Abstract: The problems caused by chemical and thermal shrinkage of hard roll covers, are reduced by the inclusion of one or more intermediate compressive layers between the metal roll and the outer cover, or "topstock". A compressive layer has the properties of being rigid enough to allow the cover to be applied to the roll, and compressible enough to buffer and absorb the stresses which occur as the cover is shrinking during processing.In one embodiment, the intermediate compressive layer comprises a three dimensional fabric that is filled preferably with a thermoset resin system which cures at lower temperature than cover. In a second embodiment, the precise amount of shrinkage in the roll can be predetermined to a high enough degree of accuracy so that a depth for the fabric layer can be used to compensate for the amount of shrinkage, thereby eliminating the need for filling. In a third embodiment, the compressive layer is comprised of a wax material.

Abstract: A pipeline for introduction of solids into a treatment vessel consists of a plurality of pipe elements made up of two or three pipe sections having their respective axes running at an obtuse angle to each another, with a rotary connection in the vertical plane between the pipe elements. One end of a pipe element extends into the rotary connection and the adjoining pipe element, which is here widened out to form a funnel.