A threaded shaft for a ball screw comprising: a shaft of fibre-reinforced polymer material; and a helical ridge formed on an outer surface of said shaft, said helical ridge being formed from a fibre-reinforced polymer material comprising a plurality of helical fibres wound around the shaft in the same sense and grouped together to form the ridge. The helical ridge formed from grouped helical fibres all wound with the same sense provides excellent axial load carrying capability as the fibres run continuously from end to end of the shaft and can thus transmit load from end to end. This adds much greater strength than a shaft formed from plastics only. The load carrying capability of the fibre wound helical ridge can indeed approach that of existing metal threads while still being much lighter in weight.

A fastener is provided. In another aspect, a fastener is made of layers of material, a light curable material and/or multiple built-up materials. Another aspect uses a three-dimensional printing machine to emit material from an ink jet printing head to build up a fastener.

A fastener is provided. In another aspect, a fastener is made of layers of material, a light curable material and/or multiple built-up materials. Another aspect uses a three-dimensional printing machine to emit material from an ink jet printing head to build up a fastener.

A fastener is provided. In another aspect, a fastener is made of layers of material, a light curable material and/or multiple built-up materials. Another aspect uses a three-dimensional printing machine to emit material from an ink jet printing head to build up a fastener.

A method for preparing an article includes at least a first component of a polyolefin in conjunction with a second component of a polymer made by ring-opening metathesis polymerisation of norbornene type monomers. The method includes pre-treating a surface of the first component, applying a ring-opening metathesis polymerisable mixture of norbornene type monomers and a catalyst to the surface, and curing the ring-opening metathesis polymerisable mixture in contact with the surface, wherein the ring-opening metathesis polymerisable mixture has a .sub.1000 at 30 C. of more than 9 sec. Articles such as a pipe line field joint or a protective element for a concrete tunnel lining element can be made using the method.

The disclosure features structural tiles and methods for forming such tiles, the tiles including a tile body featuring one or more polystyrene materials, and a coating featuring an epoxy resin and an aggregate material, disposed on at least one surface of the tile body, where the structural tile has a dry coefficient of kinetic friction of at least 0.75 and a wet coefficient of kinetic friction of at least 0.70, and where the dry coefficient of kinetic friction is larger than the wet coefficient of kinetic friction by 0.05 or less.

A direct write dispensing nozzle assembly and method of forming traces and twisted pairs via direct write dispensing. The method includes dispensing conductive material via an inner nozzle so as to form a conductive core. Non-conductive material may be dispensed via a peripheral nozzle surrounding the inner nozzle so as to form a non-conductive casing surrounding the conductive core. The first conductive core and the non-conductive casing may then be deposited on a substrate or other surface. The trace may be positioned on the substrate such that the non-conductive casing contacts a previously deposited trace. An additional conductive core may be dispensed within the non-conductive casing and the direct write dispensing nozzle assembly may be rotated so as to form a twisted pair.

Fastening devices are described. In one example, the fastening devices can be used for a landing string buoyancy solution. The landing string hardware includes a stop collar to be fitted and secured around a drill pipe and stop collar hardware to secure the stop collar together around the drill pipe. The stop collar can be secured at one end of a number of buoyancy modules placed along a longitudinal length of the drill pipe to hold them into place along the drill pipe. The stop collar can be formed from long fiber thermoplastic using extrusion-compression molding. The stop collar hardware includes a bolt having an external thread formed from long fiber thermoplastic and a nut having an internal thread formed from long fiber thermoplastic. Both the stop collar and the stop collar hardware are tested for suitability for the application of holding the buoyancy modules in place under operating conditions.

Composite fasteners have a high fraction of discontinuous, randomly oriented reinforcing fibers. A charge of thermoplastic fiber flakes are heated to melting temperature within a reservoir, flowed into multiple mold cavities and compression molded. The molded fasteners have high strength, exhibit quasi-isotropic properties and may be produced in high volume.

A thread forming apparatus for forming threads in a rotational molding apparatus comprising a molding pin having a generally elongate shape, at least a portion of the molding pin having a threaded portion, the molding pin adapted to rotate along with the mold and receive the plastic material on at least the threaded portion, the molding pin being releasable relative to the mold such that once the plastic material coats the threaded portion of the molding pin and forms a threaded portion on the molded product, the molding pin is completely removed from the mold.