John Hall, Senior Production Technologist , Expro Group, Aberdeen, UK
A UK gas storage company needed to identify which wells were underperforming in order to maximise performance. The data acquisition operation was required to:
• integrate well with platform processes
• be carried out on all available wells in one campaign
• have no impact on gas nominations.
DRC were able to provide a low cost solution with the SPIDR. Production personnel had no problem in programming and downloading data. Rig up was simple and the SPIDR was sufficiently robust to use on all available wells in one campaign.
Data was captured with minimal impact on platform operations and no impact on gas nominations. The converted pressure data provided by DRC was reliable and has helped the client identify a number of underperforming wells. DRC were quick and effective in their response to queries and their knowledge was invaluable in solving one or two unusual pressure responses.
I would be more than happy to use DRC for future pressure data acquisition operations.
In my business I spend a lot of time analyzing pressure data from fracture injection tests using NuTechís NuFIT process. The results of this analysis provide a measure of the permeability and pore pressure that is needed to understand if the reservoir will be commercial after completion. However in some cases the data can be difficult to analyze because of a high level of noise in the recording instrument, unexplained spikes in the data and periods with no data recorded. Other memory gauges can require extensive editing to correct these data problems, introducing uncertainty into the analysis. The DRC SPIDR gauge however consistently provides high quality data free of uncertainty. When asked what gauge I would use, I recommend the SPIDR gauge from DRC.
Corby Goodman, Senior Completion Engineer, NuTech Energy Alliance, Humble, TX
We have successfully used the SPIDR surface pressure data instrument for well testing since 1995 on both gas-condensate wells and gas storage wells. SPIDR provides valuable information at a very low cost. We have run them in conjunction with down hole gauges while running an extended well tests on single wells as well as multiple systems. The ease of hooking them to a well head and the non-intrusiveness of the equipment make it very practical.
We have relied on the DRC engineers for information, converting the pressure transient data, and analyzing the results.
Jim Junkins, Manager of Operations, eCORP Development, LLC, Houston, TX
I have been pleased to be associated with Dr. Nathan Waldman before there was a concept of a SPIDR. DRC has been developing technology for surface to downhole pressure measurement for the past 29 years in parallel with my own efforts to develop a capillary wave based transient model. During those years the proof of concept has been to produce blind maps that compare well and in detail with seismic imaging. In order to perform this task the first step resides in data gathering. Stability of the instrumentation is critical to the task but the key is acquiring accurate surface to bottomhole pressure conversions. This is not as simple as the textbooks make it out to be. The key is relative pressure measurement with appropriate conversions for thermal decay.
In the early 1980ís it was my responsibility to sponsor an R&D effort in the National Laboratory System to produce such a surface pressure to downhole pressure algorithm. The US Dept of Energy spent half a million dollars and failed to produce credible downhole conversions when provided both surface and downhole pressure data. DRC succeeded and has produced over half of the data sets that WAVEX has used for ìBlind Pressure Mapping.î
DRC and WAVEX began working together back in 1997 on a collaborative basis and have been delivering cost effective quality energy mapping since. Surface data works and works well on virtually all gas wells. It is the minority of cases that require downhole services. What is the point of risking a well with wire when wireless testing works on the vast majority of gas wells? We have had successes on oil wells as well when testing conditions were too severe to consider a downhole gauge.
I am proud of my long association and moreover the stunning results that both companies have achieved.
Dr. Fred L. Goldsberry, P.E., Ph.D, MBA, President, Wavex, Inc., Houston, TX
DRC and the SPIDR well testing system have been a great tool in the evaluation process of the wells I look over. They have been very dependable and accessible for the many years that I have been using them. I have been using the SPIDR system for both the typical application of pressure transient testing (build-ups/drawdowns) as well as well pressure monitoring. During my time as production engineer looking over a very high-profile field, I had the SPIDR system monitoring the well head pressure for the entirety of the intervention. The well was a high pressure, high temperature Gulf of Mexico gas-condensate reservoir and I was reluctant to run any downhole gauges. This allowed me to have high quality wellhead pressure data that would be converted to bottomhole conditions but also acted as a backup all other data being collected. This gave me an opportunity to collect values for permeability, skin and P* while the well was shut-in without added intervention. I trust in both the accuracy and reliability of the SPIDR well testing system for all my surface pressure acquisition needs.
Timothy H. Bertsch, Artificial Lift Engineering Tech, Shell E&P, New Orleans, LA
The SPIDR device is attractive to us at EOR for many reasons. For our St. Johnís CO2/Helium ...