Patent · US Expired

Electromagnetic drilling apparatus and method

US4722402A · kind A · utility

56Cited by
13References
19Claims
0Family size

Inventor

Key dates

Filing dateJan 24, 1986
Grant dateFeb 2, 1988
Priority date
Expiry dateJan 24, 2006

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE21B10/38
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

Oil well drilling apparatus for drilling deep boreholes. The apparatus includes a high frequency, high voltage, AC generator at the surface of the ground which is connected to an electromagnetic hammer drill bit located at the bottom of the borehole. Electric current is conducted along a special drill string to the electromagnetic hammer drill located at the bottom of the hole. The drill string is a co-axial electrically conductive drill pipe which forms spaced annular current flow paths to the downhole electromagnetic hammer drill, while at the same time, drilling fluid flows along an axial flow path to the vibrating bit located at the bottom of the borehole. A special directional drill collar is positioned immediately above the electromagnetic hammer drill for controlling hole deviation. The co-axial electrically conductive lightweight drill pipe, the electrically conducting control deviation drill collars, and the electromagnetic hammer drill bit and pulse transformer each form a subcombination of the present invention; and, jointly comprise a new method and apparatus for forming boreholes.

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