Circulation System

IPM

CIRCULATION SYSTEM

IPM IDPT

Circulation System

IPM

The Drilling FluidThe drilling fluid is a mixture of various components

The functions are1. Provide hydraulic horse power to the bit2. Transport cuttings out of the hole3. Support well bore4. Prevent entry of formation fluids into the well bore5. Cool and lubricate the bit and drill stem

Basically three types of drilling fluids1. Water based drilling fluid2. Oil based drilling fluid3. Air or gas based drilling fluid

Circulation System

IPM

Preparation and Treatment

The four major routines are1. Initial Preparation2. Weight up (increase the mud weight)3. Water back/Dilution (reduce the mud weight)4. Break over/Treatment (change the chemistry of the mud)

Mixing Jet Hopper

A funnel shaped device to rapidly add Solid materials to drilling fluid by Vacuum principle

Circulation System

IPM

TestingThe two major variables that are constantly monitored are

Mud weight using a mud balance

and

Viscosity using a Marsh funnel

Circulation System

IPM

Circulating EquipmentConsists of

1. Suction pits2. Suction line3. Mud pumps4. Discharge line5. Stand pipe6. Rotary hose7. Drill Stem8. Annulus9. Return line10. Settling tanks11. Conditioning area

Circulation System

IPM

Triplex Mud PumpCalled the HEART of the Circulation System

Circulation System

IPM

Triplex Mud Pump

Circulation System

IPM

Pump Manifold

Circulation System

IPM

Discharge Dampener

Absorbs discharge pressure surges

Thus permits smoother volumetric output

In turn minimizes vibrations

Installed close to the pump

Nitrogen is used to charge the dampener

Circulation System

IPM

Charging Pump

Supplies drilling fluid to the mud pump

Is on the suction line of the mud pump

Centrifugal Type

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IPM

Pump Module

Circulation System

IPM

Liners and Pistons

Fluid End

Power End

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IPM

Liners and Pistons

Two dimensions are

Stroke Length and Diameter

Theoretical volumetric output is calculated

Volumetric Efficiency is normally 97 to 98%

Actual volumetric output is thus calculated

Circulation System

IPM

Valves and Seats

Circulation System

IPM

Pump Output Exercise

Stroke Length 12”

Liner Diameter 6”

Find pump output per stroke

Circulation System

IPM

Solids Control Equipment

Shale Shaker Desander/DesilterThe first cleanerRemoves the biggest particlesVibrating screens

Many cone shaped cylindersRemoves the smaller particlesCentrifugal force

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Conditioning Equipment

Vacuum De-Gasser

Removal of GasGasses entrained in the mud need to be removed because1. They reduce the density2. Reduce the pump efficiency3. Decrease hydrostatic pressure4. Increase drilling fluid volume

Two types of equipment is used

And

Mud Gas Separator

Circulation System

IPM

Drill String and Annular Volumes

DArea (in sq) = D x 0.785

2

Volume in bbl/ft = D1029.4

2

Dd Annular Volume in bbl/ft = D2 d 2

1029.4

Annulus - The space between drill string and holeAnnular Volume - The volume of this space

Annulus

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IPM

Hole Volumes

Drill Collar

Drill PipeID of drill pipe = d1OD of drill pipe = D1Length of drill pipe = l1

ID of drill collar = d2OD of drill collar = D2Length of drill collar = l2

Hole Size = D3

All volumes are in barrels

A = DP inside volume (capacity) = l1 x d1 / 1029.4

B = DC inside volume (capacity) = l2 x d2 / 1029.4

C = Annular volume around DC = l2 (D3 – D2) / 1029.4

D = Annular volume around DP = l1 (D3 – D1) / 1029.4

Total Hole (well) volume = A + B + C + D (bbl)

2

2

2

2

2 2

Circulation System

IPM

Practice Work on Volumes

Hole Size – 8 ½”Drill Collar – 6 ½” OD, 2 ¼” ID, 650 feetDrill Pipe – 5”, 4 ¼” IDHole depth – 8200 feet

What is the volume of this well in bblHow many strokes to pump this volume

Circulation System

IPM

Practice Work on Volumes

Hole Size – 8 ½”Drill Collar – 6 ½” OD, 2 ¼” ID, 850 feetDrill Pipe – 5”, 4 ¼” IDHole depth – 8400 feetCasing Shoe – 3000 feetCasing Details – 9 5/8”, 53.5 ppf,

What is the volume of this well in bblHow many strokes to pump this volume

Circulation System

IPM

Hydrostatic Pressure

In which vessel is the hydrostatic pressure the highest

They are the same in all cases

BECAUSE

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Hydrostatic Pressure

Hydrostatic Pressure is a function of vertical depth and density

Hydrostatic pressure in a well = 0.052 x TVD x Mud Weight

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Hydrostatic Pressure

6240 psi 7800 psi 5616 psi 6058 psi

Circulation System

IPM

SLUG

ORIGINAL MUD

HEAVY MUD - SLUG

DRILLPIPE

ANNULUS

SLUG

EMPTYPIPE

SLUG IS PUMPED SO AS TO PROVIDE A LENGTH OF DRY PIPE DURING POOH

Circulation System

IPM

Practice Work on Slug

Hole Size – 8 ½”Drill Collar – 6 ½” OD, 2 ¼” ID, 850 feetDrill Pipe – 5”, 4 ¼” IDHole depth – 8400 feetCasing Shoe – 3000 feetCasing Details – 9 5/8”, 53.5 ppf,

MW – 10ppg Slug Wt – 12ppg

How much slug to have 300 feet of dry pipe