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U
Upset (Mechanical)
A
digester in an upset condition is sometimes called a “sour” or “stuck”
digester.
Upset (Mechanical): An enlargement in the string, usually for cutting
threads. May be internal or external upset.
Up Steam: In the uid path before the point of interest.
Upstream: Oil and natural gas exploration and production activities, plus
gas gathering, processing, and marketing operations.
UR: See Underreamer.
Uranium: U-238, one of the natural isotopes that as a trace element may
incorporate into the matrix of naturally forming barium or strontium sulfate
scale and make it a very low-level radioactive material ...