A method for surface preparation of composite substrates prior to adhesive bonding. A curable surface treatment layer is applied onto a curable, resin-based composite substrate, followed by co-curing. After co-curing, the composite substrate is fully cured but the surface treatment layer remains partially cured. The surface treatment layer may be a resin film or a removal peel ply composed of resin-impregnated fabric. After surface preparation, the composite substrate is provided with a chemically-active, bondable surface that can be adhesively bonded to another composite substrate to form a covalently-bonded structure.

A method for producing a component with a surface that is suitable for plastic welding or adhesive bonding of two parts is provided. As a preparation step prior to joining, a filler sheet comprising a thermoplastic material or adhesive is arranged on a first surface of a first component and a structuring tool is arranged on the filler sheet. Mechanical force is applied to the structuring tool and heat is applied to the filler sheet such that the filler sheet is attached to the first surface of the first component and such that the structuring tool is partially embedded in the filler sheet. The structuring tool is subsequently removed from the filler sheet to produce a plurality of protrusions in the outer surface of the filler sheet. After surface structuring the first and second components are joined using any type of welding technique or joined using of adhesive bonding.

A method of borehole pipe installation begins with unfinished stick pipes brought to the installation site and then machined or cut to form male and female ends. The pipe ends are then locked together to form a flush joint. The lock can be provided via a groove cut into one of the ends for receipt of a lock gasket, which secures and seals the joint when the pipes are pushed together, and prevents the pipes from being pulled apart. Alternatively, to the groove and lock gasket, the ends can be glued and screwed together, with the screws allowing the joined pipes to be pulled through the borehole before the glue is dry. The pipe joint has flush exterior and interior surfaces to minimize borehole clearance and maximize fluid flow through the pipe assembly.

A method for connecting two components. In this method, a first component and a second component, which are each formed from a thermoplastic material, are first provided. The first component has a first peel-off ply on a first surface of the first component. The first peel-off ply is removed from the first component. Once the first peel-off ply has been removed, the first surface of the first component is brought into contact with a second surface of the second component. The first component and the second component are then welded to one another at the first and second surface by ultrasonic welding.

A method for preparing a pre-bond surface of a composite structure includes the steps of: (1) separating a peel ply, co-cured with a composite substrate, from the composite substrate; and (2) transferring an identifiable marking agent from the peel ply to the composite substrate upon separation of the peel ply from the composite substrate. Residue of the peel ply, transferred from the peel ply to the composite substrate upon separation of the peel ply from the composite substrate, is layered on the identifiable marking agent.

A method and a system including a welding device, an inspection device having an inspection head having two sensors, a controller, and a memory for assessing a butt weld of plastic pipes or fittings in a welding device.

A method for surface preparation of composite substrates prior to adhesive bonding. A curable surface treatment layer is applied onto a curable, resin-based composite substrate, followed by co-curing. After co-curing, the composite substrate is fully cured but the surface treatment layer remains partially cured. The surface treatment layer may be a resin film or a removal peel ply composed of resin-impregnated fabric. After surface preparation, the composite substrate is provided with a chemically-active, bondable surface that can be adhesively bonded to another composite substrate to form a covalently-bonded structure.

A method for making a composite-metal hybrid shaft for a rotorcraft includes providing a tubular metal member that has an internal surface defining a space therein, preparing a composite member using a curing tool, curing the composite member, creating a cured composite member, expanding the metal member with heat, placing the cured composite member into the space defined by the internal surface of the expanded metal member, and allowing the expanded metal member to cool.

A method is described for opening a heat bonded sterile connection that includes a skin of material blocking flow between the connection site. The method includes applying external pressure to the connection site.

Methods and systems are provided for fabricating a composite structure. In one example, the composite structure may include a honeycomb core sandwiched between face sheets. An edge of the honeycomb core may be abraded and a top face sheet may be perforated. As such, a likelihood of delamination of the composite structure during a curing step may be reduced.