Patent · US Expired

Drill pipe

US4949797A · kind A · utility

14Cited by
14References
16Claims
0Family size

Inventor

Key dates

Filing dateAug 24, 1989
Grant dateAug 21, 1990
Priority date
Expiry dateAug 24, 2009

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B17/22
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

An improved drill pipe assembly wherein each pipe section is formed as a concentric walled pipe having both an axial and an annular space therethrough, and the pipe section includes means for communicating the adjoining annular spaces through the series of respective box end/pin end joints whereby equipment compartmentation, conductor traverse, ballast containment, gas pressurization and weight addition can be effectively utilized in controlled manner.

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