Method for circulating and maintaining drilling mud in a wellbore

Patent · Tue Mar 31 04:00:00 EST 1987

OSTI ID:6605149

Johnson, A S

A method is described for circulating and maintaining a drilling mud in a wellbore at a desired pressure during drilling operations, the wellbore being drilled into a subterranean formation from a subterranean access cavity. The method consists essentially of: (a) circulating the drilling mud from a first supply of drilling mud located in the access cavity through a drill pipe in the wellbore into the wellbore, maintaining a desired pressure in the wellbore and recovering the drilling mud from the wellbore at a controlled rate using a mud pump and mud pit arrangement located in the access cavity; and, (b) maintaining a second supply of drilling mud, the second supply of drilling mud being located at the surface, in fluid communication with the drill pipe at a suitable pressure so that when the mud pump fails to maintain pressure in the drill pipe, drilling mud is supplied from the second supply of drilling mud to maintain pressure in the drill pipe. The pressure in the drilling mud from the second supply is maintained by the hydrostatic pressure resulting from the density of the drilling mud and the height of the column of drilling mud extending from the subterranean formation to the surface.

• Assignee: Atlantic Richfield Co., Los Angeles, CA
• Patent Number(s): US 4653597
• OSTI ID: 6605149
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
CIRCULATING SYSTEMS
CONTROL
DENSITY
DRILL PIPES
DRILLING
DRILLING EQUIPMENT
DRILLING FLUIDS
EQUIPMENT
FLUIDS
HYDROSTATICS
NATURAL GAS WELLS
OIL WELLS
PHYSICAL PROPERTIES
PIPES
PRESSURE CONTROL
WELL DRILLING
WELLS