Patent · US Expired

Controlled directional drilling system and method

US4991668A · kind A · utility

42Cited by
4References
38Claims
0Family size

Assignees

Inventors

Key dates

Filing dateFeb 6, 1989
Grant dateFeb 12, 1991
Priority date
Expiry dateFeb 6, 2009

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B47/022
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A system of apparatus for the controlled directional drilling of a deviated well bore into the earth has a fluid operated drilling motor and drill bit secured on the bottom end of a drill string. The drill bit is supported for angular drilling relative to a substantially vertical well bore by either using a bent sub for supporting the drilling motor or by using a drilling motor with a bent housing or a combination of the two. A bypass tool is connected to the bent sub or motor housing, an orienting sub and mule shoe keying sub are connected to the bypass tool, and a surveying tool is connected in the drill string above the orienting sub and mule shoe sub. The bypass tool is in fluid connection with the motor and has a telescopic housing and a valve for circulating fluid into the bore hole to flush cuttings and debris therefrom. The surveying tool determines and controls the direction of drilling. The orienting sub and mule shoe keying sub orients the position of the motor and drill bit in relation to the surveying tool.

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