Abstract: Piston rod assembly includes a composite piston rod having an entrapment ridge along the length thereof, and a non-integral metallic piston head having two separate piston head sections which are welded together in preloaded engagement against opposite sides of the entrapment ridge. The entrapment ridge has oppositely facing external tapered ramp surfaces which are engaged by correspondingly tapered internal ramp surfaces on the respective piston head sections. When the piston head sections are initially brought into engagement with opposite sides of the entrapment ridge, there is a slight gap between the inner faces on the piston head sections which determines the amount of preload force that must be applied to the piston head sections to eliminate the gap and bring the inner faces into substantial mating engagement with each other for welding.

Abstract: Composite cylinder assembly includes a removable liner assembly consisting of a liner member having circumferential hoop stress windings wrapped thereabout. The ends of the liner assembly freely float on cylindrical end portions on the inner ends of end glands at opposite ends of the cylinder for sliding sealed engagement with ring seals contained in external grooves in such cylindrical end portions. Surrounding the removable liner assembly in radially spaced relation therefrom is a composite outer wall portion having opposite ends threadedly connected to the end glands radially outwardly of the removable liner assembly, whereby disconnecting the ends of the outer wall portion from the end glands will permit removal of the liner assembly as well as the liner seals and outer wall portion for refurbishment and/or replacement as desired.

Abstract: Fluid actuator includes a piston rod comprised of a wound filamentary composite structure to provide an extremely light weight, relatively low cost, envelope efficient design. Attached to the piston rod are one or more non-integral piston heads which are preloaded against one or more ramp surfaces on the exterior of said piston rod. A pair of oppositely facing ramp surfaces may be formed on the piston rod by interspersing filler means between the piston rod fiber layers. Another ramp area may be formed by providing an external groove in the piston rod which is engaged by longitudinally split support shoes that provide an attachment surface for a detachable piston head. An internal ramp may also be provided on the inner diameter of the piston rod adjacent the axial outer end thereof for mating engagement by a conically ramped exterior surface on an internal metal stud used to attach a rod end assembly to the axial outer end of the piston rod.

Abstract: Piston rod assembly includes a piston head and rod which are formed separately and subsequently jointed together by injecting adhesive through a porting passage in the piston head into an annular space formed by an internal groove in the piston head and an external surface of the rod to provide a bonded joint therebetween. The piston head includes a radially enlarged center dam portion and a pair of reduced diameter end portions extending coaxially from opposite sides of the center dam portion. The internal groove extends axially beyond opposite sides of the center dam portion for a substantial portion of the length of the reduced diameter end portions. The reduced diameter end portions are externally tapered radially inwardly from opposite sides of the enlarged center dam portion toward opposite ends of the reduced diameter end portions to provide a gradual build-up of stiffness in the piston head from the opposite ends of the bonded joint toward the middle.

Abstract: Dual tandem composite cylinder assembly includes a cylinder having circumferential or hoop stress windings surrounding a pair of hydraulic chambers in series to react the circumferential loads and prevent diametrical expansion of the hydraulic chambers. Longitudinal tension windings extend over substantially the entire length of the cylinder outwardly of the circumferential windings to react the axial loads which the cylinder must contain. Compressive cylinder composite windings are also provided for carrying compressive loads generated within the cylinder. The hydraulic chambers are desirably lined with removable liner members to facilitate changing of seals and refurbishment of the cylinder.

Abstract: Fluid actuator includes a composite cylinder having circumferential hoop stress windings wrapped about a liner member forming the piston chamber wall, and longitudinal tension windings extending from the outboard end of the cylinder along one side thereof and around the inboard end of the cylinder to the other side and back to the outboard end where they are secured to the cylinder. A compression column of composite material may be provided between a cylinder end wall and a permanent structure mount at the inboard end of the cylinder to extend the length of the cylinder to accommodate a tail stock on the piston of a pressure balanced actuator.

Abstract: A composite pressure vessel including a fluid port directly through the composite side wall structure formed by internally locating a porting fitting in the side wall structure and then inserting a liner member in the interior of the side wall structure. When thus assembled, a void space is provided between a flange portion on the radial inner end of the porting fitting and the liner member which is completely filled with a sealant. Then a porting hole is drilled through the sealant and liner member from the exterior fitting end. A nut may be threaded onto an exteriorly protruding end portion of the porting fitting and torqued to preload the porting fitting against the composite side wall structure. Also, composite material reinforcement may be applied locally around the protruding end portion (and nut).