JPH04151Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a bearing structure for a turret plug in a work boat, and more specifically, to a bearing structure for a turret plug in a work boat used for oil drilling or oil production. be.

[Prior art]

Generally, various types of oil drilling equipment are used, but in relatively small-scale oil fields, a floating type is used to improve the mobility of the equipment. Many of these floating production equipment are moored using turret plugs in order to reduce external forces such as wind waves and tidal currents and to improve maneuverability.

In this method, as shown in Fig. 6, an opening 2 is provided in the center of the hull 1 of the work boat, and a turret plug 4 having a moon pool 3 (vertical hole in the center) is placed inside the opening 2. At the same time, this turret plug 4 is rotatably supported with respect to the hull 1 by a thrust bearing 5 and a radial bearing 6. Then, the lower part of the turret plug 4 is connected to the mooring line 7.
The hull 1 is moored by connecting to an anchor (not shown), and a drilling rig (not shown) is lowered from the moonpool 3 to drill for oil.

When an external force is applied to the hull 1 of such a work boat from a different direction, only the hull 1 turns so that the influence is less.

By the way, in devices of this type, conventionally, both the thrust bearing 5 and the radial bearing 6 are composed of roller bearings, so it is very inconvenient to replace them when wear or damage occurs, that is, maintenance. In addition, it is difficult to follow manufacturing errors and structural deformation of the bearing portion. In addition, the small contact area makes it difficult to withstand large loads, and the inability to absorb impact forces poses many problems, including the risk of breakage.

On the other hand, a device for mooring a work vessel such as an oil drilling vessel at one point has been proposed in Japanese Patent Application Laid-Open No. 48-38203. However, in this device, a plug having a convex engagement surface that fits into the concave portion is rotatably provided in an opening having a bowl-shaped concave portion provided in the hull, a guide tube is provided in the center of this plug, and a guide tube is provided in the center of the plug. A device is disclosed in which a plurality of anchor chains are stretched around a guide tube. However, there is no description of a bearing structure that is easy to replace and can bear large loads like the present invention.

Furthermore, Utility Model No. 53-103055 was developed as a device that removably installed a radial or thrust bearing inside the cage.
No. 2 is proposed. However, this device uses a combination of a flat plate thrust bearing and a cylindrical radial bearing to support the rudder shaft. This can only be applied to small shafts. Also, measures to prevent uneven contact are only applied to thrust bearings.

A large work vessel such as an oil drilling vessel is a large floating body with a length of 100 to 300 meters, and the turret plug used to moor it at one point has a diameter of 6 to 18 meters. , it is a large structure with a height of 10 to 25 meters, and it is difficult to make a bearing of an integral structure.In addition, there are manufacturing errors in the turret plug and hull opening, and the amount of deformation due to external forces during operation. The problem is that it is too large to be absorbed between the bearings.

[Purpose of invention]

The present invention uses a simple mechanism bearing structure to absorb manufacturing errors and structural deformation, which are problems in the bearing structure of turret plugs used to moor large floating bodies such as oil drilling ships, resulting in less damage and easier maintenance. The present invention provides a device that can facilitate work. Furthermore, it is an object of the present invention to provide a device that is small in size and can withstand a large load.

[Summary of the idea]

The bearing structure of the turret plug according to the present invention to achieve the above-mentioned object is such that the turret plug has a thrust bearing provided in the upper part of the opening penetrating the hull of the work boat in the vertical direction and a radial bearing provided inside. The two bearings include a flat bearing seat, a bearing retainer placed on the bearing seat via a plate-shaped elastic material, and a bearing retainer mounted on the bearing retainer. The bearing module is composed of a flat plate-like self-lubricating bearing segment that is detachably supported, and a plurality of thrust bearings are arranged in a ring shape at intervals along the lower surface of the flange portion of the turret plug. The radial bearings are arranged circumferentially at intervals on the inner surface of the opening.

As mentioned above, bearing modules are arranged in a ring shape to form a thrust bearing, and they are arranged in a circumferential direction to form a radial bearing, so each bearing module can be manufactured with high precision. Adjustments during installation can be made individually, making it easy. Furthermore, fluctuations in bearing load due to structural deformation of the hull and turret plug caused by manufacturing errors or external external forces can be easily absorbed by the elastic material.

〔Example〕

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a bearing structure for a turret plug in a work boat according to the present invention will be described below with reference to FIGS. 1 to 5.

FIG. 1 is a plan view showing a part of the thrust bearing 5;
FIG. 2 is a perspective view showing a part of the radial bearing 6. FIG.

A turret plug 4 is inserted into an opening 2 passing through the hull 1.
The thrust bearing 5 for supporting the turret plug 4 is constructed by arranging bearing modules 8 in a ring shape at appropriate intervals on the deck below the flange of the turret plug 4. On one side, a plurality of bearing modules 8 having a structure similar to that described above are arranged at appropriate intervals in the circumferential direction in a horizontal plane.

The bearing module 8 used in the bearing is the third
As shown in Figures 5 to 5, a stopper 11 made of a square plate and having edges 10 on the four sides of the bearing seat 9 is removably attached with bolts 12, and a rubber pad is installed inside the stopper 11. A bearing retainer 14 is removably attached with bolts 15 via an elastic material 13 such as the like.

Edges 16 are provided on both the left and right sides of the bearing retainer 14, and presser fittings 17 having an angle θ are removably attached to the upper and lower sides of the bearing holder 14, respectively, with bolts 18. A bearing segment 19 formed in a plate shape is held by a metal fitting 17.

The bearing segment 19 is made of a self-lubricating bearing material, such as a carbon-based molded product or a bearing alloy in which tetrafluoride resin is embedded.

As described above, the thrust bearing 5 and the radial bearing 6 are constituted by the bearing module 8, and when the bearing module 8 is repaired, the bearing segment 19 is replaced. For example, if it becomes necessary to repair the radial bearing 6 placed underwater, the radial bearing 6 can be repaired by making the water shallower in the hull 1.
By positioning the bearing segment 19 on the water line and operating the bolt 18 to remove the upper holding fitting 17, the bearing segment 19 can be pulled out upward and replaced with a new one.

As mentioned above, since the turret plug 4 is a large structure, when repairing the radial bearing 6, a worker must descend into the gap between the opening 2 and the cylindrical portion of the turret plug 4. be able to.

[Effect of idea]

According to the bearing structure of the turret plug according to the present invention, the following effects can be achieved.

A. When installing the bearings 5 and 6 on the hull 1, the installation is completed by arranging and fixing the plurality of bearing modules 8 at predetermined positions, and it also makes it easier to eliminate manufacturing errors and adjust the bearing gap. can be carried out and accurate bearings can be constructed.

B The bearing retainer 14 that supports the bearing segment 19, which is the surface material of the bearing module 8, is supported via an elastic material 13 such as a rubber pad between the bearing seat 9 and the turret plug 4.
The deformation of the elastic material 13 absorbs the force borne by the bearing segment 19 that contacts the surface of the
Bearing loads can be averaged and an optimal design with a small safety factor can be achieved.
Bearings can be made smaller and lighter.

C. Since the bearing segment 19 has a flat plate shape, it can have a large contact area, can bear a large load, and can provide a bearing with excellent durability.

D. Due to the arrangement of independent bearing modules 8 at predetermined intervals around the turret plug 4, if the bearing segments 19 become worn and need to be replaced, the working vessel 1
It can be easily and easily replaced at any point of operation while it remains moored.

[Brief explanation of drawings]

Figures 1 to 5 show an embodiment of the bearing structure of a turret plug in a work boat according to the present invention. Figure 1 is a partial plan view of a thrust bearing, and Figure 2 is a partial plan view of a radial bearing. Partial perspective view, 3rd
The figure is a plan view of the bearing module, FIG. 4 is a sectional view taken along line A-A in FIG. 3, FIG. 5 is a cross-sectional view taken along line B-B in FIG. It is a schematic side view. 1... Hull, 2... Opening, 3... Moon pool, 4... Turret plug, 5... Thrust bearing, 6... Radial bearing, 7... Cable, 8... Bearing module, 9... Bearing Za, 10, 16...Fuchibe, 11...Stopper, 12, 15, 18...
bolt, 13...elastic material, 14...bearing retainer,
17... Holder fitting, 19... Bearing segment.

Claims (1)

[Scope of utility model registration request] The turret plug 4 is rotatably supported by a thrust bearing 5 provided at the top of an opening 2 penetrating the hull 1 of the workboat in the vertical direction and a radial bearing 6 provided inside. A flat bearing seat 9, a bearing retainer 14 placed on the bearing seat 9 via a plate-shaped elastic material 13, and a flat self-supporting member removably supported by the bearing retainer 14. A bearing module 8 is composed of a flat bearing segment 19 having lubricity, and a plurality of thrust bearings 5 are arranged in a ring shape at intervals along the lower surface of the flange portion of the turret plug 4. The radial bearing 6 is a bearing structure of a turret plug in a work boat, in which the radial bearing 6 is arranged circumferentially on the inner surface of the opening 2 at intervals.