Detecting Gas-In-Pipe (GIP) During A Drill Stem Test (DST).

Detecting natural gas in the drill pipe during a drill stem test is often a straightforward process.  The natural gas is typically visible during the trip out of the hole with the test tool. The removal of the stand containing natural gas from the drill string causes a difference in the light refraction  (bending of light) around the pipe, hence indicating the presence of natural gas.  The raw natural gas recovered during the drill stem testing process can also be noticed by the odor it emits which is unique and identifiable.  However, utilizing this method of “sniffing” natural gas poses a serious health risk due to the H2S content that maybe present in the gas, therefore this method should not be used.  

So what are the options for detecting natural gas when ‘straightforward’ isn’t so clear-cut?  During a drill stem test many environmental variables can cause an inability to see the light refraction caused by the natural gas.  Strong winds or a lack of adequate light to observe this phenomenon can cause natural gas in the pipe to be missed.  In these cases gas-in-pipe (GIP) can become extremely hard to pinpoint.  That is why Diamond Testing utilizes a methane detection wand to measure the existence of natural gas in the drill string.  The wand provides the tester the ability to determine if natural gas is present from within the pipe, therefore, eliminating the variable of wind and/or inadequate lighting.  This method of detection provides not only a safe way to pinpoint natural gas, but allows for an accurate method for detecting natural gas concentration in the drill string.  By utilizing this tool, Diamond Testing provides the operator with a clear and precise understanding of his recovery during the drill stem test.

While the measurement of gas-in-pipe in the recovery has been a part of drill stem testing data collection over the years, the accuracy of that data often times had errors caused by the environmental variables discussed above.  Following our mission to provide ever-improving value to our customers, Diamond Testing has added this new tool and accompanying gas detection procedures to all drill stem tests in an effort to remove these errors and enhance overall data collection and retention.  Utilizing the gas detection wand and feeding this more accurate information directly to our customers through the PORTAL system, the operator can feel confident that he/she has received the most accurate information available for their wellsite.