Extruded casing centralizer
US5937948A · kind A · utility
Inventor
Key dates
| Filing date | Jan 15, 1998 |
| Grant date | Aug 17, 1999 |
| Priority date | — |
| Expiry date | Jan 15, 2018 |
Classification
- Technology area (CPC E)Fixed Constructions
- CPC primaryE21B17/1042
- WIPO fieldCivil engineering
- WIPO sectorOther fields
Abstract
An integrally formed, solid casing centralizer for centering casing strings in oil and gas wells. The casing centralizer includes a central body having a bore adapted to closely engage a casing string and a plurality of integral blades radiating outwardly from the central body. The centralizer is formed by heating a billet of suitable metal to a temperature sufficient to render the billet malleable for extrusion yet which is substantially below a melting temperature of the billet, forcing the metal through a die, thereby forming a workpiece having a profile suitable to form a desired cross-sectional shape of a casing centralizer; cooling the extruded workpiece, and cutting the cooled, extruded workpiece into sections, each section having a length sufficient to form a casing centralizer. Each end of each blade may be bevelled to ease passage of the centralizer into the wellbore, and lock screws may be provided in threaded holes penetrating the central body and blades to fix the centralizers at desired locations on a casing string. The present invention results in an extruded solid casing centralizer substantially free of gas inclusions in the metal, resulting in high strength with m…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.