Rotationally-actuated flapper valve and method

A rotationally actuated flapper valve including a flapper; a sinuous edge perimetrically about the flapper; and a congruous sinuous edge disposed at another component of the valve, the component being rotatable to misalign the congruous sinuous edge with the sinuous edge of the flapper whereby the flapper is urged out of a closed position and method.

BACKGROUND

Valves such as fluid loss control valves, safety valves, shut-off valves, etc. are very well known in downhole industries and especially so in the hydrocarbon recovery industry. Commonly, valves including but not limited to safety valves comprise a flapper and a flow tube operably configured to work together in a housing. The flapper can be driven off its seat by extension of the flow tube through the flapper. Although traditional safety valve configurations are ubiquitous and function well for their intended purpose, there is significant expense involved in manufacture due to material volume, machining work, etc. Reduction in costs while retaining function of flapper based valves will be welcomed by the art.

SUMMARY

A rotationally actuated flapper valve including a flapper having a non planar interaction surface thereon; a congruous component of the valve, the interaction surface and the congruous component being selectively alignable and misalignable and when misaligned the flapper is at least partially open.

A rotationally actuated flapper valve including a flapper; a sinuous edge perimetrically about the flapper; and a congruous sinuous edge disposed at another component of the valve, the component being rotatable to misalign the congruous sinuous edge with the sinuous edge of the flapper whereby the flapper is urged out of a closed position.

A method for actuating a flapper of a valve includes rotating one component of the valve relative to another component of the valve, the rotating causing misaligning if aligned or aligning if misaligned a nonplanar surface on one of the flapper or another component of the valve; and encouraging the flapper to another position pursuant to the rotating.

DETAILED DESCRIPTION

Referring toFIG. 1, an embodiment of the rotationally actuated flapper valve10is illustrated in a fully closed position with a flapper12engaged with a flapper seat14. Each of the flapper12and the seat14are embodied with a sinuous edge16and18, respectively. These edges are perimetrical about the flapper and seat and are generally congruous shapes, and in one embodiment are complementary shapes. When the flapper and seat are aligned, the flapper may be closed against the seat and in some embodiments will seal there against. Rotation of the seat or the flapper will cause the flapper and seat to move apart hence opening the flapper12to a degree. The degree to which the flapper opens is dependent in part of the angle of the slopes of the sinuous edges16and18. Angles approaching 45 degrees will permit the greatest flapper displacement and hence the greatest angular change relative to the seat14. Maximum movement of the flapper due to contact between edges16and18is achieved when a highest point of the sinuous edge16on flapper12is aligned with the highest point of the sinuous edge18on the seat14.

Misalignment of the flapper and the seat causes a lack of ability to seal and in fact can be used to cause the flapper to open, as is the intent in this embodiment. The high points of the sinuous edges16and18interfere with one another to cause a pivoting movement of the flapper12about a pivot20(seeFIG. 4).

In the embodiment illustrated inFIGS. 1-4, the valve10is depicted in the closed, partially open and open positions to provide a clear understanding of the valve10. In this embodiment the configuration relies upon the sinuous edge detail16and18, a helical groove22and a groove follower24, and a helical spur gear26driven by a suitable drive28.

Operation is best described sequentially referring toFIGS. 1-3. InFIG. 1, the flapper12is closed and the seat14is at a position relative to the housing and the flapper that allows the flapper to engage in a sealing relationship with the seat14. Upon actuation of a drive28, which may be an electric motor (illustrated with electrical connections30and32inFIG. 1), hydraulic motor (illustrated with hydraulic fluid inlet34and outlet36inFIG. 2), etc. that is in driving communication with the spur gear26, the seat14rotates about its own axis thereby misaligning the sinuous edge18of the seat14with the sinuous edge16of the flapper12. This causes the flapper12to be urged in an axial direction away from the seat14. Because the flapper12is hingedly connected to a housing38within which the seat14rotates, the flapper will pivot about pivot20pursuant to the axial load thereon. The degree of pivot of the flapper12is, as noted above, related to the angle of the sinuous edges but it is often less than fully open due to limitations of possible slopes. Limitations may be related to geometry alone or may be related to frictional increases, as the slope gets steeper. In order to efficiently achieve a fully open condition as illustrated inFIG. 3, the seat14moves axially at the same time that it moves rotationally. This occurs pursuant to the follower24riding in helical groove22as the drive28forces the seat14to rotate. The spur gear26is helically configured in order to stay engaged with the drive28as the seat14changes position axially. Because the seat14moves in the direction of the flapper, the contact point40between the seat14and the flapper12continues to urge the flapper12until it is fully open as shown inFIG. 3.

The flapper is closed in this embodiment by a return spring42, visible inFIG. 4.

Referring now toFIGS. 5 and 6, an alternate embodiment that rotationally actuates two opposed flapper valves simultaneously is illustrated. It will be apparent to one having read the foregoing that this embodiment includes a mirror image of the components in the first discussed embodiment. A single drive28actuates both of the mirrored configurations and they operate identically to each other but in opposite directions. For clarity each of the components in the mirrored section are endowed with a 100 series equivalent of the numerals used in the first described embodiment.

Referring toFIGS. 7-9, yet another embodiment of a rotationally actuated flapper valve is illustrated. InFIG. 7, a perspective view with the valve open provides an overview of the configuration. The valve210includes a flapper212and a flapper seat214. The flapper seat in this embodiment is distinct from those in the previously described embodiments in that it employs a ramp sleeve250, which is rotatable to cause full open movement of the flapper212. The flapper is still initially motivated by rotational movement of the seat214but in order to move the flapper to the fully open position, the sleeve is added. The sleeve250is also the motivator for the seat214as it is connected to the seat214through fingers251. Sleeve250includes, in one embodiment, a ring gear (or at least a partial ring gear)252extending annularly about the sleeve250. The ring gear252is employed to cause rotation of the sleeve250and thereby open or close the flapper212. Any suitable drive may be employed to actuate the ring such as the drive28illustrated in the foregoing embodiments. In the sleeve250is formed an angular groove or opening254. As illustrated, the configuration is an opening that extends completely through the sleeve250but it can also be configured to be a recess into the sleeve from the inside dimension surface of the sleeve250, if desired. In any event, the groove254is of complex shape in one embodiment wherein the groove254both is helically configured relative to the sleeve axial direction and is also angled relative to that axial direction as illustrated inFIG. 9. Numerals256and258designate particular walls of the groove254. InFIG. 9, the observer can see the angle of the walls. The angles seen inFIG. 9are relatively steep while the angle of the same walls in an area of the walls that can be seen inFIG. 8is substantially less steep. This is so because the walls are configured to provide a surface upon which a cam, which may be a cam roller260as illustrated, can bear with a load normal to the wall during movement of the flapper212. Referring toFIG. 8, the cam roller's position relative to the flapper212is apparent. The cam roller260is supported by an extension262of the flapper212located opposite the location of the body of the flapper relative to the pivot220. Therefore, a movement of the extension262in one direction will cause movement of the flapper212in an opposite direction. By urging the cam roller260to either end of the groove254from the central region of the groove causes the roller to climb the angled groove and urge the flapper212into an open position. During the movement of flapper212about pivot220(seeFIGS. 8 and 9sequentially) the cam roller260is moved to a significantly different orientation. The groove254is configured to match the motion of the cam roller by keeping the walls256and258normal to the roller260in order to improve efficiency of mechanical movement. Reversal of movement of the sleeve250will close the flapper212by urging the cam roller260back to a central location264of the groove254.

Referring now toFIGS. 10 and 11, another alternate embodiment of the rotationally actuated flapper valve310is illustrated. In this embodiment, a flapper314is similar to those in the foregoing embodiments in that a sinuous edge316is included. Edge316mates and in some embodiments seals with a congruous (or in one embodiment complementary) edge318, that is configured at an end of a flow tube370, when the flapper is aligned and closed. The flow tube370is rotationally and axially moveable within a housing372and is biased to a valve closed position by a biasing member374such as a coil spring as illustrated. The flow tube370includes a biasing member attachment feature376such as a flange as shown. The tube370is constrained to rotational movement for a number of degrees of rotation when the valve is in the closed position by a groove378in a constraint sleeve380. It is to be appreciated that the groove378is configured to extend laterally along the constraint sleeve380for a number of degrees and then to extend axially of the sleeve380. This ensures that the flow tube370must rotate first and then extend longitudinally pursuant to rotational actuation explained further hereunder. The movement of the flow tube370first begins to open the flapper312due to misalignment of the sinuous edges316and318as is the case in the foregoing embodiments and then the flapper is openable fully by the extension of the flow tube through the seat314with inherent protection of the flapper behind the flow tube in the fully open position. Extension of the flow tube370only occurs when the constraint sleeve380allows that movement. This requires that a lug on the flow tube382that is engaged with the groove378has moved rotationally far enough for the lug to have moved into the axial portion of the groove378.

Initiating the movement just described is a drive328, which may be an electric motor, hydraulic motor, etc. as in the foregoing embodiments engaged with a gear352. Careful reference toFIGS. 10 and 11will reveal that the flow tube370is in close concentric communication with a drive tube384. The flow tube370includes a helical profile386and the drive tube384includes a helical profile388. The profiles386and388are congruous and in one embodiment complementary to one another and in any event are configured so that the rotational movement of the drive tube384will transfer rotational motion to the flow tube370and when permitted by the constraint sleeve380will cause axial motion. The axial motion is due to a climbing of each profile relative to the other similar to a large pitch captured nut jack screw arrangement.

In operation, and beginning from a closed flapper position, the drive328is actuated to impart rotational motion to the drive tube384. Because the flow tube is constrained in axial movement due to constraint sleeve groove378, the movement of the flow tube is solely rotational. The rotational movement misaligns the sinuous edges316and318causing the flapper312to partially open. When the rotational movement just described succeeds in moving the lug382to the axially oriented portion of the groove378, further rotational movement of the flow tube is prevented by the constraint sleeve380. At this point in actuation of the valve310, the rotational movement of drive tube384is translated to axial movement of the flow tube370by the action of the profiles386and388. The flow tube370is then axially extended through the flapper314a sufficient distance to fully open and protect the flapper312. This position is illustrated inFIG. 11where the flapper314in a completely open position is illustrated behind the flow tube370and the spring374is illustrated compressed. Further, an axial distance between flange376and gear352can be seen to have increased fromFIG. 10toFIG. 11. Depending upon the degree to which opening of the flapper is desired; the axial extension portion of this embodiment may or may not be employed. It is possible to simply employ the rotational portion by rotating the flow tube directly with a drive.