Single Zone Completion
Flowing wells equipped with a single tubing string are usually completed with a packer. Single-zone completions may involve the downhole commingling of production from several intervals within that zone. Examples of single-zone completions are shown in Figure 1.

At the design stage, optimum tubing size for maximum long-term flow rate, future artificial lift needs, and future workover operations should be considered.

Figure 1 Single zone completion

Tubingless Casing Flow.
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