公开(公告)号：US1801513A

公开(公告)日：1931-04-21

申请号：US29112828

申请日：1928-07-07

Applicant: KOPLIN HARRY

Inventor： BERNHARD LINDBERG

IPC: D06F1/08

CPC classification number: D06F1/08

公开(公告)号：US3924677A

公开(公告)日：1975-12-09

申请号：US50162274

申请日：1974-08-29

Applicant: KOPLIN HARRY

Inventor： PRENNER AMNON ,  BEAR JACOB ,  TOHAR DAVID ,  KOPLIN HARRY

IPC: E21B43/11 ,  E21B33/12

CPC classification number: E21B43/11

Abstract: Apparatus for providing a passage between an earth stratum and the interior of a well casing comprising a movable hollow conduit member mounted in the casing wall initially held retracted and immovable, while the casing is lowered, and subsequently, after the casing is set, extended outwardly from the casing wall to contact the stratum. A water soluable plug initially blocks the bore of the conduit member, and the apparatus includes removable means on each end of the plug for preventing premature contact of water with the plug.