Patent · US Expired

Foundry process including heat treating of produced castings in formation sand

US4222429A · kind A · utility

25Cited by
27References
28Claims
0Family size

Assignee

Inventor

Key dates

Filing dateJun 5, 1979
Grant dateSep 16, 1980
Priority date
Expiry dateJun 5, 1999

Classification

  • Technology area (CPC C)Chemistry; Metallurgy
  • CPC primaryC21D1/62
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

Castings are produced in a bed of production sand susceptible to both fluidizing and vacuumizing. The use of a vacuum at the time the molten metal is poured permits the use of thin shell molds made around styrene patterns, the vacuum maintaining mold shape and drawing out gases produced by the vaporizing pattern and otherwise. The produced casting is rapidly cooled in the bed while it is fluidized, the fluidized sand achieving good heat conduction. The casting is then heat stabilized while the bed is defluidized, the bed then becoming a good insulator. An austempering curve can be followed, thereby having the effect of heat treating in the same bed as used for casting production.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.