Abstract: In abstract, a preferred embodiment of this invention is a multi-purpose form system for use in culverts, manholes and other locations. A basic semi-cylindrical form is provided for use in combination with other types of forms to give a complete system for accomplishing the results intended.

Abstract: A form assembly which may be used to provide a core portion in a concrete or other cast structure. A pair of former elements having interfitting hooks and flanges which are normally urged apart by a resilient sleeve which fits over the former elements. The sleeve biases the former elements to a collapsed position in which they may be inserted and removed. An inflatable tube is interposed between the former elements and may be inflated to move the elements to an expanded position wherein forming surfaces of the elements cooperate to provide a core about which concrete or the like may be poured.

Abstract: A method and apparatus for making concrete pipe and, more particularly, for the vibration treatment of concrete pipe for compaction and residual stress relief. A concrete pipe is formed within an external jacket employing a rotary packerhead method wherein the jacket is positioned vertically and the packerhead is moved progressively upwardly within the jacket rotating and distributing mix radially outwardly and troweling the internal surface of pipe under formation. On completion, the green pipe is removed from the pipe making machine and transported to and above a hollow vertically split and radially expandable and contractable cylinder. The pipe is lowered about the cylinder with the latter in a contracted condition, the cylinder is expanded into engagement with the pipe internal surface, and a vibrating means within the cylinder is actuated to vibrate the pipe throughout its length.

Abstract: A core member used in a moulding flask for making prefabricated concrete products, comprising a hollow tubular member of predetermined size having all outer surfaces intended to be in contact with concrete mixture covered by a thin layer of rubber plate.

Abstract: Molding apparatus for molding hollow articles without a seam or parting line even though the articles may have backdraft or undercut portions on both the inside and outside surfaces. The apparatus includes a generally one-piece flexible mold having a generally thick self-supporting wall construction which is deformable by the application of a fluid pressure differential. The mold includes a generally hollow outer portion and a generally hollow inner portion integrally formed with and extending upwardly from the bottom wall of the outer portion, said mold portions defining an upwardly opening generally annular cavity into which hardenable material is placed.

Abstract: A molding device including a rigid container defining a molding chamber and a mating collapsible member with walls and a floor and of a normal size and shape to mate in the rigid container and define a molding space between the container and the collapsible member; the collapsible member includes means to collapse it through a first stage of movement of withdrawal of the walls inwardly from a molded object and a second stage of movement of withdrawal of the floor axially upwardly away from the container and a molded object.