Abstract: A screw extruder comprises a barrel (10) having a chamber (12) in which a screw (14) is mounted for rotation about an axis A. Sets of pins (22) project from the barrel into annular zones (24), (25) of the chamber (12), interrupting flights (26), (28), (30), (32) of the screw. The flights at either side of the, or each, annular zone (24) are displaced angularly relative to one another so that at either side of each annular zone (24) the flights are staggered. End portions of adjacent flights at either side of each annular zone (24) overlap. Material processed may have less temperature variation and improved homogeneity compared with material processed by previously known extruders.

Abstract: A cutter is provided for cutting rope into fibers of the same or varying lengths. A plurality of blades are provided having cutting edges arcuately arranged and facing either inwardly or outwardly. Rope is fed against the cutting edges and through the spaces between them. The cutting blades are parallel to each other and are obliquely arranged with respect to a plane passing through all of the cutter blades. In a preferred embodiment, the blades are equally spaced from each other so that the resulting cut products comprises a multiplicity of cut fibers which all have approximately the same length. Also disclosed is a novel reel structure comprising a pair of superposed blade support rings with a coaxial hub member extending therebetween and providing support therefor. A plurality of spokes extend radially from the hub and are connected to at least one of the blade support rings.

Abstract: A spacer retaining element, which may be a fuel rod or water-containing rod, is provided with axially-spaced lugs, each adapted to be received in a slot in a fuel element spacer of a nuclear fuel assembly. When assembled, the lugs maintain proper axial spacing between the individual spacers and the lug-slot arrangement prevents the rod from rotating. Moreover, because the slot in the spacer can receive the lug from only one direction, the arrangement prevents the spacer from being inserted into the assembly upside down.

Abstract: Means are provided to minimize crud buildup at the interface between the tie plate and end plug in a nuclear fuel bundle. The means may comprise serrations in the end plug and/or serrations in the surface of the tie plate which serrations provide a flow of coolant through the end plug receptacles. A bleed hole extending into the interior of the tie plate may be provided to provide coolant circulation through any blind holes that may be in a tie plate.

Abstract: A spacer for positioning at least the four corner fuel rods in a tubular flow channel of a nuclear reactor is disclosed. The spacer comprises a support member having four side bands interconnected by four corner bands to form a unitary structure. Each of the side bands has a L-shaped lobe adjacent each of its ends with one leg of each lobe extending to the adjacent end of its side band. Each of the corner bands is narrower than the side bands and is offset so as to be spaced from the lobe. One leg of each lobe is positioned to engage the tubular flow channel to maintain proper spacing between the flow channel and the adjacent corner fuel rod and to improve the thermal-hydraulic performance of the spacer.

Abstract: The invention relates to an improved accelerator for gypsum board manufacture, the accelerator containing a ground mixture of gypsum and a long chain fatty carboxylic acid, e.g. stearic acid, or a salt thereof, to the manufacture of the accelerator, and to its use in gypsum board production. The accelerator is less liable to deterioration on storage than conventional gypsum accelerators, and its use yields gypsum board of improved properties.