Abstract: A laser groove machining method for forming bottomed grooves in a surface of a workpiece using a laser, wherein an emitting position of a laser beam which is to be emitted onto the workpiece is shifted relatively along groove forming positions at a high speed of 150 mm/min. or faster. Thus, melted portions which are melted by the laser beam can easily be separated, cooled and removed by shifting the laser beam emitting position at high speed. In addition, water may be jetted to the workpiece so as to form a pillar of water so that the laser beam is emitted through the interior of the pillar of water so formed.

Abstract: The invention provides a spinnerette assembly for forming multicomponent hollow fibers of the sheath/core type. The spinnerette assembly contains an extrusion orifice and a core forming material passage in communication with the extrusion orifice. A hollow needle extends through the extrusion orifice in a concentric manner to define an annular passage surrounding the needle. The core forming material passage includes a core forming material inlet port extending from a surface of the spinnerette assembly to an interior of the assembly and a transverse passage extending from the core forming material port to the annular passage surrounding the needle. A bore forming fluid passage communicates with the interior of the needle. The spinnerette assembly contains at least one sheath forming material passage also in communication with the extrusion orifice.

Abstract: An apparatus for manufacturing stiffness-taper tubing includes a die having an extrusion hole, a die holder for holding the die, and a mandrel mounted inside the die holder and that fits in the extrusion hole. The apparatus forms stiffness-taper tubing by switching between and supplying resins having different stiffnesses over the mandrel from a plurality of resin-supply ports formed in the die holder such that the stiffness gradually changes in the lengthwise direction. A mandrel insertion hole connecting to the extrusion hole is formed in the die holder and the mandrel is mounted in this mandrel insertion hole. The plurality of resin-supply ports open to a cylindrical space formed between the inner surface of the mandrel insertion hole and the outer surface of the mandrel at a position separated from the extrusion hole in the die, and the plurality of resins flow together in this space.

Abstract: There is provided ceramic honeycomb body including a plurality of parallel cells defined by intersecting internal walls, and arranged in horizontal and vertical rows at and between opposing ends of the honeycomb body, an outer peripheral wall surrounding the cells, and further being interconnected to the internal walls, wherein the cells are divided into a first region including a portion of the cells adjacent the outer peripheral wall, and a second region including the remaining cells, wherein the cells in the first region have a wall thickness that is continuously increased along an axis extending to the outer peripheral wall, and, wherein fillets are formed at least at intersections between the interior walls in the first region of cells.

Abstract: An extrusion apparatus which satisfactorily adjusts differences in skin-body flow rates at multiple locations around the die, and allows for the external manipulation of the interior components controlling batch flow, during the production without having to stop manufacturing operations to effect the necessary changes thereat.

Abstract: An apparatus for producing a honeycomb structure having an extruder, at least one cradle and a cutting device comprising a small-gage wire for cutting the honeycomb structure and a notching member; said cradle is provided with a means capable of moving the honeycomb structure extruded from the extruder in the lengthwise direction of the honeycomb structure at nearly the same speed as the extrusion speed of the honeycomb structure, said cutting device is constructed so that the cutting small-gage wire is moved to the honeycomb structure side on the same plane as the plane of stretched small-gage wire, a cutting induction groove is formed on the outer peripheral side surface of the honeycomb structure by the notching member, and immediately thereafter the cutting small-gage wire is positioned in the induction groove, and the cutting small-gage wire is pressed into the honeycomb structure to cut the honeycomb structure.

Abstract: A honeycomb structure molding die that can mold a thin-walled honeycomb structure without degrading the moldability has been provided. A honeycomb structure molding die 8 comprises at least supply holes 81 to supply materials and slit grooves 82 that are communicated with the supply holes 81 and mold the materials into a honeycomb shape, wherein the groove width of the slit grooves 82 is not more than 100 &mgr;m and simultaneously, recesses 41 and protrusions 42 that extend in the direction in which the materials are extruded are provided on a pair of opposing side surfaces 820 of the slit grooves 82.

Abstract: The present invention comprises an improved extruder die assembly and method for using same to improve the quality of dimensional design aspects of extruded, complexly shaped, direct expanded food products. The improved system includes an improved extruder die assembly comprising an imprinting insert element having a first aperture defined therethrough and at least one prong extending into the first aperture, and a forming insert element having a second aperture defined therethrough and positioned downstream from the imprinting insert element, wherein the shape of the second aperture is defined by at least one projection extending into the second aperture, and wherein each of the at least one projection aligns with a prong when the first and second apertures are coaxially aligned. The improved extruder die assembly of the present invention is designed for adaptation to a wide variety of commercial-grade extrusion devices common in the food industry.

Abstract: Multilayer plastic composites containing at least two incompatible plastics, A and B, in which the layering sequence alternates between A and B, the layers of plastic B are discontinued at regular intervals, and the resulting gaps in the layers are filled in with plastic A, exhibit good adhesion between the layers. In preferred embodiments of the invention, the amorphous, crystalline, or semi-crystalline plastic B has a higher coefficient of thermal expansion than the amorphous plastic A. The plastic composite is preferably produced via coextrusion.

Abstract: Extruded honeycomb products are formed by means of an extrusion die incorporating a pin support section positioned between the die body and the pin array forming the die discharge slots, the pin support providing enlarged support segments that improve pin stability and die resistance to pin damage without overly restricting batch flow through the die.

Abstract: An adjustable extrusion die shapes a melt into a non-circular cross-sectional profile form. The wall thickness of the profile is adjustable by moving two adjustment plates orthogonal to each other and transverse to the flow of the melt. Movement of each adjustment plate is restricted to prevent rotation relative to a melt-shaping bushing.

Abstract: A die apparatus, a method of using the die apparatus to produce co-extruded polymeric articles, and co-extruded polymeric articles produced using the die apparatus and method are disclosed. The die apparatus includes a hollow vane configured to extrude a material into a chamber within the die, thereby producing a co-extruded web. The co-extruded web has a plurality of distinct, discontinuous phases in the cross-web direction, the phases having a uniform width as shown by a coefficient of variation of less than 8 percent for any three consecutive phases. The phases are substantially continuous down-web and are surrounded by a matrix having two or more layers.

Abstract: An apparatus for manufacturing a honeycomb structure having slits and a plurality of arrays of numerous cells aligned in parallel, wherein the slits communicate with external space and are formed along the cell arrays. The apparatus includes an extruder having an extruding die for a honeycomb structure, and a slit forming member arranged near the extruding die and protruding along arrays of a molded article being extruded in which slits are to be formed.

Abstract: An extruding coating method comprises steps of feeding a coating liquid into a coating liquid reservoir section provided with a slit having a slit width; and extruding the coating liquid through the slit so as to conduct coating, wherein the coating liquid is extruded through the slit by pushing the coating liquid in the coating liquid reservoir toward all over the slit width by a piston.

Abstract: A die for extrusion molding of a honeycomb which comprises a structure provided with a groovy slit (2) formed by cell blocks (3) on a front face thereof, and additionally provided with a puddle inlet, on a back face thereof, communicatively connected with the slit (2), wherein each cell block (3) has a soft film (16) on a hard film (14) formed on outermost surfaces of the slit (2) and puddle inlet fabricated in a cell-block body (10). According to the die for extrusion molding of a honeycomb, a dimensional error of the die is possible to be eliminated, a stable force of extrusion friction is possible to be maintained, both extrusion moldability and abrasion resistance are possible to be excellent, and additionally an adjustment of the die at the time of extrusion molding can be performed easily.

Abstract: To provide a method of producing a uniaxially stretched polytetrafluoroethylene gasket tape, which comprises: (1) a step for preparing a paste comprising a mixture of a polytetrafluoroethylene powder obtained by emulsion polymerization and an extrusion aid, (2) a step for extruding the paste by means of an extruder equipped with a die which has plural separators inside an orifice thereof having a rectangular cross section, (3) a step for rolling, in the extruding direction, an extrudate having slit lines to give a rolled polytetrafluoroethylene sheet, (4) a step for uniaxially stretching the rolled sheet in the rolling direction after removing the extrusion aid from the rolled sheet, and (5) a step for heat-treating the obtained uniaxially stretched polytetrafluoroethylene sheet. The die of the extruder has plural sheet-like separators in the orifice thereof having a rectangular cross section.

Abstract: An extruder die head for producing multilayered tubes made of thermoplastic material exhibits a central annular channel, which is provided with an annular outlet die. Into the outer limiting wall of the channel empty annular slits, which feed a polymer melt and which constitute the smaller diameter openings of truncated channels, formed between the internal and external shells of stacked, conical insert members. To reduce the axial length of the extruder die head, the annular slits, feeding the polymer melts, also empty into the inside wall of the central annular channel. The annular slits are the smaller diameter openings of truncated channels, formed between the internal and external shells of stacked conical internal insert members.

Abstract: A honeycomb structure which includes an inlet end and an outlet end opposing each other and a plurality of cell channels extending along an axis from the inlet end to the outlet end, the cell channels having non-equal, square cross-sections, and an extrusion die for making the same.

Abstract: An extrusion die for extruding plastic material as a tubular film has mututally engaging first and second body members which form an annular extrusion orifice therebetween. One of the body members has main feed grooves in a surface thereof adjacent the other body member and extending in a spiral manner relative to the annular extrusion orifice, and one of the body members has supply grooves in a surface thereof adjacent the other body member for receiving plastic material from one or more extruders. Each supply groove has an end portion adjacent but spaced from an initial portion of a main feed groove, whereby plastic material from the extruder or extruders is received by the supply grooves and forced from the end portions thereof along a passage between the body members and into the initial portions of the spiral feed grooves.

Abstract: An apparatus for producing a ceramic molding having a desired shape by extruding a ceramic material includes a screw type extruder and mold connected to the distal end of the extruder through a resistance pipe. The ceramic material is pressure-fed from the extruder into the resistance pipe and is heated or cooled from round the periphery of the resistance pipe to control the shape of the ceramic molding extruded from the mold.

Abstract: A metal mold for molding a hexagonal honeycomb structure, having feed holes for feeding a material, pool grooves formed in the shape of a triangular lattice and communicated with the feed holes, and slit grooves formed in the shape of a hexagonal lattice and communicated with the pool grooves. Each hexagonal lattice of the slit grooves is so formed as to come into agreement with a hexagon shaped by combining six triangular lattices of the pool grooves.

Abstract: A die module is constructed for an extrusion die which provides for the adjustment of the concentricity of the exit configuration by allowing relative movement of the die within the extrusion die assembly. The die is mounted on a die holder through a pair of mounting rings which fit into a recess in the die body. The rings are constructed with interface surfaces having a curvature with a center upstream. The interface surfaces form a seat within which the die holder is contained with mating surfaces engaging the interface surfaces to allow pivot motion about the center of curvature of the interface surfaces. The engaging surfaces are in the shape of a partial hemisphere to simulate a universal motion. Adjustment bolts are located in the extrusion die assembly downstream of the interface. Bolts, which secure the rings to the die holder, are constructed to provide a fixed spatial relation of the engaging surfaces.

Abstract: A device for extruding and blow-molding thermoplastic tubular components with an extrusion head. The head has a central stem which is perforated in an axial direction. A distribution body lies radially around the stem so as to radially distribute the stream of thermoplastic material. An annular extrusion port is arranged downstream. The invention allows to avoid stagnations of material and to easily adapt the device to various types of thermoplastic material.

Abstract: An annular die designed to produce polymer foam using only one or more ambient gasses as a blowing agent includes an exiting channel with an exit having a cross-sectional area between about two and about ten times that of a smallest point within the exit channel. The section of the die from the smallest point to the exit is thermally isolated from the rest of the die, and the temperature thereof is independently controlled. In addition, the interior surface of the exit channel is coated with a friction-reducing coating.

Abstract: An extrusion die for a hollow member includes: a male die for defining a plurality of hollow portions of the hollow member, the male die including an annular base portion and a bridge portion bridging the annular base portion; a female die for defining an outer peripheral portion of the hollow member, the female die being fitted in the annular base portion; and a mandrel having a plurality of forming protrusions, the mandrel being inserted and held in a mandrel holding slit formed in a center of the bridge portion in a fore-and-aft direction. The mandrel includes a mandrel main portion divided into a plurality of divided members and a plurality of rigid pins each arranged in a fore-and-aft direction of the mandrel main portion, and wherein the rigid pins are pinched by and between the divided members of the mandrel main portion with tip portions of the rigid pins protruding from an front end of the mandrel main portion, whereby the tip portions constitute the forming protrusions.

Abstract: A tip assembly includes a tip having a nose portion. The tip defines a central bore. The nose portion includes a lip portion and defines a counterbore. The counterbore has a counterbore side wall and a seat surface. The counterbore is contiguous with the central bore. An insert member includes an inner surface, an outer surface and a side wall. The inner surface is opposite the outer surface. The side wall interconnects the inner surface and the outer surface. The insert defines a central aperture that extends from the inner surface to the outer surface. The insert is disposed within the counterbore such that the central aperture is substantially concentric with the central bore of the tip. The lip portion of the tip engages the outer surface of the insert.

Abstract: An extruder die head comprises an internal cylindrical mandrel and a shell, which encloses said mandrel concentrically. Between said mandrel and shell an annular channel is formed that empties into the die slit. A polymer melt is fed through a line to the annular channel. To prevent the polymer melt in the area of the start of the annular channel from penetrating into a slit that forms between the mandrel and the shell due to heat expansion, there is between both mandrel and shell a ring with such a coefficient of thermal expansion that when heated up due to the polymer melt said ring seals the slit between the shell and the mandrel.

Abstract: To provide manufacturing method for a double tube having a hole formed therein and a mold for implementing such method, which reduce the time required for manufacturing, do not leave shavings in the gap between the outer tube and the inner tube, and offer highly accurate hole positioning. The manufacturing method for a double tube having a hole formed therein pertaining to the present invention uses a mold in which a punch is located in at least one of the split mold halves that form the outer circumferential surface, an indentation is formed by drawing the punch into the mold, and fluid pressure is applied between the outer tube and the inner tube of the double tube located within the mold to form a hole in the circumferential wall of the outer tube via such indentation. Furthermore, the punch is placed in the mold in a watertight fashion.

Abstract: The present invention provides an apparatus and method for manufacturing polymeric thin-walled tubular members, which are well-suited for use as vascular grafts. The apparatus of the present invention enables extrusion of a tubular member having an extremely thin wall thickness so as to facilitate passage through tortuous vascular passageways. The apparatus achieves uniform wall thickness in a tubular member by establishing and maintaining axial alignment of a ram having a concentrically disposed guide rod therein with a die supported in concentric relation to the guide rod.

Abstract: An extruder die head, preferably a blown film head, comprises an internal cylindrical mandrel and a jacket, which envelops concentrically said mandrel. Between said mandrel and jacket an annular channel is formed that empties into a die slit. The invention also comprises at least one line, which empties into the annular channel in the area opposite the die slit and which feeds a melt. To prevent a slit between the central mandrel and the jacket, enclosing said mandrel, where the polymer melt could accumulate and deposit, the mandrel is made as one piece with a flange-shaped foot. The jacket rests with its bottom face sealingly on the annular surface of the flange-shaped foot and is connected, for example fastened, to the same. The annular channel extends from the peripheral surface of the mandrel to the flange-shaped foot up to and into the transition region. The line, feeding in a melt, empties into this transition region.

Abstract: An extrusion die for extruding biodegradable material, the extrusion die including: a mandrel; an outer member positioned near the mandrel; an extrusion orifice between the mandrel and the outer member; a member in communication with at least one defining member of the extrusion orifice, wherein the member is capable of producing relative movement between outer member and the mandrel, wherein the relative movement has a component transverse to an extrusion direction of biodegradable material through the extrusion orifice; a flow control device which controls flow of biodegradable material through the extrusion die; and a positioning device which positions the outer member and the mandrel relative to each other.

Abstract: An improved method and apparatus is provided for extruding ePTFE tube for use in medical applications. A tube of PTFE is extruded, preferably in an extrusion process, using counter-rotated die components. The die component is maintained at a constant temperature during processing. The resulting green tube has enhanced fibrous state formation in a direction perpendicular to the direction of extrusion. The PTFE green tube is then subjected to secondary operations such as stretching and expansion to yield medical product. The ePTFE tube structure is defined by nodes interconnected by elongate fibrils. Both the nodes and fibrils are substantially randomly tilted with respect to the longitudinal axis of the tube. This particular structure yields a tube which exhibits a high degree of radial tear strength useful in medical applications.

Abstract: An extrusion head for use in the paste extrusion of lubricated PTFE fine powder, the extrusion head comprising an external die having an inlet, a chamber, and an outlet, a tip positioned in the chamber of the die, the tip having a circumferential ridge formed therein that extends into the chamber, the chamber having a shape complementary to the ridge so as to form a space between the external die and the tip to allow lubricated PTFE fine powder to pass therethrough, and a mandrel which extends through the external die and supports the tip in the chamber.

Abstract: A honeycomb structure molding apparatus 1 having a spinneret 4 provided with a back pore part 3 for introducing a molding material and a slit part 2 for extruding the molding material, and a press plate 5 for fixing the spinneret 4, in which the spinneret 4 comprises an inner side part 11 and an outer peripheral part 12, the inner side part 11 is protruded to the downstream side to form a level difference part 15 between the inner side part 11 and the outer peripheral part 15, the press plate 5 is opened opposing the inner side part 12 of the spinneret 4 and presses the downstream side of the outer peripheral part 12 of the spinneret 4 through a gap part 7, and there is provided a gap adjusting means 130 capable of changing width of the gap of the gap part 7.

Abstract: A die apparatus, a method of using the die apparatus to produce co-extruded polymeric articles, and co-extruded polymeric articles produced using the die apparatus and method are disclosed. The die apparatus includes a hollow vane configured to extrude a material into a chamber within the die, thereby producing a co-extruded web. The co-extruded web has a plurality of distinct, discontinuous phases in the cross-web direction, the phases having a uniform width as shown by a coefficient of variation of less than 8 percent for any three consecutive phases. The phases are substantially continuous down-web and are surrounded by a matrix having two or more layers.

Abstract: A honeycomb structure molding apparatus being free from defects in cells and having a higher strength with thin partition walls forming the cells and having a small cell density; and the apparatus having a plate-like spinneret provided with back pores for introducing a molding material and slits for extruding the molding material, and a press plate for fixing spinneret, the spinneret comprising an inner side and outer peripheral parts, the inner side part protruding downstream to form a level difference part therebetween, the press plate opening opposing the inner side part of the spinneret and presses the outer peripheral part of the spinneret downstream, and width W (mm) of slits, length L 1 (mm) of slits of the inner side part and length L 2 (mm) of slits of the outer peripheral part satisfying following two formulas:

Abstract: Provided is a blown molding die to obtain a film having excellent properties and good appearance in blown film forming of a thermoplastic resin manifesting anisotropy in molten state. The blow molding die has a simple structure compared with a conventional spider die, and can be produced easily and at low cost.

Abstract: The present invention is directed to a method and apparatus for using a spiral flow assembly in a polymer extrusion process to make small diameter tubing for such items as wires, cables, and tubing. The invention comprises a mandrel inside of a housing, the mandrel having spiral grooves located on its external surface. A polymer melt is introduced into the housing through an ingress port and flows into and through the spiral grooves on the outside surface of the mandrel, in what is called “groove flow” or “channel flow.” As the polymer melt flows through the grooves or channels, the housing and mandrel begin to separate by either having the housing taper outwardly, becoming gradually larger in diameter along the axial distance of the mandrel or having the mandrel begin to taper inwardly, becoming gradually smaller in diameter along the axial distance of the mandrel.

Abstract: An extruder die head, preferably a blown film head, has an internal cylindrical mandrel and a cylindrical jacket, which envelops concentrically the mandrel. Between the mandrel and jacket an annular channel is formed that empties into a die slit. At least one melt-supplying line empties into the annular channel in the area opposite the die slit. To avoid slits between the central mandrel and the jacket, enveloping the mandrel, where the polymer melt can accumulate and deposit, the mandrel is made as one piece with a flange-like foot and is provided in the area, adjacent to the foot, with at least one borehole, which feeds in the melt. On the mandrel adjacent to the foot is shrunk a ring, which seals the slit between both the mandrel and jacket. The cylindrical jacket is mounted above and connected sealingly to the shrunk-on ring to form the annular channel.

Abstract: A honeycomb structure molding die that can mold a thin-walled honeycomb structure without degrading the moldability has been provided. A honeycomb structure molding die 8 comprises at least supply holes 81 to supply materials and slit grooves 82 that are communicated with the supply holes 81 and mold the materials into a honeycomb shape, wherein the groove width of the slit grooves 82 is not more than 100 &mgr;m and simultaneously, recesses 41 and protrusions 42 that extend in the direction in which the materials are extruded are provided on a pair of opposing side surfaces 820 of the slit grooves 82.

Abstract: An annular die designed to produce polymer foam using only one or more ambient gasses as a blowing agent includes an exiting channel with an exit having a cross-sectional area between about two and about ten times that of a smallest point within the exit channel. The section of the die from the smallest point to the exit is thermally isolated from the rest of the die, and the temperature thereof is independently controlled. In addition, the interior surface of the exit channel is coated with a friction-reducing coating.

Abstract: A die is mounted within an extrusion die assembly to pivot with respect to the die body and thereby adjust the concentric position of the die with respect to the tip and the product to be coated. Spherical surfaces are formed in an intermediate support module to engage mating surfaces formed on the die holder. The spherical surface surround the die holder and are clamped together by screws which are limited in tightening, to avoid binding the pivotal movement between the spherical surfaces and the die holder.

Abstract: The present invention provides a hollow ceramic monolithic support that has high isostatic strength, a method of manufacturing the hollow ceramic monolithic support at low cost, and a molding die therefor.

Abstract: A laser groove machining method for forming bottomed grooves in a surface of a workpiece using a laser, wherein an emitting position of a laser beam which is to be emitted onto the workpiece is shifted relatively along groove forming positions at a high speed of 150 mm/min. or faster. Thus, melted portions which are melted by the laser beam can easily be separated, cooled and removed by shifting the laser beam emitting position at high speed. In addition, water may be jetted to the workpiece so as to form a pillar of water so that the laser beam is emitted through the interior of the pillar of water so formed.

Abstract: The invention relates to an extrusion die assembly having a balanced flow path in which the die and tip modules cooperate to form an extended exit channel which communicates with an extrusion channel. The die is rotatably mounted on the die holder and the tip module is rotatably mounted within the axial bore. Each of the rotatably mounted components is independently driven by a motor. The motors are controlled to provide an infinite variation in relative rotational motion between the rotating components.

Abstract: The present invention provides a portion of a die assembly (20) for use in the extrusion of foamed polystyrene. The die assembly includes a first plate (21), a second plate (22), and an insert (23). The first plate has an upstream face (24), a downstream face (25), and a first opening (26) extending between the two first plate faces. The walls (28) of this opening are divergent in a downstream direction. The second plate has an upstream face (29) arranged to abut the first plate downstream face, a downstream face (30), and a second opening (31) extending between the second plate faces and communicating with the first opening. The second opening is bounded by non-divergent walls (32). The insert has a forward marginal end portion mounted on the first plate in the first opening, and has a rearward marginal end portion arranged in the second opening.

Abstract: A method of extruding plastic material in multi-layer form includes: providing an extrusion die having a first body member and a second body member surrounding the first body member and forming an annular passage therebetween which communicates with an annular extrusion orifice, the body members having a series of helical grooves extending around the die and each commencing at a separate location, the separate locations being spaced around a lower portion of the first body member. A single encapsulating unit provides a flow of encapsulated plastic material comprising a first plastic material surrounded by a second plastic material at an outlet thereof. The first body member having a series of cross-holes extending from the encapsulating unit output and each communicating with a respective separate location.

Abstract: A coating method of coating an outer circumferential surface of a cylindrical base with a coater having a supply port, a coating solution chamber, and a slit communicating with the coating solution chamber, the slit being provided around an inner circumferential surface of the coater, comprisse steps of: feeding a coating solution from the supply port to the coating solution chamber so that the coating solution is discharged to the slit; adjusting an absolute pressure P in the coating solution chamber so as to satisfy the following formula: 3×104≦P≦3×106 (mmH2O) and relatively moving the cylindrical base through a hole formed by the inner circumferential surface of the coater so that an outer circumferential surface of the cylindrical base is uniformely coated with the coating solution flowing out from the slit.

Abstract: The invention provides a spinnerette assembly for forming hollow fibers. The spinnerette assembly contains an extrusion orifice and a fiber-forming material passage in communication with the extrusion orifice. A hollow needle extends through the extrusion orifice in a concentric manner to define an annular passage surrounding the needle. The fiber-forming material passage includes a fiber-forming material inlet port extending from a surface of the spinnerette assembly to an interior of the assembly and a transverse passage extending from the fiber-forming material port to the annular passage surrounding the needle. A bore forming fluid passage communicates with the interior of the needle.

Abstract: The invention provides a spinnerette assembly for forming multicomponenthollow fibers of the sheath/core type. The spinnerette assembly contains an extrusion orifice and a core forming material passage in communication with the extrusion orifice. A hollow needle extends through the extrusion orifice in a concentric manner to define an annular passage surrounding the needle. The core forming material passage includes a core forming material inlet port extending from a surface of the spinnerette assembly to an interior of the assembly and a transverse passage extending from the core forming material port to the annular passage surrounding the needle. A bore forming fluid passage communicates with the interior of the needle. The spinnerette assembly contains at least one sheath forming material passage also in communication with the extrusion orifice.