US3497888A - Buoys - Google Patents

Description

March 3,'197o J. w; R058 Em ,497,8

I BUOYS Original Filed Nov. 22. 1965 4 Sheets-Sheet 1 March 3, 1970 J. w. R055 ETAL 3,497,888

BuoYs v Original med Nov. 22. 1965 4 Sheets-Sheet 2 INVENTORS, JOHN WILLIAM ROSS KENNETH WILLIAM norms BY MO RGAN, FINNEGAN, DURHAM a PINE r ATTORNEYS.

March 3, 19 70 J. w. R055 ET L 3,497,883

BUOYS Original Filed-Nov. 22. 1965 4 Sheets-Sheet 5 INVENTORS, J OHN WILLIAM ROSS KENNETH WILLIAM HOPKINS;

MORGAN, FINNEGAN, DURHAM a PINE ATTORNEYS March 3, 1970 J, w. 5 ErAL 3,487,888

. wows 8 Original Filed Nov. 22. 1965 N 4 Sheets-Sheet 4 INVENTORS, JOHN WILLIAM R088 KENNETH WILLIAM HOPKINS BY MORGAN F'INNEGAN, DURHAM & PINE ATTORNEYS United States Patent 3,497,888 BUOYS John William Ross, New Malden, and Kenneth William Hopkins, Long Ditton, England, assignors to BP Tanker Company Limited, London, England, a British jointstock corporation Continuation of application Ser. No. 514,748, Nov. 22, 1965, which is a continuation of application Ser. No. 353,332, Mar. 20, 1964. This application Oct. 11, 1968 Ser. No. 768,215

Int. Cl. B63b 21/52 US. Cl. 9-8 6 Claims ABSTRACT OF THE DISCLOSURE A terminal for the mooring of sea-going vessels in which at least a major portion of the buoyancy chamber is continuously submerged. The mooring cables are continuous, passing from the buoyancy chamber to a single point mooring member anchored at the sea bed, and are of a length so as to moor the buoyancy chamber in the submerged position, so that tension is continuously maintained on the mooring cables.

This application is a continuation of application No. 514,748, filed Nov. 22, 1965, which was a continuation of application No. 353,332 filed Mar. 20, 1964; both of which are now abandoned.

This invention relates to buoys and particularly to buoys suitable for use in so-called single point mooring of ships, especially tank ships.

In single point mooring arrangements, a ship is usually moored by a cable from the bow of the ship to a buoy, the ship being capable of rotating 360 around the buoy. Buoys used for single point mooring are extremely large, i.e. up to feet in diameter, and have to withstand extreme stresses and strains to hold a ship in position. Hence extremely large cables or chains have to be used to moor the buoy to the sea bed, these cables being prone to wear due to constant movement of the buoy with the sea.

At the present time, if the cables are required to be replaced or inspected for maintenance purposes, the exercise is an arduous and expensive one involving the use of divers.

It is accordingly an object of the present invention to alleviate the above-mentioned difiiculties.

According to one aspect of the present invention, we provide a mooring arrangement comprising a mooring member anchored at or near the sea bed, and a buoy moored to it by at least one continuous cable passing from the buoy down to the mooring member and up again to the buoy in such manner that a replacement cable can be attached to one end of said cable at the buoy and by pulling the other end of the said cable the replacement cable can be brought into position for mooring the buoy.

The mooring member may be anchored at or near the sea bed by a plurality of further cables preferably fixed to the member at equidistantly spaced intervals around its periphery.

According to a further aspect of the invention, we provide a buoy comprising a buoyancy chamber having a plurality of ducts facilitating access for mooring cables to mooring means located at one end and external of the chamber, the arrangement being such that, in use, mooring cables pass from the sea bed up through the ducts in the buoyancy chamber, which is kept almost completely submerged, to the mooring means above sea level, whereby the mooring cables are maintained under tension to reduce wear.

3,497,888 Patented Mar. 3, 1970 Preferably the mooring means is contained in a hollow chamber, and is arranged such that, in use, the cables are fixed to it so as to be equidistant from and equidistantly spaced around the vertical centre line of the buoy whereby, the cables tend to maintain the buoy in a vertical position in the sea.

The buoy may be provided with a combined rotatable mooring hook and piping arrangement whereby a tank ship can be moored to the buoy to load and unload liquid cargo.

According to a still further aspect of the invention, We provide a mooring member adapted, in use, to be anchored at or near the sea bed and formed with at least one arcuate duct arranged so that, in use, at least one cable having its ends fixed to a buoy passes through the duct thereby mooring the buoy to the sea bed.

Preferably the mooring member has a plurality of lugs spaced equidistantly around its periphery whereby, in use, a cable can be attached to each lug, each cable being anchored to the sea bed so anchoring the member at or near the sea bed.

In order that the invention can be more clearly understood a specific embodiment thereof will heerinafter be described, by way of example only, with reference to the accompanying drawings, in which FIG. 1 shows a buoy moored via a mooring member to the sea bed;

b FIG. 2 shows a front elevation, part cut away, of a FIG. 3 shows a side elevation of the buoy of FIG. 2;

FIG. 4 shows a front elevation of the buoy of FIGS. 2 and 3 looking from the opposite side of the buoy to FIG. 2;

b FIG. 5 shows an elevational view of a mooring mem- Referring fir'stly to FIG. 1 there is shown a buoy 11 moored by two continuous cables, which pass through a mooring member 13, two ends 12a and 12b of one cable and one end 12c of the other cable being shown. The mooring member 13 is anchored to the sea bed 14 by cables 15 fixed at their other ends to fixtures 16 in the sea bed 14.

The cables 12 are of such a length as to maintain the buoy 11 almost submerged against its buoyancy, so maintaining the cables 12 under tension. The tensioning of cables 12 reduces wear of the cables, by reducing the possibility of sudden stresses being applied to them when the buoy ils buffeted in bad weather.

A fender (not shown) is provided around the buoy 11 near its top, so that the buoy is safeguarded against damage by a ship striking it in bad weather.

Referring now to FIGS. 2, 3 and 4, the buoy 11 of FIG. 1 is shown on an enlarged scale and in greater detail. The buoy comprises a cylindrical buoyancy chamber 17 formed with ducts 18 (FIG. 2) to allow the cable ends 12a, 12b and to pass from mooring lugs 19, to which they are shackled down to the mooring member 13 On the sea bed.

The mooring lugs 19 are positioned equidistantly around a centrally disposed pipe member 20 to maintain the buoy in an upright position, and are enclosed by a conical member 21 (shown part cut away in FIG. 2). The conical member 21 is provided with manholes (not shown) to allow access to the cables 12.

The pipe member 20 extends vertically for the com plete length of the buoy (only part shown) and is connected to flexible piping (not shown) which passes along the sea bed to the mainland.

A manifold arrangement 22 is rotatably mounted at the top of pipe member 20. The manifold arrangement 22 is of the type disclosed in our copending United States patent application Ser. No. 387,748 and therefore will not.

be described herein.

A combined mooring and piping arrangement 23 is carried by a bush 24 which is rotatably mounted on the pipe member 20 below the manifold arrangement 22.

The piping arrangement comprises a valve 25, carried by a member 26, connected at one side to the manifold arrangement 22 and at the other side to a Y shaped piping which can be connected by flexible piping 27 to a tank ship (not shown).

The mooring arrangement comprises an inverted Y shaped member 28 having its arms rotatably mounted on the bush 24, to allow movement as shown in dotted lines in FIG. 3, and its leg formedas'a ring to which a ship can be moored. Thus the ship mooring member 28, being rotatable in a vertical plane, follows the up and down motion of a moored ship as it moves with the tide and, being also mounted on pipe member 20' by means of bush ,24 for rotation about its longitudinal axis, permits the ship to rotate 360 around the buoy.

Referring finally to FIG. the mooring member 13 (FIG. 1) is shown on larger scale and in greater detail. The member 13 is formed with a number of lugs 29 to accommodate cables for mooring it at or near the sea bed, and is formed with two ducts 30 through which the cables from the buoy pass.

What is claimed is:

1. A single point mooring arrangement adapted to provide a terminal for the mooring of sea-going vessels comprising: a single point mooring member fixedly anchored at the sea bed; a mooring buoy, said moring buoy including a single, unitary buoyancy chamber carrying both ship mooring means and buoy mooring means, said buoyancy chamber having at least a major portion thereof continuously submerged, said buoyancy chamber further having a plurality of ducts therein and said buoy mooring means is located at one end and external of said buoyancy chamber and said ducts terminate at said buoy mooring means; and a plurality of mooring cables passing directly from said mooring member through said ducts in said buoyancy chamber to said buoy mooring means, said mooring cables being of a length so as to moor said buoyancy chamber in said submerged position, the buoyancy of said buoyancy chamber thereby continuously maintaining tension on said mooring cables.

2. A mooring arrangement as claimed in claim 1, wherein said buoy mooring means is contained in a hollow chamber, and wherein said mooring cables are fixed to said buoy mooring means so as to be equidistant from and equidistantly spaced around the vertical center line of said buoy to thereby maintain said buoy in a substantially vertical floating position. 1

3. A single point mooring arrangement adapted to provide a terminal for the mooring of sea-going vessel comprising: a single point mooring member anchored at the sea bed; a mooring buoy, said mooring buoy including a buoyancy chamber carrying ship mooring means and buoy mooring means; said buoyancy chamber including a plurality of ducts therein and, said buoy. mooring means being located at one end and external of said buoyancy chamber, said ducts terminating at said buoy mooring means; a plurality of continuous mooring cables passing through said ducts in said buoyancy chamber from said buoy mooring means to said mooring member and back to said buoy mooring means; said mooring member including means permitting said cables to be passed therethrough, whereby a replacement cable attached to one end of a mooring cable at said buoy may be pulled through said mooring member so as to replace the mooring cable.

4. A mooring arrangement as claimed in claim 3, wherein said buoy mooring means is contained in a hollow chamber, and wherein said mooring cables are fixed to said buoy mooring means so as to be equidistant from and equidistantly spaced around the vertical line of said buoy to thereby maintain said buoy in a substantially vertical floating position.

5. A single point mooring arrangement adapted to provide a terminal for the mooring of sea-going vessels comprising: a single point mooring member anchored at the sea bed; a mooring buoy, said mooring buoy including a buoyancy chamber carrying ship mooring means and buoy mooring means, said buoyancy chamber having at least a major portion thereof continuously submerged; said buoyancy chamber including a plurality of ducts therein and said buoy mooring means being located at one end and external of said buoyancy chamber, said ducts terminating at said buoy mooring means; and plurality of continuous mooring cables passing through said ducts in said buoyancy chamber from said buoy mooring means to said mooring member and back to said buoy mooring means, said mooring cables being of a length so as to moor said buoyancy chamber in said submerged position, thereby continuously maintaining tension on said mooring cables; said mooring member including means permtting said cables to be passed therethrough, whereby a replacement cable attached to one end of a mooring cable at said buoy may be pulled through said mooring member means so as to replace the mooring cable.

-6. A mooring arrangement as claimed in claim 5, wherein said buoy mooring means is contained in a hollow chamber, and wherein the mooring cablesare fixed to said buoy mooring means so as to be equidistant from and equidistantly spaced around the vertical center line of said buoy to thereby maintain said buoy in a substantially vertical floating position.

References Cited UNITED STATES PATENTS TRYGVE M. BLIX, Primary Examiner

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