For E&P companies, the search for new, significant oil and gas finds means exploring in places where few companies have ventured before or in arenas that were only lately considered impractical. The remote locations and extreme depths to which these searches have brought operators have required them to construct wells in high-pressure and high-temperature (HPHT) conditions.
This reality is pressing service industry engineers tasked with the development of certain formation evaluation tools to find innovative solutions for HPHT downhole pressure measurement and sampling tools. The task is more problematic than other HPHT design challenges because, unlike many basic petrophysical measurement tools, pressure and sampling tools use significant power to run motors and pumps, which generate significant amounts of heat that is trapped inside the tool. Additionally, to acquire untainted reservoir fluid samples, these tools must often remain stationary downhole while fluids contaminated with mud filtrate are drained from the near wellbore. These conditions leave the tools exposed to punishing internal and external temperatures for extended periods of time. Similarly, during prolonged testing operations, downhole pressure gauge sensors must remain stable while maintaining measurement precision during exposure to high temperatures and pressures.
An article in the Autumn 2012 issue of Oilfield Review reviews two pressure and sampling tools that require high power to operate and were engineered to withstand HPHT conditions. Additionally, the article examines a recently introduced downhole pressure gauge that has been approved to operate for many hours at high temperatures.
Read the full article at the Oilfield Review Web site.
Avant C, Daungkaew S, Behera BK, Danpanich S, Laprabang W, De Santo I, Heath G, Osman K, Khan ZA, Russel J, Sims P, Slapal M and Tevis C: “Testing the Limits in Extreme Well Conditions,” Oilfield Review 24, no. 3 (Autumn 2012): 4–19.