Abstract: Systems and methods for operating hydraulic fracturing units to pump fracturing fluid into a wellhead may include receiving a target flow rate and/or a target pressure for fracturing fluid supplied to the wellhead. The systems and methods may increase a flow rate from the hydraulic fracturing units according to a controlled increasing flow rate schedule toward the target flow rate and/or target pressure. When it has been determined the target flow rate and/or target pressure has been achieved, the systems and methods also may include operating the hydraulic fracturing units to maintain the target flow rate and/or target pressure. When the target flow rate has not been achieved, the systems and methods also may include generating notification signals, and/or when the target pressure has not been achieved, the systems and methods further may include operating the hydraulic fracturing units to maintain a maximum flow rate.

Abstract: Methods and systems for controlling proppant concentration in a hydraulic fracturing slurry include measuring volumetric flow rates of fracturing fluid input to a blender and hydraulic fracturing slurry output from the blender, using these measured values to calculate a volumetric flow rate of proppant input, a slurry density and/or a slurry volume fraction, adjusting first and second valves to control rates of fluid and proppant delivery to the blender and re-measuring the volumetric flow rates and recalculating until target values of volumetric flow rate of proppant input, slurry density and/or slurry volume fraction are achieved.

Abstract: Embodiments relate to a hydraulic fracturing system that includes a blender unit. The system includes an auger and hopper assembly to receive proppant from a proppant source and feed the proppant to the blender unit for mixing with a fluid. A first power source is used to power the blender unit in order to mix the proppant with the fluid and prepare a fracturing slurry. A second power source independently powers the auger and hopper assembly in order to align the hopper of the auger and hopper assembly with a proppant feed from the proppant source. Thus, the auger and hopper assembly can be stowed or deployed without use of the first power source, which is the main power supply to the blender unit.

Abstract: An automatic height adjusting robot has a base frame, an L shaped lifting base assembly, a lifting frame, a hoist assembly, an automated mixing assembly, a power inlet, and a screw conveyor. The automatic height adjusting robot computes controlled volumetric ratios of dry chemicals while connected to a production well.

Abstract: A fiber injector (8) has a fixed attachment (10) rigidly secured to the end of a material delivery boom. The fixed attachment (10) has a control handle (20) for controlling the location of the boom and distribution of fibers (62) into the material flowing through the boom. A rotary attachment (30) is rotatably secured to the fixed attachment (10) and is selectively rotated by an electric motor (12). A fiber distribution ring (40) is removably secured to the rotary attachment (30) and has a number of box holders (50) for receiving fiber boxes (60). The fiber boxes (60) contain the fiber (62) being injected into a material flow stream. A fiber brake (24) is mounted for selectively moving to cover fiber delivery apertures (52) in the fiber distribution ring (40) to selectively stop injection of the fiber (62) into the material flow stream.

Abstract: For each of a plurality of production facilities, a series of operations is performed. For each of a plurality of batches of a concrete mixture produced at the respective production facility based on a formulation, a first difference between a measured quantity of cementitious and a first quantity specified in the formulation is determined. A first standard deviation is determined based on the first differences. For each of the plurality of batches, a second difference between a measured quantity of water and a second quantity specified in the formulation is determined. A second standard deviation is determined based on the second differences. A first benchmark is selected from among the first standard deviations, and a second benchmark is selected from among the second standard deviations. An amount by which costs may be reduced by improving production at the production facility to meet the first and second benchmarks is determined.

Abstract: An atmospheric storage mechanical weigh batch blend plant is shown with atmospheric storage for providing a dry, pre-blend, oilfield cement ready for mixing at the wellhead for slurry injection into a well head upon adding the proper amount of water and other fluids. The batch blend plant has three separate weighing mechanisms for (a) larger or bulk quantity materials, (b) intermediate quantities of materials, and (c) small amounts of additives to be included to the mixture. The entire weigh batch blend plant can be disassembled and moved. A special pressurized air bearing is used in the blender.

Abstract: A machine for continuous casting of pre-mortared masonry panels includes a rotatable continuous mold for continuously forming pre-mortared masonry panels and an application system for applying polymeric material to the continuous mold as the continuous mold rotates. The machine also includes a brick setter system for setting bricks onto the polymeric material as the continuous mold rotates. The machine further includes a cutting device for cutting the bricks and polymeric material into panels to form the pre-mortared masonry panels.

Abstract: Improved single screw extruders systems (40) are provided including a single screw extruder (42, 92) as well as an upstream preconditioner (44). The extruders (42, 92) include a single, internal, elongated, helically flighted, axially rotatable screw assembly (52) having one or more improved screw sections (74, 74a, 76). The screw sections (74, 74a, 76) include specially configured flighting (86) wherein adjacent flighting portions (86a, 86b) have smoothly arcuate surfaces (88) extending between the respective flighting portion peripheries (90a, 90b). This flighting design provides smooth, substantially surge-free operation while increasing SME and cook values. The preferred preconditioner (44) has independently controlled mixing shafts (106, 108) allowing the shafts (106, 108) to be rotated at different rotational speeds and/or directions.

Abstract: An apparatus for on-site manufacturing of lightweight concrete used for insulation in roof decks and roof systems of building structures. The apparatus is supported on a transportable trailer frame and includes a mixer, a concrete pump, and one or more tanks for holding a mixture of water and chemical products, such as foaming agents. The chemical agents/water solution is mixed with pressurized air according to a desired foam density and volume and is pumped through a foam cylinder ejector. The air/solution mixture exiting the ejector is directed into a carburetor which generates a foam product by mechanical impact of the air/solution mixture with beads contained in the carburetor. Concrete and the foam product are combined in the mixer, in accordance with a predetermined mixture ratio, and released into the concrete pump for forced discharge from the apparatus and application to a roof structure.

Abstract: A concrete delivery system includes a hopper having an open top and a discharge opening therein. A belt is trained around the front roller and the rear roller and the discharge opening is provided at the lower end of the hopper. A first positive displacement pump is connected to the liquid container and is driven by a rotatable shaft attached to one of the front or rear rollers for delivering the liquid from the liquid container to the mixer. A mixer is provided for mixing the material with the liquid and concrete mixture. The device includes a minimum of adjustment controls. An add mix fluid attachment may also be included in the addition to the liquid dispenser and this is controlled by the same shaft as the liquid dispenser is controlled.

Abstract: A process employing a wet mixer having a vertical mixing chamber for forming a wet slurry of a cementitious powder and liquid. The vertical mixing chamber is designed to provide the required amount of mixing to provide thoroughly mixed, uniformly thin slurry within a mixing residence time that allows for adequate supply of slurry to ensure continuous operation of an associated cement panel production line. Gravity feed for supply of cementitious powder and water to the slurry mixing area of the chamber is also disclosed.

Abstract: A wet mixer apparatus and method for its use, the mixer having a vertical mixing chamber for forming a wet slurry of a cementitious slurry and water. The vertical mixing chamber is designed to provide the required amount of mixing to provide thoroughly mixed, uniformly thin slurry within a mixing residence time that allows for adequate supply of slurry to ensure continuous operation of an associated cement panel production line. Gravity feeding for separate supply of cementitious powder and water to the slurry mixing area of the chamber without pre-mixing of the powder and water is also disclosed.

Abstract: A process for manufacturing plasterboard and a plasterboard manufacturing unit are provided, the process including feeding hydratable calcium sulphate and water into a first mixer (2) and into a second mixer (3); feeding in a facing (5); preparing a first gypsum slurry in the first mixer (2); preparing a second gypsum slurry in the second mixer (3); applying the first slurry onto the facing and forming a crude surface layer; applying the second slurry onto the crude surface layer and forming a crude core layer with a density lower than that of the crude surface layer; forming a plasterboard; hydrating and drying the board. This process allows the formation of the different layers of gypsum to be controlled independently.

Abstract: A wet mixer apparatus and method for its use, the mixer having a vertical mixing chamber for forming a wet slurry of a cementitious slurry and water. The vertical mixing chamber is designed to provide the required amount of mixing to provide thoroughly mixed, uniformly thin slurry within a mixing residence time that allows for adequate supply of slurry to ensure continuous operation of an associated cement panel production line. Gravity feeding for separate supply of cementitious powder and water to the slurry mixing area of the chamber without pre-mixing of the powder and water is also disclosed.

Abstract: A concrete batch mixing system and method are disclosed that enable the batch master to measure and control both the water and cementitious ingredient feeds in relation to each other so as to be able to blend the two ingredients in a known, selected, adjustable and repeatable manner, and to agglomerate these ingredients in a counter-rotating twin screw mixing apparatus for use in the preparation of batches of mixed concrete in a concrete batching process.

Abstract: An apparatus and methods for blending and for delivering additives, for example, in pelletised form, to form thin surface dressings for the pavement construction industry. One or more additives may be weighed, blended and transferred for combination of the blended pelletised additives into an aggregate and bitumen mix.

Abstract: The present invention to provides for a novel asphalt mixing plant which is portable, that is, capable of being transported from one site to another. The portable asphalt mixing plant has a control system that adjusts the rate at which crumb rubber is added to oil so as to maintain a constant oil/rubber ratio in a mixer. The blending control process has a CPU to control the rate at which asphalt is pumped into a mixer and the rate at which crumb rubber is fed to the same mixer so as to maintain a constant asphalt rubber ratio in the produced asphalt.

Abstract: A dual conveyor apparatus transports two cement-making materials in opposite directions. The two conveyors share a common channel so that the materials intermix during transport. The conveyors a driven by a motor, one conveyor rotating in a first direction and the other conveyor rotating in the opposite direction. Each conveyor extends upwardly at an incline from its feed end to its discharge end. The rotation of each conveyor can be altered to vary both the blend and the throughput of the device.

Abstract: A method for weight blending of granular materials comprises at a remote site generating a command for desired operation of granular material weight blending apparatus; encoding said command into transportable time-stable machine readable tangible storage media; transporting said media to a bar code reader operatively connected to said granular material weight blending apparatus; scanning the tangible media having the command encoded thereon to read the command; and providing the read command as input to a in microprocessor operatively connected to said granular material weight blending apparatus for regulating operation of the same.

Abstract: A mixer for dry powder, very fine or granular materials and a liquid, e.g., mortar or cement and water, includes a dynamic input mixing stage, a static output mixing stage and a transition tube connecting the two stages in a manner which isolates the two stages from one another. The input mixing stage includes a hopper for receiving the mortar and a horizontal metering screw having a detachable mixing auger. The auger mixes the dry mortar, while the metering screw moves the mixed mortar through a discharge aperture in the hopper and into the transition tube. The metering screw extends into the transition tube for further displacing the dry mortar into the output mixing stage which includes a mixing tube having a fixed internal baffle assembly and an auger disposed along its length. A source of water is connected to the mixing tube for forming a mortar-water slurry.

Abstract: Apparatus for mixing cementing material and mineral aggregate includes a container having a first chamber and a second chamber each having a top and a bottom. Cementing material is in the first chamber. Mineral aggregate is in the second chamber. An auger is attached to the bottom of the first and second chambers to receive and dispense cementing material from the first chamber and mineral aggregate from the second chamber. The mineral aggregate is dispensed at a rate different from that of the cementing material. The container includes extendable legs and is carried on a lift at the rear of a vehicle. The lift is raised to permit the container legs to be extended. After the legs are extended, the lift is lowered and the vehicle is driven away, leaving the container free-standing on its legs.

Abstract: An apparatus for high capacity production of high-fluidity, colloidally mixed cement slurry. Water and cement dust are combined at metered rates by a premixing assembly which discharges into a mixing tub. The high-speed, high-shear pump recirculates the material through the tub to produce the colloidally-mixed slurry. The high-fluidity slurry may be provided to a second pump, preferably of the positive-displacement, progressive-cavity, rotor-stator type, for supplying the slurry at a metered rate. Finished foam material may also be provided to the slurry metering pump at the metered rate, so the materials are mixed to form a foamed cement grout in which the weight and quality of the material is precisely adjustable.

Abstract: Portable metering and mixing apparatus includes a trailer having a hopper thereon divided into two compartments, one compartment for sand material and another compartment for cementitious material. Screw conveyor assemblies, or auger assemblies, receive the materials and convey the materials to a mixer assembly. Different embodiments are disclosed. One embodiment includes a mixing chamber aligned with an auger assembly and to which the mixing chamber materials are fed directly. Another embodiment discloses a separate mixer assembly to which the materials are conveyed by a pair of auger assemblies.

Abstract: An automatic cementing system and method are disclosed for precisely controlling the density of a slurry during a continuously mixed cement application. The system includes an input water line and a dry cement hopper for supplying water and cement, respectively, to a mixing chamber. The mixing chamber includes two chambers, Chamber A and Chamber B, for thoroughly mixing the water and cement together to form a cement slurry. Chamber B includes a level sensor for measuring the change in slurry level. The input line includes a pump for supplying the water to the mixing chamber, and a flow meter for measuring the rate at which the water is supplied. Similarly, the hopper includes a slide-gate valve for regulating the rate at which the dry cement is supplied to the mixing chamber. A discharge line with a discharge pump and a discharge flow meter receives and discharges cement slurry. A recirculation line is included for density control during initialization.

Abstract: Portable metering and mixing apparatus includes a trailer having a hopper thereon divided into two compartments, one compartment for aggregate and another compartment for cementitious material. An auger receives aggregate from one compartment and feeds aggregate into a mixing compartment where cementitious material is added, and the resulting mixture is then delivered as required. Metering elements meter the aggregate and the cementitious material as desired, and the metered aggregate and cementitious material are mixed in a mixing chamber. A metering sleeve over the auger insures that only the metered amount of aggregate is conveyed by the auger to the mixing chamber. A second embodiment utilizes only a single hopper which contains premixed aggregate and cementitious material, and the premix is fed to the auger through a metering sleeve. Water is added to the material while in the auger and prior to the mixing chamber.

Abstract: An automatic cementing system and method are disclosed for precisely controlling the density of a slurry during a continuously mixed cement application. The system includes an input water line and a dry cement hopper for supplying water and dry cement, respectively, to a mixing chamber. The mixing chamber includes two chambers, Chamber A and Chamber B, for thoroughly mixing the water and cement together to form a cement slurry. Chamber B includes a level sensor for measuring the change in slurry level. The input line includes a pump for supplying the water to the mixing chamber, and a flow meter for measuring the rate at which the water is supplied. Similarly, the hopper includes a rotary valve for regulating the rate at which the dry cement is supplied to the mixing chamber and a speed sensor for measuring the speed of the rotary valve. A discharge line with a discharge pump and a discharge flow meter receives and discharges cement slurry.

Abstract: A system and method for mixing particulate cement with mineral aggregate(s) so as to minimize the formation and escape of dust. The system involves dispensing aggregate(s) downwardly from a hopper and simultaneously dispensing the cement particles from a tube within the aggregate hopper above the hopper opening. The cement particles adhere to moisture on the surface of the aggregate(s).

Abstract: An automatic cementing system and method are disclosed for precisely controlling the density of a slurry during a continuously mixed cement application. The system includes an input water line and a dry cement hopper for supplying water and dry cement, respectively, to a mixing chamber. The mixing chamber includes two chambers, Chamber A and Chamber B, for thoroughly mixing the water and cement together to form a cement slurry. Chamber B includes a level sensor for measuring the change in slurry level. The input line includes a pump for supplying the water to the mixing chamber, and a flow meter for measuring the rate at which the water is supplied. Similarly, the hopper includes a rotary valve for regulating the rate at which the dry cement is supplied to the mixing chamber and a speed sensor for measuring the speed of the rotary valve. A discharge line with a discharge pump and a discharge flow meter receives and discharges cement slurry.

Abstract: In a concrete pump for wet spraying, in which standard concrete is pumped to a mixing jet, compressed air and if necessary a hardening accelerant are mixed into the concrete stream, which is applied with the jet and compressed; it is the purpose of the invention in its initial version on the one hand to minimize the fine dust yield at the jet, on the other hand to guarantee the availability of the amount of compressed air needed for the wet spraying process, characterized by a regulating section (20) in which the capacity of the concrete pump (1) forms a standard volume for monitoring the amount of compressed air flowing to the mixing jet (3) in such a way that the relationship of the amount of compressed air mixed in per unit of time to the amount of concrete pumped in per unit of time corresponds to a desired value which produces the smallest fine dust yield when the concrete is applied.

Abstract: An automatic cementing system and method are disclosed for precisely controlling the density of a slurry during a continuously mixed cement application. The system includes an input water line and a dry cement hopper for supplying water and dry cement, respectively, to a mixing chamber. The mixing chamber includes two chambers, Chamber A and Chamber B, for thoroughly mixing the water and cement together to form a cement slurry. Chamber B includes a level sensor for measuring the change in slurry level. The input line includes a pump for supplying the water to the mixing chamber, and a flow meter for measuring the rate at which the water is supplied. Similarly, the hopper includes a rotary valve for regulating the rate at which the dry cement is supplied to the mixing chamber and a speed sensor for measuring the speed of the rotary valve. A discharge line with a discharge pump and a discharge flow meter receives and discharges cement slurry.

Abstract: A roadworking machine can be converted from front load road planing capability to cold in-place recycling capability by replacing the secondary conveyor on the front end of the machine with a mixer such as a standard pugmill. The machine can be converted in the field simply by detaching the conveyor from a-mounting assembly on the chassis and by attaching the pugmill to the same mounting assembly. The conveyor and pugmill are preferably attachable to the mounting assembly so as to be pivotable with respect to the chassis about both vertical and horizontal axes. The machine as thus constructed permits considerable versatility in both the discharge of milled materials from the secondary conveyor during front load planing and the discharge of recycled materials from the mixer during cold in-place recycling.

Abstract: An automated density and chemical controller automatically controls the density and chemical proportions of a slurry that is injected into a well during a well fracturing operation. The automated density controller receives from the operator the parameters of the fracturing operation and automatically controls the addition of a proppant to water to produce a slurry with a desired density. The automated density controller measures the incoming flow of water into a blender tub and regulates the delivery of proppant in the blender tub to produce a slurry of the desired density. The performance characteristics of the mechanism used to deliver the proppant are programmed into the controller to enable the controller to regulate the quantity of proppant delivered by controlling the operational speed of the delivery mechanism. The automated chemical controller regulates the addition of chemicals based on the incoming flow rate.

Abstract: An automated density and chemical controller automatically controls the density and chemical proportions of a slurry that is injected into a well during a well fracturing operation to produce a slurry with a desired density. The automated controller automatically controls the addition of a proppant to water based on the parameters of the fracturing operation, the incoming flow of water into a blender tub, the incoming flow rate of chemicals, and the performance characteristics of the mechanism used to deliver the proppant. The automated density controller also measures the flow of the slurry discharged from the blender tub and calculates the actual density of the slurry. After comparing the calculated actual density with the desired density, the automated density controller calculates a correction factor and recalibrates the performance characteristics of the proppant delivery mechanism. The automated density controller also includes a densiometer for measuring the actual density of the slurry.

Abstract: Apparatus and methods for mixing plastic materials having different densities to supply a substantially uniform quantity of the mixture of such materials to an extruder or other processing machine. The mixture of materials is fed forcibly from the mixer to the processing machine by a variable speed auger. The mixture exerts a reactive force on the auger commensurate with the bulk density of the mixture. A sensor detects variations in the reactive force and produces signals which adjust the rate of rotation of the auger in inverse relation to the variations in the bulk density of the mixture to maintain the quantity of the mixture discharged from the mixer per unit of time within a selected range.

Abstract: A portable system for on-site batch mixing of cementitious materials, such as mortar and grout, includes a batch mixing machine for metering and mixing cement, sand and water, a cement storage silo sized to hold at least one commercial delivery truckload of cement, and a pair of sand supporting ground pads. The large cement storage silo significantly reduces the manpower and equipment costs associated with the overall batch mixing process, and the sand support pads operate to prevent dirt contamination of the cementitious mixture. The water storage portion is provided with a simplified, floatless fill level control system and an improved water heating system which significantly reduces water temperature stratification. A specially designed pressurized shaft bearing/seal structure provided on the batch mixer portion of the mixing machine reduces grease and seal maintenance and functions to essentially preclude entry of cementitious material into the shaft bearing.

Abstract: The apparatus is capable of supplying curds continuously, and comprises: a horizontal channel with a tapered bottom, having a feeding auger arranged in the bottom and actuatable by motor means; several cradles with semicircular section, rotatably carried in a horizontal position in the channel above the auger, and having a diameter slightly less than the distance between opposite walls of the channel, and actuatable by actuator means to take a first position with their mouths looking upwards and a second position with their mouths looking downwards; and several cheesemaking tipping vats arranged side-by-side with the channel and adapted to pour curds into the cradles while the latter are in their first position.

Abstract: The invention discloses an apparatus for the preparation and distribution of dye solutions to a dyeing apparatus or to a color kitchen, including a unit for the loading of powder-dye into dissolution vats, a collector unit for conveyance of the dye solution to a distributor unit and for pipe flushing, and a distributor unit. The collector unit consists of a selection-plate, which alternatively connects the distributor unit with the dissolution vats or with a flushing water-network, wherein the distributor unit consists of a plurality of outlets supplied by the collector unit, through a rotary collector, the outlets being connected with the dyeing equipment or with the color kitchen, or with sewers.

Abstract: An aerated cementitious composition is produced by feeding a mixture comprising cement and foaming agent to a mixing chamber open to atmosphere together with a feed of liquid. The ingredients are mixed and the wetted mixture pumped to a desired site, the capacity of pumping being greater than the feed rate of the ingredients into the mixing chamber such that air is drawn into the mixing chamber.

Abstract: A measuring mixer for use with either liquids or powders in which different supply systems supply different stock liquids or powders to a receiving container from supply containers. A continuously variable flow regulator is associated with each supply container. The cumulative weight of the receiving container is measured and compared with a target weight. Then a computation section calculates a desired flow rate based upon both the deviation from the target weight and a time variation thereof. This calculation is preferably done according to fuzzy inference. The desired flow rate is then used to control a selected one of the flow regulators so that the measurement is sequentially performed between supply systems. Optionally, the receiving container can be movable between the different supply systems.

Abstract: A dispensing apparatus is located in the rear of a tip truck body. When the tipping body of the truck is inclined gravity causes bulk material held in the tipping body at either side of a partition to feed augers. The dispensing apparatus includes at least one tank preferably a central tank holding powdered material such as cement powder dispensed through a chute by virtue of a paddle wheel dispenser. Water tanks which dispense water through an outlet are located at either side of the cement powder tank. A common drive shaft drives the augers and the paddle wheel. The dispensing of material is controlled by controllers such that a predetermined ratio of material can be dispensed into, for example a mixer. The dispenser can be used for dispensing the constituents of concrete and may be removable from the tip truck body so that the tip truck can function as a normal tip truck.

Abstract: An apparatus for preparing a mixture, such as mortar, with predetermined quantities by weight of the components, such as sand, cement and the like, a supply of which is present in container compartments 4, 5 of e.g. hopper 1. The container compartments are each connectable to a metering conveyor 11, 12 of the apparatus. The apparatus is further provided with a mixing vessel 13 having stirring means, the vessel being supported at least partly on force absorbers 14 of weighing means. The weighting means are coupled with control means 15 for successively putting into operation the metering conveyor means for the various components.

Abstract: An aerated cementitious composition is produced by feeding a mixture comprising cement and foaming agent to a mixing chamber open to atmosphere together with a feed of liquid. The ingredients are mixed and the wetted mixture pumped to a desired site, the capacity of pumping being greater than the feed rate of the ingredients into the mixing chamber such that air is drawn into the mixing chamber.

Abstract: A cement mobile mixer for mixing concrete from sand, aggregate, cement and water.

Abstract: Mixing apparatus is provided for the production of mixtures of particulate solids and in particular, for the production of various mortar mixtures. The apparatus includes metering means, control means and transfer means for metering out and introducing predetermined quantities of components into a mixer and thereupon, after mixing, delivering the mixed product into means for loading transportation vehicles. The apparatus has no intermediate containers for storing various mixtures of building materials. A mixer is provided which can be emptied residue-free. A self-cleaning conveying system from the mixer to each transfer device is further provided. The lower wall zone of the mixer can be completely opened for residue-free emptying, the opening angle being greater than the angle of slide of the mixing material or residues thereof in the mixer. Such an opening prevents appreciable residues from being left in the mixer and from contaminating subsequent mixtures.

Abstract: An apparatus for continuously blending a viscous liquid, such as hot asphalt, with particulate solids, such as ground rubber, includes a vertical cylindrical tank in which is disposed a smaller vertical vessel defining therein a blending chamber. Open lower side regions of the vessel feed the blended slurry to a holding chamber defined between the vessel and tank. A shaft rotatably mounted through the blending chamber has fixed thereto a blending disc and two hollow blending cones coaxially mounted on opposite sides of the disc to form two shear-type blending regions. Hydraulically driven pumps and motors feed the viscous liquid and solids to the blending chamber, rotate the blender shaft and withdraw slurry from the holding region for use. Hydraulic flow control valves enable selectively variable feeding, blending and slurry discharge rates. The relative feed rates of the liquid and solids are preferably continuously monitored to assure the desired liquid/solid blend ratio.

Abstract: A processing apparatus for sludge and liquid waste comprising a wheeled vehicle having a frame, a drum type mixer mounted for rotation on said frame, motive power means including a hydraulic pump, a hydraulic motor for rotating said drum type mixer mounted on said frame operable in response to output from said hydraulic pump, waste feed means mounted on said frame, a hydraulic motor for said waste feed means on said frame operable in response to the output of said pump for feeding waste into the input end of said mixer, storage means on said frame for storing a supply of processing agent for said waste, processing agent feed supply means on said frame a hydraulic motor for said processing agent feed means on said frame operable in response to output of said pump for feeding processing agents from said storage means to said mixer, delivery means mounted on said frame for delivering output from said drum type mixer for conveyance to a remote location, valve control means for supplying output of said pump to sai

Abstract: The viscosity and amount of limestone in a limestone asphalt mixture (filled coating mixture) is determined sensing the density of the mixture which will indicate the percent of limestone in the mixture and also sensing the temperature of the mixture, and adjusting the ratio of limestone to asphalt to maximize this ratio relative to a pre-set ratio and adjusting the pre-set ratio in accordance with the temperature of the mixture when the temperature is below a pre-determined limit.

Abstract: A device for mixing mortar with a liquid or foaming material includes a reservoir for the dry mortar, a housing containing a portion of a driven shaft with the housing terminating at one end in a mixing chamber; the mixing chamber contains a disc attached to the shaft and rotatable therewith; on one side of the disc, there is located radially extending mixing paddles or blades, the outer edges of the blades and the discs being spaced a predetermined distance to define a gap between the inner surface of the wall of the mixing chamber and the outer edge of the blades and disc; at one end of the mixing chamber an outlet is provided which is connected to a suction device and a baffle ring is situated about the outlet to divert material away from the suction inlet.

Abstract: A foundry sand mixer for mixing and dispensing silica or green sand and their additives through the enclosed longitudinal belt conveyor mechanism having a plurality of openings in the top communicating with a first feeder disposed above the enclosed longitudinal belt conveyor mechanism and including a pair of openings in the bottom. The first feeder includes an auger-type conveyor and a sand weir communicating with the most upstream opening in the first feeder. A first hopper for containing silica sand and a second hopper for containing green sand are disposed over the first feeder. A selective valve is disposed at the bottom of each of the first and second hoppers permitting the flow of sand through only one of the hoppers at any time or preventing the flow of any sand from the hoppers.