Method of making laminated reinforced thermoplastic sheets and articles made therefrom

separate vertical tracks past a number of stations including a loading station where an oriented charge of chopped filament loaded resin is deposited in the female part ; a mould closing station ; a curing station and a mould opening station which has the means to eject the article from the female part. The mould parts are in an indexed relationship and exert enough pressure to compress the charge into a unitary article whilst they move through the curing station, otherwise they are spaced apart.

Plant to manufacture elongated elements of prestressed reinforced concrete Zan A.M. (S.C.A.C. Societa Cementi Armati Centrifugati SpA, Milan, Italy) US Put 4 952 129 (28 August 1990) The plant is comprised of a plurality of parallel tracks on each of which there is at least one slidable elongated support carriage. Each carriage has a means for positioning and tensioning reinforcement and prestressing strands on it. There is a sheltered work area in a central portion of the tracks where a series of operating machines are positioned which can move transversely above the tracks. Each of the machines is fixed with respect to the longitudinal axis of the tracks and performs a predetermined operation on a plurality of aligned forms whilst the carriages are moved along the tracks. The machines include at least one concrete caster and a tensioning machine. There is a curing area for the cast forms positioned externally to the working area.

Process for the manufacture of a tyre reinforcement Debroche C. and Laurent D. (Compagnie General des Etabhssements Michelin, Clermont-Ferrand, France) US Pat 4 952 259 (28 August 1990) The reinforcement is produced on the outer surface of a self-adhering element, which defines the geometry of the reinforcement, by projecting adjacent self-adhering cords individually into their places in the reinforcement.

Hose construction Washkewicz D.E. and Belofsky H. (Parker Hannifin Corporation, Cleveland, OH, USA) US Pat 4 952 262 (28 August 1990) A continuous thermoplastic core tube is extruded and one or more layers of closely spaced ferrometallic wires are wound over the core. The whole is heated in a controlled fashion such that the extrusion of core tube material into the spaces between the windings is less than one half the thickness of the reinforcement. Whilst the temperature is maintained an outer thermoplastic cover is pressure extruded over the reinforced core tube to form a composite host structure which is then cooled. Method of manufacturing prestressed concrete culverts Kitzmiller J.K. (Gifford-Hill & Company, Inc., Dallas, TX, USA) US Put 4953 280 (4 September 1990) Culverts comprise of two side sections and a top section are cast upside down in a cavity comprised of a casting table with sidewalls in which at least one prestressing tendon is placed and two side sections in which reinforcing steel is placed. After casting the prestressing tendons are cut and the sidewalls that define

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the cavities are removed. are then removed.

The modular

culverts

Method of manufacturing a cable-like plastic composite body Olesen J. and Jorgensen J. (Roblon A/S, Frederikshavn, Denmark) US Par 4956039 (II September 1990) A number of continuous high modulus filaments are gathered together in a parallel fashion to form a core string. This is impregnated with a hot melt adhesive and whilst the adhesive is still soft the whole is wound with a high strength yarn to form a wound core string.

Method of making roofing piles, including method of applying same to a roof Ruisi S.J. (10 Dunton Ave., Deer Park, NY 11729, USA) US Par 4956199 (II September 1990) Continuous fibre-glass mat is fed through a punching die so that about one third of its width has holes punched in it. The mat is then impregnated with melted asphalt at a temperature of about 230°C whilst the mat is mildly stretched. Granular material is applied to the heated saturated mat which is subsequently cooled. Polyester composite propellor spinner and method of making same Paul R.D. and Pollock W. (United Technologies Corporation, Hartford, CN, USA) US Pat 4957415 (18 September 1990) An improved method for producing an impact hardened polyester composite propellor spinner which consists of adding a vinyl terminated liquid reactive compound to the polyester resin and combining the resin with about 35 weight % randomly oriented glass fibres. The fibres are about 5 cm and 10 cm in length and are present in 1:2 ratio respectively.

Apparatus for the manufacture of sections of thermoplastic resin reinforced with continuous gbres Glemet M. and Cognet G. (Societe Atochem, Puteaus, France) US Pat 4957422 (18 September 1990) An apparatus which is comprised of a channel with a coating zone wherein the fibres are coated, followed by an impregnation zone with two baffles that are opposite and parallel to each other and a shaping zone downstream of this where the articles are shaped. Upstream of the coating zone there is a baffle zone with at least one baffle that is parallel to the impregnation zone baffles. High pressure lamination chamber Semff L.R. (Texas Instruments Incorporated, Dallas. TX. USA) US Put 4957585 (18 September rb90) ’ A device comprised of a vessel capable of containing pressurised solid granular material with a shaping tool mounted on it which can receive a resin containing material. A pump applies a pressure level of up to about 0.36 MPa in order to compress the solid granular material aginst the resin containing material and a mechanical compression system is used to increase the pressure to about 21 MPa thereby causing the resin containing material to conform to the tool shape.

Method of making laminated reinforced thermoplastic sheets and articles made therefrom Biggs IS. and Radvan B. (The Wiggins Teape Group Limited, Basingstoke, UK) US Put 4957805 (18 September 1990) Two unconsolidated thermoplastic sheets containing 20-60 weight % high modulus reinforcing fibres are prepared together by making a first stock of reinforcing fibres and thermoplastic particles; depositing this stock on the wire of a papermaking machine and partially draining it. A second stock of reinforcing fibres and particulate thermoplastic is deposited on the partially drained material and the two are drained and dried together to produce a pair of sheets in which projecting fibres from adjacent sheets engage in a boundary zone. Heat and pressure are then used to form a laminate. Process to manufacture a reaction resin cement building material mixture Marohn H. (Am Eichenkamp 13, D-4150 Krefeld. Germanv) US Pat 4957951 (18 September 1990) - ’ An aggregate material is coated with a liquid epoxy resin and then covered with pulverised aggregate powder. Similarly an aggregate material is coated with an epoxy resin hardener and then covered with pulverised aggregate powder. The two resulting dry premixes are mixed to form the building material. Alternatively liquid epoxy resin or hardener are cooled, ground and mixed with pulverised aggregate to form either coated resin or hardener. Corrugated roofing sheets of synthetic fibrereinforced cement, with a rough surface due to the presence of granular mat&al Magnani S. (CIF Comoaenia Italiana Fin&ziaria Spk, Italy) Vi &t 4960616 (2 October 1990) A mixture of cement, water and inert materials is prepared and applied to a mesh of synthetic fibres which is supported on an advancing felt or cloth band. A granular material is applied to the top surface before the cement has set and excess water is removed from the layer which is then corrugated. The layer is then cut to form sheets of the desired length and the top surface brushed to remove any unadhered granular material. Reinforced ceramic cutting tools Rhodes J.F., Dziedzic C.J. and Beatty R.L. (Advanced Composite Materials Corporation, Greer, SC, USA) US Pat 4961757 (9 October 1990) Alumina powder is mixed with 2-40 volume % silicon carbide whiskers and pressed at a pressure of 20-430 MPa into a shape with at least one edge. This is then sintered at 815-1760°C and the edge is finished to produce a cutting edge for metal. Manufacture of creep-free prepregs based on phenolic resins Boinot F. and Cousin M. (Norsolor, Paris la Defense, France) US Put 4962166 (9 October 1990) Fibrous reinforcing agents are impregnated with a solvent free phenolic resole resin containing about 85% solids. The viscosity of the resin changes by a maximum of a factor of 50 in the first 24 hours and by a factor of 2 in the next 24 hour period; it is controlled by an additive of lithium metaborate, an alkaline earth metaborate or a mixture thereof

Composites Manufacturing No. 2 1992