Abstract: An improvement in a process for making a mold for metal casting by applying a fluid ceramic composition containing binding agent and finely divided refractory substance to a pattern and hardening the same, which improvement comprises employing a ceramic composition which contains special solvents, anti-setting and thixotropic agents, so that this composition after applying gives a uniform coat which does not run down from walls.

Abstract: A method of making a number of foundry cores serially in which a foundry aggregate mixed with a curable binder is introduced into a core box cavity to form each green core which is gassed by passing into it a predetermined dose of a saturated vapor under pressure of a normally liquid curing agent for the binder and an inert carrier gas and then a purging gas is passed through the core to drive out unreacted curing agent. A ready supply of a saturated vapor of the curing agent is provided in a generating vessel. Once a body of the active liquid substance and overlying atmosphere of vapor is established in the generating vessel, the vapor is dispensed intermittently to the core box cavity in a series of bursts, one for each core gassed. Simultaneously with the dispensing of each burst, carrier gas is bubbled under pressure into a bottom zone of the vessel in minute bubbles so as to provide saturated vapor, replacing that dispensed.

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: In the production of foundry mold parts by the method described in U.S. Pat. No. 3,739,834, the production rate is increased by employing a foundry sand mix which can be cured by means of a gaseous curing agent and carrying out curing of the pressed mold part while the mold part is supported at the pressing station.

Abstract: A method of forming a metal oxide barrier layer at the interface between a refractory oxide-silica investment mold and a contained metal superalloy includes the firing of the mold or the mold-metal system, in a controlled prevailing atmosphere having a predetermined amount of oxygen therein. The barrier layer enables directional solidification of the contained superalloy at elevated temperatures to occur without metal-mold reaction.

Abstract: Automatic molding apparatus to make flaskless molds from match plate patterns using sand and binder pre-mix and an activator or catalyst includes form boxes having open faces and double wall construction with a continuous chamber between the walls. The inner wall is vented to the chamber to provide a gas flow passage. The apparatus also includes manifolds which clamp over openings in the top and bottom walls for innoculation and pneumatic withdrawal of activating or catalytic-reacting gases such as hot air or carbon dioxide which are innoculated at an innoculation station into the mold box to decrease the hardening time of the sand. The open faces of the mold box are closed by hinge plates or cover plates each rotated by a rack and pinion. The plates are further secured during sand filling by spring-loaded arms bearing against tapered ribs on the hinge plates.

Abstract: A method for producing cores and foundry moulds.The method is characterized in that foundry sand, a binder, and a low temperature reaction agent are mixed in a controlled atmosphere, and in that the mixture is maintained under these low temperature and controlled atmosphere conditions until it is introduced into the core box, the temperature and atmospheric control are then eliminated and the temperature raised slightly if necessary.

Abstract: Foundry moulds or cores are made by putting a mixture of foundry sand and acid-hardenable binder into a mould or core box, hardening the binder by passing an acidic gas through the mixture, removing the mould or core from the box and applying to its surface a material which will neutralise or adsorb acidic gases. The neutralising or adsorbent material permits avoidance of the health hazard of emission of acidic gas from the mould or core on storage or during use.

Abstract: The apparatus comprises high pressure injection means for supplying during an accurately adjustable controlled cycle time an accurately adjustable controlled volume of atomized cold set catalyst into a high pressure dry air, nitrogen and/or CO.sub.2 gas stream passing through the core box to cure the resin followed by a continuing air, nitrogen or CO.sub.2 gas purging of the core box. The fumes from the core box are drawn through a natural gas or propane fired fume incinerator wherein an excess air-fuel mixture causes oxidation of the fumes during a controlled temperature and residence time. The fume incinerator operates continuously at a constant temperature under control by an automatic temperature sensor regardless of fume input and includes suction means to prevent back flow of gasses from the incinerator to the core box.