Cased hole drill stem tests (DST) are conducted after the well has been cased and the formation of interest is behind casing. The casing is perforated by wireline perforating guns or with tubing conveyed perforating (TCP) guns connected to the bottom of the DST string to open the casing to the formation. The DST tool assembly is run at the bottom of the temporary production tubing or drill pipe (work string) and used for downhole well testing (inflow testing) and stimulation (injection).

Open Hole: Inflate Straddle

Open hole inflate tests utilize a pair of interval spaced packers which are inflated using annular fluid to isolate the formation of interest. This type of testing is adaptable to a wide range of conditions. Inflate testing is the most time and cost-effective method used to isolate multiple formations during a single run in the hole.

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.

Inflatable Packer System

The Inflatable Packer System isolates an open hole interval. It can be configured with one (Bottom Hole) or two packers (Straddle). The Inflate Straddle configuration is capable of multiple resets allowing independent testing or treatment of multiple intervals with one trip in the hole.

Custom Solution

Northstar supports over one hundred downhole tools. Our team of in-house professional engineers are continually designing new downhole equipment and our Downhole Specialists are continually creating new tool combinations (solutions) for different industry applications. Northstar also has an HPHT Deep Well Simulator capable of re-creating virtually and downhole scenario to validate the design prior to running in a live well.