Prediction of Hydrostatic Pressure and Downhole Mud Temperatures While Drilling


  • L. V. Eppelbaum Dept of Earth Sciences, Raymond and Beverly Sacklers Faculty of Exact Sciences, Tel Aviv University, Ramat Aviv 69978, Tel Aviv, Israel
  • I. M. Kutasov BYG Consulting Co, Boston, USA


Drilling fluids, deep wells, bottom hole temperature, hydrostatic pressure, circulating temperature


In deep and hot wells, the densities of water/oil muds and brines (geofluids) can be significantly different fromthose measured at surface conditions. As a result, bottom-hole pressures predicted with constant mud densities can bein error by hundreds of psig. Determining accurate the density of drilling mud (the density of the formation fluids) underdownhole conditions needs for calculating the actual hydrostatic pressure in a well and predicting differential pressure atthe bottom-hole. This will help to reduce the fluid losses resulting from miscalculated pressure differentials. In areas withhigh geothermal gradients, the thermal expansion of drilling muds can lead to unintentional underbalance, and a kickmay occur. In this paper we demonstrate the use of an empirical equation for the downhole circulating mud temperatureas well as the early derived analytical equation for the drilling mud hydrostatic pressure. A field example is presented.






How to Cite

L. V. Eppelbaum, I. M. Kutasov. Prediction of Hydrostatic Pressure and Downhole Mud Temperatures While Drilling. Int. J. Petrol. Technol. [Internet]. 2016Mar.1 [cited 2021Sep.16];2(2):53-7. Available from: