GB2399791A

GB2399791A - Internal hydraulic jacking system for self dry docking of vessels

Info

Publication number: GB2399791A
Application number: GB0409060A
Authority: GB
Inventors: Hewie Edward Dalrymple; Edward Alexander Scott
Original assignee: Individual
Current assignee: Individual
Priority date: 2004-04-23
Filing date: 2004-04-23
Publication date: 2004-09-29
Anticipated expiration: 2024-04-23
Also published as: GB2399791B; GB0409060D0

Abstract

A vessel is provided with an internal hydraulic jacking system that allows the vessel to lift itself up on a suitable surface to 'dry-dock' itself The jacking system comprises a number of pairs of hydraulic jacks, arranged at intervals along the length of the vessel (Fig 3), at specially strengthened locations. Each hydraulic jack comprises an extendable hydraulic ram 3 with a pivoted foot 5 at its lower end, which can be fully retracted within a recess 4 and 6 in the hull 1 when not in use.

Description

239979 1 At.

DESCRIPTION.

There is no internal system in the world to date that allows any vessel to actually "Dry Dock" herself.

This system as a new invention herewith is designed for any strong alloy or GRP (Glass reinforced plastic) vessels that have hydraulics on board.

Problem 1. A particular problem that this system solves is where vessels over 250 feet long have to sit on blocks of wood in dry docks. As the vessel sits on the blocks to be antifouled the antifouling paint never gets to the areas directly on top of the block because the vessel is sitting on the block that is underneath. Every time the vessel comes into the dry dock exactly the same problem occurs, therefore the vessel never receives paint to this area. If any vessel had this system aboard this problem would then be eliminated.

Problem 2. The problems in being able to lift an entire vessel of the ground or off a bogie on a slipway to be able to work on the 'face' of the keel is a surmountable task, fraught with numerous dangerous problems to those people involved and the cost is always very expensive, whereas if any vessel had the appropriate hydraulic jacks in a vessel, this system then eliminates the problem.

Problem 3. Some small fishing boats, private motor cruisers and yachts have to be rolled over onto their sides to gain access to the lower hull. In doing so damage is often caused to the side of the hull that is on the ground. Rolling a vessel often does more internal damage to the ribs and stress points of the vessel whereas if these smaller vessels had the appropriate placed hydraulic jacks within the hull these problems and perils would be minimised.

Problem 4. When yachts go world cruising they often have numerous problems with not being able to get at the hull areas underneath the water line. If any yacht had sufficient jacks to allow the vessel to sit up right on any beach, this system would eliminate this problem.

Problem S. Many vessels have 'legs' that allow the vessel to sit up right on her keel and the then legs are bolted through the hull to a capping plate on the inside of the hull. These legs have a bad habit of snapping and then the vessel falls over onto the broken leg, this then often causes severe damage to the vessels hull and ribs.

If this system were installed it would eliminate this problem.

Problem 6. It would be considerable easier and cheaper to replace the steel foot on the bottom of any hydraulic ram foot than it would be to take the respective areas of rusty steel from the bottom of any large vessel that at present has to sit on dry dock blocks.

2 hydraulic rams are attached to any watertight alloy or GRP bulkhead or suitable position within the vessels hull at distances that give an even lift without straining the vessels construction and keel.

Regarding to where the extra weights are in any given vessel a suitable hydraulic ram of representative tonnage would be sited next to that area.

If there is nowhere for a vessel to moor up or because it is too expensive to moor up or if the master of a vessel wishes to undertake an inspection of any part of the lower hull or the underneath of the keel of the vessel (the face) or to do any work on the hull at all, this system allows it to be done in safety between tides or on any suitable hard standing ground or slipway.

Should any vessel require to be transported by a low loader road trailer, the vessel could jack herself up on her hydraulic rams to allow the driver to back the road trailer underneath the vessel to pick her up. This would then save having to get a telescopic crane in to lift the vessel.

With having extra hydraulic rams in any vessel, this then allows any vessel to have less concrete or lead or pig iron as ballast therefore more flooring space is freed up by having less ballast m the bottom of the vessel. The low positioning of the rams within the hull of any vessel does not detract from any vessels stability and the weight of the hydraulic rams counterbalance each other.

EXPLANATION OF DRAWINGS NUMBERS.

No 1 is the hull.

No 2 is the keel or foot f the vessel.

No 3 is the hydraulic ram extended.

No 4 is the hydraulic ram housing.

No 5 is the pivoted foot that fits on the bottom of the extended hydraulic ram allowing the vessel to be lifted up.

No 6 is the recess the hydraulic foot fits into and makes a flush fitting with the exterior of the hull when the vessel is afloat.

No 7 is a water tight bulk head.

No 8 is the deck of the vessel.

No 9 is the top stringer. This is a piece of metal for a steel vessel or wood for a wooden vessel or strengthened GRP (Glass reinforced Plastic) for a fibreglass boat, vessel or ship.

No 10 is the second stringer that would be required if any vessel had this self dry docking system installed. The reason for the second stringer is to give round-bilged vessels more adequate strength to the existing hull. 3.

EXPLANATION OF THE DRAWINGS.

Figure I shows a section of a chined vessel (Round bilged) with a keel and 2 hydraulic rams extended.

Figure 2 shows the starboard (Right hand side) side view of a vessel without the hull casing, allowing you to see the differences between the widths of the hydraulic ram housings according to the weights of the contents in the vessel.

Each vessel will require a different strengthed hydraulic ram to be at certain positions of the vessel and attached to the individual watertight bulkheads No 7 but all hydraulic rams must have the same length of ram when fully extended.

Figure 2 also shows the positioning of the feet of the hydraulic rams No 5 when recessed into the vessel.

Figure 3 shows the viewer the diagram of the bottom of the hull as viewed from beneath with respective positioning of the hydraulic ram feet No 5 are recessed into the hull No 1 of the vessel.

CLAIM

An internal hydraulic jacking system that allows any vessel to Dry Dock herself by lifting the vessel up off the ground in an upright position.

Claims

Amendments to the claims have been filed as follows: S 1. A vessel having

an internal hydraulic jacking system that allows the vessel to lift itself up on a suitable surface in an upright position to 'dry-dock' itself and allow maintenance to be carried out on a keel face of the vessel, wherein the system incorporates at least two pairs of hydraulic jacking legs, the pairs of legs spaced in tandem fashion along the length of the vessels hull, so as not to cause stress to the hull of the vessel when raised on its legs.
2 A vessel as claimed in claim 1 wherein each pairs of legs is positioned at a specie cally strengthened location on the hull of the vessel or at a location of an internal bulkhead of the vessel.