Subsurface chills to improve railcar knuckle formation
US9308578B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 21, 2011 |
| Grant date | Apr 12, 2016 |
| Priority date | — |
| Expiry date | May 25, 2032 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB61G7/00
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
A method for manufacturing a railcar coupler knuckle includes, before casting, positioning an external chill within a cope mold portion and a drag mold portion offset from and adjacent internal walls of a pulling face and a throat of the cope and drag mold portions, thus producing a casting with reduced micro-shrinkage in at least the throat, a high-stress section of the casting. Use of subsurface chills produces an improved surface with fewer inclusions when compared to an equivalent surface produced in a process without use of a subsurface chill. The external chill may be a cone chill of a larger size to improve cooling and solidification at and below the surface. The external chill may also be a cylindrical and/or oblong chill with a tapered design that may correspond to the internal walls of the cope and drag mold portions between the pulling face and the throat.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.