Patent ID: 8439118
Filing Date: 2013-05-14
Classification: E21B,Y10T

Abstract:
1. A valve for subterranean use in a tubular string, comprising: a housing with end connections adapted for mounting the housing to the string; a flapper pivotally mounted in a recess adjacent a passage in said housing, said passage extending between said ends, said flapper mounted on a pivot and biased to move toward a seat that surrounds said passage when said flapper is not selectively retained in said recess by a flow tube, said flapper defining the closed position by contacting said seat; said recess defined by an enlarged dimension for said passage in said housing and said flapper selectively disposed within said recess when said flapper is retained by said flow tube, said recess extending circumferentially beyond said flapper and an insert mounted at least in part in said recess said insert acting to at least reduce a flow induced vortex in said passage adjacent said flapper created by flow that would otherwise move said flapper toward said seat, said vortex, without said insert, otherwise raising pressure adjacent the flapper to a level that retains said flapper in said recess by overcoming said bias to said closed position when said flapper is not selectively retained in said open position by said flow tube.