Abstract: A downhole shut-in tool includes in one aspect a pilot valve which when opened places a differential pressure across a piston which in turn operably engages a shut-in valve element to close the shut-in tool. An electronic timer assembly and electric drive motor are provided for controlling the action of the pilot valve. The drive motor is controlled by a load sensor which senses that the motor has stalled when an actuator engages a movement limiting abutment. In another aspect a pilot valve is provided which can selectively communicate the pressure differential across the piston so as to repeatedly open and close the shut-in valve element. Efficient methods of drawdown and buildup testing using such an automated multiple operating shut-in tool are provided. Associated automated sampling tools are also disclosed.
Type:
Grant
Filed:
May 27, 1993
Date of Patent:
January 18, 1994
Assignee:
Halliburton Company
Inventors:
Roger L. Schultz, Craig L. Zitterich, Harold K. Beck, William L. Bohan