Bai giang pttkk drilling fluid circulation system

01/2018 1

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Drilling Fluid Circulation Systems

1. Introduction

2. Mud Pumps

Duplex PDP & Triplex PDP

3. Solids removal

4. Solid Control Equipment

4.1. Shale shakers

4.2. Degasser

4.3. Mud Cleaners

5. Treatment and Mixing Equipment

References

1. (CDF) Jorge H.B. Sampaio Jr. “Drilling Engineering

Fundamentals.” Master of Petroleum Engineering. Curtin

University of Technology, 2007. Chapter 2

2. (WEC) Rabia, Hussain. “Well Engineering & Construction”. Entrac

Consulting Limited, 2002. Chapter 7 & 16

01/2018 2

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Introduction

01/2018 3

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Drilling Fluid Roles

✓ The drilling fluid plays several functions in

the drilling process.

✓ The most important are:

➢clean the rock fragments from beneath the bit

and carry them to surface

➢exert sufficient hydrostatic pressure against the

formation to prevent formation fluids from

flowing into the well

➢maintain stability of the borehole walls

➢Cool and lubricate the drillstring and bit.

01/2018 4

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Drilling Fluid Circulation

✓ Drilling fluid is forced to circulate in

the hole

➢ at various pressures and

➢ flow rates

✓ Drilling fluid is stored in steel tanks

located beside the rig

✓ Powerful pumps force the drilling

fluid through surface high pressure

connections to a set of valves called

pump manifolds located at the

derrick floor.

01/2018 5

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Drilling Fluid Circulation (Cont)

✓ From the manifold, the fluid

goes up the rig within a pipe

called standpipe to

approximately 1/3 of the height

of the mast.

✓ From there the drilling fluid flows

through a flexible high pressure

hose to the top of the drillstring.

➢ The flexible hose allows the fluid

to flow continuously as the

drillstring moves up and down

during normal drilling operations.

01/2018 6

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Swivel

✓ The fluid enters in the

drillstring through a special

piece of equipment called

swivel located at the top of

the kelly.

➢ The swivel permits rotating

the drillstring while the fluid

is pumped through the

drillstring.

01/2018 7

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Drilling Fluid in Wellbore

✓ In wellbore

➢ The drilling fluid then flows down the

rotating drillstring and jets out through

nozzles in the drill bit at the bottom of the

hole.

➢ The drilling fluid picks the rock cuttings

generated by the drill bit action on the

formation.

➢ The drilling fluid then flows up the borehole

through the annular space between the

rotating drillstring and borehole wall

01/2018 8

Đinh Công Vĩnh Luân – MSc in Offshore Engineering

Email: [email protected]

Drilling Fluid at Surface

✓ At surface

➢ At the top of the well (and above the

tank level), the drilling fluid flows

through the flow line to a series of

screens called the shale shaker.

❖ The shale shaker is designed to separate the

cuttings from the drilling mud.

❖ Other devices are also used to clean the

drilling fluid before it flows back into the

drilling fluid pits.