ANCHOR PACKER Russian patent published in 1997 - IPC

FIELD: drilling of oil and gas wells, in particular, in their testing in process of drilling by tubular formation tester. SUBSTANCE: sealing member of lower packer is made of rubber. It is made for tight adjoining to well walls in its nominal diameter. The anchor packer has upper and lower check valves for bypassing drilling mud. Stud holds upper check valve constantly opened. Lower check valve is kept in operating position by stud. Lower check valve allows the drilling mud to flow only upward. Stud is sheared when device is lifted above 2 m. This provides for switching over of valves and proper operation of sealing rubber member in pressure differential from bottom upward in its seating. EFFECT: provision of device functioning as lower packer and anchor. 4 cl