Abstract: A pressure sealing assembly for a swing tube-type concrete pump. The assembly provides a fluid-tight seal between the intake end of the swing tube and the ports of the pumping cylinders. Pressure faces are formed in the bearing assembly where the discharge end of the swing tube passes out of the concrete hopper, and a lubricating medium, such as grease, is positioned in this assembly adjacent the pressure face which is directed toward the intake end of the swing tube. Pressure is selectively supplied to the lubricating medium in the bearing assembly, so that this pressure applies the force toward the intake end of the swing tube, which forces the intake end of the swing tube into sealing abutment with a cylinder port.

Abstract: A bouyant foundation comprising a substantially unitary concrete hull defined by bottom, side and end walls; at least one partial bulkhead wall disposed generally normal to and spanning the bottom wall and having a height less than that of the upstanding walls to yield a plurality of recessed flotation cavities bounded by flotation cavity side walls; generally rectilinear flotation block members, having reentrant sidewall portions, disposed within the flotation cavities; restraining wedge members integral with the flotation cavity sidewalls received within the reentrant portions of the flotation block members for fixedly retaining the same within the cavities, and a method for fabricating such a structure comprising the steps of establishing a construction form including bottom, side and end wall form members; depositing a concrete mixture on the form members to yield a substantially unitary hull including concrete bottom side and end walls; positioning a plurality of positive flotation members as internal bu