Abstract:
Apparatus for the countergravity, shell-mold casting process comprising a gas-permeable shell mold sealed in the mouth of a vacuum chamber and a hollow, expendable, gas-permeable, thermally degradable, core disposed with the molding cavity for engulfment and retention by the metal being cast. The core defines a central evacuation cavity and an unobstructed vent for exhausting the evacuation cavity into the vacuum chamber such that the pressure in the evacuation cavity is substantially equal to that in the vacuum chamber during casting.
Abstract:
Apparatus for the vacuum countergravity casting of metal including an elastomeric sealing gasket substantially thermally insulated, conduction-wise, from the underlying melt's heat by the mold-forming material and shielded from the melt's radiant heat by a surrounding skirt depending from the vacuum box.
Abstract:
A mold temperature control system comprises a mold section having a cavity, a fluid circuit to distribute a flow of a conditioning fluid, the fluid circuit being positioned spaced apart from the cavity, a temperature sensor positioned in the mold to generate a signal representative of a temperature in the mold, a controllable supply of the conditioning fluid, and a controller for automatically initiating flow of the conditioning fluid through the fluid circuit in response to an initiation temperature and for automatically terminating flow of the conditioning fluid through the fluid circuit in response to a termination temperature.
Abstract:
A method for producing a sand core includes the following steps: (a) providing a casting mold having a mold cavity, the casting mold including at least one first conduit and at least one second conduit; (b) providing a sand core disposed in the mold cavity; (c) providing a supply of conditioning gas to the casting mold, the conditioning gas being supplied to the casting mold through at least one of the first and second conduits; (d) providing a controller connected to the first conduit and the second conduit to selectively control the supply of conditioning gas; (e) providing a gas exhaust unit operatively connected to the casting mold; (f) operating the gas exhaust unit to cause the conditioning gas to be moved through the sand core; and (g) removing the sand core from the casting mold.
Abstract:
A melt-out zinc core is coated with insulating mica material and a graphite release agent and supported within a die cavity of a high pressure squeeze casting apparatus. Molten casting metal having a melting temperature above that of the core is injected into the die and then pressurized to about 15,000 psi to squeeze form the article in the die and around the core. The resultant article and core are then heated to above the melting temperature of the core and the core extracted from the article through cast-in outlet openings formed by the core. The insulating material and release agent are also extracted from the cast article by rinsing the cored passages of the cast article with water.
Abstract:
A method for metallurgically bonding a cylinder liner 22 within a clinder block 14 of an automotive engine includes coating the outer surface of the liner 22 with a low melting point molten metal coating material 24, such as a zinc, as well as cylinder walls of the block 14 and then allowing the coatings to solidify. The block 14 and liner 22 are then heated to an elevated temperature and the liner 22 press-fit into the block 14. This causes the coating materials to alloy with the liner and block metal as well as one another, forming a metallurgical bond between the block 14 and liner 22 when cooled.
Abstract:
Apparatus for the vacuum, countergravity casting of metal in shell molds including a gas permeable shell mold secured to the mouth of a vacuum box by a plurality of keepers on the ends of rotatable shafts reciprocably slidable through the ceiling of the vacuum box, which keepers are adapted for insertion into and rotation within an anchoring cavity in the mold such that the keeper engages a portion of the mold overhanging the cavity to secure the mold to the box.
Abstract:
Apparatus for the vacuum countergravity casting of metal in shell molds including a gas-permeable upper shell mold portion secured to a bottom mold portion and together secured to the mouth of a vacuum box by a plurality of threadable mounting sites engaged by self-tapping threads on the ends of rotatable shafts reciprocally slidable through the ceiling of the box. Each shaft has a stop fixed thereto at a predetermined distance above the threads for pressing the upper shell mold portion into sealing engagement with the bottom mold portion in order to eliminate the need to glue the upper and lower mold portions together.