Abstract: A method and composition for forming a dry free-flowing particulate solid is disclosed which utilizes a novel binder system for bonding particles of carbon, sand and/or other solid aggregate materials. The solid, non-sticky binder system comprises furfural, a phenolic novolak resin, and a liquid amine having free hydrogens on the amine nitrogen which is capable of reacting with furfural. This system is capable of adhering to such particles while retaining the free-flowing characteristics of the particles. The method involves mixing the aggregate with the furfural-phenolic novolak resin until tacky, and adding methylene chloride to the tacky mix while continuing to mix. The mix is cooled by the rapid evaporation of the methylene chloride and quickly forms the free-flowing characteristics of a powder or granulated material.

Abstract: A blow-moulding machine comprises a mixer for mixing refractory particles with a binder and a hardener or the like, a main tank for transporting moulding sand, a booster provided subsequently to said tank, a blast hose, and a blowing nozzle mounted at the tip end of said hose.

Abstract: A foundry composition adaptable to forming cores and molds comprising a foundry aggregate, a binder therefor, a catalyst and an amine, the binder being a substituted phenol.

Abstract: A granular composition is provided that is especially useful for the preparation of foundry cores and molds. Incorporated in the composition is a novel resin binder that imparts rapid curing properties to the composition.

Abstract: A pattern holder 12 and a sand tank 14 are rotatably mounted on a frame 16 so that the pattern holder can be inverted over and sealably mounted atop the sand tank. A vented pattern 26 is secured to the pattern holder and forms a first chamber between one side of the pattern and the interior of the pattern holder. A second chamber 90 is formed between the other side of the pattern and the interior of the sand tank when the pattern holder adjoins the sand tank. O-ring seals 32 and 80 isolate the chambers from the atmosphere so that a partial vacuum can be formed therein. A mixture 84 of sand and a gas-curable binder is provided in the sand tank so that the mixture will fall onto the pattern upon inverting the sand tank over the pattern holder. A flexible line 42 is provided for controllably introducing a gas catalyst into the chamber 38 in order to cure a portion of the sand-binder mixture to form a shell mold 94 of a predetermined thickness on a pattern face 36 of the pattern.

Abstract: A process is disclosed for curing a sand-furan resin mixture used in foundry practice to form cores and molds by the use of sulfur dioxide gas without forming sulfuric acid. Curing occurs when the furan resin, that is one containing a predominant amount of a furan moiety, is intermixed with a minor amount of a diisopropylbenzene monohydroperoxide (DIPBMHP) or diisopropylbenzene dihydroperoxide (DIPBDHP), or a mixture thereof. In addition to reacting with gaseous sulfur dioxide without forming sulfuric acid, these specific alkaryl hydroperoxides of which the monohydroperoxides have at least one alkyl ring substituent, have the peculiar characteristic of curing the resin in such a way that the DIPBMHP or DIPBDHP moiety becomes chemically bound in the cured resin. The result is a cured core or mold having a novel composition and superior physical properties compared to prior art cores and molds made with furan resins, in which the reaction with sulfur dioxide produces sulfuric acid.

Abstract: A process for producing hollow items, for instance foundry cores by reacting a catalyst gas with binder coated on mineral granular material includes providing a core box having a pattern formed of microporous material and investing binder-coated granular material into a volume defined by the pattern. The core box is then sealed so that the volume encloses a gas, for instance air at atmospheric pressure, within the granular material. A catalyst gas is applied at a predetermined pressure through the pattern so that the catalyst gas exerts a uniform pressure from the interior surface of the pattern against the enclosed air volume. The catalyst gas will penetrate a distance through the granular material for curing same determined by an equilibrium condition being reached between the applied catalyst gas pressure and air pressure which results from contraction of the volume.

Abstract: Improvements in molded articles from sinterable particulate solids, improvements in method for making such articles, and novel sacrificial binders for use in making such articles are disclosed. The sacrificial binders used in this invention comprise block polymers having the structural formulaX--[B (AB).sub..eta. A].sub..eta.'wherein "X" is a linking group, A or B, ".eta." is 0 or a positive integer, ".eta.'" is a positive integer greater than 2, "A" is a linear or branched polymer that is glassy or crystalline at room temperature and has its softening point in the range of about 80.degree. C. to about 250.degree. C. and "B" is a polymer different from A that behaves as an elastomer at processing temperatures, a plasticizer which may be oil, wax or oil and wax, and optionally other components.

Abstract: A resin for coating sand and a resin-coated sand produced therefrom wherein the resin is prepared by incorporating furan into a phenolic novolak resin. In the preferred practice, the resin is produced by reaction of furfuryl alcohol with a phenolic compound at an acid pH to give a furfuryl-phenolic intermediate in a first step, and then, in a second step, reacting the furfuryl-phenolic intermediate with a lower aliphatic aldehyde to produce the resin. The resin-coated sands of the present invention provide unexpectedly improved shakeout and collapsibility characteristics in the shell process.

Abstract: Apparatus for making shells from thermosetting liquid compounds in which at a first station, a travelling and heated permanent metal mould becomes filled with a thermosetting liquid compound. The mould is then moved to a second station where it is held until a shell wall of desired thickness is obtained. Thereafter, the mould is transferred to a further station where excess thermosetting compound is recovered and dispensed to an accumulative mixer to be used again. Subsequently, the metal mould is passed to a final station where it is opened and the ready shell removed. The apparatus comprises said and liquid constituent containers, a sand feeder and two mixers, namely, a basic mixer and an accumulative mixer. The apparatus is provided with a unit for proportioning the liquid constituents and a delivery unit to force the compound into the mould.

Abstract: A program controlled customized method for making molds comprises the steps of dispensing a layer of molding material including a mixture of sand and binder over a mold forming pattern by means of relative movement between a dispensing device and the pattern while selectively varying the ratio of sand and binder in the mixture dispensed in predetermined areas of the pattern or in successive layers to provide a mold of the desired strength in certain critical areas while conserving the amount of binder needed for the completed mold.

Abstract: Compositions which are useful for binding solid, discrete particles are comprised of a liquid one-step phenol formaldehyde resin, a urea resin component such as urea formaldehyde, an accelerator selected from an acid and a salt of an acid, and an aqueous emulsion of polyethylene. The wet mixtures of the foregoing components exhibit improved flow characteristics in intricate molds. The wet mixtures are useful for molding foundry core compositions and consolidated wood compositions that have improved moisture resistance.

Abstract: A stronger, thinner shell mold suitable for making cast metal parts comprises a base member of resin bonded sand and a second surfacing layer of a cured thermosetting binder material. Also disclosed is a method for forming the new shell mold.

Abstract: An improved method of forming a shell mold for casting having a shrink bob is provided. A tubular frusto-conical shrink bob, or riser, is first formed from sand and a plastic or resin binder such that both the apex and base of the riser are open. The riser is then inverted and positioned on a casting pattern with the apex of the riser abutting against the casting pattern. The entire pattern is then cast with a thermosetting material, such as sand and a binder, such that the thermosetting material bonds to both the pattern and the riser. After hardening, the thermosetting material with the attached riser forms a shell mold which is subsequently utilized in a foundry casting operation.

Abstract: An apparatus and method for forming foundry cores and molds of superior hardness and uniformity in a wide range of sizes includes staging hoppers for storing a first mass of sand coated with a catalyst-polymerizable resin film, and a second mass of sand coated with a catalyst film for polymerizing the resin. In forming the cores or molds these masses are simultaneoulsy and evenly dispersed into a high velocity carrier air-sand stream and directed through a static mixer, wherein the resin and catalyst-coated sand particles are intermingled and at least a partial integration of the films takes place, into a shaping mold cavity, wherein the sand mixture hardens into a desired shape.

Abstract: An apparatus and method for forming foundry cores and molds of superior hardness and uniformity in a wide range of sizes includes staging hoppers for storing a first mass of sand coated with a catalyst-polymerizable resin film, and a second mass of sand coated with a catalyst film for polymerizing the resin. In forming the cores or molds these masses are simultaneously and evenly dispersed into a high velocity carrier air-sand stream and directed through a static mixer stage, wherein the resin and catalyst-coated sand particles are intermingled and at least a partial integration of the films takes place, into a shaping mold cavity, wherein the sand mixture hardens into a desired shape. Because the process is fast and continuous and mixing is accomplished without mechanically driven mixing elements, the apparatus and method are particularly well suited to high volume foundry operations wherein resin-catalyst systems having very fast hardening times are utilized.

Abstract: An apparatus and method for forming foundry cores and molds of superior hardness and uniformity in a wide range of sizes includes staging hoppers for storing a first mass of sand coated with a catalyst-polymerizable resin film, and a second mass of sand coated with a catalyst film for polymerizing the resin. In forming the cores or molds these masses are simultaneously and evenly dispersed into a high velocity carrier air-sand stream and directed through a static mixer, wherein the resin and catalyst-coated sand particles are intermingled and at least a partial integration of the films takes place into a shaping mold cavity, wherein the sand mixture hardens into a desired shape. For improved integration of the resin and catalyst films, and for improved core density, air is injected into the air sand stream downline of the static mixer immediately prior to the sand mixture entering the shaping mold.

Abstract: An apparatus and method for forming foundry cores and molds of superior hardness and uniformity in a wide range of sizes includes staging hoppers for storing a first mass of sand coated with a catalyst-polymerizable resin film, and a second mass of sand coated with a catalyst film for polymerizing the resin. In forming the cores or molds these masses are evenly dispersed into a high velocity carrier air-sand stream and directed through a static mixer, wherein the resin and catalyst-coated sand particles are intermingled and at least a partial integration of the films takes place, into a shaping mold cavity, wherein the sand mixture hardens into a desired shape. Control circuitry is provided to independently control the dispersal of the catalyst and resin sand masses to enable the system to be fine tuned to produce cores of improved quality and uniformity.

Abstract: In foundry core-making or mold-making apparatus employing a rotary mixer working in a chamber and mixing together a sand-resin mix and a sand-catalyst mix to produce a cold quick-setting mixture that is then quickly discharged through the bottom of the chamber into a core-blower or molding machine, the chamber is fixed and has two separately movable sliding shutters controlling openings in its floor (it may be one long opening), one shutter controlling discharge into the blower or molding machine and the other controlling discharge of any residue to a waste chute. Preferably the first shutter uncovers a peripheral portion of the floor first, the discharge area thus growing from the periphery in a radial inward direction.

Abstract: A method and apparatus for preparing relatively large size foundry moulds and cores from cold-setting foundry sand mixtures wherein successive batches of sand and binder on the one hand with sand and catalyst on the other hand are mixed in a chamber having a rotary mixing element. The batches are discharged from the chamber by gravity into a mould or core box and the chamber is purged by a blast of compressed gas between the successive mixing operations.