초록 ▼

Disclosed is a safety system for well testing, utilizing a new and novel bleedoff tool in the subsea test tree handling string, which provides rapid pressure reduction in the handling string and assures mechanical disconnect of the subsea test tree if the test tree cannot be disconnected hydraulical

Disclosed is a safety system for well testing, utilizing a new and novel bleedoff tool in the subsea test tree handling string, which provides rapid pressure reduction in the handling string and assures mechanical disconnect of the subsea test tree if the test tree cannot be disconnected hydraulically. The bleedoff tool is operated and opened to bleed pressure from the handling string by applying a predetermined torque. This tool may be extended by pull to transmit higher than opening torque and will transmit torque after opening. The bleedoff tool contains an internal valve, which closes when the bleedoff tool is opened, and retains fluids in the handling string. The bleedoff tool operating torque values are not changed by high internal pressures or great axial tension or compressive loads on the tool.

대표청구항 ▼

A bleedoff tool, connectable in pipe and having a longitudinal flow passage comprising: (a) a piston; (b) a body, including upper and lower bodies rotatably mounted and sealed around and releasably pinned to said piston; (c) means for limiting body rotation relative to said piston to less than one t

A bleedoff tool, connectable in pipe and having a longitudinal flow passage comprising: (a) a piston; (b) a body, including upper and lower bodies rotatably mounted and sealed around and releasably pinned to said piston; (c) means for limiting body rotation relative to said piston to less than one turn; (d) pressure balanced areas on the piston for preventing extension of said piston from said body; (e) bearing means for minimizing relative rotational friction between the body and piston; (f) closed flow passage means, openable on relative rotation betwen the body and piston to permit flow from the longitudinal flow passage to exterior of the tool; (g) valve means in the longitudinal flow passage positioned open to permit two-way flow therethrough, said valve means releasable on a relative rotation between the body and piston to close and permit upward flow through said flow passage; (h) means positioning said longitudinal flow passage valve means open; and (i) friction means for transmitting torque through the tool.