Abstract: The invention relates to a roller mill with two rollers, a grinding gap formed thereby and a material inlet shaft the end walls of which bear on their lower ends carrier plates with replaceable sintered metal wear parts. Each wear part is formed by a plurality of small sintered metal plates of small area which are set close against one another like a mosaic and are individually screwed onto the carrier plate so that in case of wear only those small sintered metal plates which are actually worn can be replaced simply, quickly and economically.

Abstract: A chemically modified and activated, hydroxyl-group-containing, natural or synthetic, polymeric solid body surface is disclosed, as well as a process for the activation of such solid body surfaces by means of organo-silanes and, if necessary, homo- or heterobifunctional reagent. The surfaces are used for the stable, simple and economical binding of proteins, nucleic acids, low-molecular ligands, cells, microorganisms and other biological materials, in biology, biotechnology and medicine.

Abstract: A bearing segment for a tiltable and rotatable sliding shoe comprises a base on which is supported a bearing pin having a radial ball and socket joint coupling the pin to the shoe. The ball and socket joint has an inner ring supported on the pin and an outer ring fixed to the shoe. The rings have confronting arcuate surfaces which permit limited relative spherical movement of the rings.

Abstract: The invention relates to a hydrodynamic bearing in which a pressure limiting valve is connected to the oil supply to a groove provided at the inlet zone of the bearing element. The oil pump thus can be of considerably smaller dimensions than heretofore, the energy consumption in operation is reduced, and the removal of heat is improved.

Abstract: A hydrostatic bearing the bearing surface of which contains several pressure pockets. A bore arranged symmetrically to the pressure pockets connects the latter with a pressure relief chamber and with a source of hydraulic pressure medium. A bearing such as this is characterized by its simple construction and by reliable hydraulic pressure relief for each bearing shoe.

Abstract: Fine-grained material adapted to be fired in a furnace is discharged from a preheater into a gas conduit extending from the furnace to the preheater and through which a stream of hot gases pass. The conduit is shaped to deflect the gas stream and concentrate it along one side of the conduit in the area of introduction of the material to the conduit. Below the area of introduction of material to the conduit fuel burners provide a heating zone through which the material falls. The concentration of the gas stream along one side of the conduit assures entrainment of the material in the gas stream and passage of the material again through the heating zone. Above the area of introduction of material to the conduit the latter is shaped to deconcentrate the gas stream and permit some of the material entrained therein again to fall downwardly through the heating zone, following which such material is reentrained in the gas stream.

Abstract: This invention relates to a hydrostatic bearing unit for rotating parts, and more especially to a radial bearing unit for heavy machine parts, such as drums, comprising a fixed base and a shoe which is mounted for limited gyration relative to the base and for hydraulic adjustment with respect to the rotating parts and which comprises a bearing surface fed with hydraulic carrier medium. The invention also relates to a hydrostatic bearing assembly comprising several such bearing units.

Abstract: Fine-grained material such as raw ground cement adapted to be fired in a rotary tube furnace is introduced to a vertical preheater and falls through a heating zone located at a level below the level at which the material enters the preheater. A stream of air enters the preheater at a level below the heating zone and passes upwardly at sufficient velocity to entrain the material that has passed through the heating zone, thereby causing such material to pass again through the heating zone. From the preheater the material is delivered to the furnace for final firing.

Abstract: Fine-grained material such as raw ground cement adapted to be fired in a rotary tube furnace is introduced to a vertical perheater and falls through a heating zone located at a level below the level at which the material enters the preheater. A stream of air enters the preheater at a level below the heating zone and passes upwardly at sufficient velocity to entrain the material that has passed through the heating zone, thereby causing such material to pass again through the heating zone. From the preheater the material is delivered to the furnace for final firing.