Page 45 - Practical Well Planning and Drilling Manual

Section 1 revised 11/00/bc 1/17/01 2:55 PM Page 21

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1.3

Precompletion and Completion Design

“Precompletion” covers the well requirements that need to be
met after drilling operations have ceased and before running the
completion string. Precompletion will cover pre-installed downhole
sand control measures (such as gravel packs), packers run before the
tubing, etc.
“Completion” covers the tools and tubing that are run in as part
of the production tubing string. This will include completion-run
sand control measures (such as screens), downhole safety valves, etc.
The type of completion run will be determined by the production
needs of the well. Size of tubing, types of connections, accessories to
run, etc. will depend on factors such as fluids produced, gas/oil ratio
(GOR), production potential, tertiary recovery techniques planned,
sand control requirements, etc.
Casing sizes should be no larger than that required by formation
evaluation requirements and drilling and production equipment sizes
in order to drill cost-effective wells that are fit for purpose. Sizing
down a conventional well by one casing size can save over 20% on the
drilled well cost. A production well traditionally drilled to total depth

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