Provided is a method for producing a resin molded article, capable of reducing deterioration of resin during melt extrusion. The method includes passing a resin fed from a hopper for resin through a molding machine provided with the hopper, an extruder, and a pressure control device in this order, to produce a resin molded article, the resin pressure between a tip of the extruder and an inlet port for resin of the pressure control device being 15.0 MPa or lower.

In a method and a device for producing a powder coating melt, firstly a first powder coating melt is produced from a powder coating premix by means of a screw machine. Powder coating particles are supplied to the first powder coating melt. Then a second powder coating melt is produced by mixing the first powder coating melt and the powder coating particles by means of the screw machine. This allows a simple, gentle and efficient recycling of powder coating particles, in particular of so-called off-spec powder coating particles.

A screw extruder for extruding a kneaded material, includes: a pair of screws; a casing that houses the pair of screws and includes a supply port; and a roller-die. Each of the screws includes a shaft portion, and a spiral flight portion. The flight portion is formed into a shape in which a radial distance between the surface of the shaft portion and a tip of the flight portion decreases gradually toward a downstream end in an extrusion direction of a kneaded material. The casing has a tapered shape. Within a range between a downstream end of the supply port and a downstream end of the flight portion, a clearance between a top portion of the flight portion and an inner wall surface of the casing at the downstream end of the supply port is larger than a clearance at any other part.

A screw extruder which extrudes a kneaded material includes a screw having a helical flight provided on an outer peripheral surface of a shaft portion thereof, and a chamber housing the screw. In the screw extruder, a flight thickening portion is provided at a part which is a tip portion of the flight and is on the reverse side of a rotation direction of the flight.

A twin screw extruder (10) for producing a fiber-reinforced resin composition, which is obtained by charging the extruder with a thermoplastic resin and reinforcing fibers in roving form and the reinforcing fibers being fibrillated/cut and being dispersed/kneaded into the thermoplastic resin, comprises: a plate-shaped blade (15), which protrudes from the inner surface of a cylinder (11) and faces a screw (20) and the longitudinal direction of which faces the axial direction of the cylinder; and a height adjustment means (16) for adjusting the gap between the blade (15) and the screw (20).

A hopper charged with a powder material, a screw arranged below the hopper and exposed at a supply port formed at the bottom of the hopper, and a rolling element in contact with the screw at the supply port are provided. The rolling element is larger than a space between end portions of the supply port and a screw groove of the screw.

A process for producing a substantially dry product, according to various embodiments, may include receiving wet grain at a first screw The process includes receiving the wet grain at a second screw from the first screw. The process includes compressing the wet grain between the first screw and the second screw and dehydrating the wet grain when the wet grain is located within at least one zone of the first screw and the second screw to cause a physical property change to the wet grain.

An installation for producing a polymer melt for a porous film, in particular for a membrane film, comprises a planetary roller extruder. Said extruder is used to produce a flowable polymer melt from thermoplastics. The planetary roller extruder has a filling opening and a discharge side for delivering the polymer melt. A melt pump is further provided. The discharge side of the planetary roller extruder is connected to a downstream inlet side of the melt pump for further conveying the polymer melt. The connection is in the form of a pressure channel shielded from the ambient atmosphere or a pressure line shielded from the ambient atmosphere. The planetary roller extruder and the melt pump are designed and/or can be driven in such a manner that the polymer melt is applied or can be transferred under pressure at the melt pump on the inlet side.

A continuous mixer includes a barrel with a hollow interior, and a pair of mixing rotors housed in the barrel and that rotate in mutually different directions, each mixing rotor including a mixing portion with plural mixing flights formed about an axial center of the mixing rotor and projecting radially outward. The mixing rotors have a center distance therebetween smaller than a rotation outer diameter of each of the respective mixing flights. An inter-rotor clearance, which is the smallest clearance between the mixing portions at each rotation phase of the mixing rotors in a cross section perpendicular to axial directions of the both mixing rotors, has a dimension allowing an extensional flow to be generated in a material passing through the inter-rotor clearance. The continuous mixer can reliably and efficiently mix a material having a large viscosity difference between a dispersed phase and a matrix phase.

A screw extruder with rollers includes a screw which extrudes a material; a casing which houses the screw and which is provided with a charging port for the material; and a pair of an upper roller and a lower roller which are arranged in front of the casing and mold the material extruded by the screw into a sheet, in which one of the upper roller and the lower roller has both end portions in an axial direction, and a main body portion between the both end portions, and a cross-section of the main body portion perpendicular to the axial direction has an oval shape.