US2637172A

US2637172A - Offshore drilling platform

Info

Publication number: US2637172A
Application number: US37599A
Authority: US
Inventors: Kenneth C Howard
Original assignee: Richardson & Bass
Current assignee: Richardson & Bass
Priority date: 1948-07-08
Filing date: 1948-07-08
Publication date: 1953-05-05
Anticipated expiration: 1970-05-05

Description

May 5, 1953 K. c. HOWARD OFFSHORE DRILLING PLATFORM 2 SHEETS-SHEET l Filed July 8, 1948 INVENTOR K, c. Hon/ARD Blf/WM May 5, 1953 K. c. HOWARD OFFSHORE DRILLING PLATFORM 2 SHEETS--SHEET 2 Filed July 8, 1948 K C. HOM/ARD Y IN VENTOR BWM ATTORNEY Patented May 5, 1953 OFFSHORE DRILLING PLATFORM Kenneth C. Howard, Fort Worth, Tex., assignor to Richardson & Bass, Fort Worth, Tex., a. corporation of Texas Application July 8, 1948, Serial N o. 37,599

(Cl. (i1-46) Claims.

This invention relates to oil well drilling apparatus, and has reference to an oli-shore drilling platform.

An object of the invention is to provide a construction whereby oiT-shore drilling platforms may Ibe imbedded and secured in subaquatic sand, silt, or the like, so as to provide a lirm foundation for the said platform.` y VA` `Another object of the invention is to provide a construction for off-shore drilling platforms which may be made into relatively large sections and floated by their own buoyancy to the desired drilling location.

l A -further object of the invention is to provid-e iioatable sections for an off-shore drilling platform which may be vertically placed, prior to imbedding the same inthe subaquatic soil, withoutusing heavy equipment such as cranes or otherheavymachines.

Another object of the inventio-n is to provide anv off-shore drilling platform l which, when assembled, is unusuallystrong, and one which is capable of resisting wave action and strong water currents frequently encountered in oli-shore drilling. Y

'A further object of the invention is to provide an 'off-shore drilling platorm which may be easily salvaged when required.

AV particularobject of the invention is to provide -afloatable large section or subossembly for an off-shore drilling platform having floats at lthelower end thereof, whereby water or air rcay Abe introduced into the same for either sinking or raising the same. v

A further object of the invention is to provide floats 0r pontoons at the lower ends of sections of oli-shore drilling platforms, and which pontoons or floats' may be imbedded in the subaquatic soil so as to provide suicientsoil engaging area for supporting the drilling platform `when the latterkis imbedded at the drilling location. In accordance with theY present invention this is accomplished by making each pontoon `relatively long in comparison with its cross sectional diameter, so that the ponton-ns may be sunk deeply into the soil or silt, thusenabling them to resist the wavel orcurrent action, which action if applied to relatively short but broad based pontoons wouldpsoon `erode the soil from beneath the pontoons, Vrendering them ineiiective as bases or foundationsiorthe supporting columns, .and permitting shifting oi the platform` carried by the columns. Thearea of contact with like.

,.I'lfiese and other 'ob cts oitlie inventionwill v ,become apparentV from' e following description o f the accompanying drawingslwherein: `Fgure ,1.'is an"elevati`onal"`view of .a drilling platform embodying"tneffeatufes' of the present invention, and showing the same imbedded in the subaquatic soil of an off-shore drilling location.

Figure 2 is an enlarged elevational and sectional view of one of the pontoons or oats secured to the lower end of a tubular support.

Figure 3 is a side elevational View of one of the sections illustrated in Figure 1 and showing the same having its end supported on a barge for oating the said section to the drilling location.

Figure 4 is a transverse sectional view of one of the pontoons or floats illustrated in Figure l. l Figure 5 is a broken elevational View of a modied form of pontoon, first illustrated in Figure 1, but showing an annular nozzle means in addition thereto for washing soil upwardly around the said pontoon when the latter is being implaced in the subterranean soil.

Figure 6 is a perspective view of an arrangement for securing the sections of the drilling platform together at their Upcer ends.

`The form of the invention illustrated in Figure 1 includes units or sections I including a multiple of tubular supports or columns 2. The broad side of a section l is illustrated in Figure 1f, whereas the width of a section is illustrated in Figure 2. The illustrated vrelation of width to side is merelv exemplary and not to be construed as a limitation. The tubular supports 2 are arranged in s^aced parallel relation with respect to each other and are secured by braces 3 which are welded in place. The lower end of `each tubular support 2 is encased by a closed longitudinal tubular iioat or pontoon 4 having round ends, as shown in detail in Figure 2. Within the length oi each tubular support 2 there is a water washing pipe 5 which opens outwardly of the bottom center oi the elongated float 4. As will be seen, the purpose of the water nine 5 is towash away the subaouatic soil for sinking the pontoon into place. Another small pipe or air line 6 is provided through the length of each tubular support 2 and has its lower end disposed through the said support and into the upper end of the iloat 4. Similarly, another small pipe or ballast line l extends downwardly through the tubular support 2 to where it opens into the lower end of the pontoon or oat Li.

Each assembled section may be floated to the drilling location by securing the upper end of the same-to ar barge 9,01 other vessel. When the barge 9 is above the desired'location, the air in the floats 4 is evacuated th-rough the small pipe 6,-and Vwater is introduced into the said floats by means of the water supply pipes 1. The floats then sink to the surface of the subaquatic soil and the section I assumes a vertical posi.- tion sincev the upper end of the section is sup.- ported by the barge 9. It is to be understood thatthe depth of the water at the drilling location is known, and that the height or length of each section l is made accordingly, and so 4that the upper end of the said section will project above the surface of the water. After the section I has assumed the described vertical position, water is forced under pressure downwardly through the wash line 5 where it disturbs and washes away the silt or soil l beneath the floats 4. By reason of the weight of the assembly I, and the described washing action, the floats 4 sink into the soil or silt Il). It is preferred that the floats 4 be completely submerged in the soil or silt I0 so as to resist the wave and current action on the supports 2.

Another section or assembly I is then floated to location and lowered adjacent to the previously installed section I in the manner previously described. After a sufcient number of sections have been thus placed, the upper ends of each section are secured 'by suitable means such as the illustrated diagonal cross-ties I I which are secured to the ends of the upper horizontal plates 8 by means of bolts I2. Each cross-tie Il may be secured one to the other where they cross by other bolts I3. When the assembly of sections I is completed, a suitable platform I4 is secured on the upper ends thereof and a well derrick I5, indicated by dotted lines in Figure 1 is positioned on the said platform. The well casing I6 beneath the derrick I is also indicated by means of dotted lines.

As shown in Figures l through 4, the described floats 4 may be provided with radially extending longitudinal fins I 'I for increasing the area in contact with the silt I0 after the latter has settled around the said floats.

The entire described drilling platform may be completely salvaged by removing the platform I4, the cross-ties II, and by lifting the separate sections I by means of evacuating water from the floats 4 and introducing air therein to again make the sections floatable. In many cases it may be desirable to flush the silt at the lower end of each float 4 'by means of the water supply line 5, and thus disturb the silt and release the said float. The sections are then floated to land by means of the barges 9 in the manner previously described.

The float 4 illustrated in Figure 5 is similar to the ones previously described but differs in that a convex air chamber I8 is positioned over the lower end of the said float, and which chamber is provided with an inwardly directed flange I 9 around its periphery, and which flange is perpendicular to the curved lower surface of the said float. A series of upwardly and outwardly directed orifices 20 are formed in the flange I9 and communicate with an opening 2| in the wash pipe 5. The last described arrangement of orifices 20 is in addition to the washing action at the lower end of the said wash pipe. The last described arrangement is for the purpose of augmenting the washing action and moving the silt upwardly along the surface of the float 4.

The described form of the invention is not restrictive, but may be made in many ways Within the scope of the appended claims.

What is claimed is:

1. A supporting unit for an off-shore drilling platform comprising a rigid tubular support and a closed streamlined float connected to the tubular support at one end thereof, said unit being adapted to be floated to a place of' assembly in a horizontal position, the float lowered beneath the surface of the water and embedded in the subaquatic surface While a -portion of the rigid tubular support projects upwardly beyond the surface of the water to permit attachment of the drilling platform, said float being of tubular form rounded at its lower end and surrounding the lower portion of the support, jetting means comprising a pipe extending downwardly through the tubular support and opening through the bottom of the float for supplying jetting fluid beneath the float for removing mud or silt to facilitate embedding and removing the float, means for selectively supplying and removing air to and from the interior -of the float comprising a second pipe separate from the jetting pipe and extending downwardly through the tubular support and communicating with the upper portion of the interior of the float, and means comprising a third pipe extending through the tubular support and communicating with the interior of the float at the lower portion thereof for selectively supplying to and removing from the float ballast fluid, permitting the float to settle to the bottom or to be floated to the surface as desired.

2. A supporting unit as set forth in claim 1, wherein a convex chamber is positioned beneath the lower end of the float.

3. A supporting unit as set forth in claim 2, wherein the convex chamber is provided with an inwardly directed flange around its periphery perpendicular to the curved surface of the float. and a plurality of outwardly directed orifices formed in the flange and communicating with the outlet opening of the jetting pipe.

4. A submersible and retrievable supporting element for an off-short drilling platform, comprising a rigid column having a vertically elongated float member rigidly secured at the lower portion thereof, said supporting element being equipped with conduit means extending downwardly along the length of the column for selectively supplying and removing fluent ballasting material to and from the float member to permit lowering or raising the same, and separate conduit means also extending through the float member for supplying under pressure jetting fluid beneath the float member to erode the soil from beneath said float and permit the same to settle deeply in the soil when the oat member is being submerged or to facilitate removal of the float member from the soil when the float member is to be removed, said float member being of substantially greater length than its transverse dimension, permitting the float to be submerged within the subterranean soil by the action of the jetting fluid sufficiently to resist the wave and current action on the supports.

5. A supporting element for an off-short drilling platform as dened in claim 4, wherein the float is provided with a longitudinally extending n for increasing the area of contact with the subterranean soil after the float has been embedded therein.

KENNETH C. HOWARD.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 947,237 Hindes Jan. 25, 1910 1,718,006 Reno June 18, 1929 1,892,125 Armstrong Dec. 27, 1932 2,210,408 Henry Aug. 6, 1940 2,327,118 McKnight Aug. 17, 1943 2,373,319 Long Apr. 10, 1945 2,422,168 Kirby June 10, 1947 2,539,695 Moon v, Jan. 30, 1951