Patent · US Expired

Apparatus for relaxing stresses at the end of oedometric compacting of a mixture of an aggregate and a binder

US4826419A · kind A · utility

4Cited by
4References
2Claims
0Family size

Inventors

Key dates

Filing dateJun 24, 1987
Grant dateMay 2, 1989
Priority date
Expiry dateJun 24, 2007

Classification

  • Technology area (CPC B)Performing Operations; Transporting
  • CPC primaryB30B11/027
  • WIPO fieldMachine tools
  • WIPO sectorMechanical engineering

Abstract

The invention relates to a process for relaxing lateral stresses at the end of shaping by compacting of a block constituted by an aggregate and a binder (such as a carbon-containing paste), to which is applied a main monoaxial stress in a rigid mold having a bottom and four side walls. According to the process, at the end of compacting and along the compacting axis, there is maintained a residual stress of between 50 and 2000 kilopascals, and preferably between 100 and 500 kilopascals. At least two of the side walls of the mold are then moved apart by a few millimeters, followed by the elimination of the main stress and the extraction of the molded block. The residual stress is maintained for a period of between 1 and 20 seconds following the moving apart of the walls.

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