Patent ID: 6571875
Filing Date: 2003-06-03
Classification: C09K,E21B

Abstract:
An apparatus comprising:a cylindrical housing having an exterior and a longitudinal bore extending therethrough; a lateral port communicating between the housing longitudinal bore and the exterior of the housing; a first sleeve disposed within the housing longitudinal bore and having a cylindrical wall and a longitudinal passageway therethrough, capable of being positioned in an upper position and a lower position relative to the housing; first and second lateral passageways extending through the wall of the first sleeve; a second sleeve disposed within the first sleeve and having a longitudinal passageway therethrough and capable of being positioned in an upper position and a lower position relative to the first sleeve; a first flow passage extending longitudinally through the housing; and a second flow passage extending longitudinally through the housing; wherein when the first sleeve is in the upper position, and the second sleeve is in the lower position, communication is established between the longitudinal bore of the housing above the second sleeve and the exterior of the housing, and communication is established between the longitudinal bore of the housing below the second sleeve and the first flow passage; wherein when the first sleeve is in the lower position, communication is established between the longitudinal bore of the housing above the first sleeve and the second flow passage.