Apparatus and method for logging wells while drilling

Patent · Tue Mar 25 04:00:00 EST 1986

OSTI ID:5624768

Macleod, N C

This patent describes an apparatus and method for logging wells while drilling for detecting electrical data reflective of geological conditions generally ahead of a drill bit in a well and communicating such data to ground surface via an electrically conductive drill string. This apparatus consists of: excitation source means for inducing alternating electrical excitation currents to flow through earth strata surrounding the drill bit; an elongated, electrically conductive, cylindrical module forming a drill collar means connected in the drill string proximate the drill bit at the lower end of the drill string; a bi-directional remote coupler including, an electrically conductive cylindrical coupler housing forming a part of the conductive drill string above the module; a remote relay toroidal transformer means encircling a cross-sectional area coaxially within the coupler housing and having one lead of its toroidal winding electrically connected to the coupler housing; an insulated conductor of predetermined length electrically connected between the other lead of the toroidal winding and a wiper contactor contacting the module at a point below the first signal coupling means, the first signal coupling means inducing the data signals in the insulated conductor, the conductor communicating the data signals to the remote relay toroidal transformer means which in turn couples the data signals into the drill string.

• Assignee: MacLeod Lab., Inc., San Jose, CA
• Patent Number(s): US 4578675
• OSTI ID: 5624768
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200* -- Petroleum-- Reserves
Geology
& Exploration
03 NATURAL GAS
030200 -- Natural Gas-- Reserves
Geology
& Exploration
440400 -- Well Logging Instrumentation
47 OTHER INSTRUMENTATION
ALTERNATING CURRENT
CURRENTS
DATA TRANSMISSION SYSTEMS
DESIGN
DRILL BITS
DRILL PIPES
DRILLING EQUIPMENT
ELECTRIC CONDUCTIVITY
ELECTRIC CURRENTS
ELECTRIC LOGGING
ELECTRICAL EQUIPMENT
ELECTRICAL PROPERTIES
ENERGY-LEVEL TRANSITIONS
EQUIPMENT
EXCITATION
MWD SYSTEMS
NATURAL GAS WELLS
OIL WELLS
PHYSICAL PROPERTIES
PIPES
RELAYS
SIGNALS
TRANSFORMERS
WELL LOGGING
WELLS