Abstract: A process for producing a web fleece of thermoplastic polymer filaments. Filaments of thermoplastic polymer are spun from a spinneret to form a curtain passing through a cooling chamber and a stretching channel. The volume rate of flow of the thermoplastic polymer from the spinneret, the volume rate of flow of air, the velocity of the air and the temperature of the air in the cooling chamber and stretching channel are so controlled that individual filaments of the curtain have filament diameters less than .mu.m and a degree of crystallinity less than 45%. The filaments of the curtain are collected on a continuously moving sieve belt in a mat whose crossing points fuse together. The mat is heated to a stretching temperature of 80.degree. to 150.degree. C. and stretched axially by 100 to 400%. The biaxially stretched mat is heated to a temperature above that of the stretching temperature to thermofix the web.

Abstract: An apparatus for making a plastic filament web has in a vertical stack starting from the top an extruder releasably mounted on a platform, connected to a spinneret, and supplying molten plastic thereto for formation of plastic streams, a blowing unit directly beneath the spinneret cooling the streams and forming them into plastic filaments, a stretching gap directly beneath the blowing unit stretching the plastic filaments, a diffuser shaft directly beneath the stretching gap looping the stretched plastic filaments, and a foraminous conveyor directly beneath the diffuser shape receiving the looped and stretched filaments as a fleece which it transports horizontally out of the apparatus. A lowermost housing containing the conveyor sits directly on a stationary support surface and has an upper surface. An uppermost housing spaced above the lowermost housing supporting the extruder platform contains at least the spinneret and has a lower surface.

Abstract: A foil-blowing apparatus has its external cooling nozzles vertically and/or radially adjustable relative to the transition region between the neck of the thermoplastic tube and the blown foil balloon to enable thickness errors to be eliminated.

Abstract: A foil blowing head for a thermoplastic synthetic resin tube has a primary air guide juxtaposed with the blowing head portion defining the internal primary air outlet, also formed with passages for the secondary air and is axially shiftable on the discharge tube from which air is led from the foil balloon.

Abstract: A melt-blowing head is used to produce long thermoplastic filaments which are collected on a sieve belt and form crossing welds at cross-over points. The resulting mat may be calendered and is composed of filaments having a diameter of less than 100 .mu.m and a degree of crystallinity which is less than 45%. The mat is heated to a stretching temperature of 80 to 150.degree. C. and is then biaxially stretched by 100 to 400% before being thermally fixed at a higher temperature. The result is a nonwoven web which can have a greater strength for a given area weight or a reduced area weight for a given strength than earlier systems.

Abstract: An apparatus for blow extruding a tubular plastic foil has a nozzle having an upwardly open annular mouth generally centered on a longitudinal axis for upwardly extruding a tubular plastic strand and an inner tube extending upward from the nozzle within the mouth thereof, having an upper end spaced axially from the mouth, and formed between the upper end and the mouth with at least one radially throughgoing hole. A stabilizer head carried on the inner-tube upper end is formed with passages having inner ends opening into the inner tube at the upper end thereof and outwardly directed outer ends. An outer tube surrounding the inner tube defines an inner longitudinal passage therewith, extends upward from the nozzle within the mouth thereof, and has an upper end above the hole and below the inner-tube upper end.

Abstract: Nonwoven spun-bond is produced by a stationary pressure apparatus in which the shaft below the spinneret has an inlet section followed by the downwardly converging intermediate section, a drawing section and a diffuser opening above the collecting belt through which air is drawn by a suction device. The process air velocity profile has an intersection point with the drawing value at the intermediate section and the distance between the intersection point and the spinneret is smaller than the distance between the intersection point and the bottom end of the drawing section.

Abstract: In a foil blowing apparatus, the distribution of singularity in the flattened foil tube over the length of a roll in which the tube is coiled are distributed by a fold shifting device above the squeezing rollers at the top of the foil blowing unit. The fold shifting device has three sets of pivotal planes each formed by a deflecting roller and a turning bar and oriented so that the maximum angle between each approaching stretch of the flattened tube and a perpendicular to the turning bar is 30.degree. and the maximum angle of each departing stretch and the perpendicular to the turning bar is 30.degree..

Abstract: A collecting belt for the web of a spun bond or melt blown apparatus has one deflecting roller with fixed bearings and another deflecting roller with floating bearings upon which pneumatic cylinders act to provide equal forces. Upon the pneumatic system a proportional controller in response to the belt position sensor superimposes control signals to compensate for deviations in belt orientation.

Abstract: A spun-bond apparatus can be operated with additional high-pressure jets at the outlet gap immediately above the collecting belt and below the intermediate passage connecting that gap with the cooling chamber to establish a higher velocity of the filaments which are collected in the nonwoven fabric on the belt.

Abstract: A spin blowing apparatus for producing spun fleece of thermoplastified synthetic resin provides that the spinneret plate and/or the fiber or filament blowing gap through which the blowing air/fiber mixture passes downwardly and/or the air flow resistance of the perforated belt upon which the fleece is collected can be varied in response to measured values of the specific weight and/or air permeability of the web to restore any deviation of the latter.

Abstract: A spun-filament nonwoven web is deposited on a sieve belt from a spinning head producing a curtain of thermoplastic filaments which traverse a cooling chamber by drawing the filaments in a drawing nozzle separate from the cooling chamber and passing the filaments through a delivery unit and in the form of a jet pump, air flow through which is controlled at least in part by a suction blower below that sieve belt.

Abstract: To simplify the cleaning and maintenance of a meltblowing head, the lips defining with the spinneret the flowing slits adjusting the row of orifices can be swung away from the spinneret on respective lip guides pivotally connected to respective setback bars. The setback bars can be adjusted and locked in place with respect to the blowing housing and the lips can be adjusted and locked in place relative to the lip guides independently of the swinging action.

Abstract: An extrusion die for extruding a thermoplastified synthetic resin, e.g. for a foil-blowing head or a wide-slit nozzle can have its adjustable lip positioned to vary the thickness of the extruded strand by a driver acting on a rod engaging that lip and driven by a step-down transmission from a servomotor which may be a stepping motor.

Abstract: In a apparatus of making a nonwoven mat wherein a multiplicity of filaments are extruded in a row and a pair of jets of compressed gas are played symmetrically from nozzles upon the filaments as same are extruded to stretch the filaments and deposit same on a substrate the compressed gas is made to flow from a source along respective paths to the nozzles and each of the flows and paths is branched upstream of respective flow-equalizing stations. The speed of the respective flows is decreased and their pressures are increased with at least one diffuser. The flows are then baffled and united between the flow-equalizing station and the respective nozzles in a flow guide.

Abstract: An extruder-housing part for a double-worm extruder for the plastification of thermoplastic synthetic resin and plastic mixtures has two chambers for receiving the worms and forming a figure eight cavity. A wear-resistant material formed as a hard-phase layer is provided to line the chambers. The extruder-housing part is a one-piece seamless structure with an isotropic lattice of powder metallurgical origin with a hot isostatic pressing configuration.

Abstract: A foil-blowing head has a nozzle lip which is substantially cylindrical and of an axial length of at least several centimeters and a radial thickness of at least several millimeters. High-force servoeffectors which can be provided with stepping servomotors, speed-reduction transmissions and eccentric drivers, can act upon radial rods to deform the lip and adjust the gap width and the thickness of the foil which is produced to provide continuous thickness correction during foil blowing.

Abstract: A flow-rearrangement device between the annular extrusion gap of an extrusion head and the feed for the thermoplastified synthetic resin has two disks with registering grooves forming rearrangement ducts communicating axial inlet bores with axial outlet bores to effect a flow rearrangement of the thermoplastified synthetic resin which produces microtexturing of the finished product. The extrusion head may be a film or foil blowing head.

Abstract: Blown or flat-extruded plastic film having systematic plus or minus errors in thickness along the width of the film have a thickness profile measured and the measured profile is fed to a computer which controls the extruded film or tube from which the film is blown so that the foil thickness will be increased between regions of plus-thickness error or decreased in sense between regions of minus-thickness errors, or both alternatingly, so that the resulting coil is cylindrical with significant precision and without the need to move the blowing head or tube flattening device.

Abstract: A process for the production of a plastic foil of thermoplastic material as well as for winding this plastic foil into a coil. The produced plastic foil has systematic thickness errors with plus thickness errors and minus thickness errors. The coil is practically free of thickness errors summed during winding. In order to achieve this, the thickness-error profile of the produced plastic foil with its systematic plus thickness errors and/or minus thickness errors is measured prior to the winding of the coil. A number n of layers of the plastic foil produced with the systematic plus thickness errors and/or minus thickness errors is wound up to a coil. After that, approximately a number n of layers of the plastic foil with the inverse thickness-error profile is wound on the coil. This is periodically repeated, n layers of plastic foil with the thickness-error profile alternating with approximately n layers with inverse thickness-error profile, until in the end the adequately cylindrical coil is produced.