US2948120A - Supporting leg assembly for marine platform - Google Patents

Description

Aug. 9, 1960 G. E. SUDEROW SUPPORTING LEG ASSEMBLY FOR MARINE PLATFORM 3 Sheets-Sheet 1 Filed Sept. 23, 1956 Georg e E.S,udezp,u,

WMM A'I'II'ORNEYS 2,948,120 SUPPORTING LEG ASSEMBLY FOR MARINE PLATFORM Filed Sept. 28, 1956 Aug. 9, 1960 G. E. SUDEROW 3 Sheets-Sheet 2 IN VENTOR I Ge 07:92 E filderou MM| MQMW ATTORNEYS.

Aug. 9, 1960 5. E. SUDEROW SUPPORTING LEG ASSEMBLY FOR MARINE PLATFORM 3 Sheets-Sheet 3 INVENTOR:

United.- States-.- Patent Q SUPPDRIING'IEGASSEMBLYFORMAIRINE r PLATFORM GeorgerE. .f Snderow; New. York, -.N.Y., assignor .to De Long Corporation, New York, N.Y., a corporation of Delaware FiledSept;28, 1956; Ser;N6;J612;815 a claimsancl. 1151;216:515

This. invention relates .to convertible marine platforms and morep-articularly: to supportingleg assemblies for such platforms having jacking means for rela-tively ma nipulating. theasupporting "legiassemblies-and .platforms so that the-latter can-be convertedafroma floating plata form .to .anclevated platform supported by the marine? botbom above the water level and. .vice versa.

The present invention is particularlyluseful in the marine installation-system such as disclosed-in .the Pointer application Serial No. 283,567, fileda April 22, .1952, and

now? Patent Number 2,775,869. In general, this'system embodies the utilization of a floating platform which may bettransported to'any suitablemarine site, as by tugs or it the. .like,-and-which is provided. with a .series of guide it meansfor receiving a corresponding .series -.of elongated supporting-legs which are :utilized whenithe floatingbarge has -been transported to the: marine.-; site to support the floatingfi barge ,7 from the marine bottom in am elevated. 1 position :above the-water level-s -..Ther system disclosed in the afores'aid Pointer tapplicationa illustrates v the use: of

tubularone-piece?supporting legswhich are initially slowered through thelplatform guidemeans bymeans-of tpneumatically: operated: jacking-I mechanisms untii the- .lower ends thereof are embeddedsin the marine .bottom, 7-. SubscqneritlY, :thejacking-mechanismsare operable to raise thezplatform ton thesupporting-Je'gs =10 -.a suitable height a above thei-water level? With ether platform vthus, ".sup--. ported; the same maylbetutilized-fona variety of purposes For example, permanent docks and piers have been.con-- structedutilizingithis: system and it is also valuable in off- .shoredrilling .operat-ionswhere theplatform isto: be used temporarily; -In.-the1latter ease, -the jacking. mechanisms are'roprable'to permit the platform to be lowered on the.-

supportingaleg'siuntil the same is again =fioating-on the surfac ofttlievwater and them-to subsequently raise the w supportingrlegsrclear ofathe .marinet bottom and. to a transportingposition i on. the platforms In most-installations iitis ofimportance-to provide an elevated :platform which has a substantially unobstructed upper-dec'k surfacea Ducto the uncertainty andthe unevenness of the rmarin'ewbottom; -it is usually the case when tlcalin'giwithpne-piece supporting legs that the-upp er ends -t herofiwill project :above thevupper deck surface of th e" platform whenrthewlatter-hasireached its: operativc elevated 'JpOSitiOm'F In permanent 1 installations-tithe t suppqpting leg's can be welded or otherwise permanently securedtoZ the platform-and the upperfends cut oif, but. this' is notpractical'in temporary installations." '.Moreoveizfthisiprocedure is time "c nsuming and cost1y;

Cdii's'equentlwin a later application: Sefi-al Non-584g962,

continuation of application :Serial 1N0.""502,313,.Pfiled April. l9,'..'1'955,*and now abandoned; it wasproposedto construct the supporting legs of. telescopic sections so as to insurethatstherewould be no obstructing upper support? ing leg ends extending above itheplatform deckwhenthe same is elevated to its operative position. Moreover,

ice.

thissectional construction renders the legs easier to handle and affords more flexibility in operation.

Briefly,.the telescopic supporting leg asembly disclosed in the above-mentioned Suderow application includes a pluralityof telescoping sections having jacking mechanisms between adjacent sections with the outer section mounted for vertical movement with respect to the platformby a jacking mchanism carried by the platform.

Thejackingmechanisms disclosed by the platform. The. jacking mechanisms disclosed are of the pin type embody ing horizontally 'slidable pins engageable in a series of longitudinally spaced apertures formed in the supporting leg sections. While this type of jacking mechanism provides a positive mechanical restraint a'gainstmovement. of the. -sections,due to the fact that the pins must en-x gage apertures which are spaced apart a fixed distance, there areinherent disadvantages in achieving minute incremental adjustments between. the sections themselves and thefsections with respect to the platform.

type described having improved means for efiecting relative longitudinal movement between the sections which readily ,enables..minute incremental movements to be made.

Another object of the present invention is the provision of a supporting leg assembly of the type described'having improved means for effecting longitudinal movement in either direction thereof with respect to a floating'barge' or platform even in minute increments.

Still another object of the present invention is the pro= vision of a' telescopic supporting leg assembly having im-" proved means for selectively effecting or restraining'rela tive longitudinal movementof the assembly with'respect to a floating barge or platform and improved means for" selectively'eifecting or restraining relativelongitudinal'i T movement between the scctionsof the assembly itself.

A still further object of thepresent invention is the pro vision ofa supporting leg assembly of thetype described which ais "simple in construction, easy ,to operate and economical to manufacture and maintain;

These and othenobjectswill become more apparent. during theacourse' of the following detailed description andappended claims.

embodiment is shown.

In the drawings :1

Figure. 1 is a vertical sectionalview showing a float ing} barge for platform having a telescopic. supporting f leg assembly embodyingthe principles of thepresent invention-applied thereto and illustrating the same. in

a, collapsed transport position;

Figure 2a. is aview similar to Figure'l illustrating the upper portion of the assembly in its extended operative position;

Figure 2b is a view similar to Figure 2a showing the? lower portion of the assembly; and

Figure 3 is a cross-sectional view taken alongithe line 33 of Figure 1.

Referring now more particularly I0 the drawings,"

tem, the floating platform 12' may be provided with a Accordingly, it is an object of the present invention to provide a telescopic supporting leg assembly of the e The invention may best be understood with reference to theaccompanying drawings whereinan illustrative series of telescopic supporting leg assemblies which may be cooperatively operated so as to effect the various movements essential to the marine construction. In the drawings, only a portion of the floating platform is illustrated showing a single guide means 14 in the form of a vertical opening arranged to receive the single assembly 10.

The assembly 10 comprises a plurality of telescopically-arranged sections, generally indicated at 16, 18, and 20. It will be understood that any number of sections may be utilized, the three shown in the drawings being merely illustrative. The section 16 constitutes an outer section; the section 20, an inner section; and the section 18, an intermediate section. The exterior surface of outer section 16 is provided with a pair of diametrically opposed elongated racks 22 which extend longitudinally substantially throughout the entire length thereof. Each of the elongated racks is engaged by a worm gear 24 suitably journaled on the platform 12 for rotation about a vertical axis. Each worm 24 extends through the adjacent opening 14 into engagement with the cooperating rack 22 so as to effect or restrain relative longitudinal movement of the outer section with respect to the platform. Any suitable actuating means may be provided for driving each worm 24 and, as shown, a motor 26 is provided which turns a secondary worm gear 28 through a suitable reversing transmission 30. Each secondary worm gear drives a pinion 32 fixed with respect to the associated worm 24 so that rotation of the former will effect rotation of the latter. It will be understood that the motors 26 may be controlled in unison so that each worm 24 will be operated simultaneously so as to effect the vertical movement of the outer section.

A secondpair of elongated racks 34 are mounted on the interior surface of the outer section in diametrically opposed relation and extend substantially throughout the entire length of the same. The upper end of the intermediate section has a pair of cooperating worms 36 mounted thereon for rotation about vertical axes. Each worm 36 is also provided with an actuating means including, as before, a reversible motor unit 38 driving a secondary worm gear 40 which in turn meshes with a pinion 42 mounted for movement with worm 36.-

The intermediate section 18 is also provided with a pair of elongated racks 44 fixed to the interior surface of the section in diametrically opposed relation and extending substantially throughout the length of the same. Preferably, the racks 44 are displaced angularly with respect to the pair of worms 36 and, as shown, this angular displacement is approximately 90 degrees. The upper end of the inner section has a pair of worms 46 mounted thereon for rotation about vertical axes and for cooperation with respective racks 44. As before, the worms 46 are provided with actuating means preferably in the form of a reversible motor unit 48 arranged to drive a secondary worm 50 which meshes with a pinion 52 mounted for rotation with the worm 46.

As best shown in Figure 3, the racks 22, 34 and 44 are formed with a concavely shaped exterior surface which engages a substantial portion .of the periphery of the associated worm so as to prevent relative rotation between adjacent sections and between the outer section and the platform.

At the lower end of the inner section 20 there is mounted a telescopic footing assembly, generally indicated at 54. The assembly 54 preferably is constructed in accordance with the disclosure of copending application Serial No. 469,092, filed November 16, 1954, by George E. Suderow and now Patent No. 2,909,901. Briefly, the assembly 54 includes a plurality of inverted substantially cup-shaped members 56, 58, 60 and 62 of progressively diminishing diameter such that the same can be nested together in'telescopic relation. Each of the members 56, 58, 60 and 62 includes a central aperture through which the lower portion of the inner section 20 extends. The lowermost extremity of the inner section is provided with a radially outwardly extending peripheral flange 64 which is adapted to engage the lower inner periphery of the inner member 62. The inner member 62 is provided with an upper radially outwardly extending peripheral flange 66 which is adapted to engage a lower radially inwardly extending flange 68 on the adjacent member 60 so as to limit the relative movement between the two. Member 60 also includes an upper radially outwardly extending peripheral flange 70 which is adapted to engage a lower radially inwardly extending flange 72 on the member 58 so as to limit relative movement between the two. In a like manner, the member 58 includes an upper radially outwardly extending peripheral flange 74 which is adapted to engage a radially inwardly extending flange 76 on the lower end of the member 56 so as to limit relative movement between the two.

In utilizing the present invention in the system of the aforesaid Pointer application, it will be understood that a series of telescopic supporting leg assemblies will be utilized on a platform and simultaneously moved as described in that application. With the above in mind, operation of a single assembly of the present invention will now be described. After the floating platform or barge has been transported to a suitable marine site with the telescopic supporting leg assembly in its retracted leg position, as illustrated in Figure l, the motors 26, 38 and 48 are actuated so as to set the corresponding worms 24, 36 and 46 into rotation. The precise order in which actuation of the motors 26, 38, and 48 is performed is of no particular significance, it being understood that they may be actuated simultaneously or alternately. The important consideration in actuating the various motors is to insure that when the supporting leg assembly has finally reached its operative position wherein the inner section is firmly embedded in the marine bottom and the outer section is carrying the platform at a suitable height above the water level, the upper end of the outer section will be maintained flush with the upper deck surface of the platform. It is this arrangement which makes the telescopic arrangement more advantageous than a one-piece supporting leg, such as described in the aforesaid Pointer application. Consequently, it will be readily appreciated that by suitably actuating one or more of the motors controlling the various worms, the above condition can be readily achieved.

It has been found preferable to actuate the inner member initially by operating the motor units 48, thus turning the worms 46. It will be understood that rotary movement of the worms 46 in one direction causes the inner section to move vertically downwardly with respect to the intermediate section due to the cooperation of the worms with the elongated racks 44. Of particular significance in this regard is that the worm and rack arrangement is of the self-locking type so that relative longitudinal movement between the inner section and intermediate section is restrained when motor units 48 are not in operation. Of course, this same restraining effect is present as between the worms 36 and racks 34 and the worms 24 and racks 22. This arrangement affords a positive lock between any two adjacent sections and at the same time permits minute incremental movement therebetween.

After the inner section has been lowered to its limiting extent within the intermediate section, the motors 38 of the latter are actuated to lower the intermediate section together with the inner section relative to the outer section. Here again, the operation of the worms on the racks 34 effects a highly advantageous movement. Generally, the marine bottom will be engaged during the lower movement of the intermediate and inner sections with respect to the outer section and this engagement continues until the bottom of the inner section and the telescopic footing assembly are firmly embedded in the marine bottom.

The footing assembly operates in the same manner as the aforesaid Suderow application Serial No. 469,092 and now Patent No. 2,909,901 and serves to aiford greater support for the assembly from the marine bottom when the latter is embedded therein.

With the telescopic supporting le assembly embedded in the marine bottom, the motors are then actuated to rota te the worms 24 in engagement with the exterior legs 22 of the outer section. This operation effects at raising of the floating platform relative to the supporting leg assembly. When the platform has assumed a desired height above the water level, the upper end of the outer end section should 'be flush with the deck surface of the platform if suitable precautions have been previously undertaken. If this flush relationship does not exist, it is a simple matter to operate the motor units 38 of the intermediate section in conjunction with the motor units 26 of the platform so as to bring the upper end of the outer section into flush relation with the outer deck of the platform.

If the platform is used as a temporary installation, the above procedure may be reversed so as to again render the platform floating and permit the same to be transported to another site. It will be understood that the platform is first lowered on the supporting leg by reversing the direction of operation of the motor units 26 and 38 until the platform is again floating on the surface of the water. Next, the motor units are continued in reverse operation until the supporting leg is pulled free of the marine body utilizing the buoyant platform to resist the reaction force necessary to effect the freeing of the leg. Finally, the supporting leg is elevated to its transport position, shown in Figure l, and the platform is ready for transport to a new site.

It can thus be seen that there is provided a telescopic supporting leg assembly which is particularly useful in a system such as described in the aforesaid Pointer application. The telescopic arrangement of the supporting leg serves to insure that for any given height to which the platform is ultimately raised, the upper end of the outer section may be brought into flush relation .to the deck surface thereof. By providing a worm gear and rack arrangement for effecting relative movement between the platform and the assembly, as well as the relative longitudinal movement of the sections of the assembly itself, a positive locking by mechanical action is provided which insures that there will be no accidental relative movement as the result of power failure. Moreover, the arrangement is susceptible to minute incremental adjustments thus rendering the entire operation more flexible.

It thus will be seen that the objects of this invention have been fully and efiectively accomplished. It will be realized, however, that the foregoing specific embodiment has been shown and described only for the purpose of illustrating the principles of this invention and is subject to extensive change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.

I claim:

1. In apparatus of the type described, the combination comprising: a platform, a vertically extending telescopic supporting leg including an outer section, an intermediate section, and an inner section, guide means on said platform mounting said outer section for substantially vertical movement in either direction relative to said platform, first vertically extending rack means fixed to the outer periphery of said outer section, first worm gear means carried by said platformoperatively engaging said first rack means, first power means for driving said first worm gear means in either direction, second vertically extending rack means fixed to the inner periphery of said outer section, second worm gear means carried by the upper end of said intermediate section operatively engaging said second rack means, second power means for driving said second worm gear means in either direction, third vertically extending rack means fixed to the outer periphery of said intermediate section, third worm gear means carried by the upper end of said inner section operatively engaging said third rack means and third power means for driving said third worm gear means in either direction.

2. The combination as defined in claim 1 wherein said first, second and third rack means each comprises a pair of diametrically opposed elongated racks and wherein said first, second and third worm gear means each comprises a pair of worm gears operatively engaging an associated rack.

3. The combination as defined in claim 2 wherein said first, second and third power means each comprises a pair of pinion gears fixed with respect to the associated pair of worm gears and a pair of power transmission Worm gears drivingly connected to said pinions.

Payson Oct. 22, 1935 Bulkley et a1 Jan. 19, 1943

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