US3845634A

US3845634A - Dual hydro winch lift mechanism

Info

Publication number: US3845634A
Application number: US00412380A
Authority: US
Inventors: E Rosenberg; S Moran
Original assignee: US Department of Navy
Current assignee: US Department of Navy
Priority date: 1973-11-02
Filing date: 1973-11-02
Publication date: 1974-11-05
Anticipated expiration: 1991-11-05

Abstract

A pair of compartmented cylinders provide buoyant support for a huge, heavy, undersea structure. After the compartmented cylinders and structure have been towed to the work site, flooding and evacuating selected compartments in each of the cylinders rotates them in opposite directions. When the cylinders have cleared the downward projection of the structure, it is lowered to the bottom by continued flooding and evacuating of the compartments. By rotating one of the cylinders a greater or lesser degree than the other, the undersea structure is aligned in a vertical or a desired angular relationship with respect to the bottom. The compartmented cylinders function as the supporting member for the undersea structure during construction, as a transport vehicle to the work site, and as the mechanism for deploying the structure to the bottom.

Description

United States Patent [191 Rosenberg et al.

DUAL HYDRO WINCH LIFT MECHANISM Inventors: Edgar N. Rosenberg; Stephen F;

Moran, both of San Diego, Calif.

The United States of America as represented by the Secretary of the Navy, Washington, DC.

Filed: Nov. 2, 1973 Appl. No.: 412,380

Assignee:

US. Cl 61/465, 114/ .5, 1 14/51 Int. Cl. B63c l/06, B63b 35/00 Field of Search 61/465, 69, 1, 46, 82;

References Cited UNITED STATES PATENTS 5/1962 Sims 61/82 9/1968 Rosenberg et al. r 114/51 9/1972 Koehler 61/46.5

[ Nov. 5, 1974 Primary Examiner-Jacob Shapiro Attorney, Agent, or FirmRichard S. Sciascia; Ervin F. Johnston; Thomas Glenn Keough [57] ABSTRACT A pair of compartmented cylinders provide buoyant support for a huge, heavy, undersea structure, After the compartmented cylinders and structure have been towed to the work site, flooding and evacuating selected compartments in each of the cylinders rotates them in opposite directions. When the cylinders have cleared the downward projection of the structure, it is lowered to the bottom by continued flooding and evacuating of the compartments. By rotating one of the cylinders a greater or lesser degree than the other, the undersea structure is aligned in a vertical or a desired angular relationship with respect to the bottom. The compartmented cylinders function as the support 'ing member for the undersea structure during construction, as a transport vehicle to the work site, and as the mechanism for deploying the structure to the bottom.

8 Claims, 10 Drawing Figures PAIENTEMV 5mm suns: 10$ 3 FIG.5

ARRA VCINC WRATPQINC PLl/C/lg/VC THE H CYLINDERS CABLES STRUCTURE CONS TRUC T INC THE STRUCTURE SECURING ROgi/T/VC v LOMggf/ZJ/VG TH i's CYLINDERS STRUCTURE FLOOD/NC AND 6 EVACUATl/VC THE COMPAIRTME/VTS FIGIO 1. DUAL HYDRO wINcII LIFT MECHANISM STATEMENT OF GOVERNMENT INTEREST The invention described herein may be manufactured and used by or for the Government of the Unites Statesof America for governmental purposes without the payment of any royalties thereon or therefor.

BACKGROUND OF THE INVENTION With the increasing interest in the development of undersea minerals and marine farming, for example, extensive undersea complexes are being designed. Construction and deployment of verylarge, bulky structures continues to-present a formidable task. Usually, the structures are put together on a dry dock or launching ways. When they are completed, large barges or a good number of pontoons ferry the structure to a desired site. Once-there, the barges or pontoons are flooded to lower the structure to the bottom, or giant cranesplay out interconnected cables until the structure was on the bottom. Both these approaches are fraught with danger and failure. The air space remaining in partially flooded pontoons becomes more and more compressed with increasing depth and hence, the pontoonss buoyancy steadily dimenishes, causing the structure to. hit the bottom with considerable impact. Most rigid, barge-like flotation members collapse at depthand the structures would slam into the bottom. This damages the structures and poses a great hazard to divers orother workmen watching the deployment from a nearby submersible. Pressure compensating the pontoons has been relied upon to .control the rate of descent; however, the labryinth of gas hoses reaching from the array of pontoonsneeded to support a large, undersea structure greatly complicates the deployment procedure. Furthermore, since there is a limit to the size and lifting capabilities-of heavyduty ocean going vanced phase of deployment of the tower.

cranes, massive undersea structures or towers cannot be deployed as a unit. Usuallysubassemblies are linked together "on a piecemeal basis by divers in'relatively shallow waters. Thus, there is a continuing need in the state-ofsthe-art for structure which provides a method for deploying heavy, bulky,- undersea structures on the oceans bottom and which is capable of orienting the structures when so deployed in a number of attitudes.

SUMMARY OF THE INVENTION The present invention is directed to providing a method for deploying an elongate, undersea structure.

Two buoyant, compartmented cylinders are arranged in a spaced, parallel relationship and each have at least one cable wrapped about itself. The elongate structure is placed on top of both the buoyant compartmented cylinders and transported to the work site. Sincethe cables are connected at opposite endsto the buoyant compartmentedcylinders and the undersea structure,

It is another object of the invention to provide a method for transporting a large, undersea structure.

Still another object is to provide a method for constructing, transporting, and deploying a huge, bulky, undersea structure.

Another object is to provide a method for ensuring a controlled rate of descent and placement of a huge, undersea structure on the oceans floor.

Still another object is to provide a method for ensuring the proper orientation of an undersea structure on the bottom.

These and other objects of the invention will become more readily apparent from the ensuing description when taken with the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is an isometric depiction of an undersea structure in construction enroute the deployment site.

FIG. 2 is a cross-sectional end view. of the invention showing the initial phase of deployment. I

FIG. 3 is a cross-sectional end view of the invention showing an advanced phase of deployment.

' FIG. 4 is an end view of the invention showing the undersea structures in place.

FIG. 5 is a bottom view of a modification of the invention.

FIG. 6 shows theinvention in transport and about to deploy an elongate tower.

FIG. 7 is an end view of the invention showing the initial phase of deployment of the tower.

FIG. 8 is anend view of the invention during an ad- FIG. 9 is an end view of the invention during the phase of deployment as the tower rests on the bottom.

FIG. 10 is a block diagram of the operation of this invention.

- DESCRIPTION OF THE PREFERRED EMBODIMENTS The ever increasing interest in exploiting the oceans for their minerals or as a food source continues to build as the world population continues to soar. Toward this end, research efforts have called for the deployment of massive, undersea structures near shore or out at extreme depths. These structures are evisioned as enclosing mining operations or serving as the boundaries for a marine animal culture. Prior to the inception of this invention, the size of an integral undersea structure was limited, since no method could safely handle the massive, weighty structures needed for todays ocean floor ventures.

Referring now to the drawings, FIG. 1 depicts an ocean going tug l0 towinga huge, undersea structure 20 to a work site. A pairof elongate, compartmented

cylinders

30 and 40 buoy up undersea structure 20 and serve as flotation members to allow the transport of the structure to the deployment site. Buoyed in such a manner, the compartmented cylinders also function to support the structure during its construction. Alternately, if the structure is fabricated elsewhere, e.g. on a dry dock, the cylinders are flooded to sink beneath thestructure and then purged of water to buoy the structure above the surface of the water.

Wrapped about each of the compartmented cylinders is a plurality of heavy-

duty cables

31 and 41. The bitter end of each of the cables is connected to its respectively associated compartmented cylinder, while at the distal ends they are secured to

anchor points

21 and 22 on the underside of the undersea structure. These cables are of sufficient lengths to reach to depths in excess of 1,500 feet to ensure the proper placement of the structure.

The exact configuration of each of the compartmented cylinders is substantially identical to the "Floatable Hoisting Apparatus of Edgar N. Rosenberg, as fully disclosed in his US. Pat. No. 3,228,37l issued Jan. l l, 1966. The physical construction of

compartmented cylinders

30 and 40 contains the sumps and pumping-valve network of the Rosenberg Apparatus. A plurality of compartments 32 through 39 and 42 through 49 are schematically depicted in the present drawings as functionally equivalent to the compartments of the Rosenberg Apparatus.

Locating a pair of

compartmented cylinders

30 and 40 beneath the structure having diameters of l50 feet and being approximately 300 feet long, would provide a sufflcient buoyant force to support a weight of up to 12,000 tons.

After the cylinders and platform have been towed to the work site and are or on-station, the procedure for deploying the undersea structure is begun. First, the compartmented cylinders are displaced from the underside of the undersea structure to clear the downward projection of the structure. This is accomplished by flooding and evacuating selective ones of the compartments, noting FIG. 2. Water is pumped into

compartments

34, 35, and 36 of cylinder 30 and compartments 45, 46, and 47 of cylinder 40. The other compartments remain evacuated. Oppositely directed rotational motion and lateral travel by both of the compartmented cylinders commences in the directions indicated by the small arrows. The weight, or rather, the lack of buoyancy now provided by

compartments

34 and 35 and 46 and 47 rotates compartmented cylinder 30 in a clockwise direction and compartmented cylinder 40 in a counterclockwise direction. Simultaneously the buoying force created by the evacuated

chambers

37 and 44 impart respective clockwise and counterclockwise additive torques to either compartmented cylinder 30 re 40. As these additive torques are exerted by both of the cylinders, they unwind their

cables

31 and 41 in opposite directions along the bottom of the undersea structure.

Care must be exercised at this point to strictly control the rate of travel of the rotating cylinders. If the cylinders are going too fast as they roll past the corners a and 20b of the structure, the structure will be dropped into the water and possibly be damaged. During the transition around corners 20a and 20b, the roll-by must be uniform and prevent a lessening of the gradual by the cylinders. To elaborate, to rotate each of the cylinders from beneath the structure requires the creation of torsional forces which are opposite in direction to the torque needed to support the platform by

cables

31 and 41. Therefore, the transition from rotational forces in one direction to rotational forces in the opposite direction must be gradual to avoid a diasterous dumping of the structure into the water. One way to avoid this is to fill all the compartments on one side of each compartmented cylinder. As the cylinders roll from beneath the platform there will be a sufficient counteracting torque to offset the weight of the platform.

After the cylinders have rolled from beneath the structure, the structure is immersed in the water, see FIG. 3. With water filling compartments 35, 36, 37, and 38 of cylinder 30 and compartments 43, 44, 45, and 46 of cylinder 40, a controlled descent begins. Continued rotation of the cylinders by progressively flooding successive ones of the compartments on the right hand side of cylinder 30 and flooding successive ones of the compartments on the left hand side of cylinder (and oppositely in cylinder 40), lowers the undersea structure gently to the ocean floor. By synchronizing the rate of rotation of both of the compartmented cylinders, the horizontal orientation of undersea structure 20 is maintained throughout deployment until the structure rests on the bottom. When the structure is so disposed,

cables

31 and 41 optionally are severed or a suitable disconnect at anchor points 21 and 22 isactuated to permit retrieval of the cable.

An increased buoyancy capability and control of descent is ensured by the embodiment depicted in FIG. 5 in which there are two sets of parallel

compartmented cylinders

30 and 40. The deployment sequence is substantially the same as aforediscussed, yet with this embodiment, much greater loads can be borne. The transport capability of this embodiment is somewhat impaired, however.

The present invention can also be advantageously employed to orient an undersea structure in a different attitude. An elongate tower 50 is carried to the work site by a pair of

compartmented cylinders

30 and 40. At the work site compartments 34, 35, and 36 are flooded and cylinder 30 begins to rotate in a clockwise direction. Compartmented cylinder 40, on the other hand, is maintained in a stationary position and for this purpose compartments 45 and 46 are flooded to provide ballast. After cylinder 30

rounds corners

50a and 50b, the cylinder is reballasted by flooding

compartments

35, 36, 37, 38. This produces an upward lifting force on cable 31 and as water is evacuated from chamber 38 into chamber 34 a clockwise rotation begins and tower 50 is lowered to the position shown in FIG. 7. This unwinding compartmented cylinder 30 rotates compartmented cylinder 40 since it is secured by its cable 41 to an anchor point 52. After the tower has been oriented and a vertical attitude, see FIG. 8, water is flooded into

chambers

45, 46, 47, and 48. Now, water is pumped into chamber 34 and evacuated from chamber 38 of cylinder 30 and flooded to chamber 49 and evacuated from chamber 45 of cylinder 40. The tower continues toward the ocean floor.

At this point it may be considered advisable to resecure line 31 to anchor point 53 to expedite the lowering of the tower. Finally, noting F IG. 9, the tower is shown resting on the ocean floor and all that need be done is to disconnect

cables

31 and 41.

What has thus far been described is a method for ensuring the placement of huge, ackward, undersea structure in a desired attitude. The compartmented cylinders serve as a dry dock during construction of the undersea structure, serve as a transport vessel to the deployment site and as the vehicle for deploying the cltructure safely and. without damage on the ocean oor.

Looking to FIG. 10, this entire sequence is schematically portrayed. First, there is the arranging of the cylinders in a parallel relationship. The wrapping 61 of at least one cable about each cable follows next. Placing 62 the undersea structure on top of the parallel cylinders follows in sequence, although provision is made for the constructing 63 of the structure on the spaced compartmented cylinders.

Securing 64 the cables at opposite ends to a compartmented cylinder and the undersea structure ensures that, upon the rotating 65 of the cylinders, by flooding and evacuating 66 the compartments that there will be a lowering 67 of the elongate undersea structure to the bottom by the continued rotation of each buoyant compartmented cylinder.

By merely making the compartmented cylinders larger and larger, massive structures can be constructed, transported, and deployed. Concrete, which heretofore was too heavy for such massive structures, now may be used as the principal building material. Thus, long term substantial structures are a reality, due to the novel method herein disclosed.

Obviously,vmany modifications and variations of the present invention are possible in the light of the above teachings, and, it is therefore understood that within the scope of the disclosed inventive concept, the invention may be practiced otherwise than specifically described.

What is claimed is: l. A method for deploying an elongate undersea structure comprising:

arranging at least two buoyant compartmented cylinders in a spaced parallel relationship; wrapping at least one cable about each buoyant compartmented cylinder; placing the elongate structure to rest on the top of each buoyant compartmented cylinder; securing opposite ends of each cable to a buoyant compartmented cylinder and the elongate under.- sea structure; rotating each buoyant compartmented cylinder to position each buoyant compartmented cylinder outside the downward projection of the elongate undersea structure; and lowering the elongate undersea structure to the bottom by continued rotation of each buoyant compartmented cylinder. I 2. A method according to claim 1 further including:

transporting the elongate undersea structure to the work site prior-to said rotating.

3. A method according to claim 2 in which said rotating attributed to the steps of flooding and evacuating selective compartments in both the buoyant compartmented cylinders.

4. A method according to claim 3 in which said flooding and evacuating are in a sequence to ensure clockwise rotation in one buoyant compartmented cylinder and counterclockwise rotation in the other buoyant compartmented cylinder.

5. A method according to claim 4 in which said rotating of both buoyant compartmented cylinders is substantially simultaneous in time and equal in' rate and duration to deploy the elongate undersea structure in a horizontal relationship with respect to the bottom.

6. A method according to claim 4 in which said rotating of one buoyant compartmented cylinder is first in time and longer in duration than the other buoyant compartmented cylinder to deploy the elongate undersea structure in a vertical relationship with respect to the bottom.

7. A method according to claim 4 in which said arranging includes a first set and a second set of two buoyant compartmented cylinders, said first set being orthogonally disposed with respect to said second set.

ing is the construction of an elongate undersea structure on the buoyant compartmented cylinders.

l l l

Claims

1. A method for deploying an elongate undersea structure comprising: arranging at least two buoyant compartmenteD cylinders in a spaced parallel relationship; wrapping at least one cable about each buoyant compartmented cylinder; placing the elongate structure to rest on the top of each buoyant compartmented cylinder; securing opposite ends of each cable to a buoyant compartmented cylinder and the elongate undersea structure; rotating each buoyant compartmented cylinder to position each buoyant compartmented cylinder outside the downward projection of the elongate undersea structure; and lowering the elongate undersea structure to the bottom by continued rotation of each buoyant compartmented cylinder.

2. A method according to claim 1 further including: transporting the elongate undersea structure to the work site prior to said rotating.

5. A method according to claim 4 in which said rotating of both buoyant compartmented cylinders is substantially simultaneous in time and equal in rate and duration to deploy the elongate undersea structure in a horizontal relationship with respect to the bottom.

8. A method according to claim 4 in which said placing is the construction of an elongate undersea structure on the buoyant compartmented cylinders.