US3593530A

US3593530A - Marine platform with removal column clamps

Info

Publication number: US3593530A
Application number: US843331A
Authority: US
Inventors: Ivo C Pogonowski
Original assignee: Texaco Inc
Current assignee: Texaco Inc
Priority date: 1969-07-22
Filing date: 1969-07-22
Publication date: 1971-07-20
Anticipated expiration: 1988-07-20

Abstract

The invention relates to a marine platform adapted to be fixedly positioned in an offshore environment by anchoring to the ocean floor. The platform includes a work deck normally elevated above the water''s surface, a foundation pedestal at the ocean floor, and one or more intermediary support columns which connect the deck to the pedestal. The columns are releasably held at their lower ends by remotely actuated clamping means. The elevated deck is thus supportably carried by the columns at an adjustable operating height.

Description

United States Patent Inventor lvo C. Pogonowski Houston, Tex. Appl. No. 843,331 Filed July 22, 1969 Patented July 20, i971 Assignee Texaco Inc.

New York, N.\".

MARINE PLATFORM WITH REMOVAL COLUMN CLAMPS 9 Claims, 9 Drawing Figs.

U.S.Cl. 6l/46.5, 24/243 Int. Cl E02b 17/06 FieldotSearch 61/465; 24/243,263

a" \L 1 5'7 #7}; t 3/ i J4 t 33 e 36 i, i s /6 g t v 5 N s h s w 23 i 5 1 e i [56] References Cited UNITED STATES PATENTS 2.969 648 l/l96l Rechtin 6l/46.5 3,201,945 8/1965 Sutton 61/465 Primary Examiner-Jacob Shapiro Attorneysl(v E Kavanagh and Thomas H. Whaley ABSTRACT: The invention relates to a marine platform adapted to be fixedly positioned in an offshore environment by anchoring to the ocean floor. The platform includes a work deck normally elevated above the waters surface, a founda- I I I I I I I I g I,

WIIIIIIA'IA MARINE PLATFORM WITII REMOVAL COLUMN CLAMPS BACKGROUND OF THE INVENTION In the exploration for and producing of oil from offshore locations, one form of platform adapted for the purpose is firmly anchored to the ocean floor at the drilling site. After completion of the work the platform is detached and removed to an alternate site for further use. Because of the great expense necessitated in the building and installation of such platforms the feature of the platform being versatile and transferable is virtually mandatory. 7

In one type of platform the individual platform components include a deck, foundation member, and support members are readily separable to facilitate both the initial installation, and subsequent movement of the unit. Normally, the connecting legs or columns which support the working deck above the water's surface are fixedly connected to the under water pedestal, and operably engaged by elevating jacks at the column upper ends.

In the course of transferring a marine platform between drilling sites, the topography of the ocean floor can vary such that often the platform, if permitted to rest on the floor, will assume a nonhorizontal attitude. This cantihg of the foundation member is reflected and amplified in the disposition of the upwardly extending legs which in turn cause the deck to be similarly tilted.

ln overcoming this contingency of unevenness at the ocean floor, one expedient is to permit the support legs to extend downwardly through the pedestal whereby the latter is in effect maintained or raised a predetermined distance above the ocean floor. The respective support legs are then piled into the substratum thus fixedly anchoring the foundation at a desired angle. The nonnal mode for fastening support legs to an ocean -'floor mounted platfonn pedestal, is to cement or grout the lower ends of the legs into an appropriate receptacle at the pedestal whereby to form an elongated rigid collar about each support leg. In such an instance, when it becomes necessary to release and move the platfonn, the fixedly positioned legs pose a problem. T

In the instance of platforms in relatively deep offshore waters, the structures are substantially equivalent to those used in shallow water. However in the instance of deep water units, the installation and removal of the platform usually has to be achieved without substantial diver assistance such that the operations are virtually all accomplished by remote control. Further at such time as the platform is to be removed, it is often necessary in complying with governmental regulations, that the piling or platform leg be severed beneath the ocean floor such that no portion thereof extends upwardly from said floor. As above mentioned in the instance of a deep water installation, the disengagement of the platform from its anchor ing piles beneath the ocean mud line can introduce a substantial number of problems both operationally and economically.

OBJECTS OF THE INVENTION It is therefore one of the objects of the invention to provide a versatile marine platform adapted to be readily transferred between successive drilling sites. A further object is to provide a platform of the type described including means for readily detaching the platform from an anchored position. A still further object is to provide a marine platfonn including a plurality of separably connected units whereby to facilitate movement of the platform. Still another object is to provide a remotely operated releaseable clamping means for engaging a support column. A still further object is to provide a columnclamping means carried on a marine pedestal of the type contemplated, said clamping means being adapted to grip or release a column as required.

In overcoming the foregoing problems and achieving the herein stated objectives, there is provided a novel marine platform for use in relatively deep water and adapted to be transferred from one water depth to another. The invention in brief contemplates such a problem adapted to be fixedly anchored in a body of water for drilling offshore wells or the like. The platform includes a floatable work deck which accommodates equipment for carrying out the platform's purpose. 'A foundation pedestal disposed beneath the deck rests at or adjacent to the ocean floor and is fastened in place by piling or similar means. One or more, and preferably a plurality of elongated columns depend upwardly from the pedestal in a substantially vertical attitude and operably engaged the deck such that the latter might be elevated or lowered as needed. A remotely ac- BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 illustrates a marine platform of the type contemplated anchored at an offshore location.

FIG. 2 is a segmentary view of a part of the platform shown in FIG. I, when positioned at an alternate location characterized by a sloping ocean floor.

FIG. 3 is a segmentary view shown in cross section and on an enlarged scale, of a portion of the platform pedestals shown in FIG. I and 2. I

FIG. 4 is a segmentary view in cross section on an enlarged scale taken through line 4-4 in FIG. 1.

FIG. 5 is a cross sectional view taken along line 55 in FIG. 4. 'FIG. 6 is a segmentary view on an enlarged scale and cross section of an alternate embodiment of the apparatus shown in FIG. 4.

FIG. 7 is a segmentary view on an enlarged scale taken along line 7-7 in FIG. 4.

FIG. 8 is a segmentary view of an alternate embodiment of the clamping band shown in FIGS. 4 and 5.

' FIG.9 is an end view of the band shown in FIG. 8. I

Referring to FIG. I, the platform 10 wherein the present device is incorporated includes is a desk 11 which in its normal working attitude is elevated 50 or 60 feet above the water's surface. Deck 11 is preferably so fabricated so as to be buoyant to permit being floated into place with or without the accompanying legs and pedestal. Deck 11 in the usual manner is provided with necessary equipment for drilling or producing a well such as a derrick l2, draw-works and the like. Deck 11 also is provided with a jacking mechanism which receives the upper end of asupport column whereby the platform can adjust its height above water by movement along the leg.

A pedestal 13 functions as a foundation member, and is normally positioned at or near the ocean floor whereby reform a base to the platform. Said pedestal 13 includes a plurality of corner members 1 4, 16 and-I7 which are generally elongated, open ended tubular sleeves having a conical guide piece 18 carried at the upper end to facilitate entry of a leg-orcolumn as the latter is lowered from deck II. The respective column members are utilized by a series of structural elements such as

horizontal cross beams

19 and 21 which are reinforced by a lattice work of brace members 22. The entire structure thus forms an open foundation element characterized by a relatively wide base in comparison with the size of deck 11.

A plurality of support columns or

legs

23, 24 and 26 extend upwardly'from pedestal 13 to a position beyond the waters surface. The column upper. ends register in comer jacks which, although not shown, are carried'in deck 11 whereby the latter might be adjusted by elevating itself along the fixedly positioned upright columns. Said support columns are preferably of substantially equal length. However, as is frequently the instance, the contour of the ocean floor does The support columns here shown as being three, are not so limited in number but are designed in accordance with the depth of water, the conditions at a particular area such as the water currents and above surface weather, and the loading factor contributed by the deck. Preferably, the support columns are formed of heavy gauge steel being shaped into cylindrical sections which are either preformed to a desired column length, or welded together at the drilling site in accordance with the length of column to be utilized. The latter may further incorporate a buoyancy element such as surface controlled flotation tanks in their structure whereby the disposition of the column in the water might be regulated to facilitate assembling the platform.

As shown in FIG. 3, the lower end of leg 23 extends downwardly from its corner sleeve 16 in the direction of the ocean floor. Column 23 may be partially imbedded at its lower end into the floor a predetermined depth, or maintained above and the mud line. In either instance, column 23 is provided with a plurality of downwardly extending piles 27 which are driven into the substratum beneath pedestal 13 to fixedly establish the position of each column with respect to the ocean floor. Said piles 27 after being imbedded, are cementedv or grouted into the column 23 lower end in the usual manner as by forming a rigid cement collar about the leg column.

In accordance with the invention, each comer member or sleeve of the anchor pedestal is provided with peripheral column gripping means adapted to releasably grasp the outer surface of the column with a sufficient hold to prohibit relative longitudinal movement between the column and the surrounding comer member 16.

As shown in FIG. 4 the column gripping mechanism is incorporated within the pedestal structure in a manner to form a locking grip about the column 23 at both the upper and lower ends of comer member 16. Said gripping means includes in essence a semirigid continuous collar or band like 31 which is sufiiciently flexible to wrap around the periphery of a column 23 and be drawn tightly thereabout by applying tension to opposed ends of the band. Collar 31 may be shaped of a unitary metallic band preformed into a loop configuration with the desired diameter to accommodate a particular column size.

Collar 31 may also as shown in FIGS. Sand 9, comprise an assembly of wire cable so arranged as to form the necessary loop like configuration about the column 23. In either instance one or more positioning and retaining brackets 32 are fixed to band 31, which brackets includes a vertically depending tang 33 which extendsoutwardly from the band and-registers within a slot 38 in leg 23 whereby to provide outboard support for collar 31 when thelatter is in column-gripping position.

Collar 31 is upwardly supported particularly when in the column-gripping position, by an annular shoulder piece 36 depending from the inner wall of corner member 16. The upper rubbing force of shoulder piece 36 provides a bearing surface slidably engaging and supporting the underside of band 31 in both the contracted and expanded positions. Said shoulder piece 36, together-with the bracket 32 thus distributed the weight of column 233 when the latter is gripped. An annular neck 37 is disposed on the inner wall of comer sleeve 16, having a central opening 38 defined by inwardly tapered sidewalls and being adapted to register a downwardly moving leg 23 as the latter is lowered into the comer member upper end.

Referring again to FHGS. 4 and 5, in the instance of a three column platform as shown in FIG. 1, horizontal cross beam 19 and 190 are welded to the substantially upright corner sleeve 16 defining an internal angle of 120. A gusset plate 39 is provided therebetween forming a corner reinforcement between the respective horizontal crossbeams and the said corner member 16 to assure rigidity at the pedestal joint.

Referring to FIGS. 4 and 7, a rubbing shoe depends from the inner wall of crossbeam l9. Said shoe 41 us provided with a contact'face bounded by

upstanding rims

42 and 43 adjacent to said surface, the intermediate space being adapted to slidably engage the outer side of band 31 whereby the latter is supportably guided by said shoe 4].

The end of collar 31 is turned back on its length to define a loop of sufficient diameter to receive a pin connector 44. The latter pivotally engages a connecting yoke 46 at the extremity of arm 47 which is operably connected to a motor means 48. I

The latter includes a power source such as an electric motor or a hydraulic unit both of which are actuated through control lines extending from the motor means to the supported deck 11. The gripping or releasing action on a column may thereby be regulated from the deck as required.

' column 23. Opposed ends of the band 31 are thus slidably drawn across the respective rubbing shoes 41 to maintain band 31 in alignment with the motor means in each of beams 19 and 19'. Similarly upon reverse actuation, arm 46 is urged toward leg 23 whereby causing the band 31 to relax its grip on volumn 23. The latter may then he slid horizontally through corner sleeve 16 as for a relocating or anchoring operation.

Motor means 48 is preferably disposed in axial alignment.

with the enclosing crossbeam l9 and removably connected to a transverse panel 51 whereby the motor means is supportably maintained within the crossbeam. in the event of needed repair, replacement of the motor means in whole or in part, access to the cross beam interior is achieved through one or more openings formed in the wall and provided with removable enclosures.

As herein mentioned, the described column-gripping apparatus and arrangement within the crossbeams is definitive of the mechanism at one comerof the pedestal; Such locking means is preferably provided at the remaining upper and lower corners of the pedestal. Each support column is thereby firmly gripped at spaced apart intervals near the lower end sufficiently tight to rigidize the column with respect to the pedestal. Additional similar clamping devices may be provided alongthe length of thecomer member 16 is accordance with the capability of band 31 to provide a sufficient grasp and upward support to column 23.

FIG. 6 illustrates an alternate embodiment of the columngripping arrangement within a pedestal corner formed by the upstanding corner sleeve 56, the intersecting and

interconnected crossbeams

57 and 58, and the uprightly held support column 59. In this instance, comer sleeve 56 is provided with an open ended tubular casing 61 connected to an opening formed in the wall of said sleeve 56 and disposed substantially normal to the latter. A backing plate 62 is carried at the open end of casing 61 to form a lateral wall against which column 59 is urged to maintain the latter is place. A collar 63 comprises an elongated metal band as herein described with respect to the embodiment at FIGS. 4 and 5. Said band includes a tang 64 fastened to the outboard end of the collar which tab slidably engages an aperture formed in the sidewall of corner sleeve to provide lateral support. A bending shoe 66 formed on the inner wall of casing 61 slidably engages the surface of collar 63 to align said member with the horizontally movable actuating structure 67 of the motor means 68.

Said motor means 68 is rigidly carried within the casing 61 at a backwall 69 to position said motor means in place.

As in the instance of the previously described embodiment, actuation of motor means causes collar 63 to be drawn into locking engagement by virtue of being drawn taut from anchoring post 71. On backup plate 62 the said tightening of the collar thereby frictionally engages the collar and the column whereby to form a tight connection. As in the embodiment shown in FIG. 5 a shoulder piece 72 depending from the inner wall of corner member 56 supports the gripping band against longitudinal movement thereof when in the gripping position.

It will be apparent from the foregoing description that the method is subject to other modifications without departing from the scope of the invention as defined in the following claims.

lclaim:

1. An elongated marine platform adapted to be mounted in a substantially upright position and fixed to the floor of a body of water, said platform including:

a working deck elevated above the waters surface,

a foundation pedestal at the lower end of said plafiorm and including means to anchor said platform to the floor of said body of water,

at least one upstanding support column extending from said foundation pedestal to the waters surface and being operably engaged with said working deck,

said foundation pedestal including column-gripping means at the lower end of said at least one upstanding support column to permit controlled longitudinal movement of the latter with respect to said column-gripping means, and means for remotely actuating said column-gripping means, to control said column movement,

said column-gripping means including a continuous bandlike clamp member retained on said pedestal and operable between contracted and expanded positions to permit controlled vertical movement of such columns when said bandlike clamp member is in the expanded condition, and

motor means connected to at least one of said clamp member for adjusting said member between said contracted and expanded conditions.

2. In the apparatus as defined in claim 1 wherein said clamp member includes a semirigid band having opposed ends, and being formed to define an opening having a loop configuration of a sufficient diameter to register a support column in said loop configuration opening.

3. In the apparatus as defined in claim 2 wherein said semirigid band includes motor means attached to opposed ends thereof, the latter being simultaneously actuable to adjust said clamp member between the expanded and contracted positions whereby to adjust said loop configuration opening into tight engagement with the outer surface of said column.

4. In an elongated marine platform adapted to be uprightly fixed to the floor of a body of water and including;

a deck normally positioned above the surface of said body of water,

a pedestal anchored to the floor of said body of water for firmly positioning said platform, and

a plurality of support columns extending uprightly between said deck and said pedestal in connecting relation to said pedestal,

the latter including a plurality of upstanding cylindrical sockets having axial openings therethrough to slidably receive a support column,

at least two brace members laterally connected to the respective cylindrical sockets and opening into the latter to define a mutual connecting joint therebetween,

clamp means positioned at said mutual connecting joint and including, a gripping band having opposed ends and being formed into a loop of sufficiently large opening to receive a column passed therethrough,

motor means connected to at least one end of said band to actuate the latter between gripping and releasing positions by applying an actuating force to said band whereby to control the sliding movement of said column through said cylindrical socket.

5. in the apparatus as defined in claim 4 including motor means connected to said opposed ends of said band whereby to simultaneously apply an actuating force to said band opposed ends.

6. In the apparatus as defined in claim 4 wherein said motor means is fixedly positioned in said laterally disposed brace members.

7. In the apparatus as defined in claim 4 wherein said clamp 'means includes a plurality of gripping bands spaced longitudinally along said socket to grip said column at space-apart sections of the latter.

8. in the apparatus as defined in claim 4 including bearing means carried on said cylindrical socket in engagement with saig grip ing band to vertically support the latter.

n t e apparatus as defined in claim 8 wherein said bearing means includes an annular shoulder piece having an upper rubbing surface, depending from wall of said socket said shoulder extending radially inward to form a passage whereby to receive a support column, and said band slidably and supportably engaging said rubbing surface.

Claims

1. An elongated marine platform adapted to be mounted in a substantially upright position and fixed to the floor of a body of water, said platform including: a working deck elevated above the water''s surface, a foundation pedestal at the lower end of said platform and including means to anchor said platform to the floor of said body of water, at least one upstanding support column extending from said foundation pedestal to the water''s surface and being operably engaged with said working deck, said foundation pedestal including column-gripping means at the lower end of said at least one upstanding support column to permit controlled longitudinal movement of the latter with respect to said column-gripping means, and means for remotely actuating said column-gripping means, to control said column movement, said column-gripping means including a continuous bandlike clamp member retained on said pedestal and operable between contracted and expanded positions to permit controlled vertical movement of such columns when said bandlike clamp member is in the expanded condition, and motor means connected to at least one of said clamp member for adjusting said member between said contracted and expanded conditions.

4. In an elongated marine platform adapted to be uprightly fixed to the floor of a body of water and including; a deck normally positioned above the surface of said body of water, a pedestal anchored to the floor of said body of water for firmly positioning said platform, and a plurality of support columns extending uprightly between said deck and said pedestal in connecting relation to said pedestal, the latter including a plurality of upstanding cylindrical sockets having axial openings therethrough to slidably receive a support column, at least two brace members laterally connected to the respective cylindrical sockets and opening into the lAtter to define a mutual connecting joint therebetween, clamp means positioned at said mutual connecting joint and including, a gripping band having opposed ends and being formed into a loop of sufficiently large opening to receive a column passed therethrough, motor means connected to at least one end of said band to actuate the latter between gripping and releasing positions by applying an actuating force to said band whereby to control the sliding movement of said column through said cylindrical socket.

7. In the apparatus as defined in claim 4 wherein said clamp means includes a plurality of gripping bands spaced longitudinally along said socket to grip said column at space-apart sections of the latter.

8. In the apparatus as defined in claim 4 including bearing means carried on said cylindrical socket in engagement with said gripping band to vertically support the latter.

9. In the apparatus as defined in claim 8 wherein said bearing means includes an annular shoulder piece having an upper rubbing surface, depending from wall of said socket said shoulder extending radially inward to form a passage whereby to receive a support column, and said band slidably and supportably engaging said rubbing surface.