Abstract: Fresh concrete is treated with carbon dioxide prior to delivery to a product mold for forming concrete products. Carbon dioxide gas is directed through a manifold, which may be coupled to a feedbox or a hopper, upstream from the product mold. Treating the fresh concrete with the carbon dioxide gas while it is in a loose state prior to placement in the product mold may generally promote uniform and enhanced carbon dioxide uptake.

Abstract: A slip molding apparatus (10) for lining a pipe (12) includes a dispense head (20) adapted to engage an interior surface (14) of a pipe (12) and to dispense a lining material, a slip mold (38) pulled by the dispense head (20) and having a leading end (42) and a trailing end (44), wherein the trailing end (44) has a greater diameter than a diameter of the leading end (42), at least one camera (58) disposed on the dispense head (20) to provide a view of the interior surface (14) of the pipe (12), a guide (46) connected to the dispense head (20) and the slip mold (38) for guiding the lining material dispensed by the dispense head (20) about the slip mold (38), and a movable diverter (52) on the slip mold (38) cooperating with the guide (46) to divert a flow of lining material dispensed by the dispense head (20) about the slip mold (38).

Abstract: A connector module includes a housing, a cable, and a gasket. The housing is defined by a first shell and a second shell that mate at a seam. The housing includes a cable exit region defining a passage from a cable opening to an interior chamber of the housing. The cable is coupled to and extends from the cable exit region of the housing. A passage segment of the cable is disposed within the housing along the passage. A distal end of the cable is disposed within the interior chamber. The gasket is helically wrapped around the passage segment of the cable and positioned within the cable exit region of the housing. As the first and second shells are mated, the gasket seals the passage between an outer perimeter of the passage segment of the cable and an inner surface of the cable exit region.

Abstract: The extruder head assembly comprises of a drive shaft connected to a troweling cylinder. A plurality of rollers are spaced around the drive shaft and above the troweling cylinder and intermittently contact an inside surface as the troweling cylinder is rotated and pulled upward. The rollers are either elliptically shaped or round positioned on an eccentric axis for intermittent contact against an inside surface of the concrete pipe. The rollers compact the concrete mixture to form the outer surface and the troweling cylinder follows the compaction by smoothing the surface. The troweling cylinder comprises a plurality of removable sections. Each section is composed of a plurality of removable and replaceable tile segments. When a tile segment breaks, the section containing the broken tile segment can be removed so that the broken tile segment can be replaced.

Abstract: Provided is a floor construction apparatus that includes a guide unit that is disposed on surface of a floor to be constructed, and a flattening unit that is guided by the guide unit, to then be transferred to flatten the surface of the floor to be constructed, and to thereby reduce a construction time and expense for flattening of the construction surface of the floor.

Abstract: The extruder head assembly comprises of a drive shaft connected to a troweling cylinder. A plurality of rollers are spaced around the drive shaft and above the troweling cylinder and intermittently contact an inside surface as the troweling cylinder is rotated and pulled upward. The rollers are either elliptically shaped or round positioned on an eccentric axis for intermittent contact against an inside surface of the concrete pipe. The rollers compact the concrete mixture to form the outer surface and the troweling cylinder follows the compaction by smoothing the surface. The troweling cylinder comprises a plurality of removable sections. Each section is composed of a plurality of removable and replaceable tile segments. When a tile segment breaks, the section containing the broken tile segment can be removed so that the broken tile segment can be replaced.

Abstract: The invention relates to a device and a method for producing a water barrier in unsolidified roof tile preforms. The inventive device comprises a molded piece with a recess as well as a die. The molded piece is disposed above the end of a roof tile perform, whereupon all or part of the rear edge of the roof tile perform is pressed upward by means of the die. The roof tile perform is then dried.

Abstract: A precast concrete meter pit consisting of a plurality of precast concrete hollow elongated cylindrical wall sections in end to end relation to one another is fabricated by utilizing a slip form packerhead apparatus in which the wall sections are formed with an annular slip ring when concrete is injected into the slip form apparatus.

Abstract: The present invention relates to a method and apparatus for fabricating a reinforced concrete cylinder, and more specifically to a method for centering a reinforcing frame within a form used during the placement of a concrete slurry. One embodiment of the present invention includes a plurality of centering arms that are adapted for selective engagement with the reinforcing frame, thus maintaining it in the predetermined radial location during the fabrication process.

Abstract: A concrete pipe making machine having a packerhead consisting of a rollerhead and a longbottom in which the rollerhead and longbottom are quickly assembleable and disassembleable as a unit from the packerhead drive means with one connector and brought into final adjustment off the machine, said drive means providing no obstruction to the flow of wet concrete toward the compaction area, the speed ratios between the rollerhead and longbottom being infinitely variable, and easily replaceable protective wear rings for precluding erosive deformation of the permanent parts of the machine due to undesired penetration of wet concrete into the longbottom.

Abstract: The invention concerns a procedure for the production of tubes from concrete mix, whereby the concrete mix is filled into a shaping device, for the purpose of shaping, where it is condensed with a tool. The invention should enable an effective and fast production of concrete tubes with high quality regarding the uniformity of the material characteristics. In such a procedure the concrete mix is condensed in an interspace between two parts of a tool that rotate relative to each other.

Abstract: A concrete pipe making machine having a packerhead consisting of a rollerhead and a longbottom in which the rollerhead and longbottom are quickly assembleable and disassembleable as a unit from the packerhead drive means with one connector and brought into final adjustment off the machine, said drive means providing no obstruction to the flow of wet concrete toward the compaction area, the speed ratios between the rollerhead and longbottom being infinitely variable, and easily replaceable protective wear rings for precluding erosive deformation of the permanent parts of the machine due to undesired penetration of wet concrete into the longbottom.

Abstract: A new and improved rollerhead for packerhead assemblies employed in concrete pipe making machines utilizing the packerhead method of pipe formation wherein the rollerhead includes a roller shaft having an upper end and a lower end, a hollow cylindrical roller body rotatably disposed around the roller shaft, a first bearing coaxially mounted about the upper end of the roller shaft and contacting an inside surface of the roller body, a second bearing coaxially mounted about the lower end of the roller shaft and contacting an inside surface of the roller body. The improvement comprises a roller body including a radially inwardly directed flange, an annular body mounted coaxially about the roller shaft, and an annular seal coaxially disposed about the annular body.

Abstract: A method and apparatus for making concrete pipe with a packerhead concrete pipe making machine having a lift operable to selectively raise and lower the packerhead during the forming of a concrete pipe in a mold while a conveyor delivers a constant supply of concrete to the mold. The operating speed of the conveyor only increases or decreases when the motor load signal which is proportional to the load on the motor that turns the packerhead falls below or goes above lower and upper motor load reference limits. The lift speed of the packerhead varies with the vertical positions of the packerhead relative to the mold.

Abstract: A concrete pipe manufacturing machine movable in a mold for receiving a concrete mixture to form a tubular concrete wall includes a troweling cylinder assembly having a head plate. A vertically movable and rotatable drive shaft is fixed to the head plate for moving the troweling cylinder assembly in a vertical direction and in one rotational direction. A series of roller assemblies are rotatably mounted on the head plate and are adapted to be rotated by frictional contact with the concrete mixture in a direction counter to the one rotational direction of the drive shaft. A drive arrangement interconnects and collectively drives the roller assemblies together for preventing jamming of the roller assemblies due to material in the concrete mixture.

Abstract: A production system for automatically casting hollow bodies, in particular of concrete, in a casting mold, which comprises an inner mold (2), an outer mold (1), a bottom ring (3), and a top ring (4). Separate top rings (4) are used for the production, which remain on the top end of the pipe until the concrete has set sufficiently, to ensure that the shape and tolerances of the top end of the pipe are retained after casting. The system moreover includes a clamping chuck (15) for retaining the top ring during casting. The clamping chuck is equipped with a clamping device that includes a ring-shaped flexible hose and a slotted spring ring. When the hose is filled with compressed air from a compressed air source, it clamps the spring ring together around a gripping ring on the top ring.

Abstract: A method and a system for the production of shells of fat-containing, chocolate-like masses. A cooling member (1) having a temperature below 0.degree. C. is immersed in a predosed mass in a mould cavity (2). The cooling member (1) comprises protruding, peripheral engagement parts (4) having a recess (7, 8) which defines a reception volume that geometrically determines the upper, annular rim of the shell (10). This obviates further processing of the shell rim before the shell is joined with other parts. A tight joint is simultaneously ensured.

Abstract: A compaction head of a production machine for reinforced concrete pipes has a smoothing cylinder, non-rotatably mounted on its drive shaft, for smoothing the inside of the concrete mixture that has been filled into a vertical mold. On a covering wall of the smoothing cylinder, the rolls, for the radial compaction of a concrete mixture, are mounted axis-parallel and orbiting on a circular path around and driven by the drive shaft at a specified orbiting speed about the axis of the drive shaft and about their own axis, such that the direction of rotation of each of the rolls about its own axis is opposite to that of the covering wall also driven by the drive shaft.

Abstract: A counter-rotating compaction head for manufacturing a concrete pipe is vertically positioned in a vertical mold within the longitudinal axis of the mold so as to be rotatable about and axially slidable along the longitudinal axis of the mold. The counter-rotating compaction head has a distributing head with distributing devices for distributing concrete and a cylindrical mantle. A first drive shaft rotates the distributing head. A smoothing piston with a smoothing mantle is rotatably driven by a second drive shaft counter to the distributing head. At least one vibrator for compacting and smoothing an inner wall surface of the concrete pipe to be manufactured is operatively connected to at least one of the cylindrical mantle of the distributing head and the smoothing mantle of the first smoothing piston so as to vibrate the respective mantle.

Abstract: A machine serves to cast pipes of concrete or a similar material substantially vertically. The machine includes an inner mould part (2) and an outer mould part (12). These mould parts are displaced axially with respect to each other during the casting process. A vibrator is preferably provided upwardly in the inner mould part (2), and an axially journalled distributor wheel (1) is rotatably mounted on the top of the mould part (2) the distributor wheel (1) having a plurality of blades (4) for distributing the material in the ring gap between the two mould parts (2, 12). The distributor wheel (1) and its mount are constructed so stiffly that the vibrations generated by the vibrator are transmitted to the material through the blades of the wheel. This ensures, when a firm profile ring is used for the casting of the spigot end, that area of difficult access below said ring is filled completely with concrete, and that the concrete obtains the prescribed quality.

Abstract: A method for manufacturing concrete panels by continuously pressing and an apparatus for carrying out the method. The concrete panels are successively manufactured by continuously feeding pallets onto a conveyor, feeding a concrete material onto the pallets, continuously pressure frames against the concrete material from the upper side and both lateral sides of the concrete material while imparting vibrations to the pressure frames, forming hollows in the concrete material by thrusting a rotary screw-type core rod therethrough to provide a panel shape hollow molding, and cutting the molded concrete material into a length corresponding to the length of each pallet. In the manufacture process, an organic or inorganic fiber material may be incorporated into the concrete material for the purpose of reinforcement of the finished products.

Abstract: An improved combination counter rotating packerhead and vibrator assembly is provided. A counter rotating packerhead including counter rotating roller assemblies, longbottom assemblies or a combination thereof is disposed directly over an annular pneumatic vibrator. The coaxial drive shaft for the counter rotating packerhead passes through the vibrator thereby permitting the power transmission means to be located below, and isolated from, the vibrator. The vibrator is disposed below, but adjacent to, the counter rotating packerhead for faster pipe production.

Abstract: The invention relates to a chimney lining device which includes a shell member which telescopically embraces the exterior of a bell member. A shell member of desired dimensions may be used in conjunction with a standard sized bell member for the lining of various sized chimneys. Both the bell member and the selected shell member are formed of one-piece construction enhancing the durability and performance of the chimney lining device. During use, the invention is generally lowered to the bottom of a chimney whereon a masonry mortar compound is deposited within the chimney covering the chimney lining device. The chimney lining device is then activated causing the vibration of the bell member and the shell member. The chimney lining device is then slowly raised within the chimney, which causes a uniform and compacted thickness of masonry mortar compound to be deposited to the interior walls of the chimney.

Abstract: A concrete pipe making machine having a pair of combined roller head and vibrating core assemblies are used with two molds to prepack and vibrate concrete within the molds to simultaneously produce two concrete pipes. A controller is programmed in response to packing forces of the packerheads to control conveyors that discharge concrete into the molds and the lift speed of the packerhead and core assemblies to produce concrete pipes having uniform density throughout the length of the concrete pipes.

Abstract: In the extrusion of hollow core concrete slabs, the density profile across the slab is controlled by the vibration of a hammering plate forming one side of a packing chamber through which the concrete is extruded. Vibrations are imparted to the hammering plate by a vibrator that acts to produce vibratory motions in the plate that are not parallel to the direction of extrusion. With two vibrators producing vibratory components both in the direction of extrusion and outwardly to opposite sides of the packing chamber, the flow of concrete to the side edges of the slab is augmented. In an auger-type extruder, this allows the outer augers to be run at a slower speed than otherwise, thus increasing their service life. The vibratory frequency may also be reduced considerably, thus reducing the noise generated by operation of the apparatus.

Abstract: A concrete pipe making machine having a vibrating core and counter-rotating roller head is used to form a concrete pipe within a form. A concrete pipe reinforcing cage located within the form is held in spaced relation relative thereto with a plurality of cage positioners. Each cage positioner has a moveable blade connected to a piston and cylinder assembly operable to move the blade to a cage holding position and a blade retracted position out of engagement with the cage. The piston and cylinder assembly has a cylinder with a internal chamber having a rectangular cross section. A rectangular piston within the chamber is secured directly to the blade.

Abstract: A concrete pipe making machine having a pair of combined roller head and vibrating core assemblies used with two molds to prepack and vibrate concrete within the molds to simultaneously produce two concrete pipes. A controller is programmed in response to packing forces of the packerheads to control conveyors that discharge concrete into the molds and the lift speed of the packerhead and core assemblies to produce concrete pipes having uniform density throughout the length of the concrete pipes.

Abstract: A concrete pipe making machine having a pair of combined roller head and vibrating core assemblies are used with two molds to prepack and vibrate concrete within the molds to simultaneously produce two concrete pipes. A controller is programmed in response to packing forces of the packerheads to control conveyors that discharge concrete into the molds and the lift speed of the packerhead and core assemblies to produce concrete pipes having uniform density throughout the length of the concrete pipes.

Abstract: An extrusion machine for making hollow elongated articles of concrete has an eccentric compaction disc that reciprocates and rotates to compact and release air from zero slump concrete. The machine avoids having to have a high frequency converter which is both expensive and noisy. At least one extruder screw is provided in the machine to feed concrete and form the elongated article. The screw has a die former at the outlet end to form a cavity in the elongated article. An eccentric compaction disc is positioned between the outlet end of the extruder screw and an input end of the die former, the input end of the die former is eccentric and coplanar with an eccentric disc face mounted for movement in a circular orbital path about the extruder screw axis. The output end of the die former is concentric with the extruder screw axis.

Abstract: A packerhead assembly for use in making concrete pipes. The packerhead assembly includes a rollerplate with rollers mounted thereto, and a long segmented longbottom assembly comprised of two substantially identical troweling members, one of which is inverted with respect to the other. The two troweling members combine to form an elongated troweling surface which allows the use of concrete mixes having high fluidity. The longbottom assembly also utilizes removable wear bands which limit the ingress of concrete material to the interior of the longbottom assembly. The wear bands are of particular value when utilizing highly fluid concrete mixes.

Abstract: A concrete pipe is produced by introducing a wet concrete mass into a pipe form to produce a cylindrical mass having an inner wall, compacting the cylindrical concrete mass by applying pressing rollers to the inner wall, smoothing the inner wall of the compacted cylindrical concrete mass, and applying a liquid impregnation medium to the inner wall under pressure after the concrete mass has been compacted, the inner wall has been partially smoothed and the concrete mass is still damp. The pressure is sufficient to cause the impregnation medium to permeate the damp concrete mass to a depth of at least 10 mm.

Abstract: A device for manufacturing concrete parts, particularly concrete pipes, and based on the principle of sinking mold whereby a molding bottom ring together with a jacket are continuously lowered relative to a stationary mold core while concrete mixture is poured from above and distributed into the emerging molding space by a radial pressing device mounted on the top end of the mold core. Simultaneously with the lowering of the mold jacket and the molding bottom ring a supply device for delivering the concrete material is also lowered such as to keep a constant distance from the open top end of the mold jacekt. The radial pressing device is designed to compact the incoming concrete material in radial direction without imparting any torque thereto. In this manner any stress in the finished part, particularly between the concrete and reinforcing wire mesh is effectively avoided.

Abstract: Rammed building walls having an earth core and integral cement jackets are formed by placing a rectangular earth hopper within a rectangular wall moulding cavity that is defined by formwork members which are aligned with an underlying foundation. The hopper is filled with earth while outside of the moulding cavity and has a trapdoor as its bottom. The moulding cavity has a substantially greater width than the width of the hopper so that jacket cavities are formed on either side of the hopper. A pair of tiltable cement hoppers, filled with concrete or a sand and cement mix, are mounted on the earth hopper and are tiltably unloaded into the jacket cavities. The trapdoor is then released so that the earth slides downwardly and laterally, and the hoppers are lifted as a unit out of the moulding cavity while the earth fills a core cavity between the mix-filled jacket cavities. Both the earth and mix are then rammed simultaneously.

Abstract: An apparatus for continuously shaping and extruding concrete or other moldable material as a decorative curbing. The apparatus is operable by one person at high extrusion velocity, negotiates short radius serpentine curbing paths, and is maneuverable in tight spaces because of side-to-side and vertical adjustment features, and a short "wheel base". Moldable material is placed in a hopper and flows into an auger which compresses, mixes and extrudes the material through a shaped, non-flanged mold into the desired curb bed. A fueled engine or electric motor drives a hydraulic pump to pressurize hydraulic fluid. The pressurized fluid drives a hydraulic motor which turns the auger. The speed is controlled by simply setting a fluid flow valve.

Abstract: A casting containing toxic waste is made by centrifugally casting toxic waste in a pre-formed cage having heat conducting means therein. The casting is formed with suitable shielding materials selected as a function of the waste being cast. The finished casting may contain passageways through which heat is removed. These passageways are oriented such that when two or more castings are stacked in abutment, the passageways of adjacent castings interconnect. Also disclosed is a method and apparatus for forming castings of polygonal exterior cross section having a contaminant barrier wall of substantially uniform thickness so that the waste storage volume of the castings is maximized and so that the castings may be stacked and stored in honeycomb fashion in a respository to minimize dead storage space.

Abstract: Auxiliary or stub augers are used in conjunction with a convention auger machine that is used to form reinforced hollow cored slabs. They can be used to ensure consolidation of concrete above the cores particularly and relatively in large diameter slabs or can be substituted for one or more of the conventional core forming augers if a core or bore is not required in the slab at that location. The stub auger consists of a first portion having a non tapering shaft and a non tapering flight thereon. The second or downstream portion has a gradually reducing diameter shaft with the flight which continues from the flight around the first portion, decreasing in diameter to substantially zero at the extreme downstream end of the shaft.

Abstract: A concrete pipe making machine having a combined vibrating core and counter rotating packerhead assembly is used with a mold to prepack and vibrate concrete within the mold to produce concrete pipe. A controller is programmed in response to packing force of the packerhead assembly to control the discharge of concrete into the mold and the lift speed of the core and packerhead assembly to produce concrete pipe having uniform density through out the length of the pipe.

Abstract: A method of lining a pipe comprises the steps of laying hose means along the bottom of a pipe to be lined, the hose means having been filled with a predetermined quantity of settable lining composition, anchoring the hose means at each end along the bottom of the pipe, advancing a centrifugal lining machine along the length of the hose means, slitting the hose means in front of the advancing centrifugal lining machine to permit egress of the lining composition from the hose means, and delivering the admixed settable composition to a centrifugal impellor of the centrifugal lining machine for application of the settable composition to the pipe wall as the centrifugal lining machine advances along the pipe. The method is characterised by the step of guiding the slit and emptied hose means through an axial bore in the centrifugal lining machine to lie in a flattened condition on the bottom of the lined pipe wall rearwardly of the centrifugal lining machine.

Abstract: The invention concerns a slip-form casting machine for fabrication of elongated concrete products. The slip-form casting machine comprises a feed hooper (1), an auger (6) for exerting pressure onto a concrete mix to be cast, and a casting mold (10, 11). According to the invention, the casting mold (10, 11) is a tubular construction plugged at one end, and the auger (6) is connected to a casting machine body (18) which is substantially complementary with the cross section of the casting mold (10) and is movable with respect to the mold (10) in order to facilitate slip-form casting of a product (7) with an elongated shape in the axial direction of the casting mold. The slip-form casting machine in accordance with the invention produces smooth and high-quality surfaces in concrete products.

Abstract: The invention is concerned with an hydration means for wetting the exposed surface of a core void formed on the withdrawal of a core former from a construction panel comprising compacted gypsum or like particulate materials, and proposes the free suspension of a reciprocable spray head by a flexible small-bore tube through which a setting liquid is applied to the spray head from a cross-head with which the tube is connected in fluid flow relationship. If necessary, the spray head may be weighted, while an apertured guide plate through which the tube passes may be provided above the upper limit of movement of the spray head.

Abstract: Method and slide-casting machine for the casting of hollow precast units of concrete by means of slide-casting. Concrete mix is extruded onto a base by using one or several shaping members that form a cavity and the mix is compacted by moving the shaping members. The outer face of the shaping members is provided with a projection or projections, or a projection or projections are formed at the outer face of the shaping members from time to time. The locations of the projections are changed to the longitudinal axis of the shaping members. Thereby the shaping members produce forces compressing the mix in the surrounding mix, i.e. forces that compact the concrete. It is possible to use shaping members in which the shape of the mantle portion can be changed so that the distances of the different points at the outer face of the shaping member from the longitudinal axis of the shaping member vary.

Abstract: A method of lining pipes comprises the steps of laying along the pipe (56) hoses (63) filled with constituent components of a settable resinous lining composition, axially slitting the hoses, conveying the constituent components to a mixing chamber (65), and centrifugally impelling the mixed lining composition against the wall of the pipe (56). A lining apparatus (50) for carrying out the method is advanced along the pipe (56) and comprises delivery tubes (62) with slitting blades (70) at their leading ends which are pushed through the holes (63) and which communicate with a mixing chamber (65) which, in turn, is open to a centrifugal impeller (57) of a lining machine. The slit and emptied hoses (63) may be left in situ in the pipe (56) or removed therefrom in advance of the lining apparatus (50). A trowelling arrangement using a thin-walled, flexible tube (112) of, for example, a cellulose polymer and a conical trowel (112) is employed to smooth the pipe lining.

Abstract: An apparatus for lining chimney pipes and the like with cementitious material, and particularly to the improvement in pipe lining apparatus including a conically shaped leading nose providing control switches activated by a nose cap freely positioned thereover, and a gradually rearwardly tapered hollow sectional trailing spreader body adjusted to be circumferentially enlarged by additional expansion panels connected between the separable sections of the spreader body, and a vibrator within the body to exert vibrative force on the body sections to set the cementitious material deposited externally of the apparatus between it and the chimney pipe to be lined thereby.

Abstract: A device is described for positioning a reinforcing cage within a cylindrical concrete pipe form. The device comprises a horizontally movable slide which may be moved inwardly into the form for engagement with the cage. A cam is secured to the slide for moving the slide inwardly and outwardly relative to the form. An air cylinder is pivotally connected to the cam for pivotally moving the cam. An adjustable stop is located in the pivotal path of the cam to limit the inward movement of the slide. A plurality of the devices are mounted on the form in a radially spaced and vertically spaced manner.

Abstract: A packerhead concrete pipe making machine having a rotatable packerhead operable to form a concrete pipe in an upright cylindrical mold about a wire cage. The packerhead has a plurality of rollers rotatably mounted on a circular plate operable to pack concrete into a cylindrical shape in the mold. Each roller has an outer sleeve of elastic rubber material. A cylindrical wall secured to the plate supports an annular troweling member operable to finish the inside surface of the concrete pipe.

Abstract: A method and apparatus for making concrete pipe having substantially uniform density throughout the length of the pipe has a packerhead which is rotated and lifted within a mold, and a conveyor for feeding concrete into the mold. A combined conveyor speed and packerhead lift control operates in response to the amount of power used to rotate the packerhead to slow the speed of the conveyor to a desired speed and change the lift speed of the packerhead when the load on the motor for rotating the packerhead exceeds a selected upper load limit or falls below a selected lower load limit.

Abstract: A packerhead, a concrete pipe making machine having said packerhead, and a method of making concrete pipe are disclosed in which twist forces on the reinforcing wire cage of the pipe and concrete voids are eliminated by rotation of the longbottom and rollerhead portions of the packerhead in opposite directions. The peripheral speed of the system is also increased over conventional systems.

Abstract: An apparatus is disclosed for centering a reinforcing mesh which is in a pipe or conduit form for manufacturing reinforced concrete pipe or conduit. In order to automatically center the reinforcing mesh in a simple and reliable fashion, a plurality of mesh centering units are provided which are distributed at spaced intervals around the perimeter of the form. Each of these units comprises at least one radially outwardly extending member which penetrates through a receiving slot into the form to a depth which is adjustable depending on the external diameter of the reinforcing mesh. When the concrete introduced into the form is compacted, the member can be retracted to an inactive position from the operating position, in which it biases against the centered mesh.

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 first packerhead unit rotated in one direction by a motor and a second packerhead unit rotated in an opposite direction by hydraulic motors mounted on the cross head of the machine. The second packerhead unit located above the first 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 first 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: In order to form concrete pipe of uniform density in apparatus where a packer head packs concrete into a mold to form the pipe, the horsepower of the drive motor driving the packer is sensed and used to adjust the rate of concrete supply such as to insure a constant horsepower as the packer is moved from one end of the pipe mold to the other.