JPS61150889A - Tallet supporting structure for tallet mooring vessel - Google Patents

Abstract

PURPOSE:To prevent occurrence of jumping by installing a plurality of supporting rollers on the deck in such a way as surrounding a through hole for insertion of tallet, by furnishing press rollers alongside a circumference of this through hole parallelly as up and down, and by supporting the upper flange and side of the tallet in contact with the rollers. CONSTITUTION:A plurality of supporting rollers 5 are furnished on the deck 4 of a hull in such a way as surrounding a through hole 3 for insertion of tallet 2, to support the flange part 201 of the tallet. Press rollers 6a, 6b are installed alongside a circumference of said through hole 3 parallelly as up and down to restrain the upper and lower parts of the tallet in their circumferential directions. This can effectively prevent the tallet from tilting, so-called jumping phenomenon, likely to occur when the hull makes displacement during mooring.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a turret support structure in a turret muling ship.

[Conventional technology]

Undersea oil fields are being developed around the world in deep water areas, areas with poor sea conditions, or areas that have been neglected due to low reserves.
So-called turret muling vessels, which are easy to move and install, are attracting attention. This ship has a hull (
The turret (2), which is cylindrical and has a flange (201) (decker part) on the outer side of the upper part, is inserted into the through hole (3) formed through the center of the vessel (1), and the through hole on the hull is inserted into the through hole (3). A bearing device consisting of a plurality of support rollers (7) that can be raised and lowered is provided around the periphery, and the turret (2) is rotatably supported by the bearing device via its flange (201). The structure includes multiple sets of mooring devices consisting of mooring ropes and anchors (1).

This vessel lowers mooring lines (6) and anchors (7) radially from the turret, permanently mooring the turret (2) directly above the oil well, and performs drilling etc. using an oil country pipe lowered through the inside of the turret (2). The outer hull of the turret is designed to respond to the influence of tidal currents, etc. In reality, depending on the water depth of the floating location and sea conditions, the turret (2) moored with a mooring device is On the other hand, by using a bearing device, the hull side can be made to turn freely, so that the effects of tidal currents etc. can be absorbed by the hull side, or by lowering the entire bearing device, the turret (2) (
The flange (201)) is placed on the hull, and when the mooring cables extending radially in all directions from the turret (2) are twisted by a certain degree due to the turning of the ship due to tidal currents, etc., the turret (201) is placed on the hull. 2) Raise the bearing device so that it can rotate,
A correction is made to return the turret (2) to rotation while braking the rotation with the braking device so that the twist in the mooring cable is restored.

In such a ship, a horizontal force based on the tension of the mooring line acts on the turret (2) as the ship sways back and forth, causing the turret to tilt, a so-called jumping phenomenon, which causes the turret to be supported. There is a problem in that an uneven load acts on the bearing device. Conventionally, in order to prevent this kind of jumping, through holes (3
) A bearing device consisting of a plurality of presser rollers (C) for pressing the upper surface of the flange (201) is attached via a support frame (2).

[Problem that the invention seeks to solve]

However, the conventional jumping prevention mechanism as described above
There is a problem that the support structure for the presser roller (goods) via the support frame (2) is complicated, and the mooring rope (towards)
The point of action of the horizontal component force from the turret is the lower end of the turret, whereas the mechanism for preventing jumping restrains the upper end of the turret, which is separated from the above point of action. (6) is in a sideways state, so if the horizontal force acting on the turret is large, there is a problem in that it is difficult to avoid the occurrence of some jumping.

The present invention has been made to solve these conventional problems, and aims to provide a structure that is simple and can appropriately suppress the jumping of the turret.

[Means and effects for solving the problem] For this reason, the present invention provides a plurality of support rollers on the hull deck so as to surround the through hole for inserting the turret, and the support rollers allow the turret to be inserted through its collar. I will make it supportable.
A plurality of presser rollers are provided at each position on the upper and lower parts of the hull along the circumferential direction of the through-hole to abut on the side of the turret, so that the group of presser rollers restrains the upper and lower parts of the turret in each circumferential direction. Its basic feature is that it has

According to such a structure, the upper part of the turret and the lower part of the turret, which are the application points of horizontal component forces, are restrained in the respective circumferential directions by the pressing rollers, so that jumping of the turret is appropriately prevented.

〔Example〕

FIGS. 1 and 2 show an embodiment of the present invention. On the deck (4) of the hull (1), a plurality of support rollers ( A group of supporting rollers constitutes a bearing device for supporting the turret.The turret (2) is inserted into the through hole (3), and the upper flange (
201) (the lower surface of the collar), the plurality of support rollers (
It can be supported by a bearing mechanism consisting of five bearings.

Rotatable presser rollers (61) (6b) to be in contact with the sides of the turret (2) are installed at each position in the upper and lower parts of the hull.
A plurality of (horizontal rollers) are provided along the circumferential direction of the through hole, and the upper and lower pressing roller groups restrain the upper and lower circumferential directions of the turret (2). There are presser rows (6 m) on the outer circumferential surfaces of the upper and lower parts of the turret (2).
Rails (7a) and (7b) are provided against which b) should roll against.

In addition, as described later, the turret (2) is supported by a support roller (5).
) can be raised and lowered by raising and lowering the rails (6a) and (6b).
7a) It can be slid in the width direction of (7b).

FIG. 2 shows the physical structure of the support roller,
The support roller (5) is configured to be movable up and down, supports the turret (2) in an upper position, and supports the turret collar (201) in a lower position on a support stand (not shown) on the hull. In this embodiment, 1
A pair of support rollers (5) are provided at the location.

A support body (9) is vertically fixed to a mounting base (8) on the hull (1), and support rollers (5) are arranged on both sides of the support body (9).

Each support roller (5) is rotatably attached to the middle part of the frame body αO, and one end of each frame body αO is pivotally attached (2) to the support body (9).
The main body of the cylinder device (6) is pivoted on both sides of the cylinder device (8), and the upper end of the rod (121) of each cylinder device (6) is connected to the other end of each frame body. As a result, each support roller (5) is rotated by the operation of the cylinder device (6) and is raised and lowered t.

In order to absorb damage and errors in manufacturing accuracy, a presser roller (6
m) It is preferable that (6b) is also supported by a cylinder device in the same way as shown in FIG. 2, and configured to be horizontally movable (moveable in the direction of the turret). As a result, the circumferential pressing rollers (6a) and (6b) can securely restrain the turret (2).

Furthermore, a storage space αη for storing the mooring cable is provided between the outer plate (to) and the inner plate CTF3 of the turret (2), and this storage space aη is arranged vertically in the circumferential direction of the turret. A guide pipe (not shown) for mooring cables is provided, and a winch (not shown) for winding up the mooring cables is provided above the turret. The mooring cable stored in the storage space is guided upward and guided toward the lower end of the turret through the guide pipe via a winch, and the anchor is dropped from the lower end of the turret.

A ship with the above structure is moored by lowering the mooring cables and anchors radially in all directions from the lower end of the turret at the planned mooring point, and the turret (2)
The oil country tubular goods are lowered to the seabed side through the space α4 inside and the work is carried out.

During such mooring, a horizontal force based on the tension of the mooring line acts on the turret (2) due to the horizontal shaking (displacement) of the hull (1), causing the turret (2) to move toward the hull (1).
), but since the turret (2) is restrained by presser rollers (6m) (6b) in the circumferential direction at the lower and upper positions, which are the application points of the horizontal component of the turret (2), the turret ( 2) Inclination, that is, jumping, is appropriately suppressed.

〔Effect of the invention〕

According to the present invention described above, since the upper position of the turret in the circumferential direction and the lower position of the turret in the circumferential direction, which is the point of action of the horizontal force that causes the turret to tilt, are restrained by the press rollers, jumping of the turret is appropriately prevented. Furthermore, there is no need for a complicated presser roller support structure as in the prior art, and there is an advantage that the structure can be simplified.

[Brief explanation of the drawing]

1 and 2 show an embodiment of the present invention, in which FIG. 1 is a longitudinal sectional view, and FIG. 2 is a view taken along the line ]-■ in FIG. FIG. 3 is an explanatory diagram showing a conventional turret muling ship. In the figure, (1) is the hull, [2] is the turret, and (3)
(5) is a support roller, (6a) and (6b) are press rollers, and (201) is a flange.

Claims (1)

[Scope of Claims] A plurality of support rollers are provided on the hull deck so as to surround the through hole for loading the turret, so that the support rollers can support the turret through its collar, and the upper part of the hull A plurality of presser rollers are provided along the circumferential direction of the through hole at each position of the turret and the lower portion thereof, and the presser rollers restrain the upper and lower portions of the turret in each circumferential direction. Turret support structure on a turret-maring ship.