the pipeline is installed in the cross section and immersed at the bottom of the underwater trench by moving an additional distributed load (water gulf, etc. )

To implement these two groups of known methods, systems are used that include a dam or overpass, as well as ships, pontoons, tractors, winches and other technical means, including an assembly complex, which is used as a welding unit for welding pipes into a string.

These well-known methods, as well as their implementation systems and pipe connection mounting systems used in them, are more often used when crossing non-navigable water barriers or when it is possible to stop shipping in the cross section for the period of laying the pipeline by loosening special devices that hold the pipeline on the surface of the water, or moving floating supports.

As an assembly complex for connecting a pipeline of pipes, welding units are used that are located on the shore.

However, these known methods of laying submarine pipelines, systems that implement them, and installation complexes for connecting pipes into the pipeline have a significant drawback. They are not suitable for laying a pipeline along the bottom of the water area if the pipeline is assembled from pipes of especially large diameter, for example more than 1.5 meters, made of lightweight materials, such as fiberglass reinforced plastic, and / or having protruding structures, or made of materials that "work poorly" "bending (concrete, cast iron).

This is due to the fact that pipes of light materials, especially if pipes of large diameter, are evenly coated with concrete, which, when laying the pipeline to the bottom by known methods, can break, peel off. The same will happen when using pipes made of materials that "work poorly in bending." If you use the methods of the second and third groups for a pipeline with a large diameter, then you will need to use temporary dams or overpasses, which is economically inexpedient and will cause disruption of the ecosystem in the construction area. In addition, there will be problems in securing the pipeline at the bottom if the pipeline is made of light materials and has a large diameter, since it will be necessary to use local ballasting in the form of local weights, which greatly complicates the implementation of pipe-deepening work, as local ballasts favor the dimensions of the pipeline. If you use anchors, you will need the work of a diver, which is dangerous for his life because of the need to perform a large amount of work on their installation and fixing at the bottom.

A common drawback of these well-known submarine pipeline laying systems and assembly systems for connecting pipes into threads is that they are used ashore for the continuous formation of pipeline threads. This limits their ability to create pipelines from light materials (fiberglass reinforced), as well as from a material that "works poorly" in bending (concrete, cast iron).

The essence of the last known group of methods for laying a pipeline under water is the use of a floating system, on which the pipeline is expanded by sequential supply of pipes and their connection using an assembly complex, which uses a welding unit installed with the possibility of continuous interaction with pipes on an inclined section of the deck ( ramp), equipped with roller bearings, at the same time being a launching device, and the descent itself is carried out with or without stinger - in the case of shallow depths.

For example, inventions are known under the name “Ship pipe layer (options) and the method of laying pipelines (options)” (see Patent of the Russian Federation No. 2230967, MKI F16L 1/19, publ. 2004.06.20). The essence of the method known from this invention for laying a pipeline from a vessel, which performs the function of a submarine pipeline laying system, consists in connecting the parts of the pipeline into a string, with their subsequent laying on the bottom of the water area. In such a system, a pipe assembly is used to connect the pipes to the pipeline, which is mounted on the vessel with the possibility of interacting with a tower pre-positioned on the bow and pivotally mounted there with the possibility of tilting forward with the top forward in the assumed direction of movement of the pipeline gasket and the bottom of the tower in the opposite direction. In this case, periodically raise a segment of the pipeline in line with the tower, join the segment of the pipeline to the laid pipeline and lower the pipeline into the water, directing the pipeline at the moment of its exit from the vessel by means of a roller trigger ramp. It should be noted that the tower is installed next to the bow of the vessel in the expected direction of movement of the pipeline and before raising the length of the pipeline in line with the tower, the specified length of the pipeline is collected on the vessel in a mainly horizontal position from the pipe sections. The lowering of the pipeline is carried out while maintaining the specified tension in the pipeline, and at the time of interruption of the laying process, the pipeline is gripped by at least one clamp below the tensioning devices, and it is captured by tensioning devices before lowering the pipeline. As an assembly complex, a welding unit is used.

As a system that implements this known method of laying a pipeline, a floating system is used - a pipe-laying vessel, which contains a tower mounted on the bow and pivotally mounted on it with the possibility of tilting forward with the top forward in the assumed direction of movement of the pipeline laying and the bottom of the tower in the opposite direction . On the pipe-laying vessel there are also means for lifting a section of the pipeline from the deck into a common line with the tower, means for connecting the specified section of the pipeline to the laid pipeline and a lower trigger ramp, which is equipped with rollers and installed with the possibility of guiding the pipeline when it is launched from the vessel. The vessel is also equipped with a system for assembling pipe sections into a longer section of the pipeline, tensioning devices installed with the ability to capture the stacked pipeline and lowering it into water while maintaining the required tension in the pipeline, and at least one clamp installed with the ability to capture the pipeline below the tension devices. The vessel also has an assembly complex for connecting pipes into a thread, which is a welding unit with two grippers, covering part of the pipeline, in particular pipes, from the external surface and providing welding of four pipe sections. Moreover, the welding unit is installed with the possibility of interaction with the tower and with tensioning devices, exciting and stretching the pipeline.

Known installation complex connecting pipes into the pipeline used in the previously mentioned system for laying an underwater pipeline. This well-known assembly complex is a welding unit, in which there are two grips of parts of the pipeline, as well as welding heads made with the possibility of welding the ends of the joined pipes, and the grips are made with the possibility of external coverage of the ends of the pipes.

These well-known technical solutions are selected as prototypes, since they are closest in their technical essence to the claimed inventions and represent the latest developments that have found application in the practice of laying underwater pipelines. In addition, they have the largest number of essential features that match the essential features of the claimed inventions.

The technical solutions selected as prototypes are united by a single inventive concept, since all of them both individually and together solve problems that solve the claimed inventions.

These well-known technical solutions allow, in comparison with analogues, faster and more cost-effective to carry out the laying of the pipeline under water along the bottom of the water area and at great depths.

However, the prototypes are not applicable when laying underwater pipelines made of lightweight materials, for example reinforced fiberglass, especially large diameters, for example more than 1.5 meters, or from materials that "work poorly" in bending (concrete, cast iron), and / or with protruding structures, for example, water intakes. These well-known inventions are also unacceptable for laying tunnels for various purposes under water.

For example, pipelines with a diameter of 3000 mm are made of light alloys. To give them the necessary negative buoyancy, a layer of concrete is applied on the outside. If you use a prototype for laying a pipeline of such pipes under water, this will lead to the destruction of the pipeline. In addition, prototypes are not acceptable for laying underwater tunnels for various purposes, assembled from separate parts of complex shape, for a similar reason.

The first objective of the present inventions is to create a new method for laying a large diameter underwater pipeline made of lightweight materials (fiberglass reinforced plastic), as well as a material that "works poorly" in bending (concrete, cast iron). Moreover, the task is to create a method that would allow to achieve technical results inherent in the method of laying large diameter pipelines on land, when the connection of the pipeline parts into a string occurs continuously, and inherent in the continuous laying of a small diameter pipeline to the bottom of the water area from a floating system.

The second task is to create a system that would allow to implement the created new method for laying underwater pipelines and achieve a technical result, namely, simplified the design and ensured high reliability of the connection of the pipeline parts at the bottom.

The third task is the creation of a new installation complex for connecting parts of the pipeline under water, which ensures the implementation of both the created method and the system that implements it, ensuring the achievement of a technical result, such as: automation of the process of laying parts of a large diameter pipeline into a pipeline thread along the bottom of the water area while reducing participation of divers in connecting parts of the pipeline under water and reducing the risk to their life.

The first problem is solved as follows. In the known method of laying an underwater pipeline, which consists in assembling the pipeline parts on a floating system, connecting the pipeline parts using an assembly complex to the pipeline laid at the bottom of the water area, according to the present invention, the pipeline is laid in a previously formed trench, the pipeline parts are alternately lowered to the bottom of the trench and connected to pipeline using an installation complex containing a catcher with an outer cross-sectional dimension smaller than the inner cross-sectional dimension of the joint parts of the pipeline, and two movable in the longitudinal direction of the gripper, made with alternately or simultaneously changing their external dimensions of the cross section from a smaller internal size of the cross section of the connected parts of the pipeline to at least the outer size of their cross section and vice versa, while the catcher is installed at one end of the assembly complex, one capture is connected to the stern of the catcher, and the second capture is located in the middle of the assembly complex, and floating the system is made in the form of a barge with the possibility of controlled self-raising and lowering over a section of the bottom of the water area and with a lane larger than the dimensions of the connected parts of the pipeline, and with the possibility of moving the floating system to the section of the water area above the pipeline, and on the floating system, before lowering each part to the bottom of the trench the pipeline into the cavity of the section of the pipeline intended for the next lowering from the one end of the pipeline, the installation complex is introduced until the part of the pipeline of the trap closest to the opposite end to it the gripper and the working distance between the grippers, fix the installation complex in the pipeline part by increasing the outer dimension of the cross section of the last gripper of the installation complex, and connect the part of the pipeline with the previous one by introducing from the free end into the previous part of the pipeline protruding from the end of the attached part of the catcher pipeline and the capture closest to the catcher with their subsequent fixation by increasing the outer cross-sectional dimension of the capture closest to the catcher that, they draw the lowered part of the pipeline to the previous one before joining their ends by converging in the longitudinal direction of the grippers of the installation complex, and after joining the ends, they are rigidly connected to each other, for example, by means of bolted joints made on their outer walls, the fixing of the installation complex is removed and through the free end of the last connected part of the pipeline, they are removed, delivered to a floating system, which is moved to the next section of the underwater pipeline.

This new technical solution allows you to quickly, and in some cases cost-effective, lay a particularly large diameter pipeline along the bottom of open and closed water areas, made of lightweight materials, such as reinforced fiberglass, or materials that "work poorly" in bending (concrete, cast iron ), i.e. a technical result is achieved, which was impossible to provide by known methods. In addition, the proposed solution can be used for the construction of underwater tunnels from individual sections, which is also not possible to achieve using known methods.

Compared with the prototype of the inventive method of laying an underwater pipeline has significant differences, which are that:

- the procedure for laying a pipeline under water was changed, in particular, it was proposed to lower a part of the pipeline, for example, a separate pipe or section, to the bottom from the floating system, to dock it with the previously laid part of the pipeline while laying it on the bottom. In essence, the achievement of the technical result inherent in laying large-sized pipelines on land is ensured. But under water this technical result is achieved by the present invention, since they use a special floating system, for example, in the form of a barge having a lane larger than the dimensions of the omitted sections of the pipeline, as well as the corresponding assembly complex for connecting these parts into a string;

are offered:

- an appropriate connection system in the form of an installation complex having an extended shape and different from the known installation systems for connecting pipes into a pipeline;

- an assembly complex that not only works underwater, but also contributes to the smooth lowering of part of the pipeline from the floating system to the bottom, and is capable of accurately bringing one part down to the other part of the pipeline under water and then ensuring their connection;

- a floating system, for example, in the form of a barge with the ability to controlled self-raising and lowering over a fixed section of the bottom of the water area, which ensures a stable position of the floating system above the laying section of the underwater pipeline and with the possibility of controlled change of its vertical position above it and with a lane having dimensions larger sizes of the connected parts of the pipeline.

A patent information search carried out by the applicant showed that the claimed combination of essential distinguishing features was not found.

The proposed method for laying an underwater pipeline for a specialist of average skill does not logically follow from the prior art and therefore is unexpected, because contrary to the prevailing trend in the development of technology for laying a pipeline under water at the bottom of the water area.

Thus, the analysis of known methods of laying a pipeline along the bottom of the water area (see analogues and prototype) shows that whips or a string of the pipeline or extended parts of the pipeline are formed on the surface, then the entire pipeline or its string is laid at the bottom of the trench or lowered continuously with the simultaneous formation of the string the pipeline.

On the other hand, there is a known method of laying a tunnel along the bottom of the water area (see Patent of the Russian Federation 2252300, MKI E02D 2/063; EV 02/17, publ. 05.20.2005). According to this known method of laying a tunnel along the bottom of the water area over a section of the water area, a temporary fence is created from a floating dock made without a bottom, water is pumped out of the enclosed enclosed space, and then the bottom is opened in a dry way and sections of the tunnel are laid on it. Moreover, their laying is carried out in the same way as on land, as they are combined. Similarly, in the place of the tunnel, it is possible to lay a pipeline for which the claimed invention is proposed.

In the claimed method, the process is different. First, lower a separate part of the pipeline (a pair of already connected pipes or a separate pipe) and lay it on the bottom. Then the next separate part of the pipeline is lowered and connected to the previous pipe in a thread under water with their simultaneous laying on the bottom, and then the next pipe is laid and the cycle is repeated until the pipeline is completely formed under water. Moreover, in some cases, for example, depending on the topography of the bottom, the connection of the subsequent pipe with the previous one is carried out simultaneously with the laying of the connected pipe in the alignment of the previous one. This technical result is not achievable by known methods of laying underwater pipelines.

The second problem is solved as follows. In the known system for laying an underwater pipeline, comprising a floating system for lowering parts of the pipeline to the bottom and an assembly complex for connecting them into a string, having two grips of the ends of the pipes to be connected, according to the present invention, the floating system is made in the form of a self-propelled vessel or a barge with a lane in a hull larger than sizes of the connected parts of the pipeline, and with vertical support columns extendable under the barge and installed on the bottom of the water area, which are located on the stern and bow or along the sides of the bar they are connected to its hull with the possibility of vertical movement of the barge along them after they are installed at the bottom of the water area, and the assembly complex for connecting the pipeline parts has an extended shape and a catcher with an external cross-sectional dimension smaller than the internal cross-sectional dimension of the connected pipeline parts is installed at one end thereof and on the other - two grips of the parts of the pipeline, made movable in its longitudinal direction and with alternating or simultaneous change in their external dimensions of the transverse sections from the smaller internal cross-sectional dimension of the pipe parts to be connected to at least the outer cross-sectional dimension and vice versa, with one grip connected to the stern of the trap and covers a telescopic tube concentrically removed from the stern of the trap, and the second grip is concentric on the opposite end of the tube and connected to it, while in the longitudinal direction, the grippers are still interconnected using the rods of hydraulic cylinders located in the housing of the second gripper, on the outer surface of the gripper bodies there are elements, for example, in the form of air bags, changes in the transverse dimensions of the grippers, and through the internal cavity of the telescopic tube, power hoses for hydraulic cylinders and elements for changing the transverse dimensions of the grippers are connected, which are connected to the corresponding units located on the floating system.

Such a new technical solution allows to implement the above method of laying an underwater pipeline, in which it is possible to lower it under water alternately and there to connect parts of the pipeline, for example, the previously mentioned pipes, to each other. Moreover, the implementation of the proposed method is provided in almost automatic mode and underwater, which reduces the physical load on the divers or even eliminates their participation. At the same time, simple operations can be used to lay the pipeline under water, which are easy to control and perform using simple devices, for example, standard cranes located on its body, which allow loading of pipes and lowering parts of the pipeline to the bottom of the water area.

In addition, we note that in this system it becomes possible to monitor and control the process of laying the pipeline to the bottom by installing acoustic sensors in the lower part of the barge supports, and to receive data from them in one of the working rooms of the floating system. In addition, to remove soil that has fallen into a previously laid pipeline, the nose of the installation complex can be equipped with hydraulic monitors, which can also be installed on lowered pipes to remove soil from a previously formed trench by erosion of this soil. Moreover, the catcher of the assembly complex may have water intake openings so that water located in the lowered pipe earlier does not create a lot of pressure on the assembly complex when it is introduced into it. Such an expansion of functionality cannot be achieved in the known submarine pipeline systems.

Compared with the prototype of the inventive system for laying an underwater pipeline has significant differences, such as:

- the floating system is made in the form of a vessel or a barge with a lane having dimensions larger than the overall dimensions;

- on the floating system, retractable support columns are installed, allowing the vessel or barge to take a rigid position over the bottom of the water area, along which the vessel or barge can rise or fall, which reduces the effect of waves on the process of lowering parts of the pipeline to the bottom and on their connection under water;

- the assembly complex for connecting the parts of the pipeline into a thread is made with a catcher at one end and with two grippers on the other, capable of changing their cross-sectional dimensions and which, on the one hand, can capture parts of the pipeline from their ends at the inside, and on the other - connect them to each other under water, and after connection to be removed to work with the following parts of the pipeline;

- the system for ensuring the functioning of the installation complex is located on a floating system, which allows you to remotely and quickly manage the installation complex when it is used under water.

The proposed system for laying an underwater pipeline and its technical solution do not logically follow from the prior art, but rather contradict the prevailing tendency in the development of this purpose of the systems.

So, it was previously noted that the analysis of the known systems for laying the pipeline along the bottom of the water area shows the presence of many different systems in them, some of which are located on land, and others - in the water area. In particular, the assembly complex for connecting pipes to each other is located either on land (see analogues) or on a ship (see prototype). Another system continuously lays the thread on the bottom as it forms on the previous system. Moreover, these known systems operate in a mode consistent with each other, which is difficult to ensure, since they not only have different functions, but often they are located at great distances from each other, in particular pallets that provide loading of parts of the pipeline that are lowered into the water . In the proposed application, systems are created that are simple in design, control, and the functions they perform, and they are all compactly located on one floating system.

In addition, the presence in the installation system of the connection of the pipe parts to each other, allowing inside to capture the connected parts of the pipeline, since it has, for example, air cushions, improves control of the process of lowering the connected parts of the pipeline to the bottom and performing their connection under water. Moreover, there is always the opportunity to stop the process of laying the pipeline under water and resume it again from the place of termination. It is difficult to accomplish this using known systems.

The third problem is solved as follows. In a known installation complex for connecting parts of a pipeline containing two grippers of the ends of the pipes to be joined, according to the present invention, the grippers of the parts of the pipeline have an extended shape, are movable in its longitudinal direction and alternately or simultaneously changing their outer cross-sectional dimensions from a smaller inner cross-sectional dimension of the connected parts of the pipeline to at least the outer size of their cross-section, while a catcher is installed at one end of the complex l with an external cross-sectional dimension smaller than the internal cross-sectional dimension of the connected parts of the pipeline, moreover, one gripper is connected to the stern of the trap and covers a telescopic tube concentrically withdrawn from the stern of the trap, and the second grab is concentric on the opposite end of the tube and connected to it, moreover, in the longitudinal direction, the grippers are interconnected by the rods of hydraulic cylinders located in the housing of the second gripper, and on the outer surface of the gripper housings dynamic elements, for example, in the form of air bags, changes in the transverse dimensions of the grippers having a feed channel passing through the inner cavity of the tube to the end surface of the second gripper body, nozzles for supplying water from the hydraulic motor and ventilation holes, which are connected to the corresponding hoses, are made on the outer surface of the trap passing through the internal cavity, connected with the end surface of the housing of the second capture.

Compared with the prototype, the proposed technical solution has significant differences, which are not only in its execution, i.e. in design, but also in principle. As noted earlier, the claimed working body of the installation complex of the connection of the parts of the pipeline can function under water and hold the connected parts of the pipeline from the inside. This is not possible in known systems for connecting parts of a pipeline, since they are built on a different approach to capturing the connected parts of a pipeline. In addition, the proposed installation complex has an additional function, for example, the ability to pass oncoming water through itself, and in essence work as the suction head of the corresponding pump.

The inventive installation complex for connecting pipe parts for a specialist does not logically follow from the prior art, but rather contradicts the current tendency to create a similar purpose of working bodies for mounting complexes for connecting pipe parts. So, in known systems for connecting parts of a pipeline, parts of connected pipes are seized from the outside. Then they are pulled together to fit snugly at the end edges with the help of other systems and perform their rigid connection in the same way as claimed. After that, the grips release the connected part of the pipeline for further work with it using other working bodies of the mentioned system. In the claimed case, the grips work inside the connected parts of the pipeline and under water with simultaneous laying of the formed part of the thread on the bottom of the trench, which cannot be done with the help of known mounting systems for connecting parts of the underwater pipeline. This is due to the fact that the inventive installation complex has a catcher, made in the form, in particular, of a cone. It allows you to orient the joined part of the pipeline in relation to the joined. For clamping their ends to each other, the installation complex has grips located coaxially with the catcher from the side of its aft and installed with the ability to converge with each other in the longitudinal direction and diverge from each other at a certain distance in the same direction. The grips can change their outer cross-sectional size.

All the stated technical solutions are united by a single inventive concept. So, the first method cannot be implemented without the claimed system, and without the declared installation complex, there is not only a cost-effective implementation of the method for laying an underwater pipeline from individual pipes or from sections of the pipeline, but the claimed system for laying an underwater pipeline cannot be implemented. At the same time, the claimed working body of the assembly complex for connecting parts of the pipeline can be used in other systems when it is necessary to connect parts of the pipeline that do not allow capture by the outer surface. However, this option is not considered in this application and requires additional study.

Thus, the claimed group of inventions eliminates the need for laying pipelines from separate pipes (sections) with preliminary filling and subsequent dismantling (washing out) of the dam or mounting and dismounting a flyover to ensure the operation of cranes. In addition, it virtually eliminates the use of crane vessels in rough seas, which ensures safety both for the work of divers and for the integrity of the stacked pipe (section). Moreover, this group of inventions allows to automate as much as possible the process of laying a pipeline from individual pipes, including pipes with structures protruding from the outside.

The practical applicability of the claimed technical solutions is illustrated by drawings, where:

Figure 1 - diagram of a system for laying an underwater pipeline and its implementation of the claimed method;

Figure 2 - General view of the installation complex (MK) connecting parts of the pipeline used in the said system;

Figure 3 - diagram of the introduction of MK into the cavity of a previously laid pipeline;

Figure 4 - scheme of the extension and fixation of MK with pneumatic pillows in the cavity of a previously laid pipeline;

Figure 5, 6 is a diagram of the convergence of the ends of the stacked pipe and the previously laid pipeline;

7 is a diagram of the main communications of the installation complex of the connection of the pipeline parts;

Fig. 8 is a view of a pipe section with hydraulic monitors and mounts.

The practical applicability of the proposed method is as follows.

First, establish a route for laying an underwater pipeline in the water area. Select the parameters of the pipeline 1, such as: the diameter and configuration of pipes or parts of the pipeline (not shown). In particular, for our case, the length of the underwater pipeline was chosen - 16 km. The laying depth is 16 m. In this case, the pipes 2 were selected with a diameter of 2.2 meters and made of fiberglass reinforced (Figure 1). Then, under these parameters, at the bottom 4, a corresponding trench was made.

So, the proposed method consists in assembling parts of pipeline 2 on a floating system 3, connecting parts of pipeline 2 using an assembly complex 5 to pipeline 1 laid on the bottom 4 of the water area. In this case, the pipeline is laid, as noted above, on the bottom 4 of the previously formed trench . Parts of the pipeline 2 from the floating system 3 are alternately lowered to the bottom 4 of the trench and connected to the pipeline 1 using an assembly complex 5, in which there is a catcher 6 with an external cross-sectional dimension smaller than the internal cross-sectional dimension of the connected parts of the pipeline 2, and two movable in the longitudinal the direction of capture 7, 8, made with alternate or simultaneous change in their external dimensions of the cross section from a smaller internal size of the cross section of the connected parts of the pipeline 2 to, as mum, the outer size of their cross section and vice versa. In this case, the catch 6 is installed at one end of the mounting complex 5, one grip 8 is connected to the aft of the catch 6, and the second catch 7 is located in the middle of the mounting complex 5. The floating system 3 is made in the form of a barge with the possibility of controlled self-raising and lowering over the bottom water area and with lane 9, having dimensions larger than the dimensions of the connected parts of pipeline 2, and with the possibility of moving the floating system 3 to a section of the water area above pipeline 1. Moreover, on a floating system 3, before lowering to the bottom 4 of each part of the pipeline of the water supply pipe 2, the assembly complex 5 is introduced into the cavity of the pipeline part 2 scheduled for the next lowering from one end of the pipe until the catcher 6 of the pipeline 2 exits from the opposite end, the capture 7 closest to it and the working distance between the grippers 7 and 8, the mounting complex 5 is fixed in part pipeline 2 by increasing the outer cross-sectional dimension of the last gripper 8 of the mounting complex 5. It should be noted that the connection of the part of the pipeline 2 with the previous one is carried out by introducing from the side of the free end of the main part of the pipeline protruding from the end of the attached part of the pipeline of the trap 6 and the capture 7 closest to the trap 6 with their subsequent fixation by increasing the outer cross-sectional dimension of the trap 7 closest to the trap 6. The lowered part of the pipeline 2 is pulled to the previous one until their ends are joined together in the longitudinal the direction of the grips of the mounting complex 5 (Fig.5, 6). After joining the ends, they are rigidly connected to each other, for example, by means of bolted joints made on their outer walls (not shown), the fixing of the mounting complex 5 is removed and through the free end of the last connected part of the pipeline 2 it is removed and delivered to the floating system 3 which is moved to the next section of the underwater pipeline 1.

To implement this method, as already noted, use the underwater pipeline system (Figure 1). It contains a floating system 3 of lowering the parts of the pipeline 2 to the bottom 4 of the trench and an assembly complex 5 of their connection in the thread, having two grips 7, 8 ends of the connected pipes. The floating system 3 is made in the form of a self-propelled vessel or a barge with a lane 9 in a hull that is larger than the dimensions of the connected parts of the pipeline 2, and with vertical support columns extending under the barge and installed on the bottom of the water area 10. They are placed on the stern and fore or on the sides of the barge and connected to its hull with the possibility of vertical movement of the barge over them after they are installed on the bottom of the water area. The installation complex 5 of the connection of the parts of the pipeline 2 has an extended shape (Fig.2, 3, 4, 5, 6, 7). A trap 6 is installed at one end thereof with an outer cross-sectional dimension smaller than the inner cross-sectional dimension of the connected parts of the pipeline, and at the other, two grippers 7, 8 of the pipeline 2, made movable in its longitudinal direction and alternately or simultaneously changing its outer dimensions cross section from a smaller internal cross-sectional dimension of the connected parts of the pipeline to at least the outer dimension of their cross-section and vice versa. In this case, one gripper 8 is connected to the stern of the trap 6 and covers a telescopic tube 20 concentrically removed from the stern of the trap 6, and the second grab 7 is concentrically located on the opposite end of the tube 20 and connected to it. In the longitudinal direction, the grippers 7, 8 are interconnected using the rods of hydraulic cylinders located in the housing of the second gripper 7, and on the outer surface of the housing of the grippers 7, 8 there are elements, for example, in the form of air cushions, changing the transverse dimensions of the grippers. Through the internal cavity of the telescopic tube 20, hoses 15 for supplying the hydraulic cylinders 16, elements for changing the transverse dimensions of the grippers, which are connected to the corresponding units located on the floating system 3. are passed. More specifically, the proposed underwater pipeline installation system is as follows. As a floating system 3, a self-elevating drilling rig with a removed drilling complex can be used, having a lane 9 of appropriate sizes, in this case 14-30 m, and equipped with the equipment necessary for the performance of work, such as:

2 cranes 11 designed for:

- loading another batch of pipes 2 from a pipe barge (not shown) moored to a self-propelled barge 3,

- lowering the pipes 2, equipped, if required, with weights 12 (Fig. 7), to lane 9;

one assembly complex (MK) 5, which includes:

- mounting catcher - cone 6 for connecting pipes 1, 2,

- hydraulic monitors 13 (Fig.7) to adjust the profile

trenches 4, if necessary (Figure 1);

one sonar complex 14 (Fig.7), intended for:

- positioning the barge 3 above the end of the laid pipe 2 before lifting the barge to the required height for installation work,

- visualization of the operation of combining the ends of the stacked and previously laid pipes 1.

To reduce the volume of underwater work and, taking into account the possible length of the mounted pipes, equal to 10-14 m, it is advisable to assemble 2-pipe sections on the barge deck.

Pipes to ensure the necessary stability on the ground during the construction process when exposed to currents and sea waves should have weights 12, providing them with the required bulk density regulated by regulatory documents and taking into account the parameters of sea currents and sea waves in the pipeline construction area.

As already noted, on the floating system 3, i.e. On the barge, there is a mounting complex 5 (MK) for connecting parts of pipeline 2. This MK contains two grips 7, 8 extended by the shape of the ends of the connected pipes. Captures 7, 8 of the pipe 2 are movable in its longitudinal direction and with alternate or simultaneous change in their external cross-sectional dimensions from a smaller internal cross-sectional dimension of the connected pipe parts 2 to at least the outer size of their cross-section. At one end of the installation complex 5, a catcher 6 is installed with an outer cross-sectional dimension smaller than the inner cross-sectional dimension of the connected parts of the pipeline. Moreover, one grip 8 is connected to the stern of the trap 6 and covers a telescopic tube 20 concentrically withdrawn from the stern of the trap 6. The second grip 7 in MK is concentrically located on the opposite end of the tube 20 and connected to it. In the longitudinal direction, the grippers 7 and 8 are interconnected by rods of hydraulic cylinders located in the housing of the second gripper 7. On the outer surface of the housing of the grippers 7 and 8 there are dynamic elements for changing the transverse dimensions of the grippers, for example, in the form of air cushions having a feed channel 15 passing through the inner the cavity of the tube 20 to the end surface of the housing of the second capture 7. On the outer surface of the trap 6 are made nozzles 19 for supplying water from the hydraulic monitors 17 and ventilation holes 19, which through the corresponding s hoses extending through the inner cavity, associated with an end 21 of the second gripping surface 8 of the housing.

So, in a pre-made trench at the bottom of the water area from the floating system 3, parts of the pipeline (pipes) 2 are alternately lowered and connected into it with a thread using an assembly complex (MK) 5 (Figs. 2, 3, 4, 5, 6, 7 ) Moreover, on the floating system 3, before lowering to the bottom 4 of each part of the pipeline 2, an assembly complex 5 is introduced into the cavity of the pipeline part scheduled for the next lowering from one end thereof until the part of the pipeline of the catcher 6 closest to it 7 and the working distance between the grips exit the opposite end 7 and 8 (Figs. 1, 3). Then fix the mounting complex 5 in it by increasing the outer dimension of the cross section of the last capture of the mounting complex. The connection of the next part of the pipeline 2 with the previous one is carried out by introducing from the free end into the previous part of the pipeline a catcher 6 protruding from the end of the connected part of the pipeline and the capture 7 closest to the catcher and then fixing them therein by increasing the already outer dimension of the cross section closest to the catcher. Then they draw the lowered part of the pipeline 2 to the previous one before joining their ends by converging in the longitudinal direction of the grippers 7 and 8 of the mounting complex 5 and, after joining the ends, they are rigidly connected to each other, for example, using bolted joints made on their outer walls. Upon completion of this connection in the connected parts of the pipeline, the fixation of the mounting complex 5 is removed and through the free end of the last connected part of the pipeline 2 it is removed and delivered to the floating system 3. After that, the floating system 3 is moved to the next section of the underwater pipeline 1 and the underwater pipeline laying cycle with floating system 3 repeat.

To reduce the volume of underwater work and, taking into account the possible length of the mounted pipes, equal to 10-14 m, it is advisable to assemble 2-pipe sections on the barge deck.

Pipes to ensure the necessary stability on the ground during the construction process when exposed to currents and sea waves should have weights 12, providing them with the required bulk density, regulated by regulatory documents and taking into account the parameters of sea currents and waves in the area of pipeline construction 1.

Pipe laying technology includes the following steps:

1) barge 3 by means of a positioning system (anchor or dynamic with thrusters) is installed above the docking point of the stacked pipe 2 with previously laid 1 (Figure 1);

2) the supporting columns 10 are lowered to the ground and the barge 3 is raised on them, taking into account the clearance required for the sea waves under the given conditions;

3) the lowering pipe 2 is equipped with MK 5 elements:

- from the side of the abutting end - by the mounting cone 6. Hoses 15 for supplying working media with parameters necessary for performing the corresponding operations are passed from the other end of the pipe (Fig. 7);

- on the sides of the pipe 2 at the lower generatrix of the weights mounted pipe-hydraulic monitors 16, equipped with nozzles 17 (Fig), through which water is supplied under pressure to adjust the profile of the trench and, accordingly, the position of the pipe being laid;

4) the regulation of the position of the lowered pipe is carried out by cranes 11, and also due to the horizontal displacement of the lines in the area of lane 9 (Figure 1);

5) in the process of lowering the pipe for joining with the previously laid pipe, the control of its spatial position is carried out both by monitoring the position of the marked lines, and by means of hydroacoustic sensors 18 located in the lower part of the columns 10 (Figure 1);

6) after combining the position of the axes and end sections of the joined pipes, the catcher 6 with the bow of the base is moved to the previously laid pipe for final docking and fixed by distributing this base with compressed air;

7) a further rapprochement of the pipes 1, 2 is carried out by pulling together 2 grippers of the catcher 6 located in these pipes (Figs. 3, 4, 5, 6);

8) the final fixation of the position of pipes 1, 2 is done by divers using bolted joints located on both sides of the pipes (not shown). The combination of the holes for the bolts on the joined pipes 1, 2 is ensured by their corresponding orientation with respect to the eyelets on the weights of the laid pipe, for which the slings are fastened;

9) at the end of the pipe docking operation 1, 2, the assembly complex 5 together with the hoses 15 is removed from the pipe 2, rises to the deck of the barge 3 in the same way as the hydraulic monitors.

The main characteristics of a possible variant of barge 3 for laying pipes 1, 2 with a diameter of up to 2.2 m and a length of 14 m and the composition of the main equipment

Length - 55 m

Width - 20 m

Column height - 28 m

Working depth - from 3 to 16 m

Total displacement - 2200 t

Payload (pipes and weights) - 500 t

3 columns for lifting the barge and mechanisms for raising and lowering the columns

Power plant, including 2 600 kW diesel generators

Energy block systems:

hydraulic station

compressor station

2 cranes for loading and laying pipes with a lifting capacity of 7 tons with a reach of 17 m

Assembly complex for pipe joining

Hydroacoustic complex

Soil erosion control monitors

Tunnel type thrusters:

nasal

aft with reverse gear screw

Roll and trim system

Pump room

Pipe racks

Fire extinguishing system

Diving Station

Life support systems

Service premises:

control posts - 2

dining room

galley with provisions storeroom

skipper

supplies pantry

Living spaces:

single cabins - 3

2 berth cabins - 6

The crew - 15 people

including:

The installation of the installation complex (MK) 5 (Fig.2, 7)

In this case, the grips 7, 8 are connected by a telescopic tube 20.

The functioning process of MK 5 includes the following operations.

After docking the 2-pipe sections on the deck, the MK with the hoses rolls into them from the left end (Figure 1).

For rigid fixation of the trap 6 at the other end of the pipe, compressed air is supplied to the pneumatic pillows (PP) of the trap bases. In this case, the grips 7, 8 are in direct contact with each other.

When the trap 6 enters the cavity of the previously laid pipe 1 (after centering their axes) into the nozzles of the hydraulic monitors 13 located in the lower part of the catcher 6 (in the bow and middle parts), water is supplied under pressure to wash sand from the cavity of the previously laid pipe 1. After convergence of the ends of the pipes 1, 2, the pressure in the PP is relieved.

When applying pressure to the hydraulic cylinders 21, the trap 6 enters the cavity of the previously laid pipe and is rigidly fixed in it after supplying compressed air to the PP (Figs. 2, 3, 4, 5, 6). When applying pressure to the right side of the hydraulic cylinders 21, the pipes 2 are finally docked and sealed by, for example, rubber rings included in the docking unit (not shown).

To remove MK 5 from the cavity of the laid pipe 2, the pressure in the PP is relieved, the grippers 7 and 8 come together and after the pressure is relieved in the PP of the feed base of the MK along with the hoses, it is removed from the cavity.

The device of hydraulic monitors

Laying the pipeline in the prepared trench does not exclude the possibility that local sand deposits can occur in it.

Therefore, to ensure the required position of the pipe to be laid on the ground and to eliminate the need for divers to work with hydraulic monitors to wash the soil, the pipe on the sides is equipped with hydraulic monitors, which are pipes with nozzles into which water is supplied under pressure (Figure 2).

Hoses 15 to individual sections of the pipes of the hydraulic monitor are connected through the control unit to the pumps.

Hydromonitors 17 are attached to the stacked pipe on 2 half-clamps (Fig. 8).

The monitor mounts (half clamps) for stiffness are interconnected by ribs (not shown).

"Mounting" of the hydraulic monitors on the pipe is carried out after assembling the 2-pipe section on the barge deck (to simplify the manipulations when lifting the hydraulic monitors and storing them, they can be made of 2 sections).

The clamps are fixed with cotter pins, which, after laying the pipe for lifting the hydraulic monitors, are removed from the holes. Hydroacoustic complex 14 (Fig.7).

The emitters and receivers of acoustic signals are placed in pairs at the bottom of the aft columns 10 (Figure 1).

The results of sonar echolocation after appropriate conversion are served on the monitor screen (Fig.7).

Claims (3)

1. The method of laying an underwater pipeline, which consists in assembling the pipeline parts on a floating system, connecting the pipeline parts using the installation complex to the pipeline laid at the bottom of the water area, characterized in that the pipeline is laid in a previously formed trench, the pipeline parts are alternately lowered to the bottom of the trench and connected with a pipeline using an assembly complex containing a catcher with an external cross-sectional dimension smaller than the internal cross-sectional dimension of the connected parts th pipeline and two grippers moving in the longitudinal direction and with alternating or simultaneous changes in their external cross-sectional dimensions, from the smaller internal cross-sectional dimension of the connected pipeline parts to at least the outer cross-sectional dimension and vice versa, while the trap is mounted at one end assembly complex, one capture is connected to the stern of the catcher, and the second capture is located in the middle of the installation complex, and the floating system is made in the form of a barge with the possibility of controlled self-raising and lowering over the section of the bottom of the water area and with a lane that is larger than the dimensions of the connected parts of the pipeline and with the possibility of moving the floating system to the section of the water area above the pipeline, and on a floating system, before lowering to the bottom of the trench of each part of the pipeline into the cavity intended for the next lowering parts of the pipeline from one of its ends introduce the installation complex until the part of the pipeline of the catcher, the closest capture to it and the working distance, exit from the opposite end between the grips, the assembly complex is fixed in the pipeline part by increasing the external cross-sectional dimension of the last gripper of the installation complex, and the connection of the pipeline part with the previous one is carried out by introducing from the free end side the previous part of the pipeline protruding from the end of the joining part of the pipeline of the catcher and the closest to the catcher their subsequent fixation by increasing the outer dimension of the cross-section of the gripper closest to the catcher, attract the lowered part t water supply to the previous one prior to joining their ends by converging in the longitudinal direction of the grips of the installation complex, and after joining the ends, they are rigidly connected to each other, for example, using bolted joints made on their outer walls, the fixing of the installation complex is removed and through the free end of the last the attached part of the pipeline is removed, delivered to a floating system, which is moved to the next section of the underwater pipeline. 2. A system for laying an underwater pipeline, comprising a floating system for lowering parts of the pipeline to the bottom and an assembly complex for connecting them into a string, having two grips of the ends of the pipes to be connected, characterized in that the floating system is made in the form of a self-propelled vessel or a barge with a lane in a hull measuring larger sizes of the connected parts of the pipeline, and with vertical support columns extendable under the barge and installed on the bottom of the water area, which are located at the stern and bow, or along the sides of the barge and connected to its hull with the possibility of vertical movement of the barge over them after they are installed at the bottom of the water area, and the assembly complex for connecting the parts of the pipeline has an extended shape and a catcher is installed at one end with an external cross-sectional dimension smaller than the internal cross-sectional dimension of the connected parts of the pipeline, and two grips on the other parts of the pipeline, made movable in its longitudinal direction, and with alternating or simultaneous changes in their external dimensions of the cross section from smaller to the size of the cross-section of the connected parts of the pipeline to at least the outer size of their cross-section and vice versa, while one grip is connected to the stern of the trap and covers a telescopic tube concentrically removed from the stern of the trap, and the second grip is concentric at the opposite end of the tube and connected to it, in the longitudinal direction, the grippers are interconnected using the rods of hydraulic cylinders located in the housing of the second gripper, on the outer surface of the gripper housings ra put elements, such as bellows, transverse grippers changes size, and through the inner cavity of the telescopic tube carried supply hoses cylinders, grippers transverse elements changes the size, which are connected to the respective assemblies, arranged on a floating system. 3. An assembly complex for connecting parts of the pipeline, comprising two grips of the ends of the pipes to be joined, characterized in that the grips of the parts of the pipeline having an extended shape are made movable in its longitudinal direction and with alternate or simultaneous changes in their external cross-sectional dimensions from the smaller internal cross-sectional dimension of the connected parts of the pipeline to at least the outer dimension of their cross section, while at one end of the complex there is a trap with an outer dimension m cross-section smaller than the internal cross-sectional dimension of the connected parts of the pipeline, and one grip is connected to the stern of the trap and covers a telescopic tube concentrically removed from the stern of the trap, and the second grip is concentric on the opposite end of the tube and connected to it, and in the longitudinal in the direction of the grippers are interconnected by rods of hydraulic cylinders located in the housing of the second gripper, and on the outer surface of the gripper housings are dynamic changes in the transverse dimensions of the grippers, for example, in the form of pneumatic pillows having a power channel passing through the inner cavity of the tube to the end surface of the second gripper body, and nozzles for supplying water from the hydraulic monitors and ventilation holes, which through corresponding hoses passing through the inner one, are made on the outer surface of the trap cavity associated with the end surface of the housing of the second capture.

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