Patent · US Expired

Vacuum bore chill for lost foam casting

US4969505A · kind A · utility

5Cited by
7References
3Claims
0Family size

Assignee

Inventor

Key dates

Filing dateDec 21, 1989
Grant dateNov 13, 1990
Priority date
Expiry dateDec 21, 2009

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB22D27/15
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

A vacuum chill device is provided for reducing porosity in a bore wall of a lost foam metal casting. In a preferred embodiment, the chill device is attached to a vaporizable pattern formed of polystyrene or the like and includes a vacuum chamber received in a bore defined by the pattern. The pattern and chill device are embedded in a body of unbonded sand particles or the like, whereupon the refractory body extends therebetween. The vacuum chamber is connected to a vacuum line that leads outside the mold and includes screened orificies through which the vacuum chamber communicates with the surrounding refractory body. During casting, pattern decomposition vapors venting into the bore are drawn through the orifices into the vacuum chamber and exhausted through the vacuum line. Removal of the hot vapors from the bore by the vacuum device accelerates solidification of the bore wall to reduce shrink porosity therein.

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