STANDARD HANDBOOK OF PETROLEUM & NATURAL GAS ...

698 Drilling and Well Completions
Table 4-58
Drilling Fluids: General Trouble Shooting [25]
Problem Symptoms Treatment
1. Mud Properties Mud weight too low; low
Mud weight
viscosity
Mud weight too low;
viscosity controlled
Mud weight too high
Viscosity
Filtration
Mud foaming
2. Contaminations
Drilled solids
Cement
Gipsum or anhydrite
Funnel viscosity too high;
high PV; high gels and
high solids
High funnel viscosity, high
YP, high gels; normal PV
and solids
Fluid loss too high, viscosity
can be increased
Fluid loss too high, viscosity
controlled
Fluid loss too high; thick,
soft filter cake; low
Methylene Blue Test.
Treatment with filtration
agent does not help
Foam on surface at mud
pits. No reduction in mud
weight
Reduction in mud weight.
Increased funnel viscosity.
Pump pressure drops.
Internal foam
High viscosity and gel
strength, slow drilling rate,
chemical treatment
ineffective
High viscosity, gel strength,
increase in pH, water loss
and filtrate calcium.
High viscosity, high flat gel
strength; increased water
loss, filtrate calcium and
sulfate
Add weighting material and
bentonite
Add weighting material,
bentonite and thinner
Run mechanical solids
removal equipment. Dilute
with water or thin with
thinner
Run mechanical solids
removal equipment, dilute
with water
Add thinner
Treatment with filtration
control agent
Treatment with thinner and
filtration control agent
Add bentonite to the system
Spray water or diesel over
the pit surface, use
defoamer. Check surface
system for air entraintment.
Use defoamer. Thin the mud
to reduce yield point.
Consult mud service
engineer.
Dilute with water, make use
of solids removal
equipment. Displace mud.
Chemical treatment: (1) Bicarb
NaHCO,, (2) Thinner.
If large concentration of
Ca ionschange to an
inhibitive mud
Chemical treatment; soda
ash Na,CO, (0.02 ppb at
soda ash for every epm of
hardness) for drilling
massive anhydrite change
to gip mud.