US2960832A

US2960832A - Submergible barges with anchor spuds

Info

Publication number: US2960832A
Application number: US530816A
Authority: US
Inventors: Hayward John Thomsen
Original assignee: Individual
Current assignee: Individual
Priority date: 1955-08-26
Filing date: 1955-08-26
Publication date: 1960-11-22
Anticipated expiration: 1977-11-22

Description

Nov. '22, 1960 J. T. HAYWARD 2,960,832

SUBMERGIBLE BARGES WITH ANCHOR SPUDS 2 Sheets-Sheet 1 Filed Aug. 26, 1955 a 9 17 l /7 -6 I] I,

INVENTOR.

J. T. HAYWARD SUBMERGIBLE BARGES WITH ANCHOR SPUDS Nov. 22, 1950 2 Sheets-Sheet 2 Filed Aug. 26, 1955 IN V EN TOR.

7.' Hayward United States Patent .SUBMERGIBLE BARGES WITH ANCHOR SPUDS FIohn Thomsen Hayward, Hayward-Wolff Research Corporation, 122 Bayside Drive, 'Clearwater, Fla.

Filed Aug. 26,1955,.Ser.'No.' 530,816

13 Claims. (Cl. 61-465) This invention relates to improvementsin submergible hulls,;particularly submergible .drilling barges employed .for drilling in open ocean areassuch as .alongsthe .Continental Shelf lining the Gulf of Mexico.

.Submergible barges are now being employed fordr'illing in open ocean water overlying the Continental Shelf and in similar open water areas. Such barges ordinarily. com- .prisea hull, a wave-transparent superstructure generally "consisting of a number of spaced'columns, and a working. platform supported on the columns at a height above the'bargehullisuch that the workingplatform will fbe a'abovethecrests of any waves which 1 maysordinarily .be anticipated in the area of operation whentheihullis rest- .ing :.on the underlying .subnatant land bottom. Such barge hulls ordinarily have :a;flat .bottomito lprovidean extended spread footing in COHtQOLWlth'Ihe surfaceofthe submerged land in orderto provideafirmfoundationifor the working platform and theload imposed. thereon.

' One 'of the problems encountered in .connection' with :such submergible'barges is the .tendency of such barges to movelaterally over the. land surface under the forces of wind and wave acting on the superstructure, or of unfderwater currents exerted against the submerged hull. Various means have been employed to anchor the barge to "the land to prevent this lateral movement which can prove very hazardous to drilling operations conducted from such a barge-supported platform.

One such anchor means which has been used comprises a plurality of spuds which'are passed throughopenings in the barge and into'the underlying land. This arrangement while generally efiective to prevent. lateral movement of the hull, is nevertheless subject to considerable difliculty arisingfrom the clearance-which isordinarily present between the cylindrical spud surface and the wall of the hull opening in order to provide free "movement of the spud through the'opening. By reason of this clearance, even though small, a small amount of lateral movement of the hull. relative. to the spuds can occur. .As a result, slight shifting of the hull will cause the spud to bind against thehull at'the corners corresponding to the upperv and lower ends of the hullopenings. Thetremendous forces involved may often hint -or bend the spuds at the pointsof contact with the hull and will make very difficult the later withdrawal of the spuds in order to release the 'hullifor re-floating and movement to other locations.

The present invention contemplates improvements'in tthe spud anchoring structure to obviatethe difliculty, mentioned above, arising withconventionalspud anchoring constructions.

In accordance with the present invention, the portions of the spuds passing'throughihe openings and .the snr- -rounding walls of the openings are shaped to define ibetween them co-operating downwardly tapering frusto- -conical surfaces which will serveto seat the spuds .inthe hull openings in-such-a manneras to maintaincontinuous engagement between the spuds and 'the'hull. This Will prevent relative movement betweenthese members and thereby obviate the difiiculty mentioned above,-while at the same time permitting easy withdrawal.

The .taperedsurfaces contemplated by the "present invention-may be obtained by providing hull openings having.downwardlytapering frusto-conical shape and by forming the portion of thespudpositioned withinsuch an opening with a complementary shape. Other suitable arrangements may be employed to provide thedesired tapered: seating surfaces, as will appear hereinafter.

f-Another conditionencountered in marine drilling-with .submergible hulls'of the .kind described is a small oscillatory or :rocking movement of the hull which frequently occurs when the hull is resting on'the submerged land. It is thought thisrocking movement isdue tothe .slight'elasticity whichappears-to be characteristic of the soft land bottoms .underlying off-shore waters in many localities. As the-submergedhull is of substantial length, very often .a-wave will be passing above one end of the hull while simultaneously a trough may be'above the opposite end of the hull. The greater head of water 'represented'by the wave will, byreason of the slight elasticity of thesupporting land, tend to press the underlying portion of :thebarge downwardly slightlywhile the lesser head of water over the opposite end of the hull will "allow the latter to.riseslightly, this movement being alternated and repeated asasuccession of wavespass over the submerged hull.

.Where-spuds'are' employed to anchor the 'hull to-the land bottom, this oscillatory or rocking movement tends to produce :aloosening-of the 'spuds in the underlying groundand thus reduce the anchoring effectiveness of the spuds. The -fpresent invention contemplates additional modifications which vwill obviate this condition while .simn'ltaneous ly.mai-ntaining secure seating engagement of -the spuds in the hull.

In accordancewith these additional embodiments, one or more resilient spacer or filler rings or sleeves, constructed of rubber for otherresilient composition material, are concentrically interposed 'between the spud and the wall of the opening through which the: spud passes. The innerandouter-peripheries of thesespacer or filler elements are-shaped to complement the-adjacent surfaces 30f therspud'and the hull-opening-to provide the tapered .seat surfaces tforthe spud 'andhullopening which will .provide.the continuously: maintained contact between the :spud and"the-wall ofthe opening adapted to prevent lateral'movement between the hull and the spuds. At the same time, by their resilient construction, the filler devices will absorb-therocking movement, produced as above described, andthereby prevent loosening of the spud in .the underlying ground.

Accordingly, it is a primary object of this invention to provide in combination with a submerged hull, means for effectively anchoring the hull to the land surface on which it rests.

A further, object is to provide a hull constructionhaving spud receiving openings therein and spuds passing through said openings into .the underlying ground, the spuds and openings having co-operating engaging surfaces adapted to prevent lateral movement between thethull and the spuds.

An additional object is to provide anchoring means for submerged hulls which include openings through the hull and spuds extending through the openings, there'be- Zing resilient fillers between the adjacent surfaces of the spuds and the openings adapted to absorb oscillatory amovement of the hull relative to the spuds.

Another object is to provide an anchoring arrangementemploying one or more resilient filler rings disposed vin .ahull openingbetween the opposedwallsurfaces of the hullopening and thespud passing therethrough at leastonetof theopposed surfaces being downwardly 3 tapered and the tiller rings having peripheral faces engaging both said surfaces and complementary in shape thereto. v v a A more specific object is to provide an anchoring means including a plurality of spaced-apart downwardly tapering frusto-conical openings through a submerged hull and a spud passing through each opening, each spud having a downwardly tapering frusto-conical portion complementary to the shape of the hull opening whereby to fit snugly therein. 1

Other and more specific objects and advantages of this invention will become more fully apparent from the with the accompanying drawing which illustrates several useful embodiments in accordance with this invention.

In the drawing: 7 I Fig. 1 is a side elevational view of a generally conventional form of submergible drilling barge, showing a number of anchoring spuds passing through the hull portion thereof into the underlying submerged land;

Fig. 2 is a plan view looking downwardly along line following detailed description when read in conjunction Fig. 3 is an elevational view of one embodiment of a I I spud form and related seating structure in a hull opening;

Fig. 4 is an elevational view, generally similar to 'Fig. 3, illustrating another embodiment in accordance with the present invention;

1 Fig. 5 is a view looking downwardly along line 5-5 1 and the upper end of the structure shown in Fig. 4; and

Figs. 6 and 7 are views similar to Figs. 3 and 4 of still other embodiments in accordance with the present invention.

Referring to the drawing, there is shown 'in Figs. 1 i

and 2a generally conventional form of submergible drilling barge, designated generally by the numeral 1,

which-includes a generally rectangular hull, designated generally by. the numeral 2, having a substantially flat bottom 3, deck 4, and end and side plates 6 and -7, :7

respectively. The hull may also be provided with a slot 8 in one end, commonly termed a drilling slot, through which the drilling tools are projected in the underlying ground. A plurality of tubular columns 99 are secured tothe hull to extend vertically above the hull deck. The

columns support on their upper ends a working platform 10 on which is mounted a conventional drilling derrick 10a positioned over the drilling slot 8. The height of columns 9 will be made such that when the hull is resting on the subnatant land L beneath the surface of a water body W, the working pl tform 10 will be elevated at a sufi'icient height above the normal water level to clear the crests of any waves which might occur in the area'in which the barge structure is being used. The

number of columns 9 and their spacing will ordinarily be such as to provide a maximurn degree of wave transparency through the superstructure supporting the work- 'ing platform. The molded depth of the hull. that is, the

height from bottom 3 to deck 4, will ordinarily be from r about 10 to 15 feet.

It will be understood that hull 2 will be suitably come partmentecl and rovided with conventionalballast transferring and handling gear for sinking and re-floating the barge structure, such equipment and arrangements being well understood'by those skilled in the art and form no part of the present invention. *It will also be understood that'by the use of conventional operating procedures and .means, the hull may be submerged to rest on the 12- -12 are inserted through openings '11 into land I; to

the embodiments of Figs. 3 and 4.

penetrating qualities.

4 effectively anchor the hull against lateral movement relative to the land.

Openings 11 and the portions of spuds 12 enclosed within the openings 11 are designed, as illustrated in Figs. 3 and 7. to prevent or reduce lateral movement between the hull and the spuds once the latter have been inserted through the openings into the underlying land. As illustrated in Fig. 3, opening 11 is defined by a wall 13 which is shaped to provide a downwardly tapering frusto-conical opening through the hull. Spud 12 is ordinarily of tubular construction having its upper end portion 14 ofdownwardly tapering frusto-conical shape complementary to the shape of opening 13, so that as the spud is inserted through opening 13 and into the underlying land, opening 13 will form a seat for portion 14 of the spud which will provide maintained engagement between the spud and the hull at all times to thereby prevent any lateral movement of the hull relative to the spud. The lower or anchor portion 15 of the spud which projects into the underlying land may be made cylindrical, but is preferably made with a slight downward and inward taper throughout its length, the downward taper of

portions

14 and 15 making insertion of the spud into the underlying ground relatively easy, and also enabling the spud to be withdrawn from the land and from the seat formed'by opening 11 with minimum effort. The lower end of the spud is closed and may be provided with a pointed tip 16 to enhance its ground The spud may be provided with an elongate stem 17 connected to its upper end and projecting upwardly through the working platform 10.

By the use of this stem, the spud may be pushed downwardly through opening 11 into the underlying land and retracted therefrom when desired by operations conducted from the working platform.

The length of portion 15 is preferably made from about one to about two times the molded depth of the hull. Thus, in a case of a hull having a molded depth of 10 feet, for example, portion 15 will have a length .of from 10 to 20 feet, this range in length relative to themolded depth of the hull being found generally sufficient to effectively anchor the hull to the underlying land.

With the described arrangement, it will be seen that as the. spud is forced into the land and tapered portion ,14 is fed through tapered opening 11, the spud will become tightly seated in the hull and lateral movement of the hull relative to the spud will be effectively prevented. At the same time owing to the taper of the spud it will be immediately freed from the hull upon the application of an upward force.

Figs. 4 and 5 illustrate a modification of the structure shown in Fig. 3. As it is sometimes difiicult to shape the hull plates so as to provide a suitably tapered opening 11, the embodiment shown in Fig. 4 will provide a practical alternative while still retaining the tapered seating connection between the hull and the spud. In this embodiment opening 11a. is generally vertically straight or .cylindrical. Secured to wall 13a, which defines opening 11a, is a plurality of radially inwardly projecting, angularly spaced ribs 18 having their inner edges sloped downwardly and inwardly to collectively define a downwardly tapering frusto-conical passage 19. The frustoconical passage thus defined provides the seat for recelving tapered portion 14 of spud 12 in the same manne as in the embodiment illustrated by Fig. 3. a

It will be understood that other structural arrangements may be employed, it being necessary only that they provide the downwardly tapered co-operating seating surfaces corresponding functionally to those illustrated by Figs. 6 and 7 illustrate further embodiments which retain the ta ered seating engagement between the hull and the spuds while at the same time providing means for absorbing small rocking or oscillatory movements of accuses the hull, suchasthose heretoforedescribed, in order to obviate the loosening effect which such movement might otherwise have upon spuds which are directly engaged with-the hull.

In Fig. 6, hull 2 is provided. with a vertically straight opening 111: to receive a spud corresponding in external form to spud 12 of the previously described embodiments; that is, the spud being provided with a frustoconical downwardly tapering upper section 14 and an anchor section 15 having the point 16. Since opening 11b is substantially cylindrical'whileportion 14 of the spud is downwardly tapering, there'is provided between the surfaces of wall 13b and spud portion 14 a downwardly diverging annular space 20. interposed in this annular space is a sleeve member 21 of massive resilient construction, made of rubber. or similar resilient material, having its outer periphery. 22 cylindrical in shape to conform to the cylindrical shape of opening 11b and having its inner periphery 23 downwardly tapering frustoconical shape complementing in shape spud portion 14. The sleeve 21 thus provides a flexible resilient spacer or filler member which provides the tapered seat in the opening for receiving the tapered spud to thereby maintain continuous engagement between the spud and the hull. The upper and lower ends of opening 11b may be provided with inwardly projecting

annular flanges

24 and 25, respectively, to serve as stops or keepers to prevent sleeve 21 from being drawn or pushed out of opening 11b. Sleeve 21 is made slightly shorter in length than the distance between

flanges

24 and 25 to provide a small amount of axial movement of the sleeve in opening 11b to allow effective seating of the spud in the hull opening and to allow the spud to be readily released when it is to be withdrawn. Sleeve 21 may be hollow, having the internal chamber 26 which, however, is filled with liquid in order to prevent collapse of the sleeve under pressures due to the hydrostatic head of the sea above the hull. Although the liquid in chamber 26 is incompressible and renders the sleeve structure as a whole incompressible, the resilience of the walls of the sleeve will allow deformation to absorb the slight oscillatory or rocking movements of the hull relative to the spud while, at the same time, maintaining the continuous engagement between the spud and the hull necessary to prevent substantial lateral movement of the hull relative to the spuds.

Fig. 7 illustrates an arrangement employing the resilient spacer elements which provide an alternative arrangement to that illustrated in Fig. 6. As shown in Fig. 7, the hull is provided with the downwardly tapering frustoconical opening 11c defined by correspondingly shaped wall 130. Spud portion 14a, which extends through opening 110, is made vertically straight instead of tapered, as in the previously described embodiments, thus again providing an annular space c between the opposing surfaces of the spud portion 14:: and wall 13c. In this case, the space thus provided is downwardly converging. Interposed between spud portion 14a and wall 13c are two vertically spaced upper and lower filler rings 27 and 28, respectively. These rings are of massive resilient construction made from rubber or similar resilient composition. The peripheries 29 and 30, respectively, of the upper and lower rings define coaxial vertically straight cylindrical surfaces complementing the cylindrical surfaces of spud portion 14a. The

outer peripheries

31 and 32, respectively, of the upper and lower rings are made downwardly and inwardly tapering to define downwardly tapering frusto-conical surfaces complementing the shape of opening lie. The thickness of the filler rings 27 and 28 is made such as to provide continuous engagement between opposing surfaces of spud portion 140 and wall 13c. Keeper flanges 33, 34 project from wall 13c inwardly of opening 110 above and below upper ring 31 and

similar keeper flanges

35 and 36 enclose lower filler ring 28, the keeper flanges being spaced somewhat from the adjacent ends of the related rings to permit limited axial'movernent of the rings in the openings.

With the arrangement shown in Fig. 7', it will be seen that a vertically straight spud may be inserted through the bores defined by the inner-peripheral surfaces 29 and 30 of the filler rings. As it is moved downwardly through opening the friction between the spud'and the filler rings will urge them downwardly along the inner-faceofwvall 13c and will produce a wedging action between the spud andthe wall. of. the opening, thus rings 27 and 28 become, in efiect, resilient wedges. This embodiment is particularly useful where the spud, as it moves downwardly through the underlying land, encounters relative hard formations, such that it might be impracticalto employ a form such as illustrated in Figs. 3 and 4-.which would require .sufiicient downward movement to seat the tapered spud portions 14 fully in the tapered seats in the hull. With the embodiment illustrated in Fig. 7, downward movement of the spud to any extent will produce the wedging action between the spud and the hull, which will effectively prevent substantial lateral movement of the hull relative to the spud while, at the same time, providing a degree of resilience in the connection which will absorb the previously described rocking or oscillatory movement of the hull.

It will be understood that the spuds in each of the several embodiments may be equipped with stems, such as stem 17, for forcing the spuds into the underlying land; Fig. 6 illustrates an alternative arrangement useful particularly in cases where the underlying land is quite soft, as is frequently the case in various points along the Gulf Coast. In this modification, the spud may be filled with a weighting material, such as concrete 35, which will provide sufiicient weight to cause the spud to move downwardly the requisite distance under its own weight. Chains 36 may be connected to the upper end of the spud and extended to the working platform to permit withdrawal of the spuds when it is desired to move thebarge.

Another efiective way of causing the spuds to penetrate the land underlying the hull is to ballast it by introducing sea water to the interior thereof in any convenient manner, as through extension or stem 17. Similarly, the removal of the spuds may be facilitated by de-ballasting. To do this, air may be introduced in any suitable and known manner to the interior of the spud and the pressure thereof employed to eject the ballast through a pipe 17a, shown in broken lines in Fig. 3, which extends through the interior of the spud to a point near its lower end and has its upper end fitted with a check valve 17b and communicating with the Water body exteriorly of the spud.

The number of spuds employed for any barge and their spacing and locations in the hull may be varied widely, depending upon the dimensions of the hull, the character of the land bottom, and other conditions encountered in the areas of employment of the barge. In some cases, only a few spuds may be required, and in others a relatively large number. In many cases it may be preferable to group the spuds in the center portion of the barge but, as noted, their particular locations and spacing will depend upon the conditions encountered and the circumstances of each individual case. The spuds, themselves, may be of varying dimensions, so far as diameter is concerned, diameters of three to six feet being a generally satisfactory size. Their length will depend generally upon the molded depth of the hull, as previously noted.

It will be understood that various other alterations and modifications may be made in the details of the illustrative embodiments within the scope of the appended claims but without departing from the spirit of this invention.

What I claim and desire to secure by Letters Patent is:

l. In combination with a submerged hollow hull resting on a subnatant land surface and having vertically spaced upper and lower walls, at least one generally vertical'op'ening extending entirely through the hull including said walls, and an elongate spud member extending from above the surface of the water body in which the hull is submerged through said opening into anchoring engagement in the underlying land, the opposing portions 'of the spud member and the wall of said opening being relatively shaped to define cooperating downwardly tapering frusto-conical seating surfaces operable when engaged to prevent relative lateral movement between thehull and the spud member and to facilitate withdrawal of the spud member. 1 l

2. In combination with a submerged hollow hull resting on a subnatant land surface and having vertically spaced upper and lower walls, a plurality of generally vertical openings extending entirely through said bull including said walls in laterally spaced-apart relation, and elongate spud members extending from above the surface of the water body in which the hull is submerged through said openings into anchoring engagement in the underlying land, the opposing portions of said spud members and the walls of said openings being relatively shaped to define cooperating downwardly tapering frustoconical seating surfaces operable when engaged to prevent relative lateral movement between the hull and the spud members and to facilitate withdrawal of the spud members.

3. In combination with a submerged hollow hull resting on a subnatant land surface and having vertically spaced upper and lower walls, a plurality of generally vertical openings extending entirely through said hull including said walls in laterally spaced-apart relation, and elongate spud members extending from above the surface of the water body in which the hull is submerged through said openings into anchoring engagement in the underlying land, said openings being downwardly and inwardly tapered to provide frusto-conical seats, said spud members having upper frusto-conical portions receivable in said seats and having lower anchor portions projecting from said seats into the underlying land surface.

4. A structure as defined by claim 3 wherein the lower portions of said spud members have a length of from one to two times the molded depth of said hull.

5. A structure as defined by claim 3 wherein said lower portions of said spud members are of downwardly tapering frusto-conical shape.

6. In a structure as defined by claim 3, means connected to the spud members for inserting and extracting them into and out of said openings.

7. In combination with a submerged hull resting on a subnatant land surface, a plurality of generally vertical openings extending entirely through said bull in laterally spaced apart relation, and elongate spud members extending through said openings into anchoring engagement in the underlying land, the opposing portions of said spud members and the walls of said openings being relatively shaped to provide a frusto-conical annular space therebetween, and resilient ring means positioned in said space in resilient wedging engagement between said opposing portions of the spud members and the walls of said openings.

8. A structure as defined by claim 7 wherein said resilient ring means comprises a longitudinally tapered sleeve member constructed of resilient non-metallic position material shaped to conform to the shape of said annular space. i

9. A structure as defined by claim 7 wherein saidresilient ring means comprises a pair of longitudinally spaced tapered rings constructed of, flexible, non-metallic composition material. 1 10. In combination with a submerged hull resting on a subnatant landsurface, a plurality of generally vertical openings extending entirely through said hull in laterally spaced-apart relation, and elongate spud members extending through said openings, into anchoring engage ment in. the underlying land, said openings being defined byvertically straight cylindrical walls, the portions of said spud members enclosed within said openings having downwardly tapering frusto-conical shape, and means positioned withinsaid openings forming seats comple mentary in shape to said portions of the spud member. j 11. A structure as defined by claim 10 wherein said means comprises a plurality of longitudinally extending angularly spaced ribs secured to the wall of each of said openings to project radially inwardly therefrom, the inner longitudinal edges of said ribs sloping downwardly and inwardly with respect to the 'axis of said openings to complement the taper of said spud portions.

12. Anchor means for a submerged hull resting on a subnatant land surface, comprising in combination with a hull having a spud-receiving opening extending generally vertically therethrough, said spud and the wall of said opening having cooperating surfaces shaped to prevent lateral movement between the spud and the hull, and resilient filler means interposed between said surfaces to absorb oscillatory movement of the hull relative to the spud. I

13. Anchor means for a submerged hull resting on a subnatant land surface, comprising in combination with a hull having a spud-receiving opening extending generally vertically therethrough, a hollow elongate spud member closed at its lower end extending from above the surface of the water body in which the hull is submerged through said opening into the underlying land, said spud member and the walls of said opening having cooperating engaging surfaces of downwardly tapering frusto-conical shape to prevent lateral movement between the hull and the spud member, the portion of the spud member ex: tending below the hull opening into the underlying land being downwardly and inwardly tapered to facilitate its withdrawal from said land, and means for ballasting and de-ballasting the spud member operable respectively to force it into said land and to facilitate its withdrawal therefrom.

References Cited in the file of this patent UNITED STATES PATENTS 953,051 Muralt Mar. 29, 1910 1,673,639 Madge June 12, 1928 2,237,387 Crites Apr. 8, 1941 2,318,685 Gross May 11, 1943 2,367,146 Siebs Jan. 9, 1945 2,554,288 Ainsley May 22, 1951 2,675,681 Dawson Apr. 20, 1954 2,687,017 Gerwick Aug. 24, 1954 2,688,848 Moon Sept. 14, 1954