Method and apparatus for logging earth boreholes. [in deviated wells]

Patent · Tue Aug 16 04:00:00 EDT 1977

OSTI ID:7294850

Angehrn, J A

A self-contained, battery powered well logging instrument is pumped down the interior of a drill pipe string having a catcher sub at its lower end. When the logging instrument latches into the catcher sub, the pumped fluid circulation is blocked, after which increased pump pressure switches a valve assembly to recreate circulation and energize the logging instrument to the standby position. An accelerometer in the logging instrument detects the upward movement of the instrument and switches the circuitry from standby to the record mode. The output from a clock controlled by the downhole accelerometer is recorded along with the logging information and is synchronized with pipe footage measurements and with a similar such accelerometer and clock at the earth's surface which are responsive to the movement of the pipe string at the earth's surface. The recorded logging samples are thus related to true depth by correlating with the data simultaneously recorded at the earth's surface. As an alternative embodiment, the logging instrument is attached to the drill pipe prior to running the pipe into the borehole.

• Assignee: Dresser Industries, Inc.
• Patent Number(s): US 4041780
• OSTI ID: 7294850
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020200 -- Petroleum-- Reserves
Geology
& Exploration
440400* -- Well Logging Instrumentation
47 OTHER INSTRUMENTATION
ACCELEROMETERS
CONTROL EQUIPMENT
DEPTH
DIMENSIONS
DIRECTIONAL DRILLING
DRILLING
DRILLING FLUIDS
EQUIPMENT
FLOW REGULATORS
MEASURING INSTRUMENTS
OFFSHORE DRILLING
TIME MEASUREMENT
VALVES
WELL LOGGING