Drilling Fluids and Their Impact on Drilling Efficiency and Wellbore Integrity: An Applied Experience in Libyan Fields

• Mohamed Mansour Aljehani

  Petroleum Engineering Department, PetroLibya Academy for Higher Education and Training, Benghazi, Libya

  Author

• , Mustafa Ahmed Ben Hkoma

  Sustainable Development Research Center, Zletun, Libya

  Author

• Adnan Omran Akhleef

  Petro Libya Academy for Higher Education and Training, Benghazi, Libya

  Author

This paper examines the role of drilling fluids in improving drilling efficiency and preserving wellbore integrity under the geological and operational conditions of Libyan oil fields. It follows a descriptive-analytical approach that combines a structured review of recent peer-reviewed literature on rheology, wellbore stability, lost circulation, and emerging additives with an analytical reading of the author's twenty years of rig-site drilling fluids experience. The findings indicate that wellbore instability in shale formations results from coupled mechanical and chemical processes that a drilling fluid cannot resolve on its own; that fluid rheology changes with temperature and pressure, so surface measurements alone are insufficient; and that fluid selection is a trade-off between performance, cost, and environmental impact. The paper proposes a practical framework linking common drilling problems to specific fluid-related actions and recommends building geomechanical models for new wells, testing fluids under downhole conditions, documenting offset-well data, and running limited field trials before adopting new additives widely.

1. Mohamed Mansour Aljehani , Petroleum Engineering Department, PetroLibya Academy for Higher Education and Training, Benghazi, Libya

   Petroleum Engineering Department, PetroLibya Academy for Higher Education and Training, Benghazi, Libya

2. , Mustafa Ahmed Ben Hkoma, Sustainable Development Research Center, Zletun, Libya

   ^* Sustainable Development Research Center, Zletun, Libya

3. Adnan Omran Akhleef , Petro Libya Academy for Higher Education and Training, Benghazi, Libya

   Petro Libya Academy for Higher Education and Training, Benghazi, Libya

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