Drill stem test

A Drill Stem Test (DST) is a temporary completion of an oil or gas well to determine reservoir parameters such as: pressure, fluid type, permeability, etc. In conjunction with other data it can answer fairly early and economically whether a drilled well is viable to produce.

It is normally run after a well has been drilled and logged with the drilling rig still on location. Based on the results from a DST the well could be cased and put into production or abandoned.

In recent years Horizontal Well Testing is the newest area for oil companies to focus on. This presents a challenge for most of the old DST test strings in that they rely on rotation or up and down movement to inflate their packers or open and close down hole valves. This operation becomes very difficult once you try to get feedback at surface from around the bend (heel) of a Horizontal Well.

The best systems do not rotate or move the drill string up or down. They are totally electronic and use computer commands from surface to do all these functions and power up the down hole tools and gather data.