Boom As A Barrier For Oil Slicks And The Like On The Surface Of Water

Abstract

The boom comprises a number of non-pneumatic floats arranged in spaced alignment and a flexible web wrapped completely around the floats and bridging the spaces therebetween. The side sections of the web beyond the floats are secured together face to face and weights are attached to the web near the marginal edge of these side sections to form a downwardly extending weighted ballasting fin. The fin forms a hinge connection near the floats to permit the fin to swing about the hinge axis without transmitting its movements to the floats.

Description

The present invention relates to a boom designed to serve as a barrier around or along an area of water to confine any oil-slicks or any other water surface pollutants against spreading.

Objects of the present invention are to provide a new and improved boom for the purpose described, which is lightweight and comparatively inexpensive to manufacture, which is easily maneuverable, which is constructed materialwise and structurally to prevent seepage of oil or other pollutants therethrough and to prevent spreading of fires, which has a floatable part ballasted by a depending fin flexible in certain selected regions and more rigid in other selected regions to impart positional stability to the floating part in use against the action of currents and tidal movements and to permit the boom to be folded into compact form for storage, and which is free from pneumatic floatable parts which might be rendered buoyantly ineffective by puncturing or other destructive action.

In accordance with certain features of the present invention, the boom comprises a floating part, and a weighted fin part serving as a ballast for said floating part. More specifically, the floating part comprises a series of elongated bags filled with buoyant material to form floats, and placed in alignment end to end with spaces between adjacent ends. The series of floats are hooded by a flexible fireproof web, wrapped completely transversely around the floats and extending longitudinally across the spaces between the floats. The opposed side sections of the web extending beyond the floats are brought together face to face and secured together to form a curtain depending from the wrapped bags. The two facing components of the curtain form spaced pockets housing weights, so that the resulting curtain forms a fin, which serves not only as a ballast for the floats but also in conjunction with the floats serves as a barrier to confine pollutants, such as oil slicks on the surface of the water. The curtain is flexible in the region just below the floats, so that the curtain is hinged in this region and can swing about an axis parallel to the longitudinal line of the floats relative to the floats. Any submerged currents, tidal movements or waves acting on the curtain causes said curtain to swing about its hinged region without transmitting its motion to the float, so that the float is stabilized against pitching due to the action of such currents or waves.

As a further feature of the present invention, the web forming the hood and the curtain for the floats is thermoplastic material, and opposed regions of this web are heatsealed together, not only for the purpose of conformably shaping the boom around the floats, but also to define smooth flexible regions, which can be easily folded and more rigidized regions, which assist in maintaining the form of the boom and in retaining the floats in spaced position against endwise displacement relative to the web .

Various other objects, features and advantages of the present invention are apparent from the following description and from the accompanying drawings, in which

FIG. 1 is a side elevation of a section of a boom constructed in accordance with the present invention;

FIG. 2 is a side view of one of the filled buoyant bags forming one of the floats for the boom;

FIG. 3 is a section of the bag taken on line 3-3 of FIG. 2.

FIG. 4 is a section of the boom taken on lines 4--4 of FIG. 1;

FIG. 5 is an enlargement of an end section of the boom in the encircled region of FIG. 1, showing a towing connection thereto;

FIG. 6 is an enlargement of an intermediate part of the boom in the encircled region of FIG. 1 where two separable units of the boom have been interconnected;

FIG. 7 is an enlargement of an intermediate part of one of the boom units between floats in the encircled region of FIG. 1;

FIG. 8 shows an end section of the boom taken on lines 8--8 of FIG. 5;

FIG. 9 is a section of the boom taken on lines 9--9 of FIG. 6;

FIG. 10 is a section of the boom taken on lines 10--10 of FIG. 7; and

FIG. 11 is a section of the web forming part of the boom taken on lines 11--11 of FIG. 7.

Referring to the drawings, the boom of the present invention comprises a series of elongated floats 10 covered by a web 11 holding these floats together and forming a keel-curtain 12 suspended from these floats. Each of the floats 10 comprises a bag 13, which is made of a suitable light plastic material, as for example, polyethylene about 4 mm thick, and which is closed at one end 14, as for example, by heat-sealing, and closed at the other end, after being filled with buoyant material 15, by means of a knot 16. The buoyant filling 15, in the specific form shown, comprises beads of foamed polystyrene, as for example, that sold under the trademark Styrofoam. The beads may be 1/8 inch in diameter. Each of the floats 10, in a specific embodiment, may be about 6 feet long and about 6 inches in diameter.

The floats 10 are arranged in spaced alignment end to end, and in a specific embodiment, may be about 2 feet apart. The floats 10 are held in this positional relationship by the web 11, conformably draped over the floats as a hood with side sections 20 beyond the floats brought together and fastened to form the keel curtain 12 depending from the floats. The web 11 is of flexible, thermoplastic, water-proof and water-tight material, which is resistant to petrochemicals or heavy oils, such as bunker C, and which is extremely tough, and will not rip or tear. A suitable material for the purpose is flexible fabric, which is sold under the trademark Herculite; this fabric consists of a sheet of interwoven nylon yarns covered with polyvinyl chloride, is fire retardant and self-extinguishing, can be heat-sealed and sections may be joined, as for example, by electronic welding. The web 11 is of a color to render it highly visible, as for example, yellow.

The web 11 is wrapped substantially snugly completely around the floats 11, and where the side sections 20 of the web come together underneath the floats, these side sections are secured together by heat-sealing in the region 21, as for example, by electronic welding. The heat seal 21 may be about 1 inch wide and extends continuously along the full length of the web 11 spanning the regions between floats 10. The entire boom may consist of a number of units 22, each of which has a number of floats 10 and a one-piece web 11 hooded over these floats. In a specific form, each unit 22 may comprise 12 floats, so that a unit would be about 98 feet long. A number of these units 22 would be joined by easily engageable and releasable connections 23, shown in FIGS. 1 and 6, to permit the assembling of a boom of any desired overall length.

The heat seal 21 on each boom unit 22 extends continuously along its full length of the unit and serves not only to close the web about the floats 10 but also serves to render the region of the heat seal sufficiently rigid, so that wrinkles and bulges along said heat seal are eliminated. With this construction, the region just below the heat seal 21 can serve as a smooth, well-defined hinge, about which the keel-curtain 12, serving as a fin, can swing under the action of undersurface currents and tidal movement without disturbing the position of the floats 10 in the water, as shown in FIG. 4.

The side sections 20 of the web 11 are secured together near their longitudinal extremities by two spaced parallel heat seals 24 and 25, which extend along the lengths of the sections parallel to the heat seal 21 to form pockets 26, and which in the specific form shown may be 1 inch wide. In each of these pockets 26 directly below the corresponding float 10 is a weight in the form of a cylindrical bar 27. These bars 27 may be in solid form, and in the specific form illustrated, may be made of polyvinyl chloride, and may be about 1-5/8 inches in diameter. The bars 27 fit tightly in the pockets 26, so that they are not displaced longitudinally therein, and weight the keel-curtain 12 downwardly to maintain it fully extended when the boom is in use. The section of the curtain 12 between the adjacent edges of the heat seals 21 and 24, in the specific form shown may be about 8 inches wide.

To bring the two facing side sections 20 of the web 11 between the heat seals 21 and 24 close together, so that they will be maintained flat and free of wrinkles and bulges when the boom is in use, these sections are secured together by a heat seal 28 extending substantially midway between the seals 21 and 24, and parallel thereto.

To confine the floats 10 in proper separated positions in the enwrapping web 11 and to define smooth foldable sections free from wrinkles or bulges in the regions 30 (FIGS. 1, 7 and 10) between the floats, each of these regions is collapsed across the full height of the boom to bring the opposed sections of the web in each of these regions in face to face contact, and these opposed sections are secured together by a heat seal 31, located substantially midway between adjacent floats 10. The heat seal 31 extends across the full width of the web including the curtain or fin part 12 of the web, and is flanked by two other heat seals 32, equally spaced from the heat seal 31 to stiffen the region adjoining these heat seals against bending or folding longitudinally of the boom, while rendering the region flexible enough to fold smoothly transversely of the boom. The boom can thereby be transversely accordion-folded compactly along these heat-sealed regions for storage purposes. Two additional heat seals 33 equally spaced from and flanking the group of heat seals 31 and 32, serve to confine the floats 10 somewhat closely in their respective housings defined by the enwrapping web 11. The seals 31, 32 and 33 in the specific form illustrated may each be about 1 inch wide. Eyelets 34 in the regions of these seals permit the use of tow ropes for maneuverability.

The multi-float boom units 22 are connected end to end by means of connections 23, as shown in FIGS. 1, 6 and 9. Each of these connections 23 comprises a bar 35 connected to one end of the web 11 of one boom unit 22 and held between the jaws of a U-shaped clamp 36 connected to the adjoining end of the web 11 of the adjoining boom unit 22. The bar 35 and clamp 36 in the specific form shown, are made of thermoplastic material, as for example, polyvinyl chloride. The bar 35 has a shank 37 clamped between the opposite sections of the web 11 at one end of one boom unit 22 and secured thereto by a heat seal 38. The clamp 36 also has a shank 40 clamped between the opposite sections of the web 11 at one end of the adjoining boom unit 22 and secured thereto by a heat seal 41. The bar 35 and one of the jaws of the clamp 36 have respective interlocking teeth 42 and 43, and the bar and the clamp are brought into interlocking relationship by sliding them relatively endwise transversely of the boom units. Bolts 44 passing through the interlocked bar 35 and clamp 36 assure a firm connection between these members.

Each boom unit 22 has a bar 35 at one end and a clamp 36 at the other end, and the boom units are duplicates to afford ease in assembly. Eyelets 45, 46 and 47 at the ends of the webs 11 permit the boom units 22, while separated, or the assembled boom, to be maneuvered or towed or otherwise handled through the use of shackles passing these eyelets and ropes connected to these shackles.

Heat seals 48 and 50 on opposite sides of each connection 23 assist in closing the web pockets enclosing the floats 10 near this connection and assist in rigidizing these connections, without materially affecting the foldability of the boom in the region of this connection. These heat seals 48 and 50 may be about 1 inch wide in a specific embodiment.

At one end of the series of boom units 22, there is provided a tow plate 51 (FIG. 1, 5 and 8), made of rigid material, such as metal, secured to the connector bar 35 at this end by bolts 52. A pair of aligned holes in the bar 35 and tow plate 51 respectively near the top of the boom receive a shackle 55 with a rope 54 to assist in towing the assembled boom into proper pollutant blocking position.

The boom described is rugged, highly visible, easily cleaned, fire resistant, inert to the destructive action of water or pollutants, water-tight, highly flexible, non-deflatable in the float regions, compressible and well-balanced. The boom maintains equilibrium with its float section on top, while being towed and while in use. The float section does not pitch angularly due to tidal movements or undersurface waves.

Moreover, since the boom units are all duplicates, they can be used as intermediate sections of the assembled boom or by attachment of the two plates described, can serve as the end sections for the boom.

Claims

What is claimed is:

1. A water-floatable boom for oil or other pollutants comprising:

a. a plurality of floats disposed in longitudinal spaced alignment;

b. a flexible web wrapped around said floats and bridging the spaces between said floats,

1. said web being doubled over said floats and having side sections beneath said floats secured together, face to face, to form a flexible curtain depending from said floats;

c. weighting means supported on said curtain near its lower marginal edge whereby the curtain so weighted serves as a ballasting fin for the floats; and

d. a longitudinally extending region disposed immediately below said floats and across the spaces between the floats, said region having a form-sustaining rigidity greater than that of said flexible web to define a hinge axis immediately therebeneath and to effectively isolate movement of said flexible curtain, as caused by action of undersurface water movements, from being transmitted to said floats and the other portions of the boom disposed above said hinge axis.

2. A boom as described in claim 1 wherein:

a. said floats are non-pneumatic and comprised of buoyant material.

3. A boom as described in claim 2 wherein:

a. said buoyant material consists of beads of foamed plastic.

4. A boom as described in claim 2 wherein:

a. the side sections of the web are secured together immediately beneath said floats to snugly enclose them, with the secured portions of the side sections extending longitudinally of the floats and across the spaces between the floats to define said longitudinally extending region.

5. A boom as described in claim 4 wherein:

a. said web is made essentially of thermoplastic material and heat sealed together to define said longitudinally extending region.

6. A boom as described in claim 4 wherein:

a. said web is collapsed in the transverse bridging areas between floats by bringing the opposed sections of the web in said areas close together, to permit the boom to bend transversely about said collapsed regions.

7. A boom as described in claim 6 further including:

a. transversely extending regions disposed in the spaces between said floats and extending across substantially the full height of the boom, said regions having a form-sustaining rigidity greater than that of said flexible web to stiffen the web between said floats against bending and folding longitudinally of the boom except along said hinge axis.

8. A boom as described in claim 7 wherein:

a. said web is made essentially of thermoplastic material and heat sealed together to define both the longitudinally and transversely extending regions.

9. A boom as described in claim 8 wherein:

a. said web material includes a fabric made of woven yarn embedded in a sheet of thermoplastic material.

10. A boom as described in claim 8 wherein:

a. said web has its side sections near its lower marginal edge secured together by two parallel heat seals extending longitudinally of the boom and defining pockets; and

b. said weighting means comprises weighting bodies in said pockets.

11. A boom as described in claim 1 comprising:

a. a plurality of separate boom units, each comprising a plurality of floats and a web wrapped around said floats and each unit comprising means for releasably securing said boom units end to end.

12. A boom as described in claim 11 wherein:

a. said securing means comprises:

1. a bar on each of the units secured to and extending across the end of the latter unit, and

2. a V-shaped clamp for said bar extending across the adjacent end of the adjoining boom unit embracing said bar.

13. A boom as described in claim 12 wherein:

a. said bar and clamp have interlockable teeth.

14. A water-floatable boom for oil or other pollutants

a. a plurality of floats disposed in longitudinal spaced alignment, each of said floats being comprised of an elongated bag of individual beads of buoyant material;

b. a flexible web wrapped around said floats and bridging the spaces between said floats,

1. said web being doubled over said floats and having side sections beneath said floats secured together, face to face, to form a flexible curtain depending from said floats, said side sections of the web also being secured together immediately beneath said floats to snugly enclose them, with the secured portions of the side sections extending longitudinally of the floats and across the spaces between the floats as a longitudinally extending region having a form-sustaining rigidity greater than that of said flexible web to define a hinge axis immediately below the floats to effectively isolate movement of said flexible curtain, as caused by action of undersurface water movements, from being transmitted to said floats and the other portions of the boom disposed above said hinge axis,

2. the double over web also being secured together, face to face, in the transverse bridging areas at locations spaced from the axial ends of said floats to provide tapered outer surfaces to the boom between each of the floats and the bridging areas and to permit the boom to bend transversely about said bridging areas, said secured web in the bridging areas defining transversely extending regions extending across substantially the full height of the boom, said regions having a form-sustaining rigidity greater than that of said flexible web to stiffen the web between said floats against bending and folding longitudinally of the boom; and

c. weighting means supported on said curtain near its lower marginal edge in vertical alignment with each of the floats, whereby the curtain so weighted serves as a ballasting fin for the floats.