Abstract: An expansible duct seal construction for a batch mixer vessel with a cover clamped to the open end of the vessel wherein a flexible duct perimetrally surrounds the cover and the end portion of the vessel adjacent the cover, the duct being secured to the sides of the vessel and including an expansion fold around its perimeter secured to the cover in a manner to prevent the escape of vaporous material. A gas under pressure is provided in the duct to balance the pressure in the duct with the gaseous pressure in the vessel and inhibit the migration of material from the vessel in the preferred form of the invention.

Abstract: A barrel assembly for a twin screw mixer or similar device is especially designed for ready access to a replaceable split liquid tight barrel liner which is accurately held in seated position within a housing block by a minimum number of bolts or other detachable connectors. Housing blocks are formed with liner half receiving recesses defined by flat surfaces which include inwardly convergent side walls and a flat inner wall. The liner half is of complementary shape and projects slightly from the recess, when seated in the recess so that closing of the housing blocks engages abutting surfaces on the two liner halves to clamp these surfaces against each other during operation of the machine. The housing blocks are mounted upon the machine frame by brackets for swinging movement about horizontal axes, meshing pinion gears couple the housing blocks to each other so that the weight of one housing block is counterbalanced by the other during opening and closing movements.

Abstract: A continuous mixer or kneader, particularly for explosive, potentially explosive, and other critical materials, wherein longitudinally split barrel sections are maintained closed by a mechanism which is actuated to instantly split the barrel sections under emergency conditions to permit the material inside to be treated to prevent or inhibit ignition of the material. The machine includes an extruding die and a cutter, for cutting extruded strands to lengths, which is coupled to the mixer shaft in the barrel, and in addition includes mechanism for interrupting the cutting of strands when the barrel sections are split.