Abstract: A machine for "dry mix" packerhead concrete pipe manufacture has two stations and a separable tubular jacket movable therebetween. A rotatable cylindrical packerhead is movable axially within the jacket and a "dry mix" delivery means deposits mix atop the packerhead as it rotates and moves vertically upwardly within the jacket. The packerhead distributes the mix thereabout to form a concrete pipe in the jacket. A radially expandable and contractable core is movable axially in a contracted condition to a position within the pipe and is then expanded. Vibrators within the core are operated to "redensify" the pipe; that is, to compact the mass thereof, to eliminate voids, and to relieve residual forming stresses therein. A guide ring is employed to align the contracted core axially with the pipe during entry and further guiding and supporting devices for the core are provided. Core entry and withdrawal is power actuated as is core expansion and contraction within the pipe.

Abstract: A concrete product making machine having a counter rotating packerhead assembly and a concrete supply control operable to maintain a desired amount of concrete in the mold above the packerhead assembly. The counter rotating packerhead assembly has a lower packerhead unit rotated in one direction by a motor and on upper packerhead unit rotated in an opposite direction by hydraulic motors mounted on the cross head of the machine. The upper packerhead unit located above the lower packerhead unit has a plurality of rollers and an annular trowel. The trowel has radially adjustable shoes which meter the flow of concrete to the lower packerhead unit. A control system responsive to hydraulic fluid pressure supplied to the hydraulic motors controls the operation of a concrete supply conveyor operable to deliver concrete to the chamber above the packerhead assembly. The control system includes a control valve assembly operable to regulate the supply of hydraulic fluid to a hydraulic motor operating the conveyor.

Abstract: An apparatus for forming concrete articles of uniform density, which includes means for forming concrete into the form of the articles, and means for sensing the density of concrete in each area of formation in the forming means as the article is being formed, comparing the sensed density to a preset density, and compensating for variation of the sensed density from the preset density responsive to such comparison, such that the density of concrete in each area of formation in the forming means as the article is being formed equals the preset density.

Abstract: In radially centrifugally molding sections of concrete pipe with a bell at one end, the concrete is poured downwardly into an upwardly extending mold which forms the outer surface of the pipe section. The lower end of the mold is shaped to form the bell end of the pipe section. The concrete is centrifugally forced outwardly against the inner surface of the mold and then is pressed outwardly by a series of rotatable rollers. A pressure wheel is located within the mold above the position of the rollers for limiting the upward movement of the concrete pressed outwardly against the mold and for increasing the concrete pressure acting downwardly toward the bell end of the concrete pipe section.

Abstract: A frusto-conical trowel apparatus for smoothing mortar or plastic lining material in a pipe or conduit or other such object which has a generally cylindrical inner surface. The trowel body consists of a plurality of laterally overlapping plate members which are mounted onto an inner frame at the small end of the trowel body; such inner frame and it's support bars being enclosed in a conical device to prevent mortar from entering the trowel body; having small rods connecting a spring member to the inner frame while allowing the spring member to reside at the large end of the trowel body and provide pressure against the trowel plate members in order to establish compressibility diametrically of same, creating needed radial troweling pressure.

Abstract: A machine having two packer heads operable to simultaneously make two concrete pipes. A pair of jackets mounted on a turntable are located in vertical alignment with two packer heads. A gear box mounted on a cross head is connected to downwardly directed shafts operable to rotate the packer heads. The cross head is movably mounted on an upright frame to lower the packer heads into the bottom area of the jackets. Separate controlled conveyors discharge concrete into the jackets above the packer heads. Separately rotatable funnels and stationary wiper blades are used to control the movement of concrete into the jackets. The packer heads are simultaneously rotated and elevated in the jackets to build up the cylindrical walls of the pipes. A dual bell packer is moved into engagement with the pallets at the lower end of the jackets to rotate and vibrate the pallets to form the bell sections of the concrete pipes. A pallet positioner is used to locate the pallets on the turntable.

Abstract: A machine having two packer heads operable to simultaneously make two concrete pipes. A pair of jackets mounted on a turntable are located in vertical alignment with two packer heads. A gear box mounted on a cross head is connected to downwardly directed shafts operable to rotate the packer heads. The cross head is movably mounted on an upright frame to lower the packer heads into the bottom area of the jackets. Separate controlled conveyors discharge concrete into the jackets above the packer heads. Separately rotatable funnels and stationary wiper blades are used to control the movement of concrete into the jackets. The packer heads are simultaneously rotated and elevated in the jackets to build up the cylindrical walls of the pipes. A dual bell packer is moved into engagement with the pallets at the lower end of the jackets to rotate and vibrate the pallets to form the bell sections of the concrete pipes. A pallet positioner is used to locate the pallets on the turntable.

Abstract: The present disclosure relates to a so-called drag trowel which is drawn through a pipe or the like to trowel a layer of mortar or other plastic lining material therein. The trowel is frustoconical, having a small leading end of relatively fixed diameter and a larger trailing end which is adapted to expand and contract in the direction of its diameter. The present disclosure provides a novel means within the trowel for exerting a resilient expansive force thereagainst in a circumferential direction fairly close to the large end of the trowel. The expansion means comprises resilient means extending lengthwise along the inner surfaces of the trowel with means for translating the force of the resilient means to a circumferential expansive force and with means for adjusting the effective force of the resilient means.

Abstract: Apparatus for building underground pipelines by forming a casing in a hole from a forming material which is compacted in the direction from the center of the hole towards its walls. The hole is first filled with the forming material throughout its cross-sectional area and then the material is compacted in the direction towards the walls of the hole. Compaction is effected by a device comprising a rod-shaped body adapted for moving through the hole, the front end of the body being provided with a system of radial ribs.

Abstract: Pipes of short length are moulded in a vertical pipe-making machine by locating a series of rings in a circular mould to divide the length of the mould into several compartments, the compartments are filled with settable material, to form a pipe with the rings embedded in it, and the pipe is divided into short lengths by removing the rings. The rings are held in position by stops projected through the wall of the mould into the moulding space, which are withdrawn prior to demoulding. The rings and reinforcement cages are assembled on a jig that is withdrawn before the pipe is moulded.

Abstract: A molding station having packer heads is positioned between a pair of stripping stations having ejectors and a mold box having first and second mold sections is movable between first and second positions with the ejectors at the one stripping station registering with the one mold section and the packer heads registering with the other mold section and at the second position the ejectors at the other stripping station registering with the other mold section and the packer heads registering with the first mold section. The completed molded product is ejected as the mold box is raised and the molded product is formed as the mold box is lowered. The mold box is raised and lowered between top and bottom table halves and when in the lowered position is movable between the first and second positions on rails having legs adapted to engage a stationary support when the lower table half is lowered a predetermined distance.

Abstract: A machine having two packer heads operable to simultaneously make two concrete pipes. A pair of jackets mounted on a turntable are located in vertical alignment with two packer heads. A gear box mounted on a cross head is connected to downwardly directed shafts operable to rotate the packer heads. The cross head is movably mounted on an upright frame to lower the packer heads into the bottom area of the jackets. Separately controlled conveyors discharge concrete into the jackets above the packer heads. Separately rotatable funnels and stationary wiper blades are used to control the movement of concrete into the jackets. The packer heads are simultaneously rotated and elevated in the jackets to build up the cylindrical walls of the pipes. A dual bell packer is moved into engagement with the pallets at the lower end of the jackets to rotate and vibrate the pallets to form the bell sections of the concrete pipes. A pallet positioner is used to locate the pallets on the turntable.

Abstract: The invention relates to a frustoconical drag trowel which is drawn through a pipe or the like to trowel a layer of mortar or other plastic lining material therein. The frustoconical trowel has a small leading end of relatively fixed diameter and a large trailing end which is adapted to be expanded and contracted in a diametral direction. The present disclosure provides a novel means within the large end of the trowel for exerting a resilient expansive force thereagainst. This means comprises a hollow torus adapted to bear against the interior of the large end of the trowel along the perimeter of the torus.

Abstract: A multi-stage frusto-conical trowel is towed by a machine which travels through a pipe and applies a layer of mortar to the inside surface of the pipe. The multi-stage trowel is carried on a rigid support member which is pivotally connected to the end of a towing rod extending to the rear of the mortar-dispensing machine. A first stage trowel with overlapping arcuate leaves is rigidly attached to the front of the support member and performs rough troweling of the mortar layer. A second stage trowel has overlapping arcuate leaves in which the leaf joints are offset circumferentially from the leaf joints of the first trowel. The second stage trowel is rigidly attached to the rear of the support member and performs finish smoothing of the mortar layer.

Abstract: A frusto-conical trowel made up of a plurality of overlapping arcuate leaves includes an inflatable member within the trowel to bear against the leaves and urge them outwardly with a substantially uniform force against coating material being applied to the inside surface of a pipe.

Abstract: A cap rest assembly to support a closed bore cap slightly above the upper periphery of the pipe jacket in a packerhead/vibration system concrete pipe machine, which has a slump filler attachment enabling making of a green pipe including the upper end in a continuous operation by overfilling the jacket slightly, the cap rest assembly supporting and enabling automatic release of the closed bore cap when the slump filler compression ring depresses the closed bore cap and overfills concrete into the top end of the pipe jacket to complete the green pipe.

Abstract: A novel vibrating core apparatus for use with a concrete pipe making machine. The novel apparatus includes a core, vertically movable into and out of a pipe form, a series of vibrators attached along the interior side wall of the core, an upwardly movable system operative by fluid pressure for raising and lowering the core, and an interlocking connection between a standard packerhead, which distributes cementitious material about the interior of the pipe form, and the upper portion of the core. The packerhead is designed to rotate while forming the pipe; the core does not rotate and the connecting means between the two is easily attached and disengaged from the packerhead.