Patent · US Expired

Floating sub

US4844181A · kind A · utility

48Cited by
8References
10Claims
0Family size

Inventor

Key dates

Filing dateAug 19, 1988
Grant dateJul 4, 1989
Priority date
Expiry dateAug 19, 2008

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B17/07
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A drill string is rotated by a top drive system and includes a floating sub which interconnects the upper end thereof with the drill pipe, and a bit at the lower end thereof. The bit is connected to the lower end of the drill pipe by means of a shock absorber. The floating sub prevents vibrational energy from the drill string from damaging the top drive system while the shock absorber prevents vibrational energy from damaging the bit and vice versa.

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