RU2392380C1 - Floating facility for drilling wells from support units - Google Patents

Abstract

FIELD: oil and gas production.

SUBSTANCE: floating facility for drilling wells from support units containing a "П"-shaped pontoon with a telescopic console platform whereon a derrick and equipment for well drilling are arranged, a power unit, a residential unit, load-lifting cranes, technological unit modules with warehousing premises for drilling, a helicopter landing platform and integrated columns for installation on sea bottom, lifting mechanisms providing for lifting the pontoon to the operating position above the sea level, equipped with means for mounting the pontoon onto the support unit arranged in a "П"-shaped aperture while the lifting mechanisms are designed in the shape of hydraulic cylinders serving for the pontoon relocation relative to the columns and along them so that to provide for their dismantling for the well drilling period. Additionally in the floating facility the pontoon is equipped with hydraulic lifters on frame posts intended for submerge of the support unit to the sea bottom. The technical solution enables improved efficiency of the facility operation due to provision for possibility of extending the facility operation period to be all years round in regions of minor depths, in Arctic regions and in regions where structures are subject to ice impact.

EFFECT: creation of a floating facility design ensuring its all year round operation round in regions of minor depths, in Arctic regions and in regions where structures are subject to ice impact as well as serving for drilling wells from support units and for the support units installation on the sea bottom which for the period of drilling wells at a sea oil and gas deposit is mounted onto a conductor unit or a support unit and is not subject to ice impact.

5 cl, 16 dwg

Description

The invention relates to offshore floating drilling rigs designed for drilling wells in offshore oil and gas fields.

Known self-propelled floating drilling rig, which is installed near the conductor block attached to the seabed, advances the cantilever platform with the drilling tower located on it and carries out drilling of wells through water separating columns inside the conductor block. Subsequently, after the completion of the drilling of the wells, the cantilever platform with the derrick is removed from the conductor block by sliding the cantilever platform onto the floating drilling rig, and the upper structure with processing equipment for receiving the production of the wells and its preparation for transportation through the pipeline to the tanker are installed on the conductor block ships or onshore points ["Innovative semi-submersible drilling platform for drilling using support vessels". Consortium "Uralmash-Industrial drilling rigs, 2008].

The disadvantage of such installations is that they cannot be used in areas with ice and ice cover, in the Arctic regions due to the lack of protection from ice impacts not only on the structure of the installation, but also the design of the installation itself is a concentrator of ice accumulations at the block conductor, leading to a significant increase in ice impact on the block conductor.

A known design of a floating installation with a U-shaped hull, with the help of which the support blocks of offshore stationary oil and gas production platforms are transported and installed on the seabed, but they are structurally and technologically not designed to install derricks on the support blocks and are not protected from ice [[Marine oil and gas fields "C.S. Huseynov, V.K.Ivanets, D.V.Ivanets. M .: Publishing House "Oil and Gas" Russian State University of Oil and Gas. N. M. Gubkina, 2003, p. 56, sheet 3, 4].

Also known is the installation of an offshore drilling platform, which consists in installing the carrier deck with the upper structure assembled on a support block fixed to the seabed. With this installation method, the support block in the upper part is made with an opening in which the transport barge is brought in and is installed in the position for lowering onto the support block of the carrier deck with the upper structure assembled. The descent is provided by reducing the draft of the transport barge due to its ballasting and the operation of hydraulic jacks installed between the bottom of the carrier deck and the deck of the transport barge. At the same time, the designs of the support tables of the support block for supporting the supporting deck on them are equipped with special damping devices for absorbing large dynamic loads from the rolling of the transport barge as a result of wave action. Such structural and technological features significantly complicate the construction of the structure and the construction equipment and increase the cost of construction [GB patent No. 2176827A of June 19, 1985 "Method for installing the superstructure of the offshore platform." United Kingdom].

The aim of the invention is the creation of the design of the floating installation, ensuring its year-round operation in places with shallow depths in the Arctic regions and in areas with the presence of ice impacts on the structures, as well as serving for drilling wells from support blocks and for installing support blocks on the seabed, a floating installation for the period of drilling wells in an offshore oil and gas field is installed on a block conductor or support side and is not exposed to ice impact, and design solutions and technologist I also provide marine construction decline in its construction costs and increase reliability and safety of construction and installation works in comparison with existing similar installations.

This goal is achieved in that a floating installation for drilling wells from support blocks, containing a U-shaped pontoon with a retractable cantilever platform and a drilling rig and equipment for drilling wells located on it, an energy block, a residential block, cranes, technological block modules with storage pads for drilling, a helipad and built-in columns for installation on the seabed, lifting mechanisms for lifting the pontoon to its working position above sea level, equipped with tools for installation the pontoons are mounted on the support block located in the U-shaped opening, and the lifting mechanisms are made in the form of hydraulic cylinders (lifting devices) serving to move the pontoon relative to and along the columns.

This goal is also achieved by the fact that the means for installing the pontoon on the support block is installed on the inner surface of the U-shaped opening.

This goal is achieved by the fact that the means for installing the pontoon on the support block is made in the form of rotary or extendable elements.

At the same time, lifting operations to install the support unit on the seabed, install the floating installation with the upper structure on the support unit are carried out with a floating installation that is not afloat and supported by support columns on the seabed, which significantly increases the threshold of permissible weather conditions for work in the sea conditions.

The proposed technical solution is illustrated by drawings, where:

figure 1 shows an example of a floating installation for drilling wells with support blocks;

figure 2 is the same, plan view;

figure 3 shows the bearing hinged rotary or sliding elements on the pontoon to support the support block;

figure 4 shows the location of the piles of the support block in plan;

figure 5 shows the steps of installing the pontoon on the support unit, the installation of a floating installation to the support unit;

figure 6 is the same, plan view;

in Fig.7 - the support of the floating installation on the seabed with column devices;

Fig.8 is the same plan view;

figure 9 - lifting the floating installation using columns and the exposure of the support elements for installation on the support block;

figure 10 is the same, plan view;

figure 11 - lowering the floating installation on the support block;

Fig.12 is the same plan view;

on Fig - extension of the drilling rig on the console in the working position on the support block;

Fig.14 is the same plan view;

on Fig - lifting the columns to the floating installation and positioning of the floating installation to perform well drilling from the support blocks;

in Fig.16 is the same plan view.

A floating installation for drilling wells from support blocks contains a pontoon 1 (Fig.1-2), which houses the column devices 2, 3, 4 and 5, a drilling complex 6, a power unit 7, a residential unit 8 with a helipad 9, hoisting cranes 10 11 and 12 and frame racks 13-16 with hydraulic lifting devices 17-20. The drilling complex 6 consists of a derrick 21, a sub-module 22 (sub-portal), module 23 and a cantilever part (portal) 24. In the U-shaped opening 25, wall 26 (Fig. 3) is equipped with load-bearing hinged rotary elements 27 or retractable elements 28 for installation on the support block 29. Column devices 2-5 contain glasses 30-33, which are bolted to the structure of the pontoon body 1. Actually columns 34-37 in the lower part are equipped with shoes 38-41 for abutment in the ground, and in the upper part they have 42-45 hydraulic lifting devices for hoisting dema-lowering columns 34-37 with respect to the pontoon 1.

The design of the support block 29, on which the floating installation for drilling wells is mounted, must have dimensions that allow it to pass into the opening 25 of the pontoon 1. A design variant of the support block 29 is shown in figure 1 and consists of a cylindrical part 46, the upper part of which has cantilevered protrusions 47, serving as a support for the supporting deck of the pontoon with pivoting pivot 27 or sliding elements 28. The middle part of the support block 29 has a cone ice protection device 48, and the lower part is equipped with a pile foundation 49 with skirt tracks 50 for piles 51 and with suction piles 52.

On the anchored on the seabed, the support block 29 is brought into the desired position with the U-shaped opening of the pontoon 1 and, using tugs, is lowered to the bottom of the column 34-37. The rise of the pontoon 1 along the columns 34-37 is produced using hydraulic lifting devices 42-45 to a height up to the design position of the installation of the pontoon 1 on the support block 29.

The hinged rotary elements 27 or the sliding elements 28 are brought into the design position, after which the pontoon 1 is lowered using hydraulic lifting devices 42-45 along the columns 34-37 until it stops in the upper part of the support block 29 structure. After the pontoon 1 is fixed on the support block 29 Disconnect from pontoon 1 and shoot columns 34-37.

For installation in the working position of the drilling complex 6, the extension of the cantilever part 24 to the position for drilling wells. The drilling rig is moved to the coordinate of the well grid by moving the sub-module 22 and the sub-portal module 23.

In the embodiment of setting the support block 29 to the seabed using a real floating installation, the descent to the seabed of the support block 29, wound up in a U-shaped opening 25 and sprinkled to the frame posts 13-16, is carried out using hydraulic lifting devices 17-20.

Implementation of the proposed technical solution will allow, in comparison with existing similar installations, to reduce the cost of construction of the installation, increase the reliability and safety of construction and installation works, increase the efficiency of use of the installation by providing the possibility of extending the installation period to year-round in areas with shallow depths, in the Arctic regions and areas with the presence of ice impacts on structures.

Claims (5)

1. A floating installation for drilling wells from support blocks, containing a U-shaped pontoon with a retractable cantilever platform and a drilling rig and equipment for drilling wells located on it, an energy block, a residential block, hoisting cranes, technological block modules with storage areas for drilling, helipad and built-in columns for installation on the seabed, lifting mechanisms for moving the pontoon to a working position above sea level, characterized in that it is for installing the pontoon on the support block nabzhena means, which are arranged in the U-shaped opening, and lifting devices are designed as hydraulic cylinders which serve to move relative to the pontoon and columns along them and arranged to dismantle them at during drilling. 2. The floating installation according to claim 1, characterized in that the means for installing the pontoon on the support block is located on the inner surface of the U-shaped opening. 3. The floating installation according to claim 1 or 2, characterized in that the means for installing the pontoon on the support block is made in the form of rotary elements. 4. The floating installation according to claim 1 or 2, characterized in that the means for installing the pontoon on the support block is made in the form of sliding elements. 5. The floating installation according to claim 1 or 2, characterized in that the pontoon is equipped with hydraulic elevators on the frame racks, which serve to lower the support block to the seabed.

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