RU1821526C - Offshore oil production platforms - Google Patents

Abstract

Use: in offshore stationary platforms for oil and gas production, installed on the seabed in the continental shelf in areas with high seismicity and with difficult ice conditions. Essence: the platform is equipped with ogfg / .1 coring structure, made in the form of a set of ring elements. Each of the ring elements B and 9 is made covering the base part, hollow with a margin of buoyancy and composing of sections 10 and 11. The ring elements are mounted on top of each other, above the ballast tank and relative to the base part with gaps .12, in which spring shock absorbers are built 13. Each of the elements supporting the deck superstructure on the base part is made in the form of a metal building frame structure 14. The metal structures are placed with gaps 15 between concentric partitions, equipped with seismic protection foundations, n For example, in the form of swinging posts 16 and connected to partitions through vibration dampers 17.1 zp 5-yl, 5 & o ate Os

Description

The invention relates to construction and can be used in offshore stationary platforms for oil and gas production, installed on the seabed in the continental shelf in areas with high seismicity and with difficult ice conditions.

The purpose of the invention is to increase the reliability of the platform under the action of dynamic loads on it,

And FIG. I shows the platform in section (the dashed line shows the process equipment); on FIG.2 - section along aa of figure 1; in Fig.3, 4 and 5 - fragments of a General view on an enlarged scale,

The proposed platform is arranged as follows. It includes a foundation plate T, a hollow base part, divided by concentric 2 in plan and horizontal 3 partitions into ballast 4 and oil storage tanks 5, as well as a deck superstructure b with support elements on the base part and with the technological equipment located 7.

The platform is provided with a building envelope, which is made in the form of a set of annular elements 8 and 9, covering the base part. The set of annular elements is a truncated pyramid. Each of the annular elements is hollow with a buoyancy margin and stacked of sections 10 and 11. The annular elements are mounted one above the other, above the ballast tanks 4 and relative to the base part with gaps 12. Spring shock absorbers 13 are built into the gaps.

The supporting elements of the deck superstructure on the base part are made in the form of metal structures of frame buildings 14, which are placed with gaps 15 between. concentric partitions / and are equipped with seismic protection foundations, for example, in the form of swinging racks 16. Vibration dampers 17 are built into the gaps 15, The gap 12 between the ring element 8 and the base part above the water line 18 is thermally insulated by the fence 19 and mountains are fed into it gas, e.g. associated gas combustion products. The access of cold air to the residential and office rooms located inside the frame buildings 14 is closed with the help of the fence 20, which insulates the gap between the deck superstructure and the external concentric partition. Pos. 21 are marked ice floes and item 22 is a stone outline around the base.

The platform of the invention operates as follows in various situations.

Situation 1 - strong wave impact. In this case, the shock of the waves occurs mainly on the annular element 8. The annular element 8 due to its massiveness, supplemented by a certain mass of water, and being in a submerged state

0 has a significant inertia and this circumstance allows it to take on and extinguish a significant part of the energy of the wave action on the platform as an anvil. With prolonged

5 of the wave action in the same direction, the annular element 8 is displaced and is in contact with the spring shock absorbers 13, which also begin to participate in the damping of the energy of the wave action. At

In this case, particularly powerful wave impacts are transmitted to the base part of the platform. However, due to the seismic protection foundation (swinging posts 16) and vibration dampers 17, the supporting elements of the base part - the metal structural structures of frame buildings 14 and the deck superstructure - practically do not experience impacts and shocks.

Situation 2 - ice action caused by impacts of individual ice floes carried away by the current and wind is also perceived by the ring elements 8 and is extinguished similarly to situation 1.

Situation 3 - ice impact caused by the sliding of ice onto the platform.

5 When sliding ice 21, energy is first consumed for some immersion of the ring elements 8 and 9 within the horizontal ... gaps 12 between the elements and between element 9 and ballast tanks, and

0

then compressing the spring shock absorbers

13. After all the possibilities of the heel rings, x elements are selected, the ice field begins to work on bending due to the conical shape of the elements and

5 crumble. In this case, a considerable shear force from the side of the ice floor to the platform is opposed by its mass, supplemented by ballast placed in the tank 4, as well as a stone draft 22, placed around the platform.

The movement of the ring element a 8 does not impede ice, which could have formed in the vertical gap 12 (Fig. 3), if heat insulation was not provided above the waterline and hot gases were supplied to it.

In case under pressure. created by the ice field, the wall of a separate section of the annular element was forced through, then, with favorable

in summertime, it is being replaced by another section, which will be towed to the platform in advance.

As the slide of ice 21 is weakened, the ring elements rise to the initial level and again become ready to accept both dynamic and static loads on the base part of the platform.

Situations 4-seismic impact is perceived by the base part and the foundation plate (they must be calculated for this impact) and is practically cut off from the technological equipment, as well as from residential and industrial premises located in buildings 14 due to the presence of seismic protection foundation in the form of swinging posts 16 and vibration dampers 17.

Situation 5 - the impact of adverse weather and climatic conditions on the staff is smoothed out due to the fact that residential and part of the production facilities are located between the concentric partitions 2 and are isolated from the effects of cold wind, rain, snow, etc. using the fence 20.

Thus, the analysis of the platform in various situations allows us to assume that with the help of the proposed technical solutions achieved:

increased seismic resistance of the platform;

reduction in the dynamic effects of ice and waves on it;

maintainability increase;

improving the comfort of life and work of the serving character in harsh climates,

All these effects obtained increase the reliability of the oil production platform. ,:

Claims (2)

1. An oil-producing platform, including a base plate, a hollow base part, divided by concentric planes and horizontal cross-sections, into ballast and oil storage tanks, and a deck superstructure with support elements on the base part, characterized in that, in order to increase reliability of the platform under dynamic loads acting on it, it is equipped with spring shock absorbers and a walling made in the form of a set of hollow ring elements forming in cross section a truncated pyramid, while the annular elements are mounted one above the other above the ballast capacity and relative to the base part with gaps in which spring shock absorbers are integrated, moreover, a gap; located between the upper annular element and the base part, it is thermally insulated above the waterline, each of the supporting elements of the deck superstructure on the base part of the platform is made in the form of a metal structure of a frame building with seismic protection foundations, while the metal structures are placed with a gap between concentric partitions and are connected to towns through vibration dampers moreover, the gap between the deck superstructure and the outer concentric partition is thermally insulated, 2. The platform according to claim 1, with the exception that its protective foundations are made in the form of swinging racks. Aa fit /. 4 fiё.5