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essence, completion consists of deciding on the characteristics of
the intake portion of the well in the targeted hydrocarbon
formation. There are a number of types of completions, including:
 Open hole completions are the most basic type and
are only used in very competent formations, which are unlikely to
cave in. An open hole completion consists of simply running the
casing directly down into the formation, leaving the end of the
piping open, without any other protective filter.
 Conventional perforated completions consist of
production casing being run through the formation. The sides of
this casing are perforated, with tiny holes along the sides facing
the formation, which allows for the flow of hydrocarbons into the
well hole, but still provides a suitable amount of support and
protection for the well hole. In the past, 'bullet perforators' were
used. These were essentially small guns lowered into the well that
sent off small bullets to penetrate the casing and cement. Today,
'jet perforating' is preferred. This consists of small, electrically
ignited charges that are lowered into the well. When ignited, these
charges poke tiny holes through to the formation, in the same
manner as bullet perforating.
 Sand exclusion completions are designed for
production in an area that contains a large amount of loose sand.
These completions are designed to allow for the flow of natural
gas and oil into the well, but at the same time prevent sand from
entering the well. The most common method of keeping sand out
of the well hole are screening, or filtering systems. Both of these
types of sand barriers can be used in open hole and perforated
completions.
 Permanent completions are those in which the
completion, and wellhead, are assembled and installed only once.
Installing the casing, cementing, perforating, and other completion
work is done with small diameter tools to ensure the permanent
nature of the completion. Completing a well in this manner can
lead to significant cost savings compared to other types.
 Multiple zone completion is the practice of
completing a well such that hydrocarbons from two or more
formations may be produced simultaneously, without mixing with

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