GB1377980A - Manufacture of blocks from molten materials - Google Patents

Abstract

1377980 Extruding bitumen or sulphur OCCIDENTAL OEL GmbH 13 Dec 1971 [14 Dec 1970] 57715/71 Heading B5A Molten sulphur or bitumen material, is extruded as one or more strands each into a separate surrounding cooling medium stream, the velocity of which increases to subject the strand to tension in the direction in which it is conveyed by the medium, to be cut by a rotary cutter into shorter lengths which, after removal of coolant, are compression moulded into blocks a whilst in a plastic state. Each block is then enclosed in a protective foil, e.g. of polyethylene for bitumen. In the described embodiment, Fig. 1, molten bitumen from a vessel 1 is extruded, by a pump 2, as a strand 6a from the end of each of a plurality of steam heated nozzles 4, from which water coolant is also discharged around the strand 6a which it conveys along a transparent flexible conduit 6 terminating in a vertically downwardly directed outlet 8, a plurality whereof are circularly arranged around a multibladed rotary cutter 10 which cuts the pieces 6b from the strands. Each conduit 6 is of tapering configuration at 5 around the nozzle 4, at te outlet 8, and at intermediate locations 7 to increase the coolant velocity to convey and tension the strand 6a, and to centre it for the cutter 10. The cut pieces fall through a funnel 11 into a conduit 12 from which coolant separates from the bitumen, through conduit perforations 13 and via a surrounding jacket 14 to an outlet 15. The cut pieces 6b from the conduit 12 are received upon a vibrator conveyer 16 on which they are conveyed, through hot air drying at 17, optionally to a belt weigher 18 which incrementally delivers to the mould of an hydraulic press 19. Moulded blocks 20 are removed from the press 19 by a device 21 and delivered by a conveyer belt 22 into a device 23, for enclosure in the foil and from which a conveyer belt 24 delivers to a stacker device 24, loading on pallets which may be clad with shrink foil wrapper to form a unitary package. The extrusion nozzle 4, Fig. 3, comprises an inner tube 26, through which the bitumen is extruded, surrounded by a jacket 29 through which steam is circulated, via connections 27, 28, and around which is provided an annular space 30 to insulate from an annular passage 38, provided with axially directed vans 38, through which the cooling water from an inlet 39 is directed around the extrusion outlet of the bitumen.