Page 60 - Practical Well Planning and Drilling Manual

Section 1 revised 11/00/bc 1/17/01 2:55 PM Page 36

[ ] Well Design
1.3.6

It is recommended that when considering the stresses acting on a
completion tubing string, a computer program should be used to easi-
ly analyze the design and consider different scenarios. However, the
engineer should always confirm the results by comparing them with
some basic manual calculations. Few programs are perfect and it only
takes one mistyped digit to render the computed analysis inaccurate.
Worse, if you assume it is a good design when there is a fatal flaw, it
may fail catastrophically in service.
The various methods for calculating physical forces on tubing and
relating this to strength requirements are the same as they are in casing
design. These topics are covered in the following Section 1.4 and may
be used as reference for tubing.

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