Patent Grant
9976387
The field of the invention is a two way check valve and more particularly where there are features to convert the operation to one way operation after actuating a subterranean tool so that other operations can then take place.
Check valves are used in a variety of applications to limit flow in one direction while allowing flow in an opposite direction. Typically two way check valves are used to prevent flow in opposed directions when actuated but having been actuated they remain closed to flow in both directions. Some examples of these types of valves are: US2012/0222861 and U.S. Pat. No. 4,628,996 (FIGS. 11 and 12). Other designs just cut off flow in multiple directions when there is a line break such as U.S. Pat. No. 5,547,029. Some designs use redundant check valves in parallel that interact such as U.S. Pat. No. 6,659,184 FIG. 2. Yet other designs are mainly one way check valves but mention in passing that they could be configured as two way check valves without describing how that would be usefully accomplished in the context of their disclosure such as US2013/0255952. Yet other designs are multidirectional valves that redirect flow in various flow regimes and are not necessarily check valves at all such as U.S. Pat. No. 7,658,229.
In some applications there is a need to build pressure in a downhole direction such as for setting a packer and then having set the packer to convert to a unidirectional check valve operation where flow is permitted in the downhole direction but prevented in the uphole direction. In a specific application, a heavy oil that needs to be diluted so that it can be pumped to the surface with an electric submersible pump (ESP) requires the ability to pump down the diluent in a downhole direction while providing a safety device that will prevent flow backing up the diluent delivery line should the formation experience a pressure buildup. At the same time a packer needs to be set to isolate the heavy oil from the remainder of the borehole so that mixing with the diluent can happen below the packer. The present invention address this specific situation and is suitable for other applications where for a time single direction checking of flow is desired such as to set a packer and at other times flow is enabled in a direction previously checked to accomplish another downhole objective such as fluid dilution of a heavy oil so it can be pumped to the surface with an ESP. These and other aspects of the present invention will be more readily apparent to those skilled in the art from a review of the description of the preferred embodiment and the associated drawings while recognizing that the full scope of the invention is to be determined by the appended claims.
A selectively two directional check valve is located on a string with a packer and is either held open for running in so that the string can fill and doesn't become buoyant or includes a closable ported sub to allow string filling for running in that can then be closed. Pressure is applied from the surface to drive an object down to a seat so that a packer can be set. Further pressure increase shifts the object and the seat and locks the seat in the shifted position. A spring return force pushes the object to an upper seat to prevent uphole flow. Flow in the downhole direction is possible by overcoming the spring bias to move the object off the upper seat while preventing the object from moving down far enough to engage the shifted lower seat. Flow downhole just goes around the object.
In the intended application the device first allows string 12 to fill as it is positioned at the desired location for setting the packer 13. The packer 13 is allowed to set because pressure from the surface is contained and directed to the packer 13 until it sets. After setting the packer 13 further pressure increase breaks shear restraint 20 and locks the lower seat in a shifted position that precludes the object 24 from landing on the seat 18. This allows fluid to be delivered through the string 12 past the packer 13 to mix with the heavy oil that then is pumped with the ESP or other type of pump P through the packer 13 in a parallel passage represented by arrow 14 so that the blended flow reaches an outer annulus around the string 12 in the zone above the packer 13. In the unlikely event of a pressure surge in the reservoir, flow toward the string 12 is blocked as the object 24 with the aid of the spring 30 is pushed to the point of seating off on seat 36 to block flow in the uphole direction.
While spring 30 is shown as a coiled spring other types of springs like a Belleville washer stack or compressible gas can also be used. The permitted flow directions can also be changed in the invention while retaining the feature of selective checking flow in at least one direction for one operation while later allowing such a flow for accomplishing discrete purposes.
The above description is illustrative of the preferred embodiment and many modifications may be made by those skilled in the art without departing from the invention whose scope is to be determined from the literal and equivalent scope of the claims below:
| Number | Name | Date | Kind |
|---|---|---|---|
| 3001585 | Shiplet | Sep 1961 | A |
| 4628996 | Arnold | Dec 1986 | A |
| 5320181 | Lantier, Sr. | Jun 1994 | A |
| 5547029 | Rubbo et al. | Aug 1996 | A |
| 6659184 | Tips et al. | Dec 2003 | B1 |
| 7509969 | Huang | Mar 2009 | B2 |
| 7658229 | Becker et al. | Feb 2010 | B2 |
| 8037940 | Patel | Oct 2011 | B2 |
| 20120222861 | Eriksen | Sep 2012 | A1 |
| 20130153239 | McIntosh | Jun 2013 | A1 |
| 20130255952 | Hailey, Jr. et al. | Oct 2013 | A1 |
| Number | Date | Country | |
|---|---|---|---|
| 20150308225 A1 | Oct 2015 | US |
