Fishing In Drilling Oil & Gas Operations Full Guide
A fish is defined as any undesirable tool, piece of equipment, or other object found in the cased or uncased wellbore that stops or retards routine operational progress. Fishing in drilling oil and gas wells industry can be defined as any operation required to remove undesirable objects (the fish) from the wellbore.

Fishing requires the use of specialized procedures and equipment to remove, retrieve, or well sidetrack a fish so that normal drilling or completion operations may continue.
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