Mcdermott International, Inc.

J. Ray Mcdermott, S.a.

Mcdermott Incorporated

Other

Mcdermott Technology, Inc.

James Allan Haney

Dennis E Calkins

Robin M Converse

Roger S Osborne

Cheng-Yo Chen

Daniel Major Houser

Daniel M Houser

Stafford J Menard

Chunfa Wu

Trevor R Mills

Larry Dwayne Breaux

Bee-Lay Leow

Charles E Kindel

Raymond J Serpas

A load out and float off method for a spar type structure or another structure such as a deck. The invention enables the load out and float off of a large diameter spar using existing Heavy Lift Vessels (HLV's). A U-shaped tank (U-tank) is utilized to artificially extend the length of the HLV and provide supplemental buoyancy to help lift the spar off the land ways. The U-tank provides supplemental buoyancy and water plane area to float the spar off the HLV. After HLV departure the U-tank is moved and placed beneath an adapter frame on the spar's hard tank. The U-tank is ballasted upward to reduce the hard tank draft and have the strake tips clear the channel bottom. The spar can then be brought alongside the fabrication yard quay for additional work and then towed down the channel to the open sea.

Spar hull load out method

An improved strake for structures that are subject to vortex induced vibrations and motions due to fluid flow around the structure. One embodiment includes a streamliner on the edge of the strake. The streamliner may be added to existing strakes or may be formed at the same time as the strake for extruded strakes. The streamliner reduces vortex induced vibrations and motions of the structure to which the strake is attached. Another embodiment of the invention provides a tension resisting support attached to the strake and structure. The support provides a different load path along the strake than the previously known art for carrying the pressure loading from fluid pressure acting normal to the surface of the strake.

Strakes

An apparatus and method for pressurizing tubular members of an offshore structure immersed in seawater so that the internal pressure resists the hydrostatic pressure of the seawater. To achieve this internal pressure, compressed air or gas is introduced into the tubular members after the various tubular members are submerged in seawater.

Hydrostatic equalization for an offshore structure

A pile driving transition piece. The transition piece avoids the shock loading in the stabbing points of pile driving transition pieces that otherwise would be induced when the pile driving hammer strikes the transition piece. Avoiding the shock loading prevents the characteristic fatigue cracks from forming in the stabbing point and the consequent failure of the stabbing points from rapid growth of the fatigue cracks.

Pile driving transition piece

A method and apparatus that eliminates the need for a derrick barge to lift the deck into place on a floating offshore structure. A connector is used to connect the transport barge to the floating offshore structure. The connector is a type that allows only relative pitch motions between the transport barge and floating offshore structure in response to sea states acting on the barge and floating offshore structure. The connector is also a type that allows disconnection while large forces are acting on the connector. One or more skidding girders attached to the legs of the deck support the legs of the deck above the skidding surface of the transport barge. A skidding surface on the girders, and complementary skidding surface on the surface of the transport barge and floating offshore structure, allow the deck to be skidded from the barge to the floating offshore structure. Once the deck is in the proper position on the floating offshore structure, the deck legs are lowered into contact with the floating offshore structure by removing spacers provided in the girders. The girders are then detached from the legs of the deck and removed. The deck may also be transferred from the transport barge to the floating offshore structure in a manner where relative pitch between the transport barge and floating offshore structure is not allowed. This is accomplished by also using a knee brace that is attached between a submerged portion of the floating offshore structure and the transport barge.

Offshore deck installation

A marine connector that facilitates docking of large floating objects during a sea state that produces significant relative motion between the two objects. A toggle nose is mounted on one floating object and a mating device, a toggle nose receiver, is mounted on the second floating object. The toggle nose contains a toggle mechanism that extends and retracts two opposed transverse pins having conical ends. The toggle nose receiver is provided with corresponding conical sockets to receive the ends of the pins.

Marine connector

A lawn mower is provided having a chassis, a mower deck dependent from the chassis, having a chute for discharging clippings generally in a first direction onto the ground; and a blower assembly mounted to the chassis on the same side as the chute, and having an outlet oriented such that a stream of air from the blower extends along a second direction and intersects the clippings discharged from the chute in the first direction and redisperses the clippings over an area greater than that achieved by the mower deck alone.

Lawn mower with improved clipping dispersal

An apparatus and method for pressurizing the inside of tubular members of an offshore structure that are immersed in sea water so that the internal pressure resists the hydrostatic pressure of the sea water. To achieve this internal pressure, gas is generated automatically on the inside of the members as the structure descends to its in-place location. The gas can also be used to deballast a tubular member.

Hydrostatic equalizer

A pile is plugged at its lower end or tip region so as to make it easier to drive. Additionally, such a plugged pile facilitates the transportation and handling of the pile prior to its driving.

Method of driving a pile

A fixed, non-compliant, non-floating offshore platform subject to lower wave, wind, current, and rig loadings resulting from a configuration that supports the portion of the well casings that extend from near the seafloor to a deck level above the water surface using tension instead of intermediate lateral supports. Only the smallest one or two well casings among all those that comprise the well casing system are extended back from the seafloor, which further reduces the lateral loadings on the structure.

Fixed offshore platform structures, using small diameter, tensioned,

A compliant offshore structure with flex tubes that are not driven into the sea bottom. A foundation template has bottles with skirt pile sleeves and a closed bottom socket. A tower and tower extension support the deck above the water line. The tower legs each enclose a flex tube such that there is an annulus between the leg and flex tube. The flex tube extends below the lower end of the leg so as to be received in the socket. The flex tubes are grouted in place in the sockets to connect the tower to the foundation template. Thickened wall portions may be provided on corresponding sections of the leg and flex tube to provide wear surfaces.

Flex tube compliant offshore structure

This invention pertains to a braced offshore structure that is constructed on land as a single unit in a compact bundle before being transported on a barge to the installation site. After the compact unit is launched, it is unfolded and ballasted before being installed upon the ocean floor. This structure consists of an elongated central tower having a plurality of braces pivotally secured thereto. These braces are initially positioned generally parallel to this central tower within recesses in the central tower but after the braces are unfolded, they extend at an angle to the central tower.

Tower with folding braces for fixed offshore platform

A fixed pile guide having a removable ring gate which restrains a pile within the pile guide. When in the closed position, the ring gate is secured to the guide by means of a pivotable arm. To release the pile and/or to convert the guide to an open pile guide, a cable secured to the arm is pulled which pivots the arm thereby releasing the gate from the fixed guide as well as releasing restraint on the pile.

Removable closure device

An improved removable closure plate arrangement providing a liquid-tight seal in an elongated floatable offshore hollow tubular column structure. The closure plate being adapted for easy removal and including a centrally located pull member removably connected to the upper and fixedly connected to the lower portion of the closure plate with the closure plate being removably connected about its periphery to the inside surface of the column.

Removable closure plate

A mudmat and mudmat removal procedure used in combination with an offshore marine structure for supporting said structure on a soft, unconsolidated seafloor during installation of said structure to the seafloor.

Growing community of inventors

Houston, TX, United States of America

James Allan Haney