A downhole tool (composed primarily of slips, a plug mandrel, and a rubber sealing element) that is run and set in casing to isolate a lower zone while an upper section is tested, cemented, stimulated, produced, or injected into. In order to facilitate removal by drilling, a bridge plug is often made of cast iron and is commonly referred to as a cast iron bridge plug (CIBP).
Source: API BULLETIN E3, Environmental Guidance Document: Well Abandonment and Inactive Well Practices for U.S. Exploration and Production Operations, First Edition, January 1993 (Reaffirmed June 2000). Global Standards
Mechanical device installed in, and used for blocking fluid (liquid or gas) communication in, the conduit and not installed in a designed receptacle.
Source: API SPEC 11D1, Packers and Bridge Plugs, Upstream Segment, Second Edition, July 2009. Global Standards