Well-Site Operations
A Brief Overview
By: Mohamed Elfateh
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Well site Operations
Part I:Introduction
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Well site Operations
qIntroduction:
vWell Classifications.
vDrilling Rig Types.
vRig Components.
vCirculation system.
vDrilling Fluid.
vSolid Control Equipment.
v Well-Site Crew Organization
v HSE.
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Well site Operations
vWells Classifications:
ØPurpose :
§ Exploration (Wildcat): Drilled in an area that has not been explored
before. (No offset wells, very little geological and pressure data
available).
§ Appraisal: Drilled to determine how large the reservoir is. (Some
offset wells always available).
§ Development: Drilled to enter a known productive portion of the
reservoir. (Good offset data available) & Infill Wells.
ØProfile :
§ Vertical, Deviated, Horizontal or Multilateral.
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vDrilling Rig Types:
Well site Operations
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vDrilling Rig Types:
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Well site Operations
v Drilling Land Rig Components:
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Well site Operations
Rigging Up
R/U
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Well site Operations
vDrilling Rig Components:
Hoisting System:
Draw Work.
Crown & Traveling Blocks.
Drill Line (Fast line).
Hook.
Dead line anchor.
supply Reel.
Circulating System:
Suction Tank.
Mud Pumps.
Standpipe.
Rotary Hose.
Drilling String.
Flow Line.
Solid Control Equipment.
Intermediate Tank. 9
Well site Operations
• Rotating System:
• Rotary Table/Kelly.
• Top Drive System TDS.
• Down hole Motor.
• Power System:
• Generator Sets.
• S.C.R & VFD.
• Control Room.
• Well Control System:
• BOP Stack.
• Accumulator (Koomy) Unit.
• Gas Separator & Vacuum Degasser .
• Choke &Kill Manifold.
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Well site Operations
§ The Drilling String:
• Bottom Hole Assembly (BHA)
• Bit & Sub Bit
• Drill Collars
• Drill Pipe
• Heavy Weight Drill Pipe (HWDP)
• Special Tools (drilling jars, bypass tools, shock subs, BHA
etc.)
Rock Bit PDC Combination
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Well site Operations
Circulating System
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Well site Operations
vDrilling Fluid:
It is a mixture of liquids and chemicals that allow the drilling and completion of a well.
Drilling Fluid (mud):
• Water-based(Fresh/ Brine)
Cost-effective, easy to handle
Shale sensitive
• Oil-based
Non-reactive (inert)
Expensive, environmental impact
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Well site Operations
• Water base mud is used in Sudan oil fields, These involve the following types:
Bentonite, KCL polymer, KCL Silicate designed based on both Geological and
Operational Problems of each section in the Well.
• Functions of drilling Mud:
qControlling subsurface pressure HP Vs FP (mud density MW).
qCuttings removal (viscosity FV, PV).
q Suspending cuttings when circulation is stopped (gel strength & YP).
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Well site Operations
qProviding an impermeable wall cake (Mud
filtrate).
qActing as medium for electrical well logging(PH
& Salinity).
qMinimizing clay swelling (Mud Inhibition).
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Well site Operations
vSolid Control Equipment:
• Shale shaker.
• Degasser.
• Desander.
• Desilter.
• Centrifuge.
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Well site Operations
• Shale shaker They are the first phase of a solids control system on a
drilling rig, and are used to remove large solids (cuttings) from the drilling
fluid ("mud").
• A degasser is a device used to remove gasses from drilling fluid which
could otherwise form bubbles.
• Desanders and desilters are solid control equipment with a set of
hydrocyclones that separate sand and silt from the drilling fluids in drilling
rigs. Desanders are installed on top of the mud tank following the shale
shaker and the degasser, but before the desilter. Desander removes the
abrasive solids from the drilling fluids which cannot be removed by shakers.
Normally the solids diameter for desander to be separated would be
45~74μm, and 15~44μm for desilter.
• A centrifuge is an industrial version of the device that separates fine silt
and sand from the drilling fluid. It is typically mounted on top or just off of
the mud tanks.
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Well site Operations
v Well-Site Crew Organization
Client Representative
Drilling Supervisor Geological Supervisor
Mud logging
Rig Crew Crew
Drilling Fluid Wireline Crew
Crew
Cementing Coring Crew
Crew
Directional LWD
Drilling Crew 18
Well site Operations
v Rig Personnel:
1. Rig Manager.
I. Rig Engineer.
II. HSE Engineer.
III. Mechanical Engineer.
IV. Electrical Engineer.
V. Tool pusher.
VI. Driller.
VII. Assistant Driller.
VIII. Derrick man.
IX. Floor man.
X. Roughneck.
XI. Welder.
XII. Technicians.
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Well site Operations
v Health Safety & Environment (HSE)
§ Rig safety equipment:
A drilling site is equipped with various safety features, including
I. First aid kits.
II. Fire extinguishers.
III. Emergency air supplies.
IV. Warning sirens.
V. Gas monitors.
VI. Wind indicators (wind sock).
The location of this equipment and Muster Points should be noted prior to
an emergency since emergency conditions can be noisy and can be made
more dangerous by limited visibility and confusion.
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Well site Operations
§ Personal Protecting Equipment: includes the following:
• Hard hat.
• Safety shoes.
• Safety glasses.
• Hearing protection.
Special Equipment:
• SCBA:
Self-Contained-Breathing-Apparatus.
• The following are recommended:
• Well-fitted, protective clothing
• CPR and first aid training.
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Well site Operations
§ Rig site Evacuation plan and Safety Signs:
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