Patent Application
20130327536
1. Field of the Invention
The present invention relates in general to mineral recovery wells, and in particular to an apparatus and method for sealing a tubular member.
2. Brief Description of Related Art
Wire line operations in a wellbore involve lowering a tool on a wire or cable, through a tubular member, into the wellbore. Similarly, coil tubing is often inserted through a riser and wellhead assembly into a wellbore. Under some circumstances, it is necessary to seal the tubular member without first withdrawing the cable or coil tubing. In these circumstances, a shear gate valve can be used to shear, or sever, the cable or coil tubing. Current designs of shear gate valves rely on a single longitudinal motion (primary motion of the gate) to provide a cutting action. There are problems associated with the sealing of gate valves after shearing coil tubing, wireline, or a combination of both, when the shearing is performed by longitudinal motion of the gate. Seemingly minor damage to the surfaces of the gate and seats can have an effect on the ability of the valve to seal.
Embodiments of the present invention can include a valve design featuring a profiled seat and a cylindrical gate design. The cylindrical gate operation can incorporate both a longitudinal and a rotational movement for valve actuation to shear of coil tubing, wireline, or a combination of both.
In various embodiments, a valve assembly can use a longitudinal and a rotational movement of a cylindrical gate in order to induce an alternative technique of shearing coil tubing, wireline, or a combination of both. The rotational movement can produce a second motion to the cutting interface of a shear valve during a cutting operation. The secondary motion can be at 90 degrees or at other angles relative to the primary motion of the gate. This can result in a cleaner cut of the coil tubing, wireline, or combination of both. Current designs of shear gate valves rely on a single longitudinal motion (primary motion) to provide the cutting action. The rotational movement provided by embodiments of the rotational shear valve can, in addition to adding a secondary motion to the cutting operation, tend to sweep any strands of wire or extruded material into the cavities of the valve rather than capturing this material and damaging the gate to seat interface. Embodiments can remove or reduce the likelihood of damage to sealing surfaces in gate valves.
Embodiments of the present invention can include a valve assembly that can have a valve body having an axial flow passage therethrough and a lateral bore transverse to the axial flow passage. Embodiments can also include a gate. The gate can have a cylinder rotated about a gate axis, the gate being located within the lateral bore and moveable in a longitudinal direction along the gate axis from an open position to a closed position. The gate can permit flow through the flow passage in the open position and a solid portion of the outer diameter of the gate can obstruct the flow passage in the closed position. The gate can rotate about the gate axis while moving axially from the open position to a closed position.
In embodiments of the valve assembly, the gate can include an orifice, the orifice being perpendicular to the gate axis and having opposite ends at the outer diameter of the gate, the orifice registering with the axial flow passage in the open position. In embodiments, the gate can include a slot on the outer diameter of the gate, the slot having a helical portion extending around the outer diameter as it extends in the direction of the gate axis, and the valve body can include a key, at least a portion of the key being located in the slot, so that when the gate moves along the gate axis, the key causes the gate to rotate about the gate axis. In embodiments, the slot can have a straight portion that extends along the gate axis and does not rotate helical fashion about the outer diameter and the key is located in the straight portion of the slot when the valve is in the open position so that when the gate moves from the open position to the closed position, the gate initially moves along the gate axis without rotating and then begins rotating when the key reaches the helical slot.
In embodiments of the valve assembly, the gate can include an orifice, the orifice being perpendicular to the gate axis and having opposite ends at the outer diameter of the gate. The orifice can register with the axial flow passage in the open position. The orifice can include a shear surface, the shear surface being the last portion of the orifice to register with the axial flow passage as the gate moves from the open position to the closed position. The transition from the straight portion of the slot to the curved portion of the slot can be a predetermined axial distance from the shear surface of the orifice so that the gate begins to rotate when the shear surface is the preselected distance crossing a circumference of the flow passage.
In embodiments of the valve assembly, a valve stem can be connected to an end of the gate and an actuator can be connected to the valve stem, the actuator creating force in the direction of the gate axis to urge the gate, via the valve stem, between the open and closed positions.
In embodiments of the valve assembly, the valve body can include a slot on an inner diameter of the lateral bore, the slot having a helical portion extending around the outer diameter as it extends in the direction of the gate axis, and the gate can include a key protruding from the gate, at least a portion of the key being located in the slot, so that when the gate moves along the gate axis, the key causes the gate to rotate about the gate axis. In embodiments of the valve assembly the valve body can include a cylindrical sleeve lining the lateral bore, the sleeve defining the inner diameter of the lateral bore and the slot being located on an inner diameter of the sleeve.
In embodiments of the valve assembly, the gate can include an end face, the end face having a shear surface, and the shear surface can rotate about the gate axis while the gate is moving from the open to closed position.
So that the manner in which the features, advantages and objects of the invention, as well as others which will become apparent, are attained and can be understood in more detail, more particular description of the invention briefly summarized above may be had by reference to the embodiment thereof which is illustrated in the appended drawings, which drawings form a part of this specification. It is to be noted, however, that the drawings illustrate only a preferred embodiment of the invention and is therefore not to be considered limiting of its scope as the invention may admit to other equally effective embodiments.
The present invention will now be described more fully hereinafter with reference to the accompanying drawings which illustrate embodiments of the invention. This invention may, however, be embodied in many different forms and should not be construed as limited to the illustrated embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art. Like numbers refer to like elements throughout, and the prime notation, if used, indicates similar elements in alternative embodiments.
Referring to
Valve body 102 is a valve housing having an axial flow passage 106. Axial flow passage 106 can be a cylindrical bore through which fluid can flow. Various drilling equipment including, for example, wireline run tools and coil tubing, can be passed through axial flow passage 106 when gate 104 is in an open position. Axial flow passage 106 can be oriented vertically when, for example, valve body 102 is connected to a riser or wellhead housing, or it can be oriented at an angle depending on its application. For purposes of this specification, a vertical orientation shall indicate that axial flow passage 106 is aligned with the wellbore or riser to which it is attached, unless otherwise indicated.
Valve body 102 can have connector 108 for connecting axial flow passage 106 to a tubular member (not shown). Connector 108 can include, for example, threaded bolt holes as shown in
Lateral bore 112 is a cylindrical bore through valve body 102. The axis of lateral bore 112 is generally perpendicular to the axis of axial flow passage 106. The inner diameter of lateral bore 112 is at least greater than the outer diameter of gate 104. The axial length of lateral bore 112 is greater than the axial length of gate 104 such that gate 104 can reciprocate within lateral bore 112. Valve body 102 can have a bore opening 114 at one or both ends of lateral bore 112. A valve bonnet 116 can be used to cover bore opening 114. As one of skill in the art will appreciate, bonnet 116 can be attached to, and sealingly engage, valve body 102 by any of a variety of techniques including, for example, studs 118 as shown in
Seat recess 120 is a counter bore within axial flow passage 106 that is proximate to lateral bore 112 for receiving and sealingly engaging seat 122. The inner diameter of seat recess 120 can be greater than the inner diameter of axial flow passage 106. One side of seat 122 is in a plane perpendicular to the axis of bore 106. The opposite side of seat 122 is saddle-shaped to sealingly engage the cylindrical side wall of gate 104 as gate 104 moves longitudinally and rotationally. Embodiments can have one seat recess 120, located above gate 104, or can have a pair of seat recesses 120 with one located above and one located below gate 104. Some embodiments can have no seats 122 and, thus, no seat recesses 120.
Gate 104 can be a cylinder rotated about a gate axis 124 as it is moved along gate axis 124. Gate 104 can be positioned within lateral bore 112, with gate axis 124 being parallel to the axis of lateral bore 112. Gate 104 can be moveable along gate axis 124, within lateral bore 112, from an open position to a closed position. Movement along gate axis 124 is defined as longitudinal movement. Gate 104 can permit flow through flow passage 106 in the open position, and a solid portion of the outer diameter gate 104 obstructs flow through flow passage 106 in the closed position. Seat 122 remains stationary while gate 104 is moved longitudinally and rotationally.
In some embodiments, gate 104 includes an orifice 126, which is an opening or passage through the outer diameter of gate body 128. Orifice 126 can be perpendicular to gate axis 124, such that orifice 126 is parallel to flow passage 106. When gate 104 is in the open position, orifice 126 can register with flow passage 106 to form a continuous path through valve assembly 100. When gate 104 is in the closed position, no part of orifice 126 is registered with flow passage 106, such that gate body 128 obstructs flow passage 106.
Orifice 126 can include a shear surface 130 (best shown in
The outer diameter of gate body 128 can have a slot 134. Slot 134 can be a groove that extends helically, axially, or both along the outer diameter of gate body 128. As best shown in
As best shown in
Referring back to
As one of skill in the art will appreciate, an actuator 166 (
Slot 178 can be located on an outer diameter surface of gate 168. A helical slot portion of slot 178 can engage a key (not shown in
Referring back to
In operation, valve assembly 100 can be connected to and in communication with a tubular member, such as a riser or a wellhead housing. Cable 132 (
As gate 104 moves in the longitudinal direction through lateral bore 112, key 142 rides in slot 134 to control the rotation of gate 104. As key 142 rides in the straight slot portion 138, gate 104 moves in the longitudinal direction without rotating about that axis 124. When key 142 engages helical slot portion 136, key 142 causes gate 104 to rotate about gate axis 124 as it continues to move in the longitudinal (along gate axis 124, and laterally relative to axial flow passage 106) in lateral bore 112. The movement along gate axis 124 causes orifice 126 to no longer be registered with axial flow passage 106, such that gate body 128 obstructs axial flow passage 106. The rotation caused by helical slot portion 136 engaging key 142 also causes orifice 126 to move out of axial alignment with axial flow passage 106. A member passing through axial flow passage 106, such as cable 132 or coil tubing (not shown), can be sheared by the longitudinal and the rotational movement of gate 104. Indeed, due to the longitudinal and rotational movement, the shear surface can be shifted away from the centerline of gate axis 124. In embodiments, cable 132 is trapped between shear edge 130 of gate 104 and a shear edge of seat 122, thereby causing the shearing. Cable 132 can be sheared before gate 104 is fully closed.
In some embodiments, the transition point 140 from straight slot portion 138 to helical slot portion 136 is a predetermined axial distance from shear surface 130 of the orifice 126 so that gate 104 begins to rotate when shear surface 130 is the preselected distance from a circumference of axial flow passage 106 or seat 122. In some embodiments, gate 104 begins to rotate just before cable 132 is pressed between shear surface 130 and an edge of saddle surface 164.
Referring to
Referring to
In embodiments having a sleeve 200, gate body 214 can have a smaller diameter than embodiments that do not have a sleeve 200 to accommodate the thickness of sleeve 200. By reducing the outer diameter of gate body 214 in embodiments having a sleeve 200, the dimensions of valve body 203, and bore 202, need not be changed. Seats 212 may need to be longer, however, so that they can engage the reduced-diameter of gate body 214. Thus, a sleeve 200 can be inserted into a standard valve body. Key 216 can be a dowel or stud protruding from gate 216. Key 216 can ride in slot 204, such that helical portion 206 causes gate 216 to rotate and straight portion 208 permits gate 216 to move laterally without rotating. In embodiments having a sleeve, the sleeve can be split into two or more segments to facilitate easier manufacture and assembly.
While the invention has been shown or described in only some of its forms, it should be apparent to those skilled in the art that it is not so limited, but is susceptible to various changes without departing from the scope of the invention.
