An extruder having an extruder crosshead, a die, and a die retaining assembly. The extruder crosshead has an annular major surface while the die has a first die surface facing and conformal to that major surface. The die also has a second die surface opposed to the first die surface. The die-retaining assembly is attached to the extruder crosshead, evenly and variably pressing the second die surface with controlled pressure such that the substantially opposing first die surface is pressed into the major surface of the extruder crosshead. The die-retaining also includes movable elements which abut the die in order to move the die. The die-retaining assembly can be used to evenly reduce the pressure exerted by over the second die surface so that the position adjustment elements can be used to more easily adjust the position of the die.

A method and an apparatus manufactures and tests workpieces. The apparatus is mountable on or includes a system for mixing or melting materials. The apparatus includes application units and a replacement system that is designed to automatically replace application units in respect of the position or function thereof.

A mixer apparatus for the treatment of a polymer material to generate the Maxwell effect therein, at a rotor-stator interface in a mixer. The mixer comprises an alternating series of stators and rotors arranged along an elongated driveshaft supported within an elongated housing. The stators and rotors each having at least one helically arranged channel extending from an upstream end of the stator to an end location near the downstream end of that stator, those helically arranged channels preferably are arranged on the surface of the bore extending through the stator. A further generally radially directed channel from the end location of that helically arranged channel to a peripheral surface discharge at the downstream end of that stator is arranged to supply the polymer passing therethrough, to the upstream end of an adjacent rotor having a plurality of helically directed channels arranged on its outer periphery, those channels being inclined radially outwardly and of tapered dimension from an upstream end to a widened downstream end.

A method for producing a densified material includes: obtaining a film including at least one first layer of plastic material and one second layer with a composition distinct from the first layer, the first layer having a first melting temperature, or obtaining pieces of such a film; compressing the obtained film or the obtained pieces of film through at least one die of at least one extruder, and obtaining a profile of densified material, the extruder including at least one rotary endless screw pushing the obtained film or pieces of film along a screw axis; and optionally cutting the profile in order to obtain granules of densified material, the compression step being carried out at a maximum compression temperature for the obtained film or pieces of film, the maximum compression temperature being less than the first melting temperature. Also disclosed are installation and use of the densified material.

Extruded films comprising ethylene vinyl alcohol copolymer (EVOH) with substantially no blow holes therein, are formed by using a pellet feed to the extruder wherein 90-100 wt. % of the pellets pass through an ASTM size 5 sieve and 0-10 wt. % of the pellets are finer than a number 10 mesh (ASTM Sieve size). Uniform feeding to and through the extruder with a lack of bridging of the EVOH pellet feed have been observed.

On a rotary screen filtering device for medium to high-viscosity fluids, which comprises a rotary screen mounted for rotation in a housing, which screen has at least one screen element through which fluid can flow, the rotary screen, in the region of its sealing faces and the intermediate plates are fabricated or machined together so that they are of identical height. A gap width compensation layer is then inserted between the inlet plate and the intermediate plate and/or between the outlet plate and the intermediate plate. The package of plates is then pretensioned by means of screw bolts in such a manner that all the plates lie firmly against one another up to a maximum permissible operating pressure. Lubrication gaps of defined width are created between the sealing faces and the opposing inner faces of the inlet and outlet plates.

Provided is a method for producing a resin composition from which can be formed a molded body having excellent tensile elongation and/or rigidity, and more preferably a molded body which stably achieves both high tensile elongation and high rigidity. An aspect of the present invention provides a method for producing a resin composition which contains a first component and a second component, said method comprising a kneading step for kneading the first component and the second component via an extruder provided with a kneading zone that includes a plurality of narrow gap zones in which the gap between a cylinder inner wall and a screw is not more than 2 mm.

An object of the present invention is to provide a method for producing water absorbent resin powder in which permeability potential (SFC) is improved while a water absorbing rate (FSR) is being kept. The method is a method for producing water absorbent polyacrylic acid (salt) resin powder including the steps of: (i) polymerizing an acrylic acid (salt) monomer aqueous solution; (ii) during or after the step of (i), performing gel grinding of a hydrogel crosslinked polymer obtained by the polymerization, wherein the hydrogel crosslinked polymer has resin solid content of 10 wt % to 80 wt %, and the gel grinding is carried out with gel grinding energy (GGE) of 18 [J/g] to 60 [J/g]; (iii) drying a particulate hydrogel crosslinked polymer obtained by the gel grinding, wherein the drying is performed at 150 C. to 250 C.; and (iv) carrying out a surface treatment to the particulate hydrogel crosslinked polymer thus dried.

Provided is a water absorbent resin that is useful to sanitary materials such as a disposable diaper, a sanitary napkin, and a blood absorbent for medical use each having a higher liquid permeability and a higher water absorbing speed. Further provided is a water absorbent resin powder that is useful to sanitary materials such as a disposable diaper, a sanitary napkin, and a blood absorbent for medical use each having increased in absorbency of a liquid and in heat retaining property. A gel grinding device to be used to produce a water absorbent resin, includes: a screw; a feed opening; an extrusion opening; a porous plate; and a barrel, the barrel including a return preventing member provided on an inner surface thereof, and the return preventing member satisfying at least one of specific parameters.

Provided is a water absorbent resin that is useful to sanitary materials such as a disposable diaper, a sanitary napkin, and a blood absorbent for medical use each having a higher liquid permeability and a higher water absorbing speed. Further provided is a water absorbent resin powder that is useful to sanitary materials such as a disposable diaper, a sanitary napkin, and a blood absorbent for medical use each having increased in absorbency of a liquid and in heat retaining property. A gel grinding device to be used to produce a water absorbent resin, includes: a screw; a feed opening; an extrusion opening; a porous plate; and a barrel, the barrel including a return preventing member provided on an inner surface thereof, and the return preventing member satisfying at least one of specific parameters.