Patent Application
20150151421
Systems that employ control lines through which pressure is supplied to pistons to actuate tools are in use in industries such as carbon dioxide sequestration and hydrocarbon recovery. Such systems are used to open safety valves by moving a flow tube thereby compressing a spring and opening a flapper, for example. These systems are fail safe since if the control line supplying pressure is breached energy stored in the spring moves the flow tube and piston thereby allowing the flapper to close. Such systems however are inoperable after such a failure has occurred. Industries are therefore receptive to new systems and methods that overcome the aforementioned limitation.
Disclosed herein is a control line operating system. The system includes a first piston having a first pressure face and a second pressure face, a first control line in operable communication with the first pressure face of the first piston, a second piston having a third pressure face and a fourth pressure face and a second control line in operable communication with the third pressure face of the second piston. Both the first piston and the second piston are in operable communication with a tool such that pressure increases in either the first control line or the second control line can cause actuation of the tool, the first control line is in operable communication with the fourth pressure face of the second piston and the second control line is in operable communication with the second pressure face of the first piston.
Further disclosed herein is a method of operating a tool. The method includes pressuring up one of a first control line, actuating the tool with the pressuring up, allowing the actuation of the tool to be reversed upon breach of the first control line, pressuring up a second control line and actuating the tool.
The following descriptions should not be considered limiting in any way. With reference to the accompanying drawings, like elements are numbered alike:
A detailed description of one or more embodiments of the disclosed apparatus and method are presented herein by way of exemplification and not limitation with reference to the Figures.
Referring to
In applications wherein the control lines 14, 24 are oriented vertically, such that hydrostatic pressure can build therewithin such as in the hydrocarbon recovery and carbon dioxide sequestration industries, for example, hydrostatic pressure is balanced across the pistons 18, 28. This hydrostatic balancing allows movement of the pistons 18, 28 at lower pressures in the control lines 14, 24 than would be needed if the hydrostatic balancing were not present.
Referring to
The check valves 112 and 116 can be configured similar to the valve 10 described in detail in copending U.S. patent application Ser. No. 13/737224, filed Jan. 9, 2013, the entire contents of which are incorporated herein by reference.
Referring to
The first fail safe mechanisms 222 of the illustrated embodiment includes a member 230 sealingly movable engaged within a housing 234 with ports 238 in fluidic communication with the first control line 14, the first pressure face 32 and the second pressure face 36. A differential area of the member 230 allows pressure from the second pressure face 36 to urge the member 230 against a biasing arrangement 240 (and weight of the member 240 if oriented vertically) to maintain fluidic communication of the first control line 14 with the first pressure face 32 through the ports 238 in the housing 234. Upon a drop of pressure, below a threshold value, in the second pressure face 36 the biasing arrangement 240 (and weight of the member 240 if applicable) moves the member 230 to a position wherein fluid communication between the first control line 14 and the first piston 18 is blocked and allows fluid communication between the first pressure face 32 and the second pressure face 36 thereby hydraulically balancing fluid forces across the first piston 18 allowing it to be easily moved by the force of the biasing member 54, for example. Although the embodiment of the first fail safe mechanism 222 illustrated is a valve, other embodiments can be in the form of other mechanisms.
The second fail safe mechanism 226 operates in a similar manner to that of the first fail safe mechanism 222, albeit in relation to the other of the control lines and the pistons and as such the details of its operation will not be repeated herein.
While the invention has been described with reference to an exemplary embodiment or embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof Therefore, it is intended that the invention not be limited to the particular embodiment disclosed as the best mode contemplated for carrying out this invention, but that the invention will include all embodiments falling within the scope of the claims. Also, in the drawings and the description, there have been disclosed exemplary embodiments of the invention and, although specific terms may have been employed, they are unless otherwise stated used in a generic and descriptive sense only and not for purposes of limitation, the scope of the invention therefore not being so limited. Moreover, the use of the terms first, second, etc. do not denote any order or importance, but rather the terms first, second, etc. are used to distinguish one element from another. Furthermore, the use of the terms a, an, etc. do not denote a limitation of quantity, but rather denote the presence of at least one of the referenced item.
