Abstract: Apparatus for the gravity-cast, “lost-foam” casting of metal castings, including a fugitive, pyrolizable foam pattern forming a casting cavity in a bed of loose sand, and a hollow sprue for supplying melt to the casting cavity, wherein the sprue consists essentially of the same metal as is being cast. A high-temperature, porous vent is provided adjacent the discharge end of the metal sprue to expel air from the sprue that would otherwise be trapped therein.

Abstract: A method for making sand particle foundry mold members. Sand particles are coated with an aqueous dispersion of a suitable binder material such as a gelatin gel. The moist gelatin coated particles are gravity fed into a pattern box for the mold member and subjected to multi-axis vibration to pack the sand in the pattern box. The moist sand is then heated with radio frequency energy to promote binder flow to the corners of the particles, and air flow is initiated to transport water from the mass of particles to harden the mass of particles into the mold member.

Abstract: A method is disclosed for making sand particle foundry mold members. Sand particles are coated with an aqueous dispersion of a suitable binder material such as a gelatin gel. The moist gelatin coated particles are gravity fed into a pattern box for the mold member and subjected to multi-axis vibration to pack the sand in the pattern box. The moist sand is then heated with radio frequency energy to promote binder flow to the corners of the particles, and air flow is initiated to transport water from the mass of particles to harden the mass of particles into the mold member.

Abstract: Apparatus for the gravity-cast, “lost-foam” casting of metal castings, including a fugitive, pyrolizable foam pattern forming a casting cavity in a bed of loose sand, and a hollow sprue for supplying melt to the casting cavity, wherein the sprue consists essentially of the same metal as is being cast. A high-temperature, porous vent is provided adjacent the discharge end of the metal sprue to expel air from the sprue that would otherwise be trapped therein.

Abstract: Apparatus for the gravity-cast, bottom-fill, “lost foam” casting of metal castings, including a fugitive, pyrolizable pattern (for forming a casting cavity), and a hollow sprue (for conducting melt to the casting cavity) embedded in a bed of loose sand. The sprue is free from pyrolyzable foam and conducts melt from above the pattern to a gating system supplying melt to the pattern. The sprue is constructed so as to cause the melt to approach the gating system from beneath and keep any pyrolysis products from entering the sprue.

Abstract: A two-chamber furnace for the low pressure countergravity casting of metal wherein the first chamber is a molten metal supply chamber connected by a submerged orifice closable by a stopper rod valve to a sealed second chamber that is pressurizable to fill a superjacent mold. The stopper rod valve is readily replaceable from the top of the furnace without having to empty the melt from the furnace.