US3021680A - Submergible drilling barge with hull protective devices - Google Patents

Description

Feb. 20, 1962 J. T. HAYWARD SUBMERGIBLE DRILLING BARGE WITH HULL PROTECTIVE DEVICES Filed Dec. 29, 1954 3 Sheets-Sheet 1 do/m 7. Hayward IN V EN TOR.

ATTORNEY Feb. 20, 1962 J. T. HAYWARD 3,021,680

SUBMERGIBLE DRILLING BARGE WITH HULL PROTECTIVE DEVICES Filed Dec. 29, 1954 3 Sheets-Sheet 2 I l l dob/7 7. Hag/w r INVENTOR.

A 7 ra e/v5 y Feb. 20, 1962 J. T. HAYWARD 3,021,680

SUBMERGIBLE DRILLING BARGE WITH HULL PROTECTIVE DEVICES Filed Dec. 29, 1954 3 Sheets-Sheet 3 a a 20 /4 a (/0/7/7 7. fiaywa/a/ INVENTOR.

ATTORNEY 3 021,680 SUBMERGIBLE DlRILLING BARGE WITH HULL PROTECTIVE DEVICES John T. Hayward, 122 Bayside Drive, Ciearwater, Fla. Filed Dec. 29, 1954, Ser. No. 478,335 2 Claims. (Cl. 61-465) In previouslyfilerl applications of John T. Hayward, 7

Serial No. 44,626, filed August 17, 1949, now Patent No. 2,540,878 of February 6, 1951, and Serial No. 65,475, filed December 15, 1948, now Patent No. 2,551,375 of May 1, 1951, there are disclosed submergible drilling foundations each comprising primarily a ilat bottomed barge hull which is adapted to be submerged completely beneath the water body to rest on the underlying land. The deck of the barge is provided with an open-work superstructure of a height sufficient to extend above the water surface when the barge is on bottom and a conventional drilling rig may be mounted on this superstructure, drilling normally being conducted therewith in the uusal manner through an open central slot or bay extending longitudinally of the barge hull from one end thereof. By means of such a submergible barge a firm foundation may be provided for the drilling rig which will not be seriously affected by high winds, waves and tides, which prevail in open ocean areas particularly, and the barge may be readily moved from location to location with relative ease and safety.

In many water locations, particularly in off-shore areas along the Gulf Coast of Texas and Louisiana, the ocean bottom will be covered by a layer of soft sand or silt. When a barge of the type described is sunk to such a bottom, sub-surface water movements, such as bottom currents and the like, may produce a scouring action about the edges and particularly about any relatively sharp corners of the barge hull resting on such a bottom. Such scouring action may wash the sand or silt from beneath portions of the barge bottom, thereby undercutting the bottom and resulting in undesirable and even dangerous tilting or shifting of the structure.

I have found that such undercutting action may be prevented or substantially obviated by providing about the periphery of the barge bottom, or along suitable portions thereof, a protective skirt or apron which may be rigidly connected to the hull to extend therefrom and become embedded in the underlying land bottom when the hull settles thereon toprovide a form of breakwater about the bottom edges of the hull.

Accordingly, it is one of the principal objects of the present invention to provide improvements in submergible drilling barges whereby to prevent undercutting of the barge when on bottom.

Those skirts or aprons, in accordance with this invention, which are adapted to be embedded in the land bottom also serve to prevent lateral movement of the submerged hull over the land bottom by their embedded engagement with the land bottom, or modifications thereof may be employed in a novel manner to apply suction which causes the barge hull to adhere more strongly to the land, or, alternatively, to break the barge loose from the bottom when necessary to re-float the structure.

The foregoing and other more specific objects and advantages of this invention will become apparent from fifizlfi fi Patented Feb. 20, 1962 the following detailed description when read in conjunction with the accompanying drawings which illustrate several useful embodiments in accordance with this invention.

In the drawing:

FIG. 1 is a profile view of a barge hull showing the hull submerged and landed on the bottom of a Water body and equipped with depending flange or skirt member adapted to be embedded in the land bottom;

FIG. 2 is a view looking upwardly toward the bottom of the barge shown in FIG. 1;

FIG. 3 is an end elevation of the left hand end of the barge hull;

FIG. 4 is an end elevation of the right hand end of the barge hull;

FIG. 5 is an enlarged fragmentary sectional view along line 55 of FIG. 2;

FIG. 6 is an enlarged fragmentary view taken in longitudinal section along line 6-6 of FIG. 2.;

FIG. 7 is a side elevational view of a submergible barge structure employing the hull construction of FIG. 1 and showing a superstructure including a drilling platform mounted on the barge hull; and

FIG. 8 is a view similar to FIG. -2 of a barge bottom showing another arrangement of the anchoring and protective flanges in accordance with this invention.

Referring first to FIGS. 1 to 4, inclusive, the barge hull B is of the generally rectangular shape having an upper deck it and a substantially flat bottom 11, side walls 12 and end walls 13. Each of the end walls is connected to bottom 11 by means of an angular rake portion 14. The hull is provided with an elongated slot 15 extending from top to bottom of the hull and along the longitudinal axis thereof from one end to the mid-ship portion of the hull, where it terminates in an inner end wall 16.

It will be understood that the hull will be fully watertight and compartmented in any conventional manner, and provided with means (not shown) conventionally employed for transferring ballast, such as sea water, to and from the several compartments in the usual manner to efbody 17 with its bottom resting on the sub-aqueous landsurface 18. A plurality of flange or skirt sections, indicated generally by the numerals 19, are rigidly connected to the bottom of the barge hull adjacent the periphery thereof and extend vertically downward therefrom for a short distance. These skirt sections are adapted to be embedded in land surface 18 when the barge hull has been submerged to settle thereon. Skirt sections 19 may be arranged at the corners of the barge hull and may extend along the sides and ends of-the hull as part-way along the sides of slot 15, all as illustrated particularly in FIG. 2. It will be understood that the skirt sections "may extend continuously entirely about the perimeter of the barge and along the slot walls, if desired, but ordinarily it is found that by placing the skirt sections about the corners of the hull and extending them only part-way along the sides and ends thereof, their function will be satisfactorily performed, as will be described hereinafter. An auxiliary rib, designated generally by the numeral 20, may be provided along the longitudinal axis of the hull extending beneath the hull between end wall 16 of the slot and the opposite end of the barge. Rib it? will normally be of about the same downwardly extending length as skirt sections 19 to provide balanced load support for the hull bottom when resting on land or in a dock.

Referring now to FIG. 5, a cross-sectional view of the skirt and rib sections is there illustrated, from which it will be seen that skirt section 19 is of hollow boxlike construction having a vertical outer side wall 21, which may be made generally flush with side wall 12 of the barge hull, a horizontal bottom wall 22 generally parallel to hull bottom 11, and an inner side Wall 23 which preferably slopes upwardly and outwardly, giving the skirt section a generally wedge shaped form for easier withdrawal from the land bottom. Hull bottom 11 forms the upper wall of the skirt section. The ends of skirt sections 19 are closed by means of end walls 24 (FIG. 2) and a plurality of longitudinally spaced stiffening plates 25 are installed transversely of the interiors of the skirt sections to reinforce the same, whereby the sections will have sufficient structural strength to support the load of the barge without danger of crushing. Each of the plates 25 is provided with an opening 26 therein whereby to provide open communication throughout the interior of the related skirt section. inner wall 23 of each of the skirt sections is also provided with a plurality of openings 27 to provide communication between the interior of the section and the space beneath the hull bottom adjacent to the skirt section.

Rib 20 is also of box-like construction, generally similar to that of skirt sections 19, except that both its side walls 28 and 2?, slope inwardly and downwardly toward a bottom wall 30, providing a generally wedge-shaped crosssectional configuration for rib 20, adapted both for easy embedding in, and withdrawl from, the underlying land and for strong support for the barge hull. A plurality of longitudinally spaced stiifening plates 31 are installed transversely across the interior of rib 20 for structural reinforcement and these plates also have openings 32 to provide open communication throughout the length of the rib, which is closed at its opposite end by means of plates 3333 (FIG. 6). Each of the side walls 28 and 29 is provided with a plurality of perforations 34 to provide communication between the interior of rib 2i) and the adjacent spaces beneath bottom 11. Openings 27 in skirt sections 19 and perforations 34 in rib 20 are employed in the performance of useful functions to be more fully described hereinafter.

The afore-described structure operates in the following manner: When barge B is submerged and its bottom settles onto land surface 18, skirt sections 19 will be forced into the land surface by the weight of the barge. If rib 24) is employed, it too will be similarly embedded in the land surface. When thus embedded, skirt sections 19 will form a shield about the perimeter of the bottom of the barge hull extending below the land-water inter-face on which the hull bottom rests. As a result, Water in movement over the land surface which may strike the walls of the barge hull will be deflected and will be unable to wash under the edges of the hull, and the danger of undercutting of the barge hull will be greatly obviated or entirely eliminated. Skirt sections extending about 18 inches below the bottom of the barge hull will generally be sufiicient for this purpose in most off-shore areas but may be longer or shorter as conditions dictate.

Since skirt sections 19 are rigidly connected to the hull bottom, they will also serve, when embedded in the land surface, as anchors which will assist materially in preventing lateral movement of the barge hull over the land surface under the impact of underwater currents or as a result of wave or wind pressure on the superstructure and will thereby contribute substantially to maintaining the hull immovable when resting on the subaqueous land,

The hollow skirt and rib constructions illustrated may be employed in a novel manner to increase the grip of the hull on the land bottom when landed thereon or, alternatively, to break the barge hull loose from the bottom preparatory to, or during re-floating of, the barge.

Primarily for convenience in illustration, the apparatus employed for these purposes will be shown in relation to rib 20 (FIG. 6), but it will be evident that similar or duplicate arrangements may be employed with skirt sections i9 or with other suitably located ribs for accomplishment of the desired purposes, as will be more fully set out hereinafter.

A pipe 56 connects the interior of rib 20 with the exterior of the barge hull through a conventional sea chest 51 which may be mounted, as illustrated, at the juncture of end wall 13 and rake portion 14, and communicates with the exterior of the barge hull through opening 51a in end wall 13. A valve 52 is interposed in pipe 50 to control the passage of water therethrough. A second pipe 53- connects the interior of rib 2.0 at the opposite end with the exterior of the barge hull through a conventional sea chest 54 whichmay be conveniently arranged, as illustrated, along inner end wall 16 of slot 15 at a suitable point intermediate the deck and bull bottom and communicates with the exterior of the barge hull through openings 54a in wall 16. A reversible pump 55, of any suitable and conventional design, is interposed in pipe 53 for the purposes of moving water between the interior of rib 2t) and the exterior of the barge hull.

When the barge hull has been submerged and landed on bottom 18, skirt sections 19 and rib 20 will, as previously described, be forced into the land bottom by the weight of the barge and will serve as anchoring devices to resist lateral movement of the hull over the land surface. Also in the case of soft bottoms, there will be some degree of adhesion between the bottom materials and the barge bottom. Nevertheless, it may be found highly desirable to augment these forces to assure complete immobility of the barge hull.

The above-described apparatus may be employed for accomplishing this purpose in the following manner: Pump 55 is driven in a direction to draw a stream of water from water body 17, in which the barge is submerged, through sea chest 51 and pipe 50 into the interior of rib 28 at one end and to discharge the water from the opposite end of the rib through pipe 53 and sea chest 54- back into the water body outside end wall 16. This circulation of water will create a reduced pressure in the closely confined space between the bottom surface of the barge hull and the adjacent land surface which will cause the barge bottom .to cling with increasing tightness to the land surface in contact therewith. The magnitude of the suction eifect may be regulated by suitably throttling valve 52. Any water and silt which may be drawn into rib 20 from beneath the barge hull will be continuously washed out of the rib by the stream of relatively clean Water which is. circulated through the rib by the pump. As circulation of water is continued, the suction eifect created thereby will extend over an increasing area beneath the barge hull, although in many cases the continued maintenance of only a relatively small reduced pressure area is all that may be required to hold the barge bull in place. As indicated previously, it will be evident that skirt sections 19 may be connected up: to pumping apparatus in substantially the same manner as described for rib 20 and suction produced through openings 27 in inner side walls 23 of the skirt sections, the resulting suction efiect thereby being caused to extend generally inwardly from the skirt sections beneath the bottom surface of thebarge hull. It will be understood that the desired suction effect may be created simultaneously through both the skirt sections 19 and rib 20, or through one or the other as may be found desirable in any particular case.

The suction creating apparatus may also be employed to break the barge loose from the land bottom when it is desired to re-float the barge. This may be accomplished simply by reversing the direction of flow of water through rib 20. In this instance pump 55 will take suction through sea chest 54 and pump the water through rib 21) toward pipe 50 and ultimate discharge through sea chest 51. By suitable throttling of valve 52, the water will be forced to discharge laterally out of rib 2% through openings 34 and between the bottom surface of the hull and the land surface, thereby freeing the hull bottom from the adhering land. Ordinarily this operation will be performed contemporaneously with the increase in buoyancy of the hull by removal of ballast so that the freeing of the hull may be efiected quickly and with minimum positive buoyancy applied to the hull. It will be evident that skirt sections 19 may be employed in like manner for freeing the hull from the land bottom.

It will be understood that one or more ribs 2% may be employed, if desired, and that such ribs may extend transversely as well as longitudinally of the hull bottom, and over various portions of the hull bottom intermediate the peripheral skirt portions.

FIG. 8 illustrates another arrangement for placement of the ribs on the hull bottom which is particularly advantageous for enhancing the anchoring function of the ribs. In this embodiment a plurality of pairs of ribs 19a are disposed in spaced apart relation distributed over the bottom 11a of a hull, each pair of ribs being disposed at an angle to an adjacent pair. The angular relationship of the ribs increases the anchoring function of the ribs, in that resistance to lateral movement is intensified irrespective of the direction of the forces urging movement of the barge. The particular angular relationship may obviously be varied widely and the placing of the ribs may be random rather than symmetrical or uniform. The ribs 19a may be employed with or without additional ribs along the hull periphery as shown in FIGS. 1 to 7.

Variation in the pressure in the ribs under different portions of the hull bottom may also be employed to correct any tendency of the bull to tilt. Also, various other alterations, changes and modifications may be made in the details of the illustrative embodiment 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:

1. A submergible barge, comprising, a hollow generally rectangular hull having a substantially flat bottom adapted to rest on a sub-aqueous land surface when the barge is submerged, open work superstructure comprising a plural ity of upstanding laterally spaced apart column members on said hull extending above the surface of the Water body in which the hull is submerged, a drilling platform supported by said column members above the surface of the water body, a longitudinal slot extending from one end of the hull to a mid-ship portion thereof, a plurality of flange elements rigidly connected to said bottom along the portions of its perimeter and adjoined at the corners thereof and extending downwardly therefrom into contact with said land surface in the path of water in movement about said corners, and an additional flange element extending along the center line of said bottom between the inner end of said slot and the opposite end of said hull.

2. A submergible barge, comprising a hollow generally rectangular hull having a substantially fiat bottom adapted to rest on a subaqueous land surface when the barge is submerged, a longitudinal slot extending from one end of the hull to a mid-ship portion thereof, a plurality of flange elements rigidly connected to said bottom along the portions of its perimeter and adjoined at the corners thereof and extending downwardly therefrom into contact with said land surface in the path of water in movement about said corners, and an additional flange element extending along the center line of said bottom between the inner end of said slot and the opposite end of said hull.

References Cited in the file or" this patent UNITED STATES PATENTS 891,966 Tromanhauser June 30, 1908 1,681,533 Giliasso Aug. 21, 1928 2,327,118 McKnight Aug. 17, 1943 2,661,600 Hopkins Dec. 8, 1953 2,699,042 Hayward Jan. 11, 1955

Images