US2842940A - Personnel landing for offshore platforms - Google Patents

Description

July 15, 1958 R. G. CAPPEL PERSONNEL LANDING FOR OFFSHORE PLATFORMS Filed sept. 22, 1955 2 Sheets-Sheet 1 /A//ENTOR# Po Y G- CFP/OEL,

HTToR/VEYS July 15, 1958 R. G. CAPPEL. 2,842,940

PERSONNEL LANDING FOR OFFSHORE PLATFORMS Filed Sept. 22, 1955 2 Sheets-Sheet 2 United States Patent() f PERSONNEL LANDING FOR OFFSHORE PLATFORMS Roy G. Cappel, Metairie, La., assignor to W. Horace Williams Company, Incorporated, New Orleans, La., a corporation of Delaware Application september 22, 195s, serial No. 535,823

10 claims. (c1. 61-48) The present invention relates generally to boat landing piers, and more particularly to a novel personnel landing for oifshore platforms by means of which' safe transference of personnel may be` made between thepier structure and a vessel moored alongside.

Briefly, the arrangement comprisesa generally con; ventional pier structure which4 includes a deck disposed well above the normal. water line. A landing net anchored to the deck extends generally downward almosttov the water level, being stretched between twov parallel hawsers which are secured to thedeck andwhich'extend down for securement also'to a collapsible,l shockabsorbing struts adapted to cushionfthe impact of'a vessel brought alongside the pier for mooring;

Various means for ascending froml the vessel'tothe deck of the pier are provided', including 'an opening through the landing net' for access to'a stairway. platform forming a permanent partof the pierstructure, a conventional caged ladder providedon'the outside 'ofithe landing net andfextending upwardly to the' deck, andthe landing net itself, which may be scaled like a ladder.'

Thus, it is an object of the present invention to' pro; vide a novel personnel landing which provides multiple means for safe transference of personnel" between ailoat-4 ing vessel and a xed pier.

lt is another object of the invention to provide a novel personnel Vlanding for offshore platforms 'which includes means for preventing damage eithertothe'pier structure or to the vessel during'- transference of passengers from one tothe other.

It is vanother object of the invention to provide novel personnel landing for offshore platformsl which includes novel means for absorbing the breasting force' of vessels moored beside the landing? The foregoing; along Withadditional objectsandadvantages, will be: apparent fromthe `followingl description of a preferred embodimentof the invention as depicted in the accompanying drawings;` in `which:

Figure l is affront'` elevational view=of-a"perso`nn`el landing foroffshore platforms conforming to the" presL entA invention;

Figure 2 is another Velevational'view takengenerally' along theline'2-2 of Figure l.;

Figure 3 is'a horizontal lview taken generally'from the positionof the line 3--3 of Figure l; v

Figure`4 is a fragmentary'view showing,`in sectiongtlie' structural arrangementof the .collapsible struts forming part of the landingestructure; 4and Figure 5 is a Yfragmentarysectional'view taken" gen# erally along the line 5-'5 of Figure'4 and illustrating a preferred mode ofA attachment' of theI 'collapsible' struts toqan element ofthe pier.

Referring toA the. drawings'.moreparticularly throughl mentionof the reference characters applied' thereto, the

numeral indicates `generallya personnel i landing for offshore platforms which is" constructed iri"accorda'nce" 2,842,940 Patented July 15, e

form or pier indicated generally by the numeral l2, which may be observed to comprise an elevated deck 14 supported in conventional manner upon joists 16 and stringers 18, the latter receiving vertical support from columns 20. It will be observed that the deck ,14, including the stringers 18, extends in cantilever fashion well beyond the line of columns 2t). The platform structli'remay further include tension rods 22 and compressionY struts 24, as illustrated, to provide a rigid integrated construction. Preferably, of course, the elevated deck 14 is provided with a safety railing 25 of generally conventional type.

In order that the drawings may be viewed in appropriate perspective, it may be mentioned that the deck 14 is'dep'ieted as being disposed at an elevation of some thirty feet above the surface of the water 30. Disposed at such an elevation, the platform 14'will normally be quite free from water surgesinduced by wind and tide. As a matter of'fa'ct, it isV assumed for the purpose of the present illustration thatthe normal water level at the time of boat landings will be approximately as illustrated in Figures l and 2. Thus, an auxiliary platform 32 constructed as' part of the pier structure 12 is illustrated as being disposed some ten feet above the surface 30 and being thus at a convenient height from which to embark or disembark from aV vessel moored alongside the -Kpier 12.

The auxiliary plaform 32, provided with its own railing34, is supported beneath the overhanging portion of the deck 14 by cantilever beams 33 secured to the main pier structure', and is connected to the upper platform 14 by` mea-ns of a conventional stairway 36. As best shown inFigure 3, the railing-34 extends around onlyV three sides of` the `platform 32, one end of the latter being open for passage4 of passengers to and from a oating vessel. l

Directing attention now to the landing device lil, a landing net 40 is anchored in any convenient manner at its upper vend to the deck or platform 14 `and descends downwardl-y` therefrom so as toV reach well below the auxiliary' platform 32, preferably to Vwithin approximately two feet ofthe water surface 30. The net4t`r is'stretched laterally between parallel hawsers 42, each faste-nedA to an individal structurall member, such as a Stringer 18, by r'rians ofappropriate rings 44 rmly secured to the particular elements 18. As clearly illustrated in'Figures l and 2, the hawsers 42 extend-downwardly from the rings 44 and are fastened, preferably'by aseries of halflii'tclie's, to' rings 46 mounted at the free ends of individual shock'strts V43. The above noted series of halfhitches is'clea'rly shown at 50vin Figure Y3. From this fasteningfto the rings 46, the hawsers 42 are extended further' downwardly for similar connection to ringsV 52 mounted at the ends of individual shock struts 54. Each hawse'r 42 is thenV extended horizontally for securement toV an upright column or pile 20 asbest'illustrated in Figure" 2.

As. is evident from the drawings, the shock strutsu48 and 54 are vdisposed below the auxiliary platform 32 so as to be in the area of vessel contact. There are illustrated an individual strut A48 and an individual strut 54 for each of the hawsers 42. Preferably, the arrangement is as clearly illustrated in Figures 2 and 3, wherein it will be observed that these struts are arrangedv in pairs with ay strut 48 and a strut 54 being pivotally secured to a common attachment plate 56 Welded orv otherwisev rigidly secured-to an upstanding column 2t).

Figure4 illustrates the shock struts 4S and 54: as being ofthe telescoping, spring-biased type which may be fabricated from-simple tubular dat plate stock as clearly shown in thisgure. Obviously, the'invention is not limited to-'the use of shock struts of the specifiedV type here illustrated, but may include the employment of struts variously designed to provide an equivalent shock absorbing function.

A preferred type of pivotal securement of the struts 48 and 54 to the mounting plate 56 is illustrated in Figures 4 and 5, from which it will be observed that parallel extensions 58 at one end of the strut 48 are arrangedto embrace the plate 56, and that parallel extensions 60 at the end of the strut 54 are arranged, in turn,to embrace the extensions 58. These several elements are'then pinned together by means of a pivot pin 62 retained by a cotter pin 64.

For added rigidity of the shock strut assembly, the two struts 48 are cross-braced in a well-understood manner by means of bracing elements S5 as shown in Figure 3. Similarly, the struts 54 are cross-braced by means of bracing elements 66 as shown in Figure l. As also shown in these two figures, a hawser 68 is strung horizontally between the two rings 46 at the free ends of the struts 48, and a hawser 70 is strung between the rings 52 at the ends of the struts 54. Clearly, these hawsers 68 and 70 serve to provide added backing or support for the landing net 40 in the area of vessel contact.

Directing attention once more to the landing net 40, a rectangular opening 72 is provided therein at a point opposite the open end of the axuiliary platform 32. This opening 72, clearly illustrated in Figure l, enables passengers to move directly from a vessel moored on one side of the net 40 to the auxiliary platform 32 disposed on the other side thereof.

A fixed ladder 74 provided with a conventional cage 76 is secured in any appropriate manner to the structure of the platform 12 so as to be disposed on the outside of the landing net 40. This arrangement is also illustrated in Figure l, the ligure showing the ladder extending from the general level of the opening 72 upwardly to the main deck 14. The aforementioned railing 26 surmounting the deck 14 is interrupted, not only at the point where the ladder 74 reaches the deck 14, but all the way across the top of the landing net 40. The space intervening between the ends of the interrupted railing 26 is provided with spaced assist posts 78 for a purpose to be described.

The manner of use of the landing device is generally obvious from the foregoing description. Normally, the vessel will be brought up on the outside of the landing net 40, the breasting force being absorbed by the lower end of the net 40 supported by the hawsers 42, 68 and 70, and by the aforementioned arrangement of shock struts 48 and 54. The net 40, itself, is required to absorb but very little of the breasting force of the vessel, the main force being taken by the hawsers and transferred to the struts 48 and 54. The securement of the hawsers to the rings 46 and 52 by means of a series of halfhitches provides a mass of rope at these points which serves as a bumper to minimize the likelihood of damage to the vessel at these points of contact. y

Once the vessel is brought into landing position on the outside of the landing net 40, the passengers may reach the upper deck 14 by any of three avenues. They may use the stairway 36 by stepping through the opening 72 in the net 40 onto the platform 32 and then ascending the stairway 36; they may use the protected ladderway 74; or they may scale the landing net 40, itself, assisting themselves onto the upper deck 14 by means of the assist posts 78. The horizontal elements 80 of the net 40, or at least those above the opening 72, may well comprise metal rods or equivalent construction to facilitate climblng.

The above mentioned alternative modes for transference of passengers to or from a vessel moored alongside the landing device 10 provides a exiblity of use which enables passengers to be transferred under many circumstances which would prove difficult, dangerous or irnpossible with landing devices heretofore used. For example, during periods of high water or rough water,

- when it is difficult or impossible to step from the vessel through the opening 72 to the platform 32, the alternative methods of scaling either the ladder 74 or the net 40 are always available.

Clearly, there has been described a personnel landing for offshore platforms which fulfills the objects and advantages sought therefor.

It is to be understood that the foregoing description and the accompanying drawings have been given only by way of illustration and example. lt is further to be understood that changes in the form of the elements, rearrangement of parts, or the substitution of equivalent elements, all of which will be obvious to those skilled in the pertinent art, are considered to be within the scope of the invention, which is limited only by the claims which follow.

What is claimed is:

l. An offshore landing comprising, in combination, a pier structure including a main deck disposed at an elevation substantially above normal water level, said pier structure further including a pair of vertical supports disposed laterally inwardly of one edge of said main deck, flexible means including net means secured adjacent said edge and extending generally downwardly therefrom in spaced relation to said vertical supports, and yieldable struts disposed between said downwardly extending means and said supports for absorbing the breasting force of vessels brought into landing engagement with the lower portion of the downwardly extending means.

2. The combination of claim 1, wherein the downwardly extending means includes spaced hawsers, there being at least one yieldable strut for each hawser, and wherein each hawser and strut combination is secured to a respective vertical support.

3. The combination of claim 2, wherein the pier structure includes an auxiliary platform disposed at an elevation intermediate the normal water level and the main deck, said platform having an outer edge disposed approximately vertically below the edge of the main deck so that the downwardly extending tiexible net means may pass the auxiliary platform outwardly of said outer edge, said yieldable struts being disposed below said auxiliary platform and being of sutcient length to prevent a vessel or the like from engaging the latter, an opening in said net means opposite said platform for transference of passengers therethrough, and means for ascending from the auxiliary platform to the main deck.

4. The combination of claim 3, wherein a caged ladder is provided on the outer side of the net, said ladder extending upwardly to the main deck of the pier structure for providing access thereto from a level above the auxiliary platform.

5. A device for facilitating transference of passengers from a vessel or the like to an offshore pier having at least a pair of horizontally spaced vertical supports and an overhanging main deck, said device comprising, in combination, a landing net having an upper end secured adjacent an outer edge of said overhanging deck and extending downwardly therefrom to within a short distance of a normal water surface level, a pair of horizontally spaced hawsers secured to said pier adjacent said deck and extending along opposite side edges of the net for at least the full length of the latter and means including horizontally spaced strut means disposed between the lower portion of said net including the hawsers associated therewith and said pair of spaced supports for approaching the same, the lower portions of said hawsers being extended inwardly for securement to respective pier supports.

7. The combination of claim 6, wherein each hawser is connected to a respective pair of struts including a horizontally disposed strut and a strut disposed at an inclination to the horizontal, said pair of struts having a common pivotal connection to an individual vertical pier support, said inclined strut being longer than said horizontal strut and being disposed below the latter.

8. The combination of claim 7, wherein the horizontal struts connected to dilerent hawsers are cross-braced for added rigidity, wherein the inclined struts connected to different hawsers are similarly interconnected, and wherein auxiliary hawsers are secured between the free ends of each pair of interconnected struts to provide added lateral support for the lower portion of the net.

9. A landing for use with an otshore pier having an elevated deck supported by vertical columns disposed sub stantially inwardly of one edge of said deck and having an auxiliary stair connected platform located below that portion of the deck that extends outwardly beyond said vertical columns, said landing comprising, in combination, means including a landing net extending from the outer edge of the edck downwardly past the auxiliary platform to within a short distance of a normal water level, said net having an opening therethrough adjacent said platform to enable personnel to pass from a vessel or the like on one side of the net to the platform on the other side,

and resilient shock absorbing means disposed at a level below that of the auxiliary platform and extending between said vertical columns and that portion of the landing net which hangs below the platform.

l0. The landing of claim 9 wherein the means extending downwardly from the edge of the elevated deck includes a hawser along each side of the net, said hawsers being secured at their upper ends to the deck structure,

intermediate their ends to the outer ends of the shock absorbing means, and at their lower ends to the vertical columns.

References Cited in the tiley of this patent l UNITED STATES PATENTS OTHER REFERENCES Never Were Seconds' More Precious, The American Chain Ladder Co. lnc., received Aug.` 18, 1943, pp. 2, 3, 6, 7, 8 and 16.

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