Mud Systems

1
Lesson 3

• Mud Systems

2
Mud Systems

• Read MI Chapters 3, 5
• Multimedia Program 3 4

3
Mud systems

• Diagnostic tests
• Water based muds
• Oil based muds
• Additives
• Mud handling system

4
Diagnostic tests

• API recommended mud tests were devised to help
  the mud engineer determine whether the drilling
  fluid is performing its functions properly.

5
Diagnostic tests

• Mud Balance Density of mud
• Marsh Funnel Consistency of mud

6
Diagnostic tests

• Rotational Viscometer
• Measures Rheological properties of mud
• Rheology is the study of the flow characteristics
  of a drilling fluid and how these characteristics
  affect movement of the fluids
• From this info the circulating system can be
  designed or evaluated regarding how it will
  accomplish certain desired objectives.

7
Rotational Viscometer

• Dimensions of bob and rotor are chosen so that
  the dial reading at 300 rpm is equal to the
  apparent Newtonian viscosity in cp.

8
Rotational Viscometer

• Bingham plastic fluids
• PV, cp - measure of internal resistance to fluid
  flow resulting from the interactions of solids in
  the drilling fluid
• YP, lbf/100 sq. ft. - measure of the internal
  resistance of a fluid to initial flow.
• Gel, lbf/100 sq. ft. - measure of electrical
  attractive forces within the drilling fluid under
  static conditions

9
Rotational Viscometer

• Power law
• K is a measure of the thickness of the fluid
• n is a measure of the deviation from Newtonian
  fluid behavior.

10
Diagnostic tests

• pH Determination

11
Diagnostic tests

• API Filter press - measure filtration rate and
  filter cake thickness

12
Diagnostic tests

• HTHP filter press - measure filtration rate and
  filter cake thickness at higher differential
  pressures and temperatures

13
Diagnostic tests

• Chemical Analysis - Test for
• OH-, Cl-, Ca
• Alkalinity - Pf, Pm, Mm, Mf
• Designed to establish the concentration of
  hydroxyl, bicarbonate, and carbonate ions in the
  aqueous phase of the mud.

14
Diagnostic tests

• Chloride Concentration - is salt present
• Water Hardness
• Sand Content - Effectiveness of solids control
  equipment

15
Diagnostic tests

• Mud Retort - volume fraction of oil, water, and
  solids in mud
• Cation Exchange Capacity of Clays - volume
  fraction of low gravity solids

16
Pilot Tests

• Use samples of 350 ml of mud.
• 350 ml is called one barrel equivalent

17
Pilot Tests

• Vt V1 V2 Vn
• Vi mi/ ri
• r (m1 m2 mn)
• (V1 V2 Vn)

18
Water based muds

• Water is the basic component
• Clays are added for viscosity
• Yield of clay is defined as the number of bbls of
  mud that can be produced using 1 ton of clay if
  the mud has an apparent viscosity of 15 cp at 600
  rpm.

19
Water based muds

• Wyoming bentonite is the most common used in
  fresh water muds and is considered high yield
  clay - mostly sodium montmorilloonite.

20
Water based muds

• Attapulgite is used as salt water gel

21
Water based muds

• Barium sulfate - barite is most common solid
  added to muds to increase density.
• Hematite (iron ore) is sometimes used also

22
Inhibitive water based muds

• A mud in which the ability of active clays to
  hydrate has been reduced greatly.
• Used to prevent drilled clays from disintegrating
  into very small particle and entering the mud.
• Used to stabilize high clay content formations

23
Inhibitive water based muds

• Calcium treated muds
• Lignosulfonate treated muds
• High salinity muds

24
Oil based muds

• Continuous phase is composed No. 2 diesel.
• Emulsifiers are added to prevent water droplets
  to coalesce and settling out of the mud
• Water droplets are used to build viscosity and
  for filtrate control, as is asphalt, polymers, etc

25
Mud Selection Criteria
26
Additives
27
Mud handling system