Schwing America, Inc.

Spencer Composites Corporation

Northrop Grumman Systems Corporation

Northrop Corporation

Richard Lloyd Grover

Brian Eugene Spencer

Thomas M Anderson

Lawrence P Schmidt

David R Bissen

Leo B Willner

Richard T Atherton

Zachary B Spencer

Fritz W Wanzenberg

A method of incremental autofrettage is taught herein, whereby the cycle life of a metal liner in a pressure vessel is increased. This method serves to increase the yield strength of the metal liner through sequential work hardening due to repeated autofrettage at increasing pressures. By incrementally increasing the internal pressure used in the autofrettage process, the compressive stresses at an inner surface of the metal liner may be controlled so that post-pressurization buckling does not occur, yet the yield strength of the metal liner is substantially increased. The higher compressive stresses in the metal liner mean that higher Maximum Expected Operating Pressures (MEOPs) may be used without detracting from the cycle life of the metal liner, or alternatively, for lower pressures, a longer metal liner cycle life may be obtained. Either internal or external pressures may be used, generated by a pressure source, or a suitable die.

Products manufactured by autofrettage

Methods for increasing cycle life of metal liners and products manufactured therefrom

The invention relates to improved metal/composite interfaces, particularly for risers used in offshore oil and gas production to connect a subsea oil well to a surface drilling/production facility. The invention provides a composite hoop structure configured to a bearing surface of a metal groove of metal liner over which axial fibers are laid. The composite hoop structure provides for improved transition of axial, torsional and compressive forces between composite fibers and metal surfaces of the metal liner.

Metal-to-composite interfaces

A boom section includes a first, a second, a third, and a fourth fiber reinforced thermoset composite material layer and a flex core layer. The first fiber reinforced thermoset composite material layer has glass fibers in a vinyl ester matrix. The second fiber reinforced thermoset composite material layer is disposed over the first composite material layer and has carbon fibers in an epoxy matrix. The flex core layer is disposed over the second composite material layer. The third fiber reinforced thermoset composite material layer is disposed over the flex core layer and has aramid fibers in a vinyl ester matrix. The fourth fiber reinforced thermoset composite material layer is disposed over the third composite material layer and has glass fibers in a vinyl ester matrix.

Boom utilizing composite material construction

The present invention is a boom system comprising a first boom section having a distal end and a proximal end. A second boom section includes a distal end and a proximal end, wherein the proximal end of the second boom section is rotatably coupled to the distal end of the first boom section. At least one of the boom sections is substantially formed from composite materials.

The present invention is a boom system comprising a plurality of articulated boom sections. Each boom section has a longitudinal axis. A stiffening layer is attached to a surface of at least one of the boom sections, and extends within about ten degrees of parallel to the longitudinal axis of the boom section. The stiffening layer is formed of a fiber-reinforced composite material including a plurality of fibers and matrix material.

Boom stiffening system

Sealed structural joints for use in manufacturing pressurized tank structures, and particularly cryogenic fuel tanks. In a preferred embodiment, the structural joints and seals comprise a strain-compliant material as applied to a joint or seam to provide a surface to bridge the joint with a continuous skin so as to provide a completed bonded inner surface. In the preferred embodiment, the strain-compliant material comprises honeycomb, although foam cores and homogenous elastomeric materials may also be utilized. Among the specific applications by which the joint seals of the present invention may be employed include splice joint seals, frame seals, and access cover openings.

Cryogenic composite tank seals

A robotic positioning device has a support structure and a tool implement holding member which is positional within the three dimensional space of the support structure. The tool implement holding member is connected to the support structure utilizing five positioning members. Each of these positioning members is connected to the tool implement holding member. Three of the positioning members are connected to the holding member at a first common center of rotation and the other two positioning members are connected to the holding member at a second common center of rotation. Each of the positioning members is attached to the support structure utilizing a connecting member which allows for the positioning member to freely pivot with respect to the support structure and additionally allows the member to move with respect to the support structure axially along an axis of the member. This is accomplished by moving the members axially toward or away from the support structure. Because of the movement of the individual members, any tool located on the tool implement holding member can be precisely located with respect to the support structure.

Growing community of inventors

Whittier, CA, United States of America

Richard Lloyd Grover