Apparatus for well logging while drilling

Patent · Tue Sep 20 04:00:00 EDT 1983

OSTI ID:5718048

Mumby, E S

A monostable, solenoid-operated valve in a passage which bypasses the drilling fluid pressure drop across a drill bit at the lower end of a drill string in a well opens and closes in response to downhole conditions to create pressure pulses in the drilling fluid. The valve is urged toward a closed position by drilling fluid pumped through the drill string. A larger force is required to open the valve than to hold it open. Current supplied to the solenoid to open the valve is thereafter reduced to a value sufficient to hold the valve open. The solenoid is de-energized to close the valve.

• Assignee: Exploration Logging, Inc.
• Patent Number(s): US 4405021
• OSTI ID: 5718048
• 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
CONTROL EQUIPMENT
DRILLING FLUIDS
ELECTRIC COILS
ELECTRICAL EQUIPMENT
EQUIPMENT
FLOW REGULATORS
FLUIDS
MWD SYSTEMS
NATURAL GAS WELLS
OIL WELLS
SOLENOIDS
VALVES
WELL LOGGING
WELL LOGGING EQUIPMENT
WELLS