Drilling Fluids and Cementing – MCQs 50 Score: 0 Attempted: 0/50 Subscribe 1. The primary function of drilling fluid is to: (A) Cool and lubricate the bit (B) Carry cuttings to the surface (C) Control formation pressures (D) All of the above 2. Which of the following is NOT a type of drilling fluid? (A) Water-based mud (B) Oil-based mud (C) Synthetic-based mud (D) Gasoline-based mud 3. The hydrostatic pressure of drilling fluid depends on: (A) Mud density and depth (B) Drill pipe diameter (C) Bit size (D) Rate of penetration 4. Which property of drilling mud is measured using a Marsh funnel? (A) Gel strength (B) Viscosity (C) Density (D) Filtration loss 5. Barite is commonly added to drilling mud to: (A) Reduce viscosity (B) Increase density (C) Control pH (D) Prevent corrosion 6. Mud cake forms on the wellbore wall due to: (A) Fluid loss to formation (B) Excess gas in mud (C) Bit wear (D) Cement slurry invasion 7. The pH of water-based drilling mud is usually maintained between: (A) 3 – 5 (B) 6 – 8 (C) 8 – 10 (D) 12 – 14 8. Oil-based mud is preferred in which condition? (A) High-temperature wells (B) Reactive shale formations (C) Offshore drilling (D) All of the above 9. Which instrument measures drilling mud density? (A) Viscometer (B) Mud balance (C) Marsh funnel (D) Hydrometer 10. The rheological model most commonly used for drilling fluids is: (A) Newtonian model (B) Bingham plastic model (C) Ideal gas law (D) Exponential model 11. Drilling fluid contamination by salt usually leads to: (A) Reduced mud weight (B) Increased viscosity (C) Decreased gel strength (D) Improved lubrication 12. Which gas is most dangerous if entrained in drilling fluid? (A) Oxygen (B) Hydrogen sulfide (H₂S) (C) Carbon dioxide (D) Nitrogen 13. Which drilling problem occurs due to insufficient mud density? (A) Lost circulation (B) Wellbore collapse (C) Kick or blowout (D) Mud cake thickening 14. A common additive to reduce fluid loss in mud is: (A) Starch (B) Lime (C) Barite (D) Hematite 15. Gel strength of drilling mud is important for: (A) Hole cleaning during circulation (B) Suspension of cuttings when circulation stops (C) Bit lubrication (D) Reducing corrosion 16. Which drilling fluid is best suited for environmentally sensitive areas? (A) Oil-based mud (B) Water-based mud (C) Diesel-based mud (D) None of the above 17. Excessive solids in drilling mud may cause: (A) High viscosity and poor hole cleaning (B) Reduced density (C) Decreased filtration control (D) Improved lubrication 18. The main objective of cementing in drilling is to: (A) Provide zonal isolation (B) Support casing (C) Protect casing from corrosion (D) All of the above 19. Primary cementing is performed to: (A) Seal producing zones (B) Place cement between casing and formation (C) Plug abandoned wells (D) Repair casing leaks 20. Which property is most important for cement slurry during placement? (A) High viscosity (B) Low fluid loss (C) High density (D) Low permeability 21. Cement slurry density is usually controlled by adding: (A) Barite or hematite (B) Bentonite (C) Lime (D) Salt 22. The thickening time of cement slurry is defined as: (A) Time required for cement to set completely (B) Time slurry remains pumpable (C) Time taken for cement hydration (D) Time required for curing 23. Which additive is used to accelerate cement setting time? (A) Gypsum (B) Calcium chloride (C) Bentonite (D) Sodium silicate 24. Retarders in cement are added to: (A) Speed up hydration (B) Delay setting time for deep wells (C) Reduce density (D) Prevent gas migration 25. Which test is used to measure cement slurry consistency? (A) Vicat apparatus test (B) Marsh funnel test (C) Fann viscometer test (D) Mud balance test 26. The free water content of cement slurry must be kept: (A) High for easy pumping (B) Zero or very low (C) Equal to mud density (D) Higher than filtrate loss 27. Gas migration after cementing can be reduced by: (A) Reducing mud weight (B) Using cement with good bonding and low permeability (C) Increasing hole size (D) Using oil-based mud 28. The main hydration product of Portland cement is: (A) Calcium hydroxide (B) Calcium silicate hydrate (C-S-H gel) (C) Gypsum (D) Calcium carbonate 29. Secondary cementing is usually performed for: (A) Well abandonment (B) Squeeze jobs (C) Plugging lost circulation zones (D) All of the above 30. The compressive strength of well cement is usually measured after: (A) 12 hours (B) 24 hours (C) 48 hours (D) 7 days 31. Which cement class is most commonly used in oil and gas wells? (A) Class G (B) Class H (C) Class A (D) Class B 32. Lost circulation during cementing occurs when: (A) Slurry flows into weak formations (B) Slurry sets too quickly (C) Mud contamination occurs (D) Casing collapses 33. Spacer fluid in cementing is used to: (A) Remove drilling mud from the annulus (B) Increase cement strength (C) Reduce slurry density (D) Prevent gas migration 34. The main factor controlling cement sheath quality is: (A) Centralization of casing (B) Mud weight (C) Well depth (D) Formation type 35. The API standard testing of well cement is performed at: (A) 25°C and atmospheric pressure (B) Downhole temperature and pressure (C) 38°C and 3.5 MPa (D) 50°C and 5 MPa 36. Which additive increases cement slurry density? (A) Hematite (B) Silica flour (C) Bentonite (D) Lignite 37. Pozzolanic materials in cement are added to: (A) Increase strength and reduce permeability (B) Decrease setting time (C) Improve color (D) Reduce viscosity 38. High-temperature wells require addition of: (A) Silica flour to prevent strength retrogression (B) Calcium chloride to accelerate setting (C) Bentonite to reduce density (D) Hematite to increase weight 39. Cement bond logs are used to: (A) Measure casing thickness (B) Evaluate cement-to-casing and cement-to-formation bonding (C) Check cement density (D) Verify mud removal 40. Which tool is used to separate cement slurry from drilling mud in the casing? (A) Float shoe (B) Cement plug (C) Centralizer (D) Casing collar 41. The term “top of cement” (TOC) refers to: (A) Depth where cement slurry is mixed (B) Depth where cement column ends in annulus (C) Cement placement in surface casing (D) Casing shoe depth 42. The density of neat Class G cement slurry is approximately: (A) 11 ppg (B) 15.8 ppg (C) 18.5 ppg (D) 20 ppg 43. The main cause of poor zonal isolation after cementing is: (A) Channeling of mud or gas through cement sheath (B) Use of silica additives (C) Excessive slurry viscosity (D) Overbalanced drilling 44. Which type of cementing is used to isolate a particular zone? (A) Primary cementing (B) Plug cementing (C) Squeeze cementing (D) Liner cementing 45. In cementing operations, “waiting on cement” (WOC) means: (A) Allowing cement to set and gain strength (B) Pumping cement into casing (C) Preparing cement slurry (D) Removing drilling mud 46. The hydration of tricalcium aluminate (C₃A) in cement produces: (A) Ettringite (B) Calcium hydroxide (C) Silica gel (D) Gypsum 47. Excessive cement slurry free water can cause: (A) Channeling and poor bonding (B) Increased compressive strength (C) Reduced thickening time (D) Higher slurry density 48. In liner cementing, cement is placed: (A) In surface casing only (B) Around a partial casing string (C) In abandoned wells (D) Below the shoe only 49. The main objective of balanced plug cementing is to: (A) Kill the well (B) Place cement at a specific interval inside the wellbore (C) Support surface casing (D) Replace drilling mud 50. API recommends cement testing under: (A) Simulated downhole temperature and pressure conditions (B) Atmospheric conditions only (C) Offshore laboratory standards (D) Ambient conditions FOUNDATIONAL SUBJECTS (Year 1 – Year 2)Engineering Mechanics (Statics & Dynamics) – MCQsFluid Mechanics – MCQsThermodynamics – MCQsComputer Programming (e.g., MATLAB, Python) – MCQsIntroduction to Engineering – MCQsGeology for Engineers – MCQsTechnical Communication – MCQs CORE PETROLEUM ENGINEERING SUBJECTS (Year 2 – Year 4)Introduction to Petroleum Engineering – MCQsPetroleum Geology – MCQsDrilling Engineering – MCQsReservoir Engineering – MCQsProduction Engineering – MCQsPetroleum Fluid Properties – MCQsWell Logging and Formation Evaluation – MCQsPetroleum Economics – MCQsPetroleum Refining and Processing – MCQs Natural Gas Engineering – MCQsEnhanced Oil Recovery (EOR) – MCQsWell Testing – MCQsReservoir Simulation – MCQsDrilling Fluids and Cementing – MCQsOffshore Petroleum Engineering – MCQsHealth, Safety and Environment (HSE) – MCQsPetroleum Project Management – MCQsCorrosion Engineering – MCQsArtificial Lift Techniques – MCQsPetrophysics – MCQs LABORATORIES & PRACTICALS (Theory-based MCQs can be made from these)Drilling Fluids Lab – MCQsCore Analysis Lab – MCQsReservoir Simulation Lab – MCQsRock and Fluid Properties Lab – MCQsWell Logging Lab – MCQs ELECTIVES (Optional/Advanced)Energy Transition and Sustainability – MCQsUnconventional Resources (Shale, Tight Gas, etc.) – MCQsData Analytics in Petroleum Engineering – MCQsGeographic Information Systems (GIS) – MCQsPetroleum Law and Policy – MCQsPipeline Engineering – MCQsRenewable Energy Integration – MCQs