Patent · US Expired

PDF valve

US6547007B2 · kind B2 · utility

61Cited by
9References
27Claims
0Family size

Assignee

Inventors

Key dates

Filing dateApr 17, 2001
Grant dateApr 15, 2003
Priority date
Expiry dateApr 17, 2021

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B2200/05
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A differential float and cementing valve assembly used to position and cement casing in a well bore. A leaf spring and other components of the assembly are preferably constructed of composite materials and/or plastics that can be drilled up with polycrystalline diamond compact (PDC) bits.

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