A casting green sand mold comprising at least a pair of green sand mold parts each having a cavity portion, which are stacked with their cavity portions aligned to form a metal-melt-receiving cavity; each of the green sand mold parts being formed by casting sand containing a binder and water; a hardening-resin-based coating layer being formed on at least the cavity portion of each green sand mold part; the coating layer having gas-permeable pores having sufficient permeability to permit a gas generated by pouring a metal melt to escape; and a water content in a surface layer including the coating layer in a range from the cavity surface to the depth of 5 mm being smaller than that in the inner portion of the green sand mold.

The object of the present invention is to provide an embedding material composition for casting that makes it possible to conduct a favorable casting in the case where casting is conducted using a resin pattern that is different from a conventional wax pattern in disappearance temperature and disappearance behaviors through “rapid heating” excellent in treatment efficiency. The present invention relates to an embedding material composition for casting not using a heat-expandable refractory material as a main component, comprising: a binder; and a non-heat-expandable refractory material having an average particle diameter of 5 to 20 μm as main components, in which a content of the binder is 25 to 40 parts by mass and a content of the non-heat-expandable refractory material is 60 to 75 parts by mass in the case where the total amount of the main components is 100 parts by mass, and the present invention also relates to a casting process using the embedding material composition for casting.

The invention relates to a binder, which contains water glass and further a phosphate or a borate or both. The invention further relates to a method for constructing molds and cores layer by layer, the molds and cores comprising a construction material mixture, which at least comprises a refractory molding base material, and the binder. In order to produce the molds and cores layer by layer in 3-D printing, the refractory molding base material is applied layer by layer and is selectively printed with the binder layer by layer, and consequently a body corresponding to the molds or cores is constructed and the molds or cores are released after the unbonded construction material mixture has been removed.

The invention relates to a method for producing core sand and/or molding sand for casting purposes. A granular mineral mold base material is mixed with at least one inorganic binder and additionally an inorganic expanding additive. Water glass may be used as the binder and expandable graphite may be used as the expandable additive.

The invention relates to a method for producing core sand and/or molding sand for casting purposes. A granular mineral mold base material is mixed with at least one inorganic binder and additionally an inorganic expanding additive. Water glass may be used as the binder and expandable graphite may be used as the expandable additive.

A method of preparing a unique foundry premix composition that has a low bulk density of 30-45 lbs/ft.sup.3 and contains fine particles with an average particle size of 85-100 μm is described. The unique foundry premix composition is produced by using specially designed assemblies of mechanical equipment with improved efficiency so that the premix can be prepared at a site closer to a foundry. As a result, increase in premix density caused by handling and shipping across a long distance from a traditional premix manufacturing facility to a foundry can be suppressed; transportation cost can be saved; and safety would be of less concern. The use of the foundry premix composition to prepare a sand molding medium for casting molded articles is also described.

A high-temperature-resistant casting system comprises following casting elements in a connection relationship: a sprue cup (1) and a down sprue (2) connected with a lower end of the sprue cup, wherein the other end of the down sprue is connected with one end of a filtering element (6), the other end of the filtering element is connected with a three-way pipe (3), openings in two sides of the three-way pipe are connected with one end of an inlet section of a runner (4), and one end of an outlet section of the runner is connected with a tapered elbow (5). The casting elements comprise the following components in percentage by weight:41-51% of a refractory fiber, 40-51% of a silicate fiber and 5-19% of a binder. A preparation method of the high-temperature-resistant casting system is further provided.

The invention relates to a composition for forming a casting mold, the composition containing heat-resistant inorganic particles; a waterglass-based binder; a surfactant; a silicon-containing compound; activated carbon powder and grain; and water; and the silicon-containing compound contains at least one of metal silicon and ferrosilicon.

The invention relates to a composition for forming a casting mold, the composition containing heat-resistant inorganic particles; a waterglass-based binder; a surfactant; a silicon-containing compound; activated carbon powder and grain; and water; and the silicon-containing compound contains at least one of metal silicon and ferrosilicon.

What is described is a process for producing an article for use in the foundry industry, selected from the group consisting of molds, cores, feeder elements and molding material mixtures, comprising the following steps: (S1) producing or providing a binder system comprising the following components in three spatially separate vessels: a component (A) comprising particulate amorphous silicon dioxide, a first liquid component (B) comprising waterglass, and a second liquid component (C) comprising aluminate ions dissolved in an aqueous phase, (S2) contacting a mold base material (D) and constituents of all the said components (A), (B) and (C) of the binder system in predetermined ratios in one or more steps, so as to result in a molding material mixture in which the aluminate ions and the particulate amorphous silicon dioxide are mixed wholly or partly into the waterglass, wherein steps (S1) and (S2) are conducted in a facility for producing molding material mixtures. Also described are a corresponding molding material mixture and apparatuses and uses