Abstract: A separator manufacturing apparatus includes a transfer roller (2) with a plurality of annular shaping grooves (1) having a predetermined shape in cross section which are formed in the outer circumferential surface of the transfer roller (2) in its circumferential direction, a resin feeding device (4) with nozzles (3) to feed a hot-melt type resin to the annular shaping grooves (1) of the transfer roller (2), a base paper feeding device (5) to feed a continuous paper (w) at a predetermined speed to the outer circumferential surface of the transfer roller (2) supplied with the resin to thereby form by transfer a plurality of ribs (9) on a surface of the continuous paper (w), and a fault detecting device (6,36,46) to detect the shape and/or a dimension of the rib (9) formed by transfer. A resin drop receiving device (53) or an annular shaping groove cleaning device (63) may be provided so that maintenance of the transfer roller (2) can be easy.

Abstract: A sensor controlled apparatus for making a thin strudel type pastry which mixes, spreads and conveys a thin strudel layer on a film through various process stages such as depositing oil, sugar, cinnamon and nuts filling so that the resultant product can be cut rolled and baked.

Abstract: A separator manufacturing apparatus includes a transfer roller (2) with a plurality of annular shaping grooves (1) having a predetermined shape in cross section which are formed in the outer circumferential surface of the transfer roller (2) in its circumferential direction, a resin feeding device (4) with nozzles (3) to feed a hot-melt type resin to the annular shaping grooves (1) of the transfer roller (2), a base paper feeding device (5) to feed a continuous paper (w) at a predetermined speed to the outer circumferential surface of the transfer roller (2) supplied with the resin to thereby form by transfer a plurality of ribs (9) on a surface of the continuous paper (w), and a fault detecting device (6, 36, 46) to detect the shape and/or a dimension of the rib (9) formed by transfer. A resin drop receiving device (53) or an annular shaping groove cleaning device (63) may be provided so that maintenance of the transfer roller (2) can be easy.

Abstract: Extrudable pharmaceutical mixtures are tableted by a continuous method in which the mixture is extruded and the still deformable extrudate is pressed between two rollers which are driven in opposite directions and possess depressions opposite one another in the roller shell, the form of these depressions determining the tablet shape.

Abstract: An apparatus for producing a coating on a laminar carrier member, in particular for dressing split leather or similar substrates, comprises a supporting base having a surface consisting of silicon rubber or silicone resin, onto which surface is applied a liquid coating material by means of an electrostatic spraying device arranged above the supporting base for the purpose of producing a foil forming the visible side of the coating after solidification of the coating material. The surface of the supporting base is preferably provided with an embossed pattern, for example with the grain structure of natural leather. For the purpose of improving the adhesion of the foil, formed by solidification of the liquid coating material, on the supporting base, the surface of this supporting base is provided with a microscopic roughness. Alternatively, the area of the supporting base adjacent the aforesaid surface is made electrically conductive and held at a predetermined electrical potential.

Abstract: This invention relates to a ravioli making machine. In particular, it relates to an improved method of feeding filler material to a dough lined cavity. The novel feeder tube of this invention is adapted to be utilized with the ravioli machine which has been marketed in the past.

Abstract: A ring tread (12) or a continuous tread (16) may be injection molded in a generally cylindrical segmental mold (20) having a core (42) and radially movable segments (46) forming a mold cavity (54). A container ring (60) is movable into engagement with the segments (46) during closing of the segmental mold (20) to retain the segments (46) during closing of the segmental mold (20) to retain the segments (46) in position during injection and curing. The container ring (60) may have an opening for a continuous tread section to extend from the mold cavity (54) through the side of the container ring (60) and through a space between two of the segments (46). Roller supports on the core (42) support the continuous tread (16) when the segmental mold (20) is opened and sections of the continuous tread (16) are shifted circumferentially through the mold cavity (54).

Abstract: An apparatus and method for producing a conveyor belt made of urethane having reinforcement embedded therein which reinforcement permits the stretching of the belt under controlled conditions. The reinforcement consists of a fabric or a plurality of aligned strands that are embedded in the urethane body of the belt proper that allow for a controlled stretch in the conveyor belt under such fabric or cords limit the stretching of such belt.

Abstract: A tire tread (74,76,194) is injection molded by increments in a mold cavity (56,58,119,224,262) having an open end (110,272) closed by a trailing end (116) of a cured section (114,228). A temperature moderating closed end (109,207,268) prevents complete curing of a trailing portion (116) of the cured section (114,228) while the rest of the section is cured. The mold (14,16,90,188,236) is opened so that the cured section (114,228) may be shifted to a position where the trailing portion (116) is clamped in the open end (110,272) of the mold cavity (56,58,119,224,262). A second section (118,228,264) is injection molded in the cavity (56,58,119,224,262) and the partially cured trailing portion (126) of the cured section (114,228,264) is cured and adhered to the leading portion (130) of the second section (114,228,264) as the second section is cured. This process may then be repeated for later sections to provide a desired length of cured tire tread stock (74,194,264).

Abstract: A method for the continuous production of foam materials, wherein the foaming and/or foamed synthetic starting material is passed through the pressure zone (4) of a continuously operating press (1), and in which method at least a part of the heat required for foaming is produced in the synthetic starting material itself as dielectric heat of an electromagnetic high-frequency condenser field, wherein production of this heat in the starting material takes place at least to its greatest part within a high-frequency condenser field which is arranged in the direction of passage (8) of the material through the press (1) in front of the pressure zone (4), and that in order to supply additional heat into the foaming and/or foamed starting material or in order to prevent or delay its surface cooling, at least one of the electrodes (10, 11) between which prevails the high-frequency field and/or at least one of the pressure surfaces of the press may be heated.

Abstract: An apparatus for making an embossed gypsum panel on a conveyor including an embossing device mounted on a movable device such that the embossing device can be moved to the optimum location for embossing.

Abstract: An apparatus and method for producing a conveyor belt made of urethane having reinforcement embedded therein which reinforcement permits the stretching of the belt under controlled conditions. The reinforcement consists of a fabric or a plurality of aligned strands that are embedded in the urethane body of the belt proper that allow for a controlled stretch in the conveyor belt until such fabric or cords limit the stretching of such belt.

Abstract: Injection molding a tread on an annular tire casing (44) positioned in a mold (10') by introducing a fluid molding compound (76',78') at high pressures and high temperatures into a tread molding space (105) through runner passages (114) extending from an edge (116) to a centerplane (20'--20') of the mold (10') and having gates (118) opening into the tread molding space (105). Alternatively the runner passages (56,58) may be defined by annular runner surfaces (60,62,64,66) in communication with the tread molding space (48) through annular gates (52,54). The fluid molding compound (76,78) may be ejected from annular transfer recesses (68,70) in the mold (10) by squeeze rings (84,86) movable into the transfer recesses (68,70) to introduce the fluid molding compound (76,78) into the runner passages (56,58).

Abstract: A non-metallic leaf spring in which a unitary body member is made up of strands of glass fibers distributed in a matrix of polymerized epoxy resin. The spring is provided with end fittings and a mounting assembly intermediate the ends of the spring by which the spring can be mounted between suspended and unsuspended structures without causing stress concentrations at the non-metallic spring. The method and apparatus by which the spring is manufactured casues strands of fiber to be distributed throughout the spring at a substantially uniform density throughout the longitudinal length of the spring.

Abstract: A method and apparatus for forming a drum handling ring having an inverted frustoconical geometry to facilitate engagement of a conventional parrot beak gripper with the ring. The end of an advancing, straight strip of heated thermoplastic material, continuously provided by an extrusion head, is fed at a first location to the circular periphery of a continuously rotating, large diameter turntable where the strip is clamped thereto and then cooled so that the clamped portion of the strip thermally sets into an arcuate shape corresponding to the periphery of the turntable. At a second location diametrically opposed to the first, the now arcuate end portion of the strip is unclamped and guided away from the turntable periphery to a cutting station where the continuously advancing strip is cut into arcuate pieces each having an arc length generally corresponding to the desired circumference of a drum handling ring.

Abstract: Apparatus for continuously forming individual products pieces containing filler therein and having large perforations in the top layer. A first continuous flat dough sheet is formed and transported on a conveyor belt. Portions of the filler are periodically deposited on the first dough sheet. A second continuous flat dough sheet is formed and transported on a conveyor belt of a material to which the dough of the second continuous flat dough sheet adheres in response to pressure. A device for moving cutting elements through the second dough sheet forms a multitude of holes and presses the perimeter of each dough piece therein so as to adhere to the conveyor belt. An arrangement lifts the second dough sheet off of the conveyor belt means without disturbing the cut out dough pieces adhered thereto.

Abstract: A method for the continuous production of plates and/or shaped bodies of fibre reinforced hydraulic setting masses is described in which the mass is provided in a predetermined thickness over the entire width of the plate to be produced, on a substrate continuously moved by a belt. Fibre cuttings from a cutting device are dispersed in a desired distribution onto the surface of the mass moving with the substrate and these are subsequently incorporated into the mass by a tool acting uniformly over the entire width of the mass. The raw plate can be further processed in its still deformable condition and brought into a desired final shape.

Abstract: The present invention relates to a process and an apparatus for producing phenolic foam laminates with improved surface appearance. The process involves applying pressure on the foam forming mixture through one of its facings by a flexible member. The member is sufficiently flexible to allow continual rise of the foam but also smoothes out any uneven rise under the applied pressure thereby producing a laminate which has a surface immediately below the facing substantially free of any voids, craters or wrinkles.

Abstract: Apparatus for the manufacture of insulating building elements including at least one inner insulating panel and two outer spaced apart concrete slabs having well trimmed outer surfaces, and reinforcements to space apart the two slabs thus forming a continuous cavity. The apparatus rests on a working plane and includes a pair of opposed side boards and two vertically spaced rectangular frames supported by said side boards in superimposed parallel relationship. Connecting devices extend between the frames for positioning each one of the frames in adjustably spaced apart relationship at the level of each concrete slab, and define therebetween an opening through which reinforcements can be introduced or removed.

Abstract: A method and apparatus for forming a drum handling ring having an inverted frustoconical geometry to facilitate engagement of a conventional parrot beak gripper with the ring. The end of an advancing, straight strip of heated thermoplastic material, continuously provided by an extrusion head, is fed at a first location to the circular periphery of a continuously rotating, large diameter turntable where the strip is clamped thereto and then cooled so that the clamped portion of the strip thermally sets into an arcuate shape corresponding to the periphery of the turntable. At a second location diametrically opposed to the first, the now arcuate end portion of the strip is unclamped and guided away from the turntable periphery to a cutting station where the continuously advancing strip is cut into arcuate pieces each having an arc length generally corresponding to the desired circumference of a drum handling ring.

Abstract: Apparatus and method for applying a hot melt adhesive to a web of heat sensitive material in which the adhesive is heated and extruded in a continuous flat bead having a substantially rectangular cross-section onto a rotating chill roll, cooled, contacted by a web of heat sensitive material and thereafter pressed together so that the adhesive conforms to the web material and bonds thereto, and the bonded adhesive and web stripped from the chill roll.

Abstract: Injection molding a tread on an annular tire casing (44) positioned in a mold (10') by introducing a fluid molding compound (76',78') at high pressures and high temperatures into a tread molding space (105) through runner passages (114) extending from an edge (116) to a centerplane (20'--20') of the mold (10') and having gates (118) opening into the tread molding space (105). Alternatively the runner passages (56,58) may be defined by annular runner surfaces (60,62,64,66) in communication with the tread molding space (48) through annular gates (52,54). The fluid molding compound (76,78) may be ejected from annular transfer recesses (68,70) in the mold (10) by squeeze rings (84,86) movable into the transfer recesses (68,70) to introduce the fluid molding compound (76,78) into the runner passages (56,58).

Abstract: A liquid mixture containing a heat-expandable resin and a catalyst is cast onto a lower facing, which is heated from below to cause expansion of the mixture and hardening of its lower part. The upper surface of the expanding mixture is covered with an upper facing applied while that portion is still soft, and the composite formed thereby is introduced to a heated enclosure while the upper part remains soft. The thickness of the formed composite, and panels derived thereof, is calibrated or limited by opposed conveyors within said thermal enclosure, which limits the maximum expansion to a value less than the theoretical potential expansion of the foam, allowing hardening to be completed, and subsequent cutting of the composite into panels.

Abstract: Synchronous conveying belts are formed by modifying teeth grooves of a molding gear used in a molding device employing the gear. A groove plate is configured to fixedly mount in a bottom land of selected teeth of the molding gear for reducing the depth of the selected teeth of the belt to be molded. Sleeves for fixedly attaching the groove plate to the bottom land serve as molding post for forming passageways in the modified teeth extending from a backing of the belt to a top land of the modified teeth. Upon forming the reinforced elastomeric belt using the modified molding gear, transporting devices can be fastened to the backing of the belt using attachment fixtures.

Abstract: A method for continuously producing an insulation board comprising a rigid plastic foam core having two major surfaces and a facing material on one or both of the major surfaces, the method including conveying a facing material along a production line, depositing a partially expanded froth foam of a plastic mixture, which contains at least one frothing agent, on the facing material, and further expanding and curing the froth foam in contact wiht the facing material to form the insulation board. The board is particularly useful as roof insulation.

Abstract: The invention relates to the production of transparent plastic films, sheets or strips of excellent optical quality. It proposes a process for producing these products by casting of a composition suitable for casting on a horizontal, plane casting support, in continuous movement to obtain at least a layer, which after it has consolidated, is detached from its support, turned over, then by casting a composition on the face of the first layer which, when being formed, initially was in contact with the support, to obtain a second layer, the first layer being placed on a horizontal, plane casting support.

Abstract: An annular channel on the circumference of a rotatable moulding wheel is closed with a part-circular covering to form a mould cavity at the commencement of which mouldable material is introduced with an injection nozzle. For the production of reinforced toothed belts with a circumference larger by any desired amount than the moulding wheel circumference, a moulding ring consists of a flexible band, the diameter of which is larger than the moulding wheel diameter. The moulding ring is formed with toothing and a force-transmission element coil is wound on the exterior and has its ends fixed on the moulding ring.

Abstract: In the continuous production of laminates having a texture embossed onto the surface thereof, a pair of resin treated layered webs are brought together at equal speed and an embossed carrier member having a negative of the texture to be embossed thereon is fed between the webs while being unwound from a supply roll. The layered structure formed of the two webs and the carrier member is subjected to compression with subsequent cooling whereupon the outer sides of the laminates are roughened and the webs are formed with a positively embossed or textured surface and are detached from the carrier member and wound on rolls or cut into panels and stacked while the carrier member is simultaneously taken up upon a takeup roll or the like. The carrier member may be moved independently of the webs, i.e.

Abstract: One or more inner bands are employed to cooperate with an outer band and a cavity wheel or inner molding member wherein portions of the inner band or bands together with the outer band and the cavity wheel or inner molding member are utilized to continuously form the cavities for continuously molding articles. The inner band or bands are employed to form core members, intermediate cavity wall portions, and/or stripping members for the molding cavities.

Abstract: In the manufacture of skinned foam a technique for matching the viscosity of the skin as well as the foam so that both flow uniformly through the die includes the addition of blowing agent to all of the layers of the structure. To prevent foaming of the skin layers, nucleating agent is not added at those layers and the temperature is controlled so as to prevent nucleation without a nucleating agent. More specifically, the skins are kept above the boiling point of the blowing agent at atmospheric pressure and melt temperature, but below the temperature at which homogeneous nucleation occurs.

Abstract: A method for continuously making a brush-like material includes winding an adhering filament onto the outer surface of a flexible tubular member. The strands of wound filament and the tubular member are severed about the length of the tubular member to form a planar strip with filament segments adhering and extending across the width arranged in a spaced manner about the length of the planar strip. A portion of the planar strip is removed to expose the ends of the filament segments. The strips holding the filament segments are gathered and stacked in side by side relationship. The strips of filament segments and the exposed tips of segmented filament are immersed in a liquid anchoring material which is cured to secure the filament segments therein. The remaining strips of the tubular member are removed to form a finished strip of brush-like material.

Abstract: A continuous molding apparatus and method is disclosed as providing a sliding seal chamber in which moving molding surfaces form and can provide means for the induction of such temperature changes required to produce finished products from the chosen raw material.

Abstract: In a process for the production of mats made of organic or inorganic fibres, comprising dispersing fibers in a flowing gas so as to issue together from a channel, depositing the fibers on a perforated conveyor belt for the formation of the mat, and removing the gas by suction below the conveyor belt, the improvement which comprises(a) disposing the conveyor belt so as to form an angle of about 90 to 150.degree.

Abstract: A mold for use in molding paint brush heads comprises a pair of mold forming assemblies adapted to form a mold cavity therebetween. Each of the assemblies comprises an upper segment and a lower segment which are adapted to be retained in an end to end relationship, the lower segment having a length through which a bristle knot can be inserted with ease. A molding machine for use in molding ferruleless paint brush heads is also disclosed in which there is provided the improvement of a mold assembly comprising a first pair of molding belts, each having oppositely disposed forward run portions extending continuously through a bristle loading station and then through at least one molding station. The forward run portions of the first molding belts have dividers extending therebetween which form plurality of mold cavities proportioned to receive the proximal end of a bristle knot therebetween. A second pair of molding belts each having a forward run portion are also provided.

Abstract: An insulation filled building plank having two spaced apart boards held together and separated by webs having dovetail connections with the boards and being at an angle to the longitudinal axis of the plank so that any transverse cut of the plank will cut a web is produced on apparatus which first cuts matching dovetail grooves on surfaces of the boards arranged face to face after which the boards are turned to have the dovetail surfaces facing each other and the apparatus pulls dovetails of webs into the grooves in the boards from a magazine and then the apparatus fills the spaces between the webs and boards with an in situ foamable insulation.

Abstract: A process, with the associated apparatus, forms molded articles from binder-containing organic fibres. The process uses pressure to achieve temperatures of more than 100.degree. C. The material is preferably in the form of fibrous mats containing up to 50% heat-hardening binder and having a processing moisture content of more than 5% and preferably 10 to 25%. The compression of the material structure takes place in a single mold stroke, optionally accompanied by additional shaping. With the mold closed, steam pressure is produced during the minimum curing time of the binder in a closed, material-containing volume. The mold is maintained at a superatmospheric pressure. Additional steam can be introduced before or during this time.

Abstract: The invention relates to a method and a device for manufacturing multi-ply sheets of extrudable plastics material supplied by way of at least two webs which are produced by extruders having flat sheet dies and which are bonded to a structured insert web by means of rolls. Moreover, the invention relates to multi-ply sheets thus produced, especially for use with a shower enclosure. In manufacturing such multi-ply sheets it is difficult to obtain a reliable bond between the webs and the structured web without sophisticated machinery. There is also the requirement that the structured web be uniformly introduced between the webs. The invention proposes to feed these webs to a single common set of rolls and to arrange the flat sheet die of at least one extruder so close to a set of rolls that a reliable permanent bond to the structured web and/or at the other web is obtained by the heat accumulated and carried in the one web just extruded.

Abstract: A mixture of binder and fibrous material is introduced into the upper regions of a mat-forming zone. The mixture is intersected by a horizontally or upwardly directed air stream and entrained therein, then layered onto at least one foraminous wire by exhausting the entraining air through said foraminous wire or wires. By reducing turbulence and by controlling the manner in which the particulate matter is deposited upon the foraminous wires, uniform non-woven webs can be obtained which may be used in a variety of ways to form versatile building products.

Abstract: A continuous flexible metal band surrounding a molding wheel and rotating therewith engages the wheel through an arc less than 180.degree., e.g. 110.degree., and is maintained with a substantial inward radius of curvature throughout its entire length. This permits the employment of bands with cavities therein and having thicknesses several times greater than 0.001 times the diameter of the molding wheel without fatigue and failure of the band.

Abstract: An apparatus and a method is disclosed for continuously producing an indefinite length strip of material in a mold with monitoring of such operating characteristics as product temperature, product pressure, product quantity, film temperature, film pressure, film quantity, reaction time, processing time, product through speed, and the like, together with comparing such monitored values with "profiles" of the desired characteristics to provide for close and quick control of such characteristics. The profile is a comparison standard for each characteristic and defined as a fixed curve representing the desired change of such characteristic with respect to another characteristic, for example, the desired variable temperature along the length of a molding apparatus. Most preferably, foam products are produced.

Abstract: Reinforced facings, including reinforcing webs entrained in hydraulic cement via a slurry bath, adhere to a nailable lightweight aggregate cementitious core to form a panel web. The reinforced web is formed on abutting conveyed carrier sheets, and the web is transversely cut, between the sheets, while moving or when stopped, in response to sensing of the sheets. The cut panels, on respective sheets are stacked for curing without damaging the panel edges and in a manner to minimize panel flex. Slurry bath, facing applicators, and cutter and stacking apparatus are included.

Abstract: A process for the continuous manufacture of sheeting from thermoplastic synthetic resins includes the steps of applying thermoplastic synthetic resin, in the form of particles, such as shreds, crumbs, cuttings, pieces, chips, or the like, continuously as a sheet-like layer of raw material to a moving support; passing the raw material layer through a heating zone to thereby preheat the material layer to a temperature approximately in the range from 100.degree. to 140.degree. C.; pressing the preheated material layer continuously over its full area during travel through a treatment zone so that, in a first phase, the raw material layer is compacted and welded under the effect of a pressure of from about 10 to 60 kp/cm.sup.2 and at the same time the material layer is heated to a temperature in the range from about 160.degree. to 220.degree.

Abstract: An insulating element for use in building walls comprises two rigid slabs preferably of brick, and interposed insulating material preferably of expanded polyurethane. The interposed insulation projects out along the periphery of the slabs and is embedded in a complementary recessed part in the insulation of the adjacent element, leaving an interval between the slabs which is filled with mortar in order to unite the slabs. Adjacent elements are pressed against each other during installation in order to reciprocally compress the insulation along the separation plane. The slabs are fed continuously, on edge, in spaced relation, between superposed conveyor belts, thereby to form a tunnel into which the polyurethane is fed and fills by expansion. The slabs are then cut apart by grinding and the insulation is cut along the midline of the slot thus produced, after which the elements are packaged.

Abstract: An apparatus for the production of ravioli and like products characterized by a base, sidewalls rising from the base, a forming roller rotatably coupled to the sidewalls, a platen roller rotatably coupled to the sidewalls in proximity to the forming roller, and means for feeding two sheets of ravioli dough and associated ravioli filling between the two rollers. The forming roller is generally cylindrical and is provided with a cutting grid around its curved surface and a number of ravioli forming areas located within the interstices of the cutting grid. Each ravioli forming area includes a centrally located, saddle shaped relief surrounded by at least one, but preferably two, sealing ridges.

Abstract: A foaming apparatus for manufacturing insulation material includes a mixing chamber, a pump for withdrawing the composition from the mixing chamber and supplying it to the apex of a hollow conical expansion chamber where the apex is located vertically beneath the base of the cone, a cover for the base of the cone including an outlet in the form of a nozzle which imparts a desired shape to the foamed composition.

Abstract: The invention relates to apparatus for manufacturing elements made of a hardenable binding agent, wherein this element is obtained by successive deposits of the dry binding agent in powder form, each deposit being followed by a wetting. The invention is applicable to the production of construction elements, such as plates, tiles, etc.

Abstract: Apparatus for forming, in two steps, panel, or shaped article, by first providing a bath of fluent cementitious material under a core of cellular, preexpanded and cohered polystyrene cells or pearls, having a density less than that of the cementitious material, allowing the core partially immersed to rise in a controlled way over the cementitious material, maintaining the core under pressure until the bath has partially set to prevent further rise of the core, pouring onto the core and partially set bath, a second quantity of fluent cementitious material to completely enrobe the core and form thereover a top revetment, smoothing the surface of the second quantity of cementitious material and letting it set to complete the panel.

Abstract: One or more inner bands are employed to cooperate with an outer band and a cavity wheel or inner molding member wherein portions of the inner band or bands together with the outer band and the cavity wheel or inner molding member are utilized to continuously form the cavities for continuously molding articles. The inner band or bands are employed to form core members, intermediate cavity wall portions, and/or stripping members for the molding cavities.

Abstract: The present invention concerns the manufacture of objects made of plaster, essentially in the form of boards and, specifically, the pouring onto a moving conveyor of a mixture of plaster and water into a reservoir with an open bottom installed on top of said conveyor.It proposes to integrate the upstream rear wall of the reservoir within a surface of greater dimensions than the rear wall, and displacing said continuously, with the purpose of presenting a different portion of the surface as the upstream rear wall.The invention allows continuous cleaning of the upstream rear wall without disturbing the pouring process.

Abstract: The disclosure relates to an apparatus for applying a polymeric covering to a workpiece such as a cylindrical workpiece (10). In order to apply smooth surfaced coating firmly bonded to the workpiece in a single operation the workpiece is rotated in a lathe about an axis (11) and a rubber applying head is traversed parallel to the axis along the workpiece. The head has a freely rotatable tapered feed roller (19) forming a nip with the workpiece to apply polymeric material to the workpiece, a main roller (23) adjacent the feed roller and also forming a nip with the workpiece to pressurise and render plastic the rubber coating applied by the feed roller to masticate and compound the layer, a pressure surface (24) adjacent the main roller and incorporating a retractable plough (25) to dig into the rubber coating and release any entrapped air and a finish roller (26) to apply the required surface finish to the rubber coating.