Abstract:
An apparatus for removing attachments deposited on a surface of an underwater structure and preventing that such attachments be deposited thereafter. The apparatus is floated on the water surface or underwater and with the aid of a natural force repeatedly impinges upon the surface of the structure to remove attachments deposited thereon. The apparatus has a first rope being provided around the surface of the structure at the water surface level, and at least one or more rotating members threaded with said first rope and being freely rotatable about the rope. The rotating members impinge upon the surface of the structure when the apparatus floats on the water surface level or underwater shaving off attachments deposited on the structure, and preventing any further attachments from being deposited thereafter. It is preferred to provide some protruding portions on the surface area of the rotating members where the rotating members impinge upon the surface of the structure.
Abstract:
A hanging articulated mat assemblage disposed between pilings or on a support structure using a plurality of elements connected with flexible rope to each other and to a support beam which permits the mat to swing freely while supporting substantial weight, and optionally using a nonabrasive pad disposed on selected faces of the elements to prevent abrasion while swinging of the mat.
Abstract:
This invention relates to a method of preventing or controlling aquatic attaching fouling organisms which comprises covering aquatic organisms attaching portions on the surfaces of submerged structures or intake facilities with a plurality of mutually insulated metallic covers made of iron, magnesium, aluminum or their alloys through an insulating material and a cushion; using each of the metallic covers as an electrode; forming an electric circuit using the metallic covers facing each other as a pair; connecting the electrodes to a D.C. power supply having a polarity reversal function so as to supply a current between both poles either continuously or intermittently; and reversing the polarity of the current so that when one of the metallic covers is an anode, the surface of the metal constituting the metallic cover is dissolved and activated, and attachment of the aquatic fouling organisms to the surfaces of the metallic covers is prevented or controlled.
Abstract:
A concrete or the like mattress for laying over a pipeline on the seabed comprises an elongate recess or tunnel (5) having an insulating material (6) located therein. The mattress is laid over a subsea pipeline so that the pipeline is received within the insulant-containing tunnel. The pipeline is thus physically protected and thermally insulated. The mattress can comprise a plurality of concrete or like members (1,2,2',3,3') articulated together.
Abstract:
Apparatus for preventing re-growth of marine fouling on offshore marine structures comprises one or more flexible, multi-component collars adapted to surround a submerged structural support member of the marine structure. The apparatus is "powered" by the utilization of ocean forces in the form of waves, swells, tides and currents, whereby marine growth is prevented from re-establishing one the structural support member by virtue of the reciprocating motion of the apparatus about the member.
Abstract:
A substantially continuous copper-containing antifouling surface is formed on a marine structure by attaching thereto a composite comprising a plurality of strips of copper (or copper alloy) mounted side-by-side on a support. The composite may be adhered to the structure or it may, for example, be applied to an uncured neoprene coating on the structure which is subsequently cured.
Abstract:
Protective barrier consisting of at least two ballastable elements (3, 4) adapted to surround at least partially the work to be protected (1).The height of the individual elements is greater than the water depth. The elements comprise a connection device permitting the structural continuity of the elements after assembly. The protective barrier is entirely independent of the work to be protected. The positioning of the elements around the work is effected by means of a positioning system provided in the sea bed and/or the individual elements of the protective barrier.
Abstract:
An anti-fouling surface structure having a multiplicity of ribbons made of plastics thin film and planted on a surface and a method of planting ribbons on a substrate. The ribbons fixed to the surface flutter in sea-water so as to prevent marine growth on the surface. The anti-fouling surface structure may be realized by directly planting ribbons on the surface of a structure to be protected or covering the surface of the structure by a covering material which has a multiplicity of ribbons planted on a substrate sheet or string. The method of planting ribbons comprises the steps of slitting a wide film into a multiplicity of parallel ribbons, flexing and folding the multiplicity of ribbons simultaneously in the direction perpendicular to the slitting direction thereby forming crests ribbons on opposite sides, bonding the ribbons to a substrate at their crests on one side, and cutting the crests opposite to the bonded crests. The method may be such that different substrates are bonded to the crests of the ribbons on opposite sides and then the ribbons are cut at their portions intermediate between the bonded crests.
Abstract:
A landing adjustment system for offshore marine structures is disclosed herein. The system comprises a plurality of columns extending downwardly from the underside of the offshore marine structure and having the lower ends provided within the columns, the buoyancy by the tanks resting on the sea bed and buoyancy tanks being individually adjustable.
Abstract:
A movable fixed-type semi-submerged construction includes a plurality of legs each having a spat tank attached to its lower end and sunken to rest on the bottom of the sea and a superstructure supported on the legs. A scouring preventing structure including a cylindrical circumferential wall formed with a large number of holes therethrough is arranged at the lower part of each of the legs so as to encircle the spat tank.