Successful Experience of Water-Base Drilling Fluid Products Working in Synergy to Optimize Drilling Operations for Horizontal Wells in Extra-Heavy Oil Reservoir

Telles, J. (Schlumberger) | Rojas, L. (Schlumberger) | Díaz, L. (Schlumberger) | Atencio, N. (Schlumberger) | Cortés, A. (Schlumberger) | Calderón, E. (Schlumberger) | Dorca, J. (Schlumberger) | Peñaranda, J. (Schlumberger) | Navarro, V. (Schlumberger) | Ydrogo, C. (PDVSA) | Mata, L. (PDVSA) | Correa, E. (PDVSA) | Páez, D. (PDVSA)


Accretion is a common phenomenon that affects drilling operations in the Orinoco Heavy Oil Belt. The main reservoir, where most horizontal sections are drilled, is the Oficina Formation. Accretion negatively impairs operational efficiency, thus generating stuck pipe incidents, problems while tripping due to high torque and drag values related to friction factors, and the unrecommended backreaming operations. In addition, accretion causes excessive fluid surface losses linked to plugged shakers screens. This document shows the laboratory tests and successful field results obtained from the combination of specialized surfactant and lubricant agents working in synergy to reduce the accretion effect. The laboratory test demonstrated the synergy between the lubricant and surfactant in different tests, such as lubricity, accretion, and permeability damage testing. In the field, positive results were achieved in nine horizontal wells, thus increasing operative efficiency by reducing stuck pipe incidents, backreaming operations, and unplanned trips. This impact over flat times was also accompanied by a fluid waste reduction that improved the shakers' screen usage and reduced the amount of oil coating the cuttings, which facilitated the treatment process and minimized environmental impact.