GB2101938A - Docking equipment for yachts, motor cruisers and small craft - Google Patents

Abstract

A floating dry dock having a framework of aluminium or steel or other material comprises ballast tanks made of glass-fibre reinforced plastics or other material and ballast valves 14 and 15 in the sides of the tanks. The dock is made in a number of parts which can be bolted together by flanges. Thus the dock may be disassembled into two or more parts for transport. The dock is floated into position and allowed to ground at low tide. The valves are opened to submerge to dock at high tide for accepting boat. The boat settles on the dock at next low tide where the tanks are emptied. Upon next high tide the valves are closed for dock floating. <IMAGE>

Description

SPECIFICATION Docking equipment for yachts, motor cruisers and small craft This invention relates to dry docks and particularly to floating dry docks. An object of the invention is to provide a dry dock of vary simple and inexpensive construction capable of lifting small craft such as yachts, motor cruisers, etc. out of the water. There is a need for such a small dry dock to enable repair and maintenance to be carried out on the hull and underwater surfaces of yachts and pleasure craft, and particularly to enable this to be done in locations where normal docking facilities in harbours or estuaries are not available, or to supplement normal docking facilities.

In accordance with the present invention a method of docking a water-borne craft such as a yacht; motor cruiser, etc., comprises employing a floating dock with buoyancy tanks and ballast valves for allowing water to flow into and out of the tanks, the method comprising: (i) locating the dock in a position where it can lie aground at the next low tide and convenient to the craft to be docked and/or to the repair yard, (ii) when the dock has grounded opening the ballast valves to allow seawater to enter the ballast tanks when the tide returns, (iii) with the dock submerged to a convenient depth floating the craft to be docked over the dock and locating it e.g. by attaching ropes/wires to the corner posts of the submerged dock, (iv) as the tide falls allowing the craft to be docked to settle on the deck of the dock, (v) at low tide allowing the ballast tanks to drain and closing the ballast valves with ballast tanks empty or with a predetermined quantity of ballast retained for stability purposes, (vi) when the tide has risen to a sufficient height allowing the dock to float and lift the craft with it so that the craft is clear of the sealevel and thus the bottom and underwater surfaces can be worked on, For undocking the craft the ballast valves in the dock are opened at low tide thus allowing the dock to remain submerged on the return of the tide. The craftwill float offthe submerged dock as soon asthe tide reaches the floating draft of the craft.

Preferably the structure of the dry dock consists of a framework of steel or aluminium or other material containing a number of buoyancy tanks located in and forming the base of the equipment, the buoyancy of the tanks when filled with air being such as to enable the structure to float and to provide reserve buoyancy sufficient to lift the weight of the craft and to provide adequate safe margin for stability.

Preferably the dock is made in sections which can be assembled and disassembled and transported by lorry or trailer to different locations.

In the accompanying drawings: Figure 1 is a side elevation of a dry dock in accordance with the present invention; Figure 2 is a plan of the dock; Figure 3 is an end elevation of the dock; and Figures 4 to 8 illustrate stages in the docking of a craft.

In Figure 1 is shown a dry dock suitable for use with this invention. The framework of the dry dock is made of aluminium or steel or other material and comprises ballast tanks 12 and 13 made of glassfibre reinforced plastics or other material and ballast valves 14 and 15 in the sides of the tanks supported by and under a simple frame 9.

The dock may be made as shown in a number of parts which can be bolted together by flanges (Figure 3). Thus the dock may be disassembled into two or more parts for transport. There may be four or six or more ballast tanks arranged uniformly about the centreline of the dock.

The dock has stanchions 18, 18a and 19 to which a craft in the dock can be secured. One or more of the stanchions (e.g. 19a in Figure 3) may be adjustable laterally to enable different sizes of craft to be docked.

Remote controls may be provided for the ballast valves. In Figure 1 valve 14 can be operated by turning a turncock 21 which operates through a linkage 22 to open or close the ballast valves 14.

The method of using the dock will now be described with reference to Figures 4 to 8.

In Figure 4 the dock is shown floated out into the sea to a position in which it is desired to dock a craft, the position being chosen such that the dock can lie aground at the next low tide and convenient to a craft to be docked and/or the repair yard.

When the dock has grounded as shown in Figure 5 the ballast valves are opened to allow seawater to enter the ballast tanks when the tide returns. With the dock submerged and resting on the sea bottom the craft to be docked is floated over the dock and located upon it e.g. by attaching ropes/wires 20 to the corner posts 19 of the submerged dock, and as shown in Figure 6, as the tide falls the craft to be docked settles on the deck of the dock.

At low tide the ballast tanks are allowed to drain and the ballast valves are closed with ballast tanks empty or with a predetermined quantity of ballast retained for stability purposes, as shown in Figure 7.

When the tide has risen to a sufficient height the dock will float and lift the craft with it so that the craft is clear of the sealevel and thus the bottom and underwater surfaces can be worked on (see Figure 8).

For undocking the craft the ballast valves in the dock are opened at low tide thus allowing the dock to remain submerged on the return of the tide. The craft will float off the submerged dock as soon as the tide reaches the floating draft of the craft.

One of the advantages of the present invention is that there are no moving parts contained in the equipment other than the valves which control the inlet and outlet of ballast water. No power is required to operate the equipment.

If desired the dock with a craft in it may be towed away to a more convenient location to work on the craft. Several docks may be arranged side by side to form a working area.

This type of dock can be used either where there are no normal docks, harbours, cranes or other equipment, or to supplement existing facilities or in competition with them.

The construction of the dock may be modified in various ways. Bearers may be used to support the hull and keel of a craft and to spread the load and/or lift the hull for access. The bearers may be shaped to accept and support a fin keel. Shoring may be added for additional security.

Claims (8)

1. A floating dry dock comprising a simple framework supported buy a plurality of ballast tanks, the tanks including valves arranged to allow water to enter the tanks from the surrounding water or to drain out of the tanks as required by the user.

2. A dry dock according to claim 1 fabricated in a number of parts which may be easily assembled and disassembled for transport by road.

3. A dry dock according to claim 2 made in two equal parts joined along the central line of the dock.

4. A dock according to any of claims 1 to 3 in which bearers are used to support the hull and keel of a craft when it is in the dock and to spread the load andlorliftthe hull for access.

5. A method of docking a water-borne craft such as a yacht, motor cruiser, etc., comprises employing a floating dock with buoyancy tanks and ballast valves for allowing water to flow into and out of the tanks, the method comprising: (i) locating the dock in a position where it can lie aground at the next low tide and convenient to the craft to be docked andor to the rapairyard, (ii) when the dock has grounded opening the ballast valves to allow seawater to enter the ballast tanks when the ride returns, (iii) with the dock submerged to a convenient depth floating the craft to be docked over the dock and locating it e.g. by attaching ropes/wires to the corner posts of the submerged dock, (iv) as the tide falls allowing the craft to be docked to settle on the deck of the dock, (v) at low tide allowing the ballasttanksto drain and closing the ballast valves with ballast tanks empty or with a predetermined quantity of ballast retained for stability purposes, (vi) when the tide has risen to a sufficient height allowing the dock to float and lift the craft with it so that the craft is clear of the sea level and thus the bottom and underwater surfaces can be worked on.

6. A floating dry dock consisting of a framework of steel or aluminium or other suitable material, containing a number of buoyancy tanks located in and forming the base of the dock, the buoyancy of the tanks when filled with air being such as to enable the structure to float and to provide reserve buoyancy sufficient to lift the weight of a craft located in the dry dock and to provide adequate safe margin for stability.

7. A floating dry dock substantially as hereinbefore particularly described and as illustrated in the accompanying drawings.

8. A method of docking a water-borne craft substantially as hereinbefore particularly described and as illustrated in the accompanying drawings.