Inside blowout preventer well tool

Patent · Tue Oct 13 04:00:00 EDT 1981

OSTI ID:5919950

Miyagishima, T; Puntar, J; Wieveg, R

An inside blowout preventer well tool includes an elongated body threaded at both ends and including an axial opening. A flapper is pivotally mounted on a side of the opening and movable between a lower-open position and an upper-closed position. A downwardlyfacing valve seat is formed around the opening, the flapper engaging the seat in the upper-closed position. A spring urges the flapper toward the seat and a piston is movable in the opening between an upper position, where the lower end of the piston is above the valve seat, and a lower position, where the piston encases the flapper and holds it in the lower-open position. The piston is normally urged toward its upper position, the piston being shaped so that when the internal pressure of drilling mud normally circulating through the opening is greater by a predetermined amount than pressure outside the body, the pressure differential will overcome the force urging the piston upwardly and move the piston to the lower position. The piston is also responsive to fluid pressure outside the body so that the piston will automatically be moved to its upper position when the pressure differential is reduced by a predetermined amount.

• Assignee: Hydril Co
• Patent Number(s): US 4294314
• OSTI ID: 5919950
• Country of Publication: United States
• Language: English

Related Subjects

02 PETROLEUM
020300* -- Petroleum-- Drilling & Production
03 NATURAL GAS
030300 -- Natural Gas-- Drilling
Production
& Processing
04 OIL SHALES AND TAR SANDS
040300 -- Oil Shales & Tar Sands-- Drilling
Fracturing & Mining
BLOWOUT PREVENTERS
BOREHOLES
CAVITIES
CONTROL EQUIPMENT
CONTROL SYSTEMS
DESIGN
DRILL PIPES
DRILLING EQUIPMENT
EQUIPMENT
FLOW REGULATORS
FLUID FLOW
NATURAL GAS WELLS
OIL WELLS
PIPES
VALVES
WELLS