JPH01169011A - Casing guide apparatus, bushing device and method of constructing water bottom oil field - Google Patents

Abstract

PURPOSE: To enable relative vertical movement of a template and a casing in an oil extraction port by operatively connecting the template in which an oil extraction port is formed and a cylindrical oil extraction casing inserted in the oil extraction port. CONSTITUTION: A template housing 62 of a template 12 and an oil extraction casing 32 are operatively coupled to each other to enable relative vertical movement between the template 12 and the oil extraction casing 32, and inhibit relative lateral movement in an oil extraction port 44. The templates 12 are arranged to form a steel grid structure 42.

Description

TECHNICAL FIELD OF THE INVENTION This invention relates to the construction of underwater oil fields, and more particularly to a casing guiding device for connecting an oil extraction casing to a gravity-based anti-template.

BACKGROUND OF THE INVENTION As hydrocarbon reservoirs on land and on the shallow ocean floor become scarcer, the search for petroleum reserves is extending deeper into the Earth's land shelves. As reservoirs are found in these deeper waters, more complex and sophisticated construction systems are being developed. In the near future, offshore exploration and construction will be required to occur at depths of 10,000 feet or more. Subsea discovery compaction construction is limited for use on the ocean floor deeper than 1,200 to 1,500 feet due to the required vertical size of the equipment, so other specialized equipment is It is being developed.

One such specialized device is a tension leg platform (TLP). The TLP comprises a semi-submerged pull 70-tengue platform moored to the seabed by vertical members, ie mooring lines referred to as tension legs. By ensuring that the buoyancy of the TLP is greater than its operating weight under all environmental conditions, the tension leg is maintained under a predetermined tension at all times. This TLP also ensures that vertical movements such as heap, pitch, and ball are limited by the tension legs, while lateral movements that allow for sway, surge, and yaw are also limited. .

In the first TLP, constructed at a depth of 485 feet in the north-south Hallaton Field, separate A piled mooring template is used. Another anti-template is provided on the seabed.

The use of a gravity-based anti-template is required for the mooring of the TLP and to serve as a guiding template for the well located below the TLP.

This gravity-based anti-template has a rigid configuration that is placed on the seabed by gravity, rather than an oil-retained pile.

PROBLEM SOLVED However, a suitable gravity-based anti-template aspect is
There is a problem in that during the operational life of this family of templates, the templates have to become larger and gradually immerse into the ocean floor.

It is therefore an object of the present invention to be used in conjunction with a gravity-based anti-template to allow the installation of a gravity-based anti-template downwards to a casing extending upwardly from the well, and for casings passing through the family template. It is an object of the present invention to provide a casing guide device that provides lateral support for the casing.

SUMMARY OF THE INVENTION A casing guiding device of the present invention is operatively connected between a group template and a extraction casing and is configured to control relative vertical movement of the group template and extraction casing at the extraction port. Bushing means is provided to prevent lateral movement. As a result, no compressive load is applied to the upper part of the casing, making it possible to install the group template in the water bottom relative to the casing, and preventing the upper part of the casing from curving when the group template is installed. Ru.

In the embodiment, the bushing means includes a bushing member having a cylindrical bushing hole into which the oil extraction casing is tightly inserted. Further, the bushing means operatively connects the bushing member and the oil sampling port of the group template, and when the oil sampling casing and bushing are lowered and inserted into the oil sampling port of the group template, the bushing member is inserted into the oil sampling port of the group template. The embodiment includes a locking means that is engaged with a predetermined location of the device.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS As shown in the accompanying drawings, and in particular in FIG. 1, a tension leg platform (TLP) 10 is tethered to a gravity base, a family template 12, by a plurality of leashes 14.

The family template 12 is installed on the seabed 16 defining the bottom of the ocean 18 . Said tension leg platform 1
0 is floating on the sea surface 20.

The tension leg platform 10 has a work deck 22 supported on four corner posts 24 connected to each other by horizontal floats 26.

A plurality of oil extraction risers 28 extend from a seabed oil extraction head 30 provided at the upper end of an oil extraction casing 32 . Each oil extraction riser 28 has an oil extraction head device 3 installed on the work deck 22 and generally referred to as a Christmas tree.
Connected to 4.

2 and 3 are a plan view and a sectional view of the group template 12. FIG. Family template 12 like this
U.S. Application P840.235, filed March 17, 1986.
It is written in

The group template 12 is mainly made of reinforced concrete, and as shown in FIG.
Four corner posts 24, eight small storage tanks 36,
It includes four large storage tanks 38, a connection wear 40, and a steel grid structure 42 in which a plurality of oil extraction ports 44 are formed.

The concrete portion of the family template 12 has a skirt pile 116 extending downwardly from the outer periphery, which is projected into the seabed 16 when the family template 12 is installed on the seabed 16.

An anchor template 46 to which the lower end of the tether 14 is anchored is provided on the upper surface of each corner post 24.

In FIG. 3, one of the oil extraction casings 32 is shown, the lower end 48 of which is secured within the oil extraction hole 52 by cement 50. An upper end 54 (upper unsupported portion) of the oil extraction casing 32 protrudes from the oil extraction hole 52 and extends upwardly from the seabed 16 to the steel grid structure 42 . The upper end 54 of this extraction casing 32 passes freely through a lower conductor grid 55 and an intermediate conductor grid 57, which are respectively supported on the frame 59, 61 of the family template 12. These grids 55.57 as well as frames 59.61 are shown in a simplified manner in FIG.

FIG. 4 is an enlarged cross-sectional view of a portion of FIG.
The steel grid structure 42 is shown in detail.

The steel grid structure 42 includes upper and lower horizontal members 56,58 connected to each other by vertical members 60.
has.

The oil inlet 44 is defined in a cylindrical template housing 62, which is supported on upper and lower horizontal members 56,58 via short horizontal members 64 and diagonal members 66.

Each housing 62 is centrally located in each of four guide posts 68 that, when brought down from the tension leg platform 10 into the drag and template 12, contain oil extraction casings. A guide line (for use in a guiding cylindrical member such as 32)
(not shown) are connected.

FIG. 5 shows a steel grid structure 42 of family template 12 directly surrounding one of template housings 62.
A portion thereof is partially enlarged and shown together with the upper end of the oil extraction casing 32 and the connection means between the oil extraction casing 32 and the family template 12. The extraction casing 32 is typically a 30 inch diameter casing.

As shown in FIG. 5, bushing means 68 are operatively coupled to template housing 62 of family template 12 and extraction casing 32 to permit relative vertical movement between family template 12 and extraction casing 32. At the same time, relative lateral movement between the group template 12 and the oil extraction casing 32 at the oil extraction port 44 is prevented.

The bushing means 68 includes a cylindrical bushing member 70 having a cylindrical inner bushing hole 72 into which the oil extraction casing 32 is tightly inserted. This bushing member 70 is preferably comprised of two half-cylindrical members connected together around the uppermost portion of the extraction casing 32. Further, the bushing member 70 is made of a material that forms a cathode with respect to the material of the group template 12.

The bushing member 7o has a tapered lower end 71 so that it is prevented from lifting when it is lowered and inserted into the template housing 62. The bushing member 70 also has an annular lip 73 at its upper end that projects radially outward.

The bushing means 68 also includes a bushing member 7.
0 and the oil extraction port 44 of the family template 12, the oil extraction casing 32 as well as the bushing means 6
8 is lowered and inserted into the oil extraction port 44, the oil extraction port 4
The bushing member 70 has latch means 74 for locking the bushing member 70 in a predetermined position within the bushing member 4.

The oil extraction port 44 is defined by a cylindrical housing ring of the template housing 62.

The latching means 74 have upper and lower latching annular grooves 76, 78 respectively formed in the tap 44.

Said latching means 74 also have radially outwardly biased upper and lower locking means 80 , 82 connected to and radially outwardly biased from the bushing member 70 . and are inserted into the upper and lower latch annular grooves 76, 78, respectively.

The upper latch annular groove 76 allows the lower locking means 82 to
The Taber annular lower surface 77 passes through this and goes downward.
has.

The family template 12 also has a conical guide means 84 provided on the oil extraction port 44 coaxially with the oil extraction port 44 and having an open upper end. Furthermore, a conical guide means 85 with an open lower end is installed so as to extend below the oil extraction port 44, thereby preventing bits, reamers, etc. that are moved upward through the oil extraction port 44 from being caught. Ru.

The bushing member 70 is attached to the template housing 62
It has a cylindrical outer surface 86 that comes into close contact with the oil extraction port 44 of the oil extraction port 44 .

The upper and lower locking means 80 and 82 shown in FIG.
It may be comprised of an expandable snap ring supported on the upper and lower sides formed on the outer surface 86 of the bushing member 70.

A releasable connection means 100 is operatively coupled to the oil extraction casing 32 and the bushing member 70 such that the bushing member 70 is in the fixed position shown in FIG. Vertical movement of the bushing member 70 relative to the extraction casing 32 is restricted until the bushing member 70 is engaged. This connecting means 100 is preferably constituted by means that initially prevent substantial vertical movement of the bushing member 70 relative to the extraction casing 32, but also with a slight restricted movement of the bushing member 70 relative to the extraction casing 32. It may be configured to allow movement.

In the embodiment shown in FIG. 5, the connection means 100 is constituted by a plurality of shear pins 102, 104 connected between the oil collection casing 32 and the bushing member 70.

The oil extraction casing 32 has a sleeve 106' fixed thereto, and a sleeve 106 positioned below the sleeve 106' and provided tightly but slidably on the oil extraction casing 32. These sleeves 106
．． 106' together define a cylindrical outer surface 10B. One sleeve 106' is tightly inserted into bushing hole 72 and has sufficient strength to prevent lateral movement of oil extraction casing 32 relative to bushing member 70. However, the insertion of the sleeve 106' into the bushing hole 72 is such that vertical sliding of the oil extraction casing 32 and the sleeve 106' relative to the bushing member 70 is possible.

Preferably, one sleeve 106' is formed of metal or a highly elastic compound that is shrink-fitted or glued to the extraction casing 32, and the other sleeve 106 is made of a metal or a highly elastic compound that is shrink-fitted or glued to the extraction casing 32. It may be formed by similar members that simply fit tightly. The use of two sleeves 106° and 106' is to obtain a more concentric outer surface compared to known typical casings.

The sleeve 106 is located below the tapered lower end 71 of the bushing member 70 and has a tapered lip 109 that protrudes radially outward.
As the bushing member 70 is moved downwardly and inserted into the template housing 62, the bushing member 70 is prevented from becoming hooked and the external member is prevented from making unnecessary contact with the bushing portion 470, causing the shear pin 102. 104 is prevented from deforming initially.

The shear pins 102 and 104 have their radially inner ends welded to the outer surface 110 of the oil extraction casing 32, and their outer ends.
It passes through the sleeve 106' and engages in a radial blind hole drilled in the bushing hole 72.

A method of using the casing guide device having the above configuration will be explained below.

First, the anti-template 12 having the oil extraction port 44 is attached to the seabed 1.
6. Install on top.

Next, the bushing means 68 is assembled with the oil extraction casing 32 and moved downward from the TLPIO to penetrate the oil extraction port 44 until the lower part 48 of the oil extraction casing 32 enters the oil extraction hole 52.

When the oil extraction casing 32 and the bushing means 68 are lowered and inserted into the oil extraction opening 44 of the anti-template 12, the upper and lower locking means 80,82 lock the oil extraction opening 44.
7m above and below formed! 76 , 78 , so that the bushing means 68 engages with the anti-template 12
The oil extraction casing 32 is prevented from moving laterally within the oil extraction opening 44 relative to the anti-template 12. When the oil extraction casing 32 and the bushing means 68 are in the lowered position, the bushing means 68 is fixedly held to the oil extraction casing 32 by the connecting means 100.

The engagement of the bushing means 68 with the anti-template 12 by the connecting means 100 as shown in FIG.
2.104 and can be released by vertically sliding the anti-template 12 together with the sleeve 106' within the bushing hole 72. When the sleeve 106 abuts the bushing member 70, it can be slid down relative to the extraction casing 32 as required.

The lower part 48 of the oil extraction casing 32 is fixed within the oil extraction hole 52 by cement 50. During the activation cycle of the family template 12, the family template 12 is gradually immersed and installed into the seabed.

In some cases, this immersion extends to approximately 10 inches over the operational life of family template 12.

In the family template 12, the seabed 1 shown in FIG.
6 to the steel grid structure 42, the length of the upper unsupported portion 54 of the extraction casing 32 is on the order of 30 to 50 meters. Therefore, if the group template 12 is secured to the oil extraction casing 32 at the extraction port 44, the compressive load applied to the upper unsupported portion 54 of the oil extraction casing 32 during installation of the family template 12 will cause the oil extraction casing to The unsupported portion 54 of 32 may be curved.

However, in the bushing means 68 according to the present invention, no substantial compressive load is applied to the unsupported portion 54 of the oil extraction casing 32, and the family template 12 can be immersed into the seabed relative to the oil extraction casing 32. Therefore, there is no possibility that the unsupported portion 54 of the oil extraction casing 32 will curve.

At the same time, however, strong lateral support is required for the extraction casing 32 at the extraction opening 44.

As shown schematically in FIG. 3, the upper end 112 (FIG. 5) of the extraction casing 32 is connected to one of the extraction risers 28 by a connector 114.

As is well known in this field, oil extraction riser 28
receives substantial lateral forces due to the tidal currents and movement of the family template 12. Therefore, if the extraction casing 32 is not rigidly secured against variable movement at the extraction opening 44 formed in the steel grid structure 42 of the family template 12, the extraction riser 28 Due to dynamic response, oil extraction casing 3
2 and the grid structure 42, a potentially damaging impact occurs. Furthermore, the dynamic forces are transmitted to the unsupported parts 54 of the extraction casing 32 as well as other annular members in the extraction casing 32, which become fatigued over time.

The bushing means 68 according to the invention can provide the necessary lateral support and also
The family template 12 can be installed submerged in the seabed without placing dangerous compressive loads on the upper unsupported portion 54 of the template 2.

[Brief explanation of the drawing]

FIG. 1 is a schematic side view of the TLP moored to the anti-depression plate, FIG. 2 is a plan view of the family template, and FIG. 3 is a cross-sectional view of the family template along line 3-3 in FIG. , FIG. 4 is an enlarged view showing a part of the anti-tembray 1 into which the upper part of the oil extraction casing has been inserted and the lower part of the oil extraction casing fixed to the seabed, and FIG. 5 is an enlarged view of the casing according to the embodiment of the present invention FIG. 2 is a partially sectional and enlarged side view of the upper part of the oil extraction casing inserted into the group template to show the guide device in detail. DESCRIPTION OF SYMBOLS 10... Tension leg platform, 12... Group template, 28... Oil extraction riser, 32... Oil extraction casing, 34... Oil extraction head device, 43... Grid structure, 68... Bushing Bushing means, 70... Bushing member, 80, 82... Locking means, 100
...Releasable connection means. Applicant's representative Patent attorney Takehiko Suzue FIG, / FIG, 4

Claims (1)

[Scope of Claims] 1. An anti-template having an oil extraction port formed therein, a cylindrical oil extraction casing inserted into the oil extraction opening, and operatively connected between the anti-template and the oil extraction casing, A casing guide device characterized in that it comprises bushing means for allowing relative vertical movement of the anti-template and the oil extraction casing at the oil extraction opening and for preventing lateral movement. 2. The anti-template is a gravity-based anti-template that gradually sinks into the water bottom during its operating life, and the oil extraction casing has a lower part fixed in the water bottom and protrudes from the water bottom through the oil extraction port. and a bushing means that allows the anti-template to be installed in the bottom relative to the extraction casing without imposing a substantial compressive load on the upper part of the extraction casing. A casing as claimed in claim 1, characterized in that it is configured so as to prevent the upper part of the extraction casing from curving when the anti-template is installed. Guidance device. 3. The bushing means operatively connects a bushing member having a cylindrical bushing hole into which the oil sampling casing is tightly inserted, and the oil sampling port of the anti-template, and The invention further comprises a locking means for engaging the bushing member at a predetermined position within the oil-sampling port when the casing and bushing means are lowered and inserted into the oil-sampling port of the anti-template. Casing guide device according to paragraph 1. 4. The anti-template has a template housing having a housing hole defining the oil extraction port, and the locking means is connected to an annular engagement groove formed in the housing hole and the bushing member; The casing guide device according to claim 3, further comprising an engagement member that projects further radially outward and is inserted into and engaged with the engagement groove. 5. The casing guide device according to claim 4, wherein the anti-template further has a conical guide means disposed coaxially with the housing hole and opening upward. . 6. The casing guide device according to claim 4, wherein the bushing member has a cylindrical outer surface that is tightly inserted into the housing hole of the template housing. 7. operatively connected to the annulus of the oil extraction casing and the bushing member and causing an initial vertical movement of the bushing member relative to the oil extraction casing until the bushing member is fixed in position within the oil extraction opening of the anti-template; Casing guide device according to claim 3, characterized in that it has restricting and releasable connection means. 8. The casing guide device according to claim 7, wherein the releasable connection means is configured as a means for initially preventing vertical movement of the bushing member with respect to the oil extraction casing. . 9. The casing guide device according to claim 8, wherein the releasable connection means includes a plurality of shear pins connecting the oil extraction casing and the bushing member. 10. The oil extraction casing has a sleeve fixed thereto defining a cylindrical outer surface, and the sleeve is tightly inserted into the bushing hole to prevent substantial vertical movement of the oil extraction casing relative to the bushing member. The casing guide device according to claim 3, wherein the oil extraction casing and the sleeve can be moved vertically with respect to the bushing member. 11. A cylindrical bushing member having a cylindrical bushing hole into which the oil extraction casing is slidably inserted; operatively connected to the bushing member and engaged with the anti-template; locking means for engaging the bushing member at a predetermined location within the oil well opening when the casing and the bushing means are lowered and inserted into the oil well opening of the anti-template; releasable connection means connectable to the extraction casing and restricting initial vertical movement of the bushing member relative to the extraction casing until the bushing member is fixed in position within the extraction port of the anti-template. A bushing device characterized by: 12. The bushing device according to claim 11, wherein the releasable connection means is configured as a means for initially preventing vertical movement of the bushing member with respect to the oil extraction casing. . 13. The bushing device according to claim 12, wherein the releasable connection means includes a plurality of shear pins connecting the oil extraction casing and the bushing member. 14. A patent characterized in that the locking means has an engaging member connected to the bushing member, protruding radially outward from the bushing member, and capable of engaging with an engaging groove formed in the anti-template. A bushing device according to claim 11. 15. (a) placing an anti-template having a bushing hole therein at the bottom of the water; combining the bushing means with the oil extraction casing; and (c) inserting the lower part of the oil extraction casing into the oil hole. (d) lowering the oil extraction casing through the oil extraction port of the anti-template until the oil extraction casing is fixed to the anti-template;
(e) fixing a lower part of the oil extraction casing in the oil hole; effecting downward movement of the bushing means relative to the extraction casing as the template is recessed, thus preventing curvature of the upper part of the extraction casing when the anti-template is installed. A method for constructing an underwater oil field characterized by: 16. said step (b) is characterized in that said bushing means and said oil extraction casing are releasably connected, thus limiting the initial vertical movement of said bushing means relative to said oil extraction casing, and said step (d) 16. The method for constructing an underwater oil field according to claim 15, further comprising the step of releasing the bushing means and sliding it along the oil extraction casing. 17. The method for constructing an underwater oil field according to claim 16, wherein the step (b) is to prevent initial vertical movement of the bushing means with respect to the oil extraction casing. 18. The method for constructing an underwater oil field according to claim 18, wherein in step (b), the bushing means and the oil extraction casing are connected brittle with a plurality of shear pins. 19. The method for constructing an underwater oil field according to claim 16, wherein the releasing step deforms the shear pin by applying a vertical force to the oil extraction casing. 20. The method for constructing an underwater oil field according to claim 15, wherein in the step (e), the lower part of the oil extraction casing is fixed in the oil hole with cement.