EP1448435A1

EP1448435A1 - Dry dock and module for such a dry dock

Info

Publication number: EP1448435A1
Application number: EP02743957A
Authority: EP
Inventors: Dirk Borsboom
Original assignee: Boat Drydock Systems
Current assignee: Boat Drydock Systems
Priority date: 2001-06-22
Filing date: 2002-06-10
Publication date: 2004-08-25
Also published as: WO2003000545A1; NL1018365C1

Abstract

The invention relates to a dry dock, provided with a floating body and support means (20a, 20b, 20c, 20d, 21a, 21b, 21c, 21d), mounted onto it for supporting a boat, where the floating body is built up of modules (1). The modules (1) are provided with coupling means, suitable for coupling the modules in a floating situation together to a floating body. Once all the modules (1) have been coupled, profiles (15,16) can be mounted in a longitudinal and a transverse direction of the floating body, onto which the support means (20a, 20b, 20c, 20d, 21a, 21b, 21c, 21d) can be mounted.

Description

Dry dock and module for such a dry dock

The invention relates to a dry dock, provided with a floating body and support means, mounted on the floating body, for supporting a boat. Dry docks of this type are used in the professional shipping trade, but also increasingly in the pleasure cruising sector. A dry dock built for the pleasure cruising sector is for example known from EP-A-0 768 235. This known dry dock is suited for relatively small boats, but weighs in spite of that many tons. Its large weight and also its large dimensions limit the field of application, because small harbours are often not accessible for heavy traffic of this kind and because there are no local hoisting facilities and they cannot be brought in either.

The present invention is based on the observation that the weight and the volume of the dry dock is determined substantially by the floating body. The inventive dry dock is therefore, according to an aspect of the invention, characterized in that the floating body is built together from modules. This implies that the dry dock can be transported in the form of a number of relatively light modules, which can easily be handled and be put together at the spot.

A favourable embodiment of the inventive dry dock is characterized in that the modules are provided with first coupling means, designed for coupling the modules in a floating situation together for obtaining a floating body. Because the floating body can be put together now while positioned in the water, a small, locally available hoisting facility is sufficient for launching the dry dock. A further favourable embodiment is characterized in that the modules are provided with second coupling means, for coupling to longitudinal beams, extending in a longitudinal direction of the dry dock, and to cross beams, extending in a cross direction of the dry dock. In this way, a surface consisting of alternating modules and cross beams is realised, of which the modules provide the floating power and the cross beams are capable of carrying a load.

A further favourable embodiment of the inventive dry dock is characterized in that the support means are mounted movable on the longitudinal beams and on the cross beams. Preferably, the usually four pillars that support a boat are mounted onto the longitudinal beams, such that a shift into a longitudinal direction can easily be realised. A set of four hydraulically steered posts which are used for hoisting up the hoisting belts which run underneath the boat are preferably mounted onto the cross beams, such that a shift into a transverse direction can easily be realised.

A favourable embodiment according to a further aspect of the invention is characterized in that at least part of the modules is connected to a compressed air control system for making the dry dock go up or go down in a controlled manner. Preferably, the compressed air control system is implemented in such a manner that for each module the air inlet opening and the air outlet opening contains the same type of restriction, such that for each module the same amount of air is let in or from each module the same amount of air is let out. This results in a modular dry dock which is very stable.

A favourable embodiment according to a further aspect of the invention is characterized in that of at least some of the modules a bottom side is sealed with a membrane made of a synthetic material. This synthetic membrane prevents the inside of the modules from becoming dirty during use, such that the floating power and the stability of the dry dock will remain the same even after a prolonged period of use.

A favourable embodiment according to a further aspect of the invention is characterized in that landing stages are provided, positioned alongside the dry dock, and stabilisation means, positioned between the dry dock and the landing stages, for stabilising an upward or downward movement of the dry dock. A favourable realisation of this embodiment is characterized in that the stabilisation means comprise a system of slide bearings with cylinders coupled to it and that the cylinders are mutually coupled with tubes or pipes. In this manner, a reliable system is realised for which only a limited number of mechanical parts must be positioned underneath the water surface.

The invention also relates to a module, suitable to be used in a dry dock as disclosed.

A favourable embodiment of the inventive module is characterized in that the module comprises a profiled frame made of steel or a synthetic material, provided with a connection for compressed air, on a top side sealed with a floor board, impermeable to gas, on a bottom side sealed with a membrane made of a synthetic material and on the sides provided with coupling means for coupling to other modules. A module constructed in this manner is affordable and demands little maintenance. Also the weight can be kept within limits. A module of this type of 2 x 2 meters weighs typically 500 kilos and has a lifting power of 1500 kilos.

The invention will now be further explained with a reference to the following figures, in which: Fig. 1A represents in top view a possible embodiment of a module; Fig. IB represents this module in cross section; Fig. 1C represents in cross section more in detail how the coupling between two modules takes place;

Fig. 2 represents in top view a possible embodiment of a dry dock, built together from these modules; Fig. 3 represents this dry dock in front view; Fig. 4 represents this dry dock in side view; Fig. 5 schematically represents a system of legs between which the dry dock can move.

Fig. 1A represents in top view a possible embodiment of a module 1, consisting of a profiled frame 2 of for example stainless steel or a synthetic material, on a top side closed by a panel 3 which forms an airtight cover for the module and which is moreover fit to walk on, for example made of recycled polyethylene. The sides of frame 2 are provided with brackets 4, with which modules 1 can be coupled. The bottom side of module 1 is sealed with a membrane made of a synthetic material, not visible in this figure, in such a manner that module 1 can be filled with air, via an air inlet 5, for regulating the floating power of module 1. Onto the coupled modules, a system of profiles can be fixed onto which supports can be mounted. For fixing the profiles, frame 2 is provided with clamping blocks 6, between which a bolt can be pushed.

Fig. IB represents this module 1 in cross section, with profiled frame 2, onto which panel 3 is screwed and glued, such that an airtight joint is obtained. On the bottom side, the periphery of profiled frame 2 is provided with a flange 7, onto which a plastic membrane 9 is clamped with the aid of a metal frame 8. On frame 2, an air inlet 5 is mounted via which compressed air can be supplied for regulating the floating power of module 1. On the left side of the figure, membrane 9 is shown in an inflated situation and on the right side of the figure in a practically deflated situation. For coupling the modules, the sides of frame 2 are provided with brackets 4 and for fixing the profiles 10, the sides of frame 2 are provided with clamping blocks 6.

Fig. 1C represents in cross section more in detail how the coupling between two modules takes place. In a vertical cross section, brackets 4a, 4b are L-shaped, in such a way that for brackets 4a the short leg points upwards and for brackets 4b the short leg points downwards. It is possible then to install on and underneath brackets 4a, 4b two clamping plates 11a, lib and to fix these with the aid of a bolt and nut 12. Between adjacent modules the I-shaped profiles 10 can be placed and fixed with the aid of bolts and nuts 13, which have been shifted between clamping blocks 6, connected to frame 2 and with which clamping plates 14 are fixed. By rotating the clamping plates in a position shown here and by subsequently tightening bolts and nuts 13, the modules are clamped onto the surrounding I-shaped profiles 10, in such a manner that together they form a rigid surface, suitable for carrying for example a boat.

Fig. 2 represents in top view a possible embodiment of a dry dock built together from these modules 1, between which in a longitudinal direction I-shaped profiles 15 are fixed and in a transverse direction I-shaped profiles 16 are fixed, each of them being mounted to the frames 2 of the different modules with the aid of clamping plates 14. One may now make the entire dry dock sink by letting air out of the modules and make the entire dry dock float by blowing air into the modules, even when a boat is placed onto the dry dock. In order to raise the boat in a controlled manner, the dry dock is provided with two hoisting belts 17,18, connected to hydraulically steered posts, by which the boat is temporarily carried while being lifted off the water by the raising dry dock. The hydraulically steered posts are mounted on four I-shaped profiles 16 and may slide in a transverse direction.

In order to prevent the dry dock from drifting away, landing stages 19a, 19b, 19c are provided which are fixed onto or into the bottom. If desired, landing stage 19b can be left away which has as an advantage that a boat may sail through the dry dock. Alongside landing stages 19a and 19c about eight legs are placed, between which the dry dock may slide upwards or downwards. With the aid of these legs and with a system of cables, cylinders and tubes connected to it, it is prevented that the dry dock becomes unbalanced and in an extreme situation even capsizes.

Before the dry dock is put together, at least one of the landing stage parts 19a, 19b, 19c is placed near the shore in order to serve as a working platform. The mounting of the dry dock consists of the successive mutual connection of the floating modules with the aid of the clamping plates 11a, lib, as shown in Fig. IC, until the entire surface is connected. Then, the I-shaped profiles 15,16 are screwed in place. Next, the floating surface thus obtained can be used for mounting the remaining landing stage parts and legs.

Fig. 3 represents the dry dock in front view, with landing stage parts 19a and 19c, I-shaped profiles 15,16 and modules 1. On profiles 16, four hydraulically steered posts 20a, 20b, 20c, 20d are placed, between which the boat is positioned with the aid of the hoisting belts 17,18 which temporarily carry the boat. With the aid of the hydraulically steering one can place the boat onto the pillars 21a, 21b, 21c, 21d. For controlling the compressed air control system and the hydraulically steered posts 20a, 20b, 20c, 20d, a console 22 is placed for example on landing stage part 19b.

Alongside landing stages 19a and 19c, the legs are visible along which the dry dock can slide upwards or downwards. With the aid of these legs and with a system of cables, cylinders and tubes connected to it, it is prevented that the dry dock becomes unbalanced and in an extreme situation even capsizes.

Fig. 4 represents the dry dock in side view, with landing stage 19c, modules 1, hydraulically steered posts 20a, 20b, pillars 21a, 21b and the legs along which the dry dock can slide upwards or downwards.

Fig. 5 schematically represents a system of legs 23a, 23b, .. , 23h, between which the dry dock can slide up and down. On a top side, the legs are connected to the landing stage parts 19a, 19b, 19c, here symbolically represented by a dotted line. The surface 24, formed by the modules 1 and the I-shaped profiles 15,16 is connected to slide bearings 25a, 25b, .. , 25h which can slide over the legs 23a, 23b,.., 23h. Slide bearings 25a, 25b, .. , 25h are connected by cables to cable cylinders 26a, 26b,.., 26h, in which pistons are situated. Of the cable cylinders 26a, 26b, .. , 26h, always a top side is connected to a bottom side of another cylinder, as a result of which the movements of the pistons become mutually coupled and the dry dock can only move upwards or downwards in a vertical direction. The cable cylinders as such are known in the art and are operationally filled with a non-compressable liquid, for example a mixture of water and glycol.

Claims

1. Dry dock, provided with a floating body and support means, mounted on the floating body, for supporting a boat, characterized in that the floating body is built together from modules .

2. Dry dock according to claim 1, characterized in that the modules are provided with first coupling means, designed for coupling the modules in a floating situation together for obtaining a floating body.

3. Dry dock according to claim 2, characterized in that the modules are provided with second coupling means, for coupling to longitudinal beams, extending in a longitudinal direction of the dry dock, and to cross beams, extending in a cross direction of the dry dock.

4. Dry dock according to claim 3, characterized in that the support means are mounted movable on the longitudinal beams and on the cross beams.

5. Dry dock according to one of the previous claims, characterized in that at least part of the modules is connected to a compressed air control system for making the dry dock go up or go down in a controlled manner.

6. Dry dock according to one of the previous claims, characterized in that of at least some of the modules a bottom side is sealed with a membrane made of a synthetic material .

7. Dry dock according to one of the previous claims, characterized in that landing stages are provided, positioned alongside the dry dock, and stabilisation means, positioned between the dry dock and the landing stages, for stabilising an upward or downward movement of the dry dock.

8. Dry dock according to claim 7, characterized in that the stabilisation means comprise a system of slide bearings with cylinders coupled to it and that the cylinders are mutually coupled with tubes or pipes.

9. Module, suitable to be used in a dry dock according to one of the previous claims.

10. Module according to claim 9, characterized in that the module comprises a profiled frame made of steel or a synthetic material, provided with a connection for compressed air, on a top side sealed with a floor board, impermeable to gas, on a bottom side sealed with a membrane made of a synthetic material and on the sides provided with coupling means for coupling to other modules.