Flow control devices for flow conductors

Claim 1

A FLOW CONTROL DEVICE, FOR A WELL FLOW CONDUCTOR HAVING A LONGITUDINAL FLOW PASSAGE AND A FIRST LATERAL PORT COMMUNICATING WITH THE FLOW PASSAGE INTERMEDIATE THE ENDS THEREOF, INCLUDING: AN ELONGATE MANDREL POSITIONED IN THE WELL FLOW CONDUCTOR AND PROVIDED WITH AN INTERNAL FLOW PASSAGE FOR COMMUNICATING AT ITS UPPER END WITH THE FLOW PASSAGE IN THE WELL FLOW CONDUCTOR AND WITH A SECOND LATERAL PORT INTERMEDIATE THE ENDS OF THE MANDREL FOR COMMUNICATING WITH THE EXTERIOR OF THE MANDREL AND SAID INTERNAL FLOW PASSAGE AND WITH SAID FIRST LATERAL PORT; SEAL MEANS CARRIED BY THE MANDREL FOR SEALING BETWEEN THE WELL FLOW CONDUCTOR AND THE MANDREL BELOW SAID LATERAL PORTS, SAID MANDREL HAVING AN APERTURE FOR COMMUNICATING WITH THE FLOW PASSAGE OF THE WELL FLOW CONDUCTOR BELOW THE SEAL MEANS; MEANS CARRIED EXTERNALLY BY THE MANDREL PERMITTING FLOW IN ONE DIRECTION ONLY INTO THE INTERNAL FLOW PASSAGE OF THE MANDREL THROUGH SAID SECOND LATERAL PORT AND SAID APERTURE; AND SEAL MEANS ON SAID MANDREL FOR SEALING BETWEEN THE MANDREL AND THE WELL FLOW CONDUCTOR ABOVE SAID PORTS.