Patent ID: 7520336
Filing Date: 2009-04-21
Classification: E21B

Abstract:
1. An apparatus for diverting fluid flow out of a work string, the apparatus comprising: a housing having an internal bore, an upper end, and a lower end, wherein the housing has at least one exterior port; a circulating sleeve positioned within the internal bore of the housing, the circulating sleeve having at least one exterior port, wherein the circulating sleeve is adapted to sealingly slide within the internal bore of the housing from an Initial position to at least a second position, wherein in the second position the at least one exterior port of the circulating sleeve is aligned with the at least one exterior port of the housing; a spring, the spring positioned to bias the circulating sleeve to its initial position; a locating sleeve positioned on the circulating sleeve, the locating sleeve having a continuous j-track, wherein the locating sleeve rotates round the circulating sleeve and moves with the circulating sleeve along the internal bore of the housing compressing the spring; a lower pin having an interior end and exterior end, the exterior end being connected to the housing and the interior end positioned within the j-track; and a seat connected to the circulating sleeve, the seat being adapted to catch a dart and block the internal bore of the housing, wherein fluid pressure above the dart moves the circulating sleeve from the initial position to the second position within the internal bore, the dart being adapted to deform under a predetermined pressure allowing the dart to pass through the seat, thereby enabling fluid flow through the internal bore of the housing.