Accurate Downhole-Temperature Estimates are Critical to Proper SlurryDesign-Improved Data-Collection Method Field Tested Successfully

摘要

Temperature is a parameter of great importance when simulating and modeling cementing or temperature-activated fluids(McSpadden and Glover 2008) because it affects the amount of retarders or accelerators needed to avoid undesired phenomena,such as premature cement setting or incomplete consolidation of the treatments. In 1964, API introduced the first set of tables (API2005) that listed the circulating temperatures and hydrostatic pressures for certain wellbore circumstances and bottomholeconditions and the fluids that could be used in different well treatments, such as cementing, lost-circulation control, and water orgas control, etc. The API procedures have been widely adopted and recognized in the oil industry, and most operating companiesfeel comfortable using them. However, increased demand for oil and gas has forced operators to perform drilling, completion, andmaintenance operations in deeper and more complicated zones. These zones are often classified as high-pressure/high-temperature(HPHT) fields. Currently, combining computational tools, such as computer simulation software and measurement sensors, allows operators toaccurately measure temperature and pressure values and adjust them with well-known heat-transfer models; as a result, possibletemperature changes during complex operations can be more accurately modeled. This paper presents multiple case historiesshowing the significance of using bottomhole pressure/temperature (P/T) measurement tools and the modified modeling of theheat-transfer effects as a function of operational parameters (flow rate, density, wellbore geometry). With more accuratetemperature data, laboratory testing can be performed to better predict the behavior of the treatments mentioned when exposed tothe more complex bottomhole conditions encountered.