SU70346A1 - Mobile base for marine drilling - Google Patents

Description

The invention relates to the construction of mobile bases for offshore rigs, in which a submerged barge is used as the bottom of the base.

A distinctive feature of the proposed movable base is that a pontoon is placed between the upper part of the base and the flooded barge, which is intended to support the upper part of the base when the barge is in a horizontal position.

FIG. 1 shows a general view of the proposed mobile base in a floating state; in fig. 2 - the same base after installation on the seabed; Fig. 3 is a vertical section of the fixing device of the base; in fig. 4 - ABCD section.

The proposed movable base consists of an upper part I, auxiliary pontoons 2 and a lower part 3 (barges) with supporting columns 4 for supporting the upper part of the base. The latter is a metal structure consisting of a series of sections connected to each other.

sections of pipes 5 of larger diameter, through which the columns 4 pass. The upper part of the base thus forms a platform designed to carry all drilling equipment and form platforms for pipelines and alumina platforms.

The bottom part 3 of the base is a reinforced concrete barge with supporting columns 4 embedded in it, which are arranged in several rows. Between the columns for stiffness provided farm.

The bottom part 3 of the base serves as a base plate for the supporting columns 4 and gives stability to the whole base when it is installed on the seabed.

The design of the bottom 3 of the base provides for the presence of ballast 7 at its bottom to increase the weight in order to obtain the necessary stability of the entire base. The inner cavity of the lower part 3 is divided into five waterproof compartments and each compartment has its own remote controlled kingston from the top / bottom platform.

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Hollow support columns 4 serve not only as opars for the upper part t of the base, but also as pipelines for injecting air into the compartments of the barge and ejecting water from the latter when the barge ascends. For this purpose, all the upper ends of the columns are sealed tightly and connected by appropriate pipelines to valves that are remotely controlled.

The auxiliary pontoons 2 located between the top part and the bottom part 3 of the base are intended to keep afloat in a horizontal position of the top part of the base when the bottom part 2 sinks or floats. The pontoons 2 also have a pipeline in the form of a vertical column 8 (Fig. 2), which passes through the upper part of the base and serves to force air into the pontoons during ascent.

Auxiliary pontoons are fitted with kingstones for flooding, which are controlled from the top / base site.

In the floating state {fig. I) the upper part / bases, the auxiliary pontoons 2 and the lower part 3 of the base are pressed together, and the draft of the barge of the lower part 3 of the base is determined by the weight of the entire system. In such a floating state, the support columns 4 rise above the platform of the upper part of the base and are rigidly connected to each other. The height of the supporting columns is made depending on the maximum depth of the sea for which the base is intended.

When the bottom part 3 of the base is immersed on the seabed, and then the auxiliary pontoons 2 are immersed, the weight of the top / base is transferred to the supporting columns 4.

To transfer the movable base from the floating state to the stationary, the lower part of the 3 base is first immersed, for which the bookstones of the latter and the compartments of the floor are opened: they are washed with sea water.

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as a result, the bottom 3 of the base gradually increases the draft, loses its buoyancy and sinks to the seabed.

From the moment when the bottom part 3 of the base begins to sink, the auxiliary pontoons 2 lower and take on themselves the entire weight of the upper part 1 of the base with equipment, acquiring the maximum draft when the bottom part of the base is fully submerged.

When the latter is on the seabed, sub-pontoon compartments are flooded by opening the corresponding kingstones. When submerging the pontoons 2, the middle row of columns 4 serves as a direction for them.

After immersion, the auxiliary pontoons 2 of the vehicle are on the lower part of the 3 bases, increasing the stability of the entire structure. At the same time, they carry along with them a movable tubular column 8, through which the subsequent air is pumped when the auxiliary pontoons are raised.

With the immersion of the auxiliary pontoons 2, the entire upper part of the base is automatically fixed on the supporting columns 4 as a result of the fact that the upper part of the base begins to slide down along the supporting columns.

To secure the upper part 3 on the supporting columns 4, the movable base is equipped with a fixing device 6. After this, the bottom is an annular body .5, equipped with wedge cams 10 with shanks // (Figs. 3, 4). The shanks 11 are inserted into the shaped cuts of the rotary ring / 2, which consists of two halves and by means of the rollers 13 freely turning on the housing 9. The rotation is performed using the lever 14t connected to the rod 15 of the hydromechanical control. The rod / 5 on the one hand is provided with a piston 16, and on the other hand a washer 17, on which a spring 18 acts.

The rod 15, with the piston 16 n by the washer 17, moves in the cylinder 19 connected via the bracket 20 inadvertently with the housing 9. The latter is arnirno connected through the yoke 1 with the ring 22, which is screwed on the upper / base fitting 23.

When the ring 12 is rotated, the cams / O move apart or move, depending on which way the lever 14 is turned. In this case, all the cams move simultaneously because the shanks // enter into the same shaped cuts on the inner surface of the ring 12.

Under the action of the spring 18, the lever 14 rotates the ring so that all the cams tend to move apart, i.e., release the support column 4. When oil is pumped into the cylinder 19, the latter presses on the piston // and, compressing the spring, turns lever 14, and therefore and the ring 12 to the other side so that all the cams approach the support column and are pressed against it.

If such an action took place at the moment when the weight of the upper part of the base is transferred to the housing 9 and, therefore, to the cams 10, then the latter will even more grip the supporting column 4. When mounting the whole base, this happens at the moment of submerging the auxiliary pontoon 2. Control The hydraulic mechanism of the clamping device is made from the common control panel.

When the upper part / base transfers its weight to the supporting columns 4, further immersion of the pontoons 2 will separate them from the upper part and they will be loaded onto the barge.

Thereafter, diagonal braces 24 are installed between the upper part of the base and the lower part, which create rigidity to the whole system and the transverse bolt 25 is removed connecting the supporting columns 4 of the base.

Subject invention

Claims (3)

1. A mobile base for offshore drilling using a submerged barge as the bottom of the base, distinguished by the fact that a pontoon is placed between the upper part of the base and the flooded barge designed to keep the upper part of the base in a horizontal position. 2. A movable base according to claim 1, characterized in that an annular body connected to the upper base nozzle, carrying wedge cams 10 with shanks 11, which enter the curved cuts of the swivel ring 12, is used to fill the upper base part on the supporting columns of the flooded barge. the purpose of the vertical movement of the wedge cams for clamping or releasing the support column. 3. The form of the apparatus according to claim 2, characterized in that a hydraulic mechanism is used to rotate the ring 12. five “RF Lrxrxmn  chg jl / IIT; ., | f- ;, FIG. 3 FIG. four