OIL WELL Russian patent published in 2009 - IPC E21B43/12 E21B33/03 

FIELD: oil-and-gas production.

SUBSTANCE: invention relates to exploitation of oil fields, and can be particularly used for remote, automatic and manual control of actuating mechanisms of well shutting-off devices. The well has a production casing with a flow column with underground production equipment, containing at least a circulating valve, shear valve, non-freezing check valve and, if necessary, a separating device, meant for separating oil and water. There is also a remote controlled device for cutting off flow of oil, which has an actuating mechanism, a wellhead with wellhead equipment, with a casing head, a tubing head, on which an X-mas tree is mounted, which includes shutting-off devices - casing and wing valves with actuating mechanisms, as well as a throttle valve adjacent to the latter, which regulates well flow rate and has an actuating mechanism, and monitoring and control devices - a fuse link and a low- and high-pressure control valve. The well is connected to a station for controlling shutting-off devices, throttle valve and cut off device, which comprises a pump-accumulator unit and at least one control unit per well. The pump-accumulator unit comprises a group of pumps and a high-pressure power functional hydropneumatic accumulator, connected to it through actuating medium of a high-pressure line. The control unit comprises power lines for functional control of actuating mechanisms of shutting-off devices, throttle valve and cut off device, where the said power lines are supplied by the said high-pressure line through pressure regulators, which reduce functional pressure to the required value. There is also a logical control line, which controls operation of actuating mechanisms through a time-stepped system for delaying command transmission for at least shutting-off the well in the logical sequence: wing valve - casing valve - cut off device. This line is connected to the fuse link and low- and high-pressure control valve and is fitted with hydraulic distribution valves with possibility of backing up command transmission for well shutting off. One of these valves can transmit a well shut-off command to the logical control line from the fuse link, the other - from the low- and high-pressure control valve, and at least two others - from remote and manual control respectively. The said delay system comprises delay mechanisms, fitted on sections for interaction of the logical control line with power lines for functional control of actuating mechanisms of the casing valve and cut off device. The delay mechanisms comprise a control hydropneumatic accumulator and a throttle, which provide for well shut-off at different times. The power line for functional control of the actuating mechanism of the throttle valves is provided with a three-position distribution valve, preferably with two electromagnets.

EFFECT: more reliable and accident-free operation of an oil well, reduced cost of oil extraction and much easier control of processes.

16 cl, 3 dwg