Derrickman Interview Questions & Answers

Question 1. What Is The Function Of Mud?

Answer :

• cool and lubricate the drilling bit
• carry cutting from the bottom of the hole to the surface
• Drilling mud know as hydrostatic pressure which allow to control
• the formation pressure
• Clean drill bits ,drilling mud removes cutting from bit teeth which
•   prevent bit ball up situation
• prevent formation damage by using suitable drilling mud
• Transmit hydraulic horsepower to the bit
• To avoid bit to balled up

Question 2. What Is The Functions Of Shale Shaker,desander,degasser,mud Cleaner,deselter And Center Fuger?

Answer :

Shale shaker: remove big cutting from mud (74 micron

Desander: remove sand from mud less than (74 -40micron  working pressure (35-45) psi. capacity 500gpm/cone

Deselter : remove salt from mud less than (40 - 20 micron

Working pressure (35-45) psi. capacity 75 gpm/cone

Degasser : remove gases from mud.working pressure (35-45) psi

Mud cleaner : remove cutting from 20 micron to 7 micron

Capacity 75gpm/cone

Center fuger :remove cutting from mud less than 7 micron to 4

micron

Question 3. How Many Tanks You Have On Rig?

Answer :

shaker tank-suction tank-reserve tank-trip tank-intermidate tanke mixing tank

Question 4. What Is Function Of Trip Tank?

Answer :

It is used to check the well for losses or gain during tripping or wire line operation

Question 5. What Are The Steps To Check On Mud Pump?

Answer :

• Permit to work
• Per job safety meeting
• Electric isolation and put safety lock behind pump
• Close discharge valve - open bleed valve -then close suction valve
• Check pump and replace parts
• Remove tools from pump area
• Open discharge valve-closed bleed valve-open suction valve
• Remove safety lock and isolation
• Cleen cooling tank and fill it
• close work permit

Question 6. What Difference Between Sweep And Spot

Answer :

• High viscous mud to circulate hole cleen
• High viscous mud to put on bottom before trip

Question 7. Why We Using Cooling System In Mud Pump?

Answer :

To cooling pistons ,liners ,seats

Question 8. When You Need To Change Valve In Pump?

Answer :

Having cracked valve or change seat

Question 9. When You Need To Change Piston In Pump?

Answer :

Having cracked piston or change liner

Question 10. What Are P.p.e Using While Mixing?

Answer :

Rubber shoes,rubber gloves,helmet,apron,control

Question 11. What Is Slug Mud?

Answer :

Heavy mud using berfore triping out to save mud and cleen pipes

Question 12. What Are The Steps To Cleen Mud Tanks?

Answer :

• Work permit
• Measure gases with multi gas detector
• Clean tanks
• Close work permit

Question 13. What Time Of Greasing Crown?

Answer :

Every day

Question 14. How You Can Calculate Mud Tank Size?

Answer :

Lenth* width* height =…/5.614 =…. bbls

Question 15. What’s The Hydro-static Pressure?

Answer :

Ph is the pressure exerted by the weight of a liquid on its “container

Ph is the pressure exerted by the drilling fluid to offset the pressure exerted by the formation fluid

Ph (PSI) = 0.007 * TVD (ft) * Mud wt. (pcf)

Ph (PSI) = 0.052 * TVD (ft) * Mud wt. (ppg)

Sufficient hydrostatic pressure is required to prevent the borehole wall from caving in and to keep formation fluid from entering the wellbo

Question 16. What Is The Relationship Between The Water Losses And Filter Cake?

Answer :

Filter cake increase with water losses increase

Question 17. What Will Happen When Sand Found With Drilling Mud?

Answer :

• Damage in pump parts
• Rig down time
• Cause bit nozzle plug
• Reduce rate of penetration