GB2264269A

GB2264269A - Diving installation

Info

Publication number: GB2264269A
Application number: GB9203841A
Authority: GB
Inventors: Thomas Olaf Riiser
Original assignee: Stolt Nielsen Seaway AS
Current assignee: Stolt Nielsen Seaway AS
Priority date: 1991-02-07
Filing date: 1992-02-22
Publication date: 1993-08-25
Anticipated expiration: 2012-02-22
Also published as: NO910482L; GB9203841D0; NO172036B; NO910482D0; GB2264269B; NO172036C

Abstract

A diving installation comprising a carrier ship or other equipment carrier above the sea surface, a diving bell (18), a movable carrying apparatus (11, 12) for said diving bell on said equipment carrier, equipment (17, 19, 20, 22, 24) for raising/ submerging said diving bell between a diving position and a coupling position on the equipment carrier, and a diving chamber assembly (25, 27) on the equipment carrier, and means (10, 13) for moving said movable carrying apparatus with said diving bell attached to and from a coupling position with the diving chamber assembly, characterized by means (10, 13) for guiding said carrying apparatus (11, 12) in a horizontal circuit, and in that the diving chamber assembly comprises a plurality of diving chambers (25) lined up in a corresponding horizontal circuit. <IMAGE>

Description

The invention relates to a diving installation comprising a carrier ship or other equipment carrier above the sea surface, a diving bell, a movable carrying apparatus for the diving bell on the equipment carrier, equipment for raising/submerging the diving bell between a diving position and a coupling position on the equipment carrier, a diving chamber assembly on the equipment carrier, as well as means for moving the movable carrying apparatus with diving bell attached to and from a coupling position with the diving chamber assembly.

The terms carrier ship or other equipment carrier above the sea surface are to be understood here as ships and floats from which there is a need to be able to execute diving operations, and also fixed installations in the sea from where it is necessary to execute diving operations. The term diving bell is to be understood here as a body which can be submerged in the sea, carrying one or more divers who would be able to operate in the diving bell or outside it. The diving bell may have its own means of propulsion. The term diving chamber should be understood in this context as a pressurized chamber which can be coupled to the diving bell and which serves as compression chamber, accommmodation and decompression chamber for personnel. A diving chamber may also be used as a pure accommodation chamber, so-called living quarters.

To have a diving chamber on board the equipment carrier during diving work is known. The divers can enter the chamber and be subjected to compression, whereupon they transfer to a coupled diving bell which then takes them down to the depths of the ocean. Whilst the diving bell is in operation, a new diving team can, for example, enter the diving chamber and be prepared (subjected to compression) for diving, so that the new diving team can replace the first team when it comes up and goes into the diving chamber once more. The first diving team can then be subjected to decompression and, after this is terminated, it may leave the diving chamber.The first diving team may also, of course, stay in the diving chamber under diving pressure and thus spend a rest period in the diving chamber, whereafter it can change places with the team that has been at work, and so on, or optionally go into a new diving bell which is coupled to the diving chamber.

The purpose of the invention is to provide a diving installation of the kind described by way of introduction which will be capable of providing great ecomony of space used - on board an equipment carrier there will, as a rule, be limited space - and a rational solution with regard to operation (food, equipment) as well as great flexibility, especially with regard to the possiblities of being able to carry out dives at many depths (pressures), with a high coefficient of utilization of the diving system.

According to the invention, a diving installation is therefore provided as described in the introduction, characterized by means for guiding a carrying apparatus in a horizontal circuit, and in that the diving chamber assembly comprises a plurality of diving chambers lined up in a corresponding horizontal circuit.

This solution means that the diving bell by means of said carrying apparatus can reach any one of said diving chambers in a rapid and efficient way, great savings are made with regard to space used as a result of the positioning of the diving chambers and a rational solution can also be attained in respect of operation (food, equipment), as well as a correct positioning of the necessary control centre in the middle of the circuit.

Great flexibility may be attained by choosing the number of chambers to correspond to a number of depths (pressures). This provides a high coefficient of utilization of the diving installation accompanied by increased efficiency.

A particularly advantageous solution according to the invention is where the means for guiding the carrying apparatus comprises a rotatory support and a carrying arm mounted thereon for guiding the carrying apparatus in a circular circuit. With the diving chambers arranged in a circle, the handling system will be extremely efficient and can easily be automated.

According to the invention, advantageous means for guiding the carrying apparatus may comprise a circular rail for supporting the carrying arm coaxial with the rotatory support. With a solution of this kind, the carrying arm will be rotationally supported centrally in the rotatory support and be supported from below by the circular. This provides simple and secure support and guiding of the carrying apparatus.

Particularly advantageous according to the invention is the fact that the diving chambers can be arranged at a horizontal level below the coupling position of the diving bell, in the horizontal circuit of the diving bell, i.e. the diving bell by means of the carrying apparatus can be brought to a coupling position above a respective diving chamber, with corresponding economy of space in the horizontal plane.

Especially advantageous, in particular in this connection, is the fact that each diving chamber may have an upper wet compartment and a lower accommodation compartment. The wet compartment is the compartment or room in the diving chamber which contains a toilet, shower and changing room, and it is advantageous to use this compartment as the exit/entrance room, because a high living standard can thereby be attained in the lower accommodation compartment with a minimum of disturbance in the chamber. This is of particular significance when the work takes place at a great depth which makes extra demands on the divers.

A particularly rational and space-saving embodiment is one wherein the equipment for raising/submerging the diving bell is placed on and supported by the movable carrying apparatus for the diving bell.

Raising and submerging the diving bell can take place in the open, e.g. along the side of a ship, but usually one chooses to have a shaft (moonpool) in the equipment carrier for raising and submerging the diving bell. This involves many advantages which are well known to a person skilled in the art. In an especially advantageous way, a shaft of this kind can be positioned in the horizontal circuit of the diving bell. In a raised position the diving bell will then be in its coupling position and can thus be quickly and simply put in the coupling position relative to the diving chambers, with a minimum of handling.

In particular when the diving chambers are arranged at said level below the level of the coupling position of the diving bell, but also in other instances, the diving chambers can advantageously be supported and fixed at the mean height of the equipment carrier, above the level of the diving machinery.

On board a carrier ship in particular a mounting of this kind, at the mean height will be of significance as a reduced level of noise penetration is attained. Placing the diving chambers with the diving machinery room below gives rise to minimal construction and connecting costs.

Of particular advantage and independent inventive merit is an embodiment of the diving installation with a second diving bell having a corresponding second movable carrying apparatus, as well as means for guiding said second carrying apparatus in the same horizontal circuit as the first, to and from a coupling position with said diving chamber assembly. The use of two diving bells (one could also consider a greater number) provides increased flexiblity with a high coefficient of utilization of the entire installation, and increased safety in particular is attained for the divers. If an accident should happen in the submerged diving bell, a new bell could be sent down rapidly, with or without a rescue team. A diving bell can thus be "at work" whilst the other is on standby or also in operation.

In addition to the advantages already mentioned, each diving chamber needs to be designed for one diving team only, which means that the living environment will be considerably improved. A greater number of chambers, for instance eight, results in a diving team being able to live in the same chamber throughout their stay on board, from compression through their working period and into decompression. This simplifies the whole diving system radically and provides the divers with a much more secure stay on board. The new diving installation could be controlled in a much safer way either by today's manual methods or by automating the system, because each diving chamber caters for one diving team only. The invention allows the diving chambers to be reached by a diving bell in a rapid and efficient manner.The diving chambers do not need any sluices which link the individual chambers together. This leads to considerable saving in terms of both construction and installation.

The invention shall now be described in more detail with reference to the drawing where: Figure 1 shows a schematic outline of a diving installation according to the invention.

Figure 2 shows a schematic vertical section through the diving installation shown in figure 1.

The diving installation in the embodiment example is designed to be placed on board a carrier ship, the port side of which is indicated with the numeral 1, and the starboard side of which is indicated with the numeral 2. The double bottom of the ship is labelled 3, the main deck of the ship is marked 4, an upper deck 5 and a between deck 6.

The ship has a port shaft 7 and a starboard shaft 8. These shafts are positioned at the same distance from the centre line of the ship and right above one another in a cross ship plane 9.

In the same cross section plane 9, in the centre line of the ship is mounted a rotatory bearing column 10 above the main deck 4. On said rotatory bearing column 10 is rotationally mounted a first radial carrying arm 11 and second radial carrying arm 12. As shown, the second radial carrying arm 12 is bent at its inner end mounted on the rotatory column 10 below the first radial carrying arm 11 (see figure 2).

Coaxially around the bearing column 10 is arranged a circular rail 13, which is supported by an appropriate number of columns 14, at a height suitable for supporting the radial outer ends 15 and 16 of the two radial carrying arms 11 and 12, respectively. The two carrying arms 11, 12 thus form a part of a carousel system wherein they can rotate with the bearing column 10 as the central rotatory support, supported outermost against said circular rail 15. The two carrying arms 11, 12 can rotate independent of one another, in both directions. As a driving means many suitable devices could be used. One could, for example, consider a rotating toothed bar on the rail 15, engaged with an engine-driven cog wheel on the respective carrying arm. One could also have a central driving apparatus (in the bearing column).

On each carrying arm 11, 12 a main winch 17 is mounted for the bearing cable for the diving bell 18, two control cable winches 19 and 20 and a hoist compensator 21 for the bearing cable for the diving bell, as well as for the control cable. This is equipment which is known, per se, to a person who is skilled in the art and therefore it is neither described not shown in more detail here. It should be sufficient to mention here that the bearing cable for the diving bell 18 goes via a pulley system in the hoist compensator and to the main winch 17. Two control cables, which are weighted, go through guides connected to the diving bell 18 and via the hoist compensator to their respective control cable winches 19, 20.

In figure 2 it is suggested how the diving bell 18 is placed in a cage 23 which acts as a control means for the diving bell on its way through the shaft. Said cage 23 is suspended from the weights on the control cables. During a submersion of the diving bell 18, the control cables will be given out simultaneously with the bearing cable. The diving bell 18 and the cage 23 thus move together downwards through the shaft 7. At the bottom of the shaft the cage 23 will be stopped by a dolly which is not shown. The control cables continue downwards into the depths and will, with their guides relative to the diving bell 18, act as control cables during the dive. When the bell 18 is raised, it will move upwards being guided along the control cables and enter the cage 23 at the bottom of the shaft 7.The control cables will then be drawn in and the whole unit is thus raised through said shaft 7 until it is in the position shown in figure 2.

On the lower side of the carrying arms 11, 12 is suspended a winch 24 for the umbilical cable. All the equipment which is necessary for raising/submerging the diving bell 18 and for the supply of air and energy thereto is thus placed on the respective carrying arm, which constitutes a carrying apparatus for the diving bell on board the carrier ship.

On the between deck 6 a plurality of diving chambers 25 is arranged in a circular course, here a total of eight diving chambers. The circular course of the diving chambers 25 conforms with the circle around which the diving bells can be moved, and from the diagrams one can see that the two shafts 7, 8 are placed in the same circular course. This means that when the diving bell 18 is moved in a circular course by means of its associated carrying arm 11 or 12, the diving bell can be brought into a coupling position over a chosen diving chamber, i.e. the opening 26 in the bottom of the diving bell 18 can be brought to a coupling position above a coupling opening 27 on the selected diving chamber 25.Coupling can thus take place in a known way per se, by known coupling means, as the diving bell could be lowered towards the coupling opening 27 by means of the main winch 17 and/or by using a flexible transitionary coupling.

The pressure in the diving chamber 25 is the same as in the diving bell 18, thus the divers can, without more ado, enter the diving chamber, or vice versa. The two diving bells 18 can, as will be understood, operate entirely independent of one another. In figure 1, it is thus one of the diving bells 18 which is hanging from the carrying arm 12, coupled to a diving chamber 25 which lies below, whilst the second diving bell which is suspended from the carrying arm 11 is in the shaft 7, and may be submerged into the depths of the ocean and made operational.

In the arrangement shown, the diving machinery is arranged in the room below the between deck 6, and power leads, air pipes etc can advantageously go through the downwardly extending bearing column 10 and via suitable couplings above be apportioned to the two carrying arms 11, 12 and the apparatus arranged thereon. As the carrying arms ii, 12 will only rarely execute a complete rotation on the horizontal plane, the necessary couplings will not cause any special problems centrally, as svivel couplings and pipe loops can be used which are known to a person skilled in the art.

Each pressurized chamber 25 is, as indicated in figure 1, divided up into an upper compartment 28, the so-called wet compartment or wet room which contains a toilet, shower and changing room, and a lower compartment 29 which constitutes an accommodation compartment or living quarters.

From the above it will be apparent that the essence of the invention is that the diving chambers or living quarters are arranged in a carousel system wherein one or preferably two diving bells can sweep over all the diving chambers and be coupled to and uncoupled from these according to need and desire. The carousel system entails that the respective bell can reach any one of the chambers (with the exception of the one which happens to be coupled to the other bell).

The use of two shafts or so-called "moonpools" has been illustrated and described. One could, of course, manage with just one shaft, or optionally one large shaft which has room for two diving bells side by side. It is not required that the shafts are arranged out in the sides as shown. They can, in principle, be arranged anywhere at all, for example diametrically opposed to one another in the centre line of the ship, and one can also, as already mentioned, manage without any special shafts as the diving bell can be manoeuvered off the side of the ship or equipment carrier.

Claims

Patent Claims

1.

A diving installation comprising a carrier ship or other equipment carrier above the sea surface, a diving bell (18), a movable carrying apparatus (11, 12) for said diving bell on said equipment carrier, equipment (17, 19, 20, 22, 24) for raising/submerging said diving bell between a diving position and a coupling position on the equipment carrier, and a diving chamber assembly (25, 27) on the equipment carrier, and means (10, 13) for moving said movable carrying apparatus with said diving bell attached to and from a coupling position with the diving chamber assembly, characterized by means (10, 13) for guiding said carrying apparatus (11, 12) in a horizontal circuit, and in that the diving chamber assembly comprises a plurality of diving chambers (25) lined up in a corresponding horizontal circuit.

2.

A diving installation according to claim 1, wherein the means for guiding the carrying apparatus comprises a rotatory support (10) and a carrying arm (11, 12) mounted on said rotatory support for guiding said carrying apparatus in a circular circuit.

3.

A diving installation according to claim 2, wherein the means for guiding the carrying apparatus comprise a circular rail(13) coaxial to the rotatory support for supporting the carrying arm (11, 12).

4.

A diving installation according to any one of the preceding claims, wherein the diving chambers (25) are arranged at a horizontal level (6) below the coupling position level (4) of the diving bell on the equipment carrier, in the horizontal circular circuit of the diving bell.

5.

A diving installation according to claim 4, wherein each diving chamber has an upper wet compartment (28) and a lower accommodation compartment (29).

6 A diving installation according to any one of the preceding claims, wherein the equipment (17, 19, 29, 22, 24) for raising/submerging the diving bell (18) is placed on and is supported by the movable carrying apparatus (11, 12) for the diving bell.

7.

A diving installation according to any one of the preceding claims, and having at least one shaft (7, 8) in the equipment carrier for raising and submerging the diving bell, characterized in that said shaft (7, 8) is placed in the horizontal circular circuit of the diving bell.

8.

A diving installation according to any one of the preceding claims, wherein the diving chambers (25) are supported and fixed at a mean height in a carrier ship above the level of the diving machinery.

9.

A diving installation according to any one of the preceding claims wherein a second diving bell (18) has a corresponding second movable carrying apparatus (12), as well as means (10, 13) for guiding the second carrying apparatus in said horizontal circuit, to and from a coupling position with said diving chamber assembly.