US3800722A

US3800722A - Self-propelled, cable-supported diving bell

Info

Publication number: US3800722A
Application number: US00184432A
Authority: US
Inventors: A Lepage
Original assignee: Compagnie Francaise des Petroles SA
Current assignee: Total Compagnie Francaise des Petroles SA
Priority date: 1971-03-08
Filing date: 1971-09-28
Publication date: 1974-04-02
Anticipated expiration: 1991-04-02
Also published as: FR2128892A5; CA984686A; IT949922B; GB1345683A

Abstract

A diving bell is provided with a toric ballast tank having thin polyvinyl chloride walls. A source of compressed air and various valves are connected to the tank to control its buoyancy. Propellers are arranged on the sides of the bell to provide horizontal mobility. A control circuit measures the water level in various compartments to insure precise control of the bell''s buoyancy.

Description

United States Patent 1191 Lepage 1 Apr. 2, 1974 [54] SELF-PROPELLED, CABLE-SUPPORTED 1,541,186 6 1925 53s 114 16 R IV N L 2,357,064 8/1944 Wolf... 1. 114/16 7 3,411,304 1l/l968 Miller 293/71 R [75] Inventor: Alain M. Lepage, Marseille, France 3 1 1,02 12 1964 od m et a1, 114/16 R 173] Assignees: Comp gnie Francaise Des Petroles, 2333 #92 T11 7 5 P Com 3 nie Maritime is e f P g 3,434,443 3 1969 Estabrook... 61 69 D Expemses, Marsellle, both of, 2,981,073 4/1961 Robinson 61 69 France 3,688,720 9/1972 Lok 114/16 E Filed: Sept. 1971 3,716,009 2/1973 Strickland 114/16 E [21] Appl- 184,432 Primary Examiner-Duane A. Reger Assistant Examiner-Galen L. Barefoot [30] Foreign Application priority Data Attorney, Agent, or Firm-Sughrue, Rothwell, Mion,

Mar. 8, 1971 France 71.07865 and Macpeak [52] US. Cl 114/16 R, 114/16 E [57] ABSTRACT [51] Int. Cl. 863g 2/00 [58] Field of Search a 4/16 R 16 E 16.5, 16.7 A dlvmg bell 1s provlded with a tone ballast tank hav 114/52, 53, 54; 61/69; 73/DlG. 5; 293/71 R ing thin polyvinyl chloride walls. A source of compressed air and various valves are connected to the tank to control its buoyancy. Propellers are arranged on the sides of the bell to provide horizontal mobility.

A control circuit measures the water level in various compartments to insure precise control of the bells buoyancy.

4 Claims, 8 Drawing Figures "ATENTEUAPR 2 I974 SHEET 1 OF 5 PATENTEBAFR 2 @374 SHEET 3 OF 5 PATENTEDAPR 2|974 3.800.722

snwunrs SELF-PROPELLED, CABLE-SUPPORTED DIVING BELL BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a diving bell for submarine operations in deep water, connected to a surface vehicle by a cable. More particularly, the present invention relates to a self-propelled diving bell, capable of controlling its buoyancy.

2. Description of the Prior Art There are a large number of diving bells designed to descend depths of about 50 meters or more available in the prior art. Generally these diving bells are connected to a surface vessel by means of a cable that makes it rather difficult to move them close to the desired place of operation. Various attempts have been made to eliminate this dependency upon the surface connection. For example, in the case of a submarine petroleum well head, an auxiliary cable has been provided to guide the diving bell to the well head. Obviously a number of problems, for example the effect of marine currents and waves, reduces the effectiveness of this approach.

It has also been proposed to use a support vessel having negative buoyancy supported by a cable and intended for the transportation of heavy loads. This approach requires devices for the submarine location of the place of work and a motor which will give it access to the well in cooperation with the support or carrying vessel. The ship approaches as close as it can to the vertical position of the place of work and then, by means of a cable, lowers the carrying vessel to which the load is attached. After arriving at the desired depth, the specific location devices make it possible to direct the vessel, equipped with a motor and rudder, toward the well head where the load is to be transported. Experience, however, discloses that the movement of the vessel tied to the cable is very restricted and requires, if not the anchoring of the ship, then at least very delicate positioning correcting maneuvers.

It has also been suggested to utilize submarines. However, the operation of these boats is extremely expensive, and their weight prevents any precise and rapid maneuvering, especially since their maintenance at a certain depth below the water is achieved after adjusting the weight of the ballast by the compensation of the diving rudders as a function of the speed.

SUMMARY OF THE INVENTION A primary object of the present invention is to provide a diving bell equipped with one or more chambers and connected by a cable to a surface installation. The diving bell is made up of a water-tight body having at least one vertical symmetrical plane, with at least one pair of propellers, with one propeller arranged on either side of the symmetrical plane. A ballast tank is provided on the diving bell above the water-tight body and has at least one valve placing it in communication with the outside water and at least one compressed air inlet valve. These valves are controlled from the inside of the water-tight body in order to give the bell a positive, a negative, or a zero buoyancy, as desired.

It has been found that this kind of vessel not only has excellent maneuvering qualities making it ideally suited for easy positioning at the work site, but thatit also has great maneuvering autonomy in spite of its cable connection to the surface installation. Due to its horizontal mobility, as a result of the low power propellers, the delicate problem of operating at submarine well heads without using a fixed and expensive guide means connecting the well head to a fixed surface installation can be avoided.

A ballast tank having a toric shape at the upper portion of the bell is connected both by water inlet conduit through a valve and a compressed air inlet conduit through a second valve to control the buoyancy of the bell. A pipe is provided equipped with an escape valve to control the egress of compressed air from the tank in order to maintain a pressure equal to the outside pressure. A water evacuation pipe, equipped with a valve, is also provided with controls inside of the diving bell for controlling the various valves.

By the present invention, a diving bell is capable of reachingdepths of at least 200 meters without in any way increasing the weight of the ballast tank and without risking the implosion of the tank. In other words, it is possible to utilize a tank capable of resisting only a pressure difference on the order to several bars in order to permit the attainment of a positive, negative or zero buoyancy of the diving bell. By controlling the buoyancy, the passage of the diving bell both from and to the water surface will be optimized, since it is possible to reduce the effect of wave or current motion on the bell by rendering a negative buoyancy.

BRIEF DESCRIPTION OF THE DRAWINGS Other advantages and features will emerge from the following specification, given here with reference to the attached drawings which, by way of example, represent one way of implementing the present invention FIG. 1 represents a front schematic view of the diving bell;

FIG. 2 is the plan view of the bell of FIG. 1;

FIG. 3 is a cross-section through the ballast tank made along section line IIIIlI in FIG. 2, as well as a partial sectional view of the diving bell;

FIGS. 4a 4d disclose the various operational states of the diving bell; and

FIG. 5 shows the ballast tank level indicator circuit.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring to FIGS. 1 and 2, the body of the diving bell comprises a cylinder 1 equipped with a bulging upper cover 2, a bulging lower cover 3, a lower chamber 4 and a side chamber 5.

Two pairs of propellers, 6, 8 and 7, 9 are assembled into a bulb-shaped configuration. The lower propellers of each pair are attached so that the center of gravity of the bulb-shaped assembly will be above the center of gravity of the bell. These propellers are arranged symmetrically with respect to the axis of the cylindrical body 1. This particular propeller arrangement offers great maneuverability which is further enhanced by permitting each propeller to be run forward or back ward. The electric motor control devices and their appropriate contact circuit breakers are well known in the art and accordingly will not be discussed here. In addition, the control buttons or handles inside the diving bell have not been shown because these various elements do not contribute to the present invention. The groups of propellers are made in one piece with the body I, by means of attachment pieces Il14 which themselves are in one piece with the

post members

15 and 16.

Rings

17 and 18 encircle the body cylinder 1 and carry shock absorber edges or flanges l9 and 20 made of polyvinyl chloride, for example, to protect the diving bell against any possible shocks. These rings, which are made in one piece with the bell, can also be made in one piece with the

post members

15 and 16.

A clip or ear 21, on the axis of the upper bulging cover 2, provides means for attaching a cable 22 to the diving bell.

The ballast tank 23 is made up of three water-tight compartments separated by

inside partitions

24, 25 and 26, as disclosed in FIG. 2. This sub-division makes it possible to prevent the effects that would occur if the liquid could heave or swell in the inside of the tank during the course of maneuvering. Each of the compartments is made of four tube elements, such as 27-30. These pipes or tubes can be hot-air welded polyvinyl chloride members. The ring-shaped configuration formed by these members is capable of resisting the relatively large internal and external pressures generated during the operation. The thickness of the partitions 24-26, can be 7 millimeters. The compartments are identical, and accordingly, only the compartment formed by

walls

24 and 25 will be presently described. An elbow tube 31 leading into the upper portion of the ballast tank 23 is connected to a valve 32 controlled from the inside of the water-tight diving hell by means ofa hand wheel 33 and a rod 34. When the valve 32 is opened, water is let into the ballast tank. Rod 34 is preferably made of an inoxidable steel or a stainless steel and runs through the hull by any suitable means, such as a tightness adapter 35. The tube 31 can be made of polyvinyl chloride. Valve 32 can include a ball shutter and can also be made of polyvinyl chloride. The water contained in the compartment can be evacuated through pipeline 36 under the control of valve 37, which in turn, is controlled by an inside hand wheel 38.

Compressed air can be admitted into the ballast tank through pipeline 39, which includes a valve 40 which is controlled by hand wheel 41. The valve 40 is connected to the compressed air tank 42.

A circuit makes it possible to maintain the pressure prevailing inside the ballast at the value of the external pressure. For this purpose, a circuit provides a connection between the interior of the ballast tank 23 and a pressure regulator valve 43, which is located externally to both the cylinder 1 and the ballast tank 23. The pressure regulator valve 43 is connected to a high pressure escape valve 45 by means ofa flexible hose 44, and the high pressure escape valve 45 is, in turn, connected to blocking valve 46 by pipeline 47. Valve 46 is connected to a compressed air tank 48.

As shown in FIG. 3, the water level in the ballast tank is controlled by means of the float 49, which supports two permanent magnets 50. The float moves along rod 51 containing magnetically controlled contacts and resistances of a measurement circuit shown in FIG. 5. The transmission wires 52 connect the detector 53 to the level indicator 54 which in fact, and as explained hereinafter, is an appropriately labeled voltmeter. In order to reduce the movements of float 49 resulting from the movements of the water contained in the ballast tank, the float is surrounded by a damping tube 55 having two small holes 56 and 57, one near its base and the other in the upper portion. A duct 49a makes it possible to balance the pressure between the inside portion of the float and its environment. The float is guided vertically by a stretched wire 58.

Tube 55 is welded directly to the inside wall of the ballast tank. Tube 51 contains the various apparatus circuits and is one piece with stopper 59 being held in position on the threaded piece 60 with the help of a milled button 61.

Supports such as 62, serving as support for the protection rings 17 and 18, are also used in order to attach the ballast tank 23, as shown in FIG. 1. For this purpose, threaded rods 63 pass through tubes 64 welded to the ballast tank 23.

Screws

65 and 66 tighten the appropriate washers which are supported respectively against the ballast tank 23 and the support 62.

The ballast tank 23 includes three compartments and, as illustrated in FIG. 5, three identical water level indicator circuits. These circuits are mounted parallel to the power supply circuit made up of transformer 67 and serving respectively voltmeters 54, 54A, and 548. Because of the identity of the circuits, it is only necessary to describe the circuit associated with voltmeter 54.

Referring to FIG. 5, in the absence of water, contact C to C which are each inserted in series with the resistances R and R10, are cut off from any electrical connection between the power supply wire 69 and the terminal 70. Voltmeter 54 thus indicates the zero value for the water level in the corresponding compartment.

When the compartment is filled, float 49 as shown in FIG. 3 moves along tube 51 and its magnets 50 successively close the contacts which are opposite the magnets. The greater the number of closed contacts, the greater the number of resistances connected in parallel and the greater the voltage at the terminal 70 of voltmeter 54.

By this control circuit, the operator of the diving bell knows at any moment the water level of each compartment and by virtue of this fact, he also knows the weight of the ballast and can thereby easily perform the maneuvers which he wants to perform as a function of the depth that he wishes to reach.

During the operation of lowering the diving bell into the water, the

valves

32 and 37, as shown in FIG. 4a, are opened to provide a negative buoyancy to the bell tank. The

air inlet valves

40 and 46 are kept closed as the water rises in the compartments and drives the air out through 32.

Knowing the desired weight which is necessary for descent, the water level is regulated in the ballast tank compartments by closing water inlet valve 32, FIG. 4b, and by opening water evacuation valve 37, and by introducing, with the help of valve 40, a volume of compressed air until the desired water level is reached. At this point, the

valve

40 and 37 will again be closed.

During the course of descent,

valves

32, 37 and 40, as shown in FIG. 40, remain closed, but valve 46 will be open in order to permit the pressure regulator valve 43 to restore the pressure within the ballast tank to that existing outside. Thus, in spite of a light weight structure, capable of resisting only a few barspressure, it is possible to prevent the implosion of the ballast tank regardless of the depth reached.

When it is desirable to raise the diving bell, the inverse operation can be performed. In this operation, the

valves

32 and 37 will be opened before reaching the surface as shown in FIG. 4d in order to reduce the effects of the surge on the diving bell and in order to facilitate the extraction of water from the diving bell.

The winch control for the lowering or raising of the cable from the ship or surface installation forms no part of the present invention and, accordingly, is not described or shown. It is obvious that any known winch device can be used to control the reeling up or unreeling of the cable in response to an order transmitted automatically or otherwise from the diving bell.

By virtue of the constant control which can be exercised by the operator, increasing or decreasing the buoyancy of the diving hell, it is further possible to increase or reduce the length of the cable while moving the bell horizontally with the help of a portion or an assembly of the two pairs of propellers. Moreover, each propeller bulb group is capable of running forward or backward, and the vessel has great maneuverability by virtue of the lateral arrangement of the motors and can turn about its own axis or assume various inclinations. Due to the particular arrangement, it is possible to achieve extremely large horizontal displacements that have not heretofore been capable of being achieved from a diving bell suspended from a fixed surface installation, while utilizing only a propeller power on the order of a few horsepower.

By way of example, for an apparent zero weight of the diving bell as a result of the manipulation of the buoyancy, it is possible for a cable-connected diving bell where the cable has an apparent weight of about 4 kg/m to navigate over a circle with a radius of 1 m at a depth of 150 m. Under the samecondjti or1 s, bu t with a lighter cable of about 1.7 kg/m, the bell can increase its active radius to 160 m for the same cable length of 200m at a depth of 110 m.

Various modifications can be effected by a person skilled in the art within the scope of the present invention, and accordingly, the present invention should be measured solely from the following claims.

What is claimed is:

l. A diving bell comprising:

1. a water-tight body symmetrical about a vertical plane;

2. a pair of propellers both of which are mountedon the water-tight body in positions above the center of gravity of the bell and one of which is located on each side of the plane of symmetry;

3. means for rotating said propellers independently of each other in either direction, which means are controlled from within the water-tight body;

4. a ballast tank positioned on top of the water-tight body and subdivided into a plurality of compartments;

5. means for controlling the buoyancy of the ballast tank, said means including:

a. a first outlet means providing fluid communication between the upper portion of the ballast tank and the exterior of the diving bell;

b. a first valve located in said first outlet means and adapted to control fluid communication through said first outlet means;

c. means located within the water-tight body for controlling said first valve, whereby water may be let into the ballast tank by an operator located within the water-tight body;

. a second outlet means providing fluid communication between the lower portion of the ballast tank and the exterior of the diving bell;

e. a second valve located in said second outlet means and adapted to control fluid communication through said second outlet means;

f. means located within the water-tight body for controlling said second valve, whereby water may be evacuated from the ballast tank by an op-' erator located within the water-tight body and employing also a first source of compressed air to be recited;

a first source of compressed air;

afirstpath of fluid communication between said first source of compressed air and the .ballast tank;

i. a third valve located in said first path of fluid communication and adapted to control fluid communication between said first source of compressed air and the ballast tank;

j. means located within the water-tight body for controlling said third valve, whereby compressed air may be supplied to the ballast tank by an operator located within the water-tight body, thereby forcing water out said second outlet means;

k. a second source of compressed air;

I. a second path of fluid communication between said second source of compressed air and the ballast tank;

m. a fourth valve located in said second path of fluid communication and adapted to control fluid communication between said second source of compressed air and the ballast tank;

n. means located within the water-tight body for controlling said fourth valve, whereby the passage of compressed air through said second path of fluid communication may be blocked by an operator located within the water-tight body;

0. a pressure regulator valve located in said second path of fluid communication externally to both the water-tight body and the ballast tank and adapted to block the passage of compressed air through said second path of fluid communication when the pressure inside the ballast tank is equal to or greater than the pressure outside the diving bell; and

p. an indicator of the level of the water inside the ballast tank, said indicator being readable inside the water-tight body,

whereby an operator located within the water-tight body can control the horizontal motions of the diving bell by means of the above-recited propellers and the vertical motions of the diving bell by means of the above-recited means for controlling the buoyancy of the ballast tank while said pressure regulator valve prevents the ballast tank from being imploded by external pressure. 7

2. A diving bell as claimed in claim 1 wherein said indicator of the level of the water inside the ballast tank comprises:

1. a float carrying a magnet;

the interior of the ballast tank, whereby the surging effect of the water in the tank is dampened.

4. A diving bell as claimed in claim 2 wherein 1. the diving bell further comprises a pair of rings encircling the water-tight body and carrying shockabsorbent flanges to protect the diving bell against shocks, one of said rings being located immediately below the ballast tank and the other of said rings being locatednear the bottom of the diving bell, and 2. the ballast tank is mounted on and supported by the upper of said rings.

Claims

1. A diving bell comprising: 1. a water-tight body symmetrical about a vertical plane; 2. a pair of propellers both of which are mounted on the watertight body in positions above the center of gravity of the bell and one of which is located on each side of the plane of symmetry; 3. means for rotating said propellers independently of each other in either direction, which means are controlled from within the water-tight body; 4. a ballast tank positioned on top of the water-tight body and subdivided into a plurality of compartments; 5. means for controlling the buoyancy of the ballast tank, said means including: a. a first outlet means providing fluid communication between the upper portion of the ballast tank and the exterior of the diving bell; b. a first valve located in said first outlet means and adapted to control fluid communication through said first outlet means; c. means located within the water-tight body for controlling said first valve, whereby water may be let into the ballast tank by an operator located within the water-tight body; d. a second outlet means providing fluid communication between the lower portion of the ballast tank and the exterior of the diving bell; e. a second valve located in said second outlet means and adapted to control fluid communication through said second outlet means; f. means located within the water-tight body for controlling said second valve, whereby water may be evacuated from the ballast tank by an operator located within the water-tight body and employing also a first source of compressed air to be recited; g. a first source of compressed air; h. a first path of fluid communication between said first source of compressed air and the ballast tank; i. a third valve located in said first path of fluid communication and adapted to control fluid communication between said first source of compressed air and the ballast tank; j. means located within the water-tight body for controlling said third valve, whereby compressed air may be supplied to the ballast tank by an operator located within the water-tight body, thereby forcing water out said second outlet means; k. a second source of compressed air; l. a second path of fluid communication between said second source of compressed air and the ballast tank; m. a fourth valve located in said second path of fluid communication and adapted to control fluid communication between said second source of compressed air and the ballast tank; n. means located within the water-tight body for controlling said fourth valve, whereby the passage of compressed air through said second path of fluid communication may be blocked by an operator located within the water-tight body; o. a pressure regulator valve located in said second path of fluid communication externally to both the water-tight body and the ballast tank and adapted to block the passage of compressed air through said second path of fluid communication when the pressure inside the ballast tank is equal to or greater than the pressure outside the diving bell; and p. an indicator of the level of the water inside the ballast tank, said indicator being readable inside the water-tight body, whereby an operator located within the water-tight body can control the horizontal motions of the diving bell by means of the above-recited propellers and the vertical motions of the diving bell by means of the above-recited means for controlling the buoyancy of the ballast tank while said pressure regulator valve prevents the ballast tank from being imploded by external pressure.

2. a pair of propellers both of which are mounted on the water-tight body in positions above the center of gravity of the bell and one of which is located on each side of the plane of symmetry;

2. the ballast tank is mounted on and supported by the upper of said rings.

2. a plurality of magnetically-operated electrical contacts mounted in the ballast tank at predetermined levels therein and electrically connected in parallel;

3. a source of electrical current connected in series to said plurality of magnetically-operated contacts; and

3. A diving bell as claimed in claim 2 wherein said float is positioned within a damping tube the interior of which is in fluid communication with the remainder of the interior of the ballast tank, whereby the surging effect of the water in the tank is dampened.

4. a voltmeter connected in series to said source of electrical current and to said plurality of magnetically-operated contacts, said voltmeter being readable inside the water-tight body.

4. A diving bell as claimed in claim 2 wherein

5. means for controlling the buoyancy of the ballast tank, said means including: a. a first outlet means providing fluid communication between the upper portion of the ballast tank and the exterior of the diving bell; b. a first valve located in said first outlet means and adapted to control fluid communication through said first outlet means; c. means located within the water-tight body for controlling said first valve, whereby water may be let into the ballast tank by an operator located within the water-tight body; d. a second outlet means providing fluid communication between the lower portion of the ballast tank and the exterior of the diving bell; e. a second valve located in said second outlet means and adapted to control fluid communication through said second outlet means; f. means located within the water-tight body for controlling said second valve, whereby water may be evacuated from the ballast tank by an operator located within the water-tight body and employing also a first source of compressed air to be recited; g. a first source of compressed air; h. a first path of fluid communication between said first source of compressed air and the ballast tank; i. a third valve located in said first path of fluid communication and adapted to control fluid communication between said first source of compressed air and the ballast tank; j. means located within the water-tight body for controlling said third valve, whereby compressed air may be supplied to the ballast tank by an operator located within the water-tight body, thereby forcing water out said second outlet means; k. a second source of compressed air; l. a second path of fluid communication between said second source of compressed air and the ballast tank; m. a fourth valve located in said second path of fluid communication and adapted to control fluid communication between said second source of compressed air and the ballast tank; n. means located within the water-tight body for controlling said fourth valve, whereby the passage of compressed air through said second path of fluid communication may be blocked by an operator located within the water-tight body; o. a pressure regulator valve located in said second path of fluid communication externally to both the water-tight body and the ballast tank and adapted to block the passage of compressed air through said second path of fluid communication when the pressure inside the ballast tank is equal to or greater than the pressure outside the diving bell; and p. an indicator of the level of the water inside the ballast tank, said indicator being readable inside the water-tight body, whereby an operator located within the water-tight body can control the horizontal motions of the diving bell by means of the above-recited propellers and the vertical motions of the diving bell by means of the above-recited means for controlling the buoyancy of the ballast tank while said pressure regulator valve prevents the ballast tank from being imploded by external pressure.