A rotating member of the present disclosure mainly includes ceramics and includes a first through-hole into which a shaft is inserted and a second through-hole into which a key protruding from an outer peripheral surface of the shaft or a solid lubricant in direct or indirect sliding contact with the outer peripheral surface of the shaft is inserted. The second through-hole is a polygonal shape if viewed in an axial direction of the first through-hole and includes a notch part extending along the axial direction at at least one corner.

An extruder screw includes a screw main body, conveyance portions, barrier portions, and paths. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in an opposite direction to a conveyance direction of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position on an upstream side in the conveyance direction in the conveyance portions in which the entrance is opened.

A co-rotating self-cleaning two-screw extruder with a gradual number of threads and through self-cleaning function, and a processing method using the same, are disclosed. The screw assembly in the extruder includes a first screw (3) and a second screw (4) that co-rotate at the same speed in engagement; the first screw (3) includes a first single threaded element, a first transition element, a multiple threaded element, a second transition element and a second single threaded element that are connected in sequence; and the second screw (4) includes a first single threaded element, a third transition element, a multiple threaded element, a fourth transition element and a second single threaded element that are connected in sequence. The materials are transferred by rotation of the first (3) and second screws (4), and get their respective compositions mixed based on the structure of a gradual number of threads; with the flow passage expanded, contracted and re-expanded in shape in sequence, the materials undergo the single-to-multiple threaded, multiple-to-single threaded and again single-to-multiple threaded chaotic mixing in sequence; and the first and second screws achieve the self-cleaning effect by wiping each other.

A co-rotating self-cleaning two-screw extruder with a gradual number of threads and through self-cleaning function, and a processing method using the same, are disclosed. The screw assembly in the extruder includes a first screw (3) and a second screw (4) that co-rotate at the same speed in engagement; the first screw (3) includes a first single threaded element, a first transition element, a multiple threaded element, a second transition element and a second single threaded element that are connected in sequence; and the second screw (4) includes a first single threaded element, a third transition element, a multiple threaded element, a fourth transition element and a second single threaded element that are connected in sequence. The materials are transferred by rotation of the first (3) and second screws (4), and get their respective compositions mixed based on the structure of a gradual number of threads; with the flow passage expanded, contracted and re-expanded in shape in sequence, the materials undergo the single-to-multiple threaded, multiple-to-single threaded and again single-to-multiple threaded chaotic mixing in sequence; and the first and second screws achieve the self-cleaning effect by wiping each other.

A multiple screw extruder (50) combines application of vacuum to a vacuum vent (62) positioned between material feed locations (70, 72) of the extruder and use of specially configured extruder screws (58) to extract gases, primarily air, out of the extruder to densify the materials introduced into it and to extract unwanted fluid from material introduced for mixture with molten polymeric material flowing through the extruder. The multiple screw extruder is operationally versatile in that it is capable of carrying out the material densification and fluid extraction processes either separately or simultaneously. Implementation of the disclosed vacuum feed technology provides an increase in rate of extrudate throughput as compared with that achievable by implementation of atmospheric venting (16) in a conventionally configured extruder (10a, 10b).

An extruder screw includes a screw main body, conveyance portions, barrier portions, and paths. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in an opposite direction to a conveyance direction of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position on an upstream side in the conveyance direction in the conveyance portions in which the entrance is opened.

An extruder screw includes a screw main body, conveyance portions, barrier portions, and paths. The raw materials, the conveyance of which is limited by the barrier portions, flow in from the entrance. The raw materials flowing in from the entrance flow through the paths in an opposite direction to a conveyance direction of the conveyance portions. The exit is opened in the outer circumferential surface of the screw main body at a position on an upstream side in the conveyance direction in the conveyance portions in which the entrance is opened.

The present disclosure relates to a process for preparing granules from an input material or a powder material. The process comprises feeding the input material for granulation in the processor using one or more powder feeders, introducing steam as a granulation activating agent in the processor, granulating the input material in presence of the steam to form granules, and optionally collecting the granules from a discharge zone of the processor, wherein feed rate of the steam into the processor is determined based on feed rate of the input material into the processor. A co-rotating twin-screw processor for preparing granules is also disclosed.

A co-rotating twin screw processor for preparing dry granules including an input zone having one or more powder feeders for feeding an input material into the processor, a steam feeder configured to introduce steam as a granulation activating agent in to the processor, a granulation zone for granulating the input material in the presence of steam to form granules, a controller configured to control operation and feed rate of at least one of the powder feeder or the steam feeder such that 2.5 to 5 percent w/w of the steam with respect to the input material is available for granulation, and a discharge zone haring a non-extruding opening for collecting dry granules.

A method and a device for admixing additives into a polymer melt made of non-extracted polyamide 6 are disclosed. The polymer melt is combined in a highly concentrated form with an additional melt flow without additives and mixed therewith. Additionally, a part of the melt is branched off from a main melt flow (3), wherein the sub-melt flow (4) is transported into a dispersing device (5) and is supplied and mixed with one or more additives (12). The side-melt flow (4) with additives is then returned into the main melt flow (3), mixed with the main melt flow, and subsequently supplied for further processing.