Open Hole: Bottom Hole Compression
Bottom Hole Compression or Conventional drill stem tests use compression-set packers set above the formation, with tail pipe (drill collars or hevi-wate drill pipe) below the packers to the bottom of the hole. Placing weight on the tool string compresses the packers creating a seal before hydraulic valve opens, allowing the formation to flow.
The formation is flowed for a specified time period, after which the drill pipe is rotated five turns to the right to close the shut-in tool for a specified shut-in period (build-up). Five more right-hand rotations opens the shut-in tool for a second flow. Five more rotations (total 15) closes the shut-in tool for a final build-up. The tubing/drill pipe contents can be reversed out of the string though the pump-out-sub before pulling up on the drill pipe to close the Downhole Sampler and release the compression packers.
Find information on any of our DST services.
Solutions recently used in geothermal