1. n. [Well Workover and Intervention]

The design, strategies and principles for ensuring that there is uninterrupted hydrocarbon production flowing from the reservoir to the point of sale. Impediments to hydrocarbon flow in wellbores and flowlines may arise from an interrelated combination of effects involving flow dynamics—single and multiphase fluid flow—and production chemistry. At reservoir pressure and temperature conditions, fluids are single phase. As they travel toward the production facility, the fluids experience changes in pressure and temperature that result in multiple fluid phases and the formation, accumulation and dispersal of inorganic and organic solids that may become impediments to production. Multiphase flow may cause phenomena such as slugging in subsea flowlines and risers. Solids deposition may cause flowline plugging anywhere in the system.

Historically, production impediments in wellbores and flowlines are well-known in onshore and shallow water environments, where they have been managed using thermal, mechanical and chemical means. The long flowlines connecting a wellhead or manifold to a production facility are exposed to low temperatures and high pressures. In these deepwater environments, intervention technologies and operations are expensive because they typically require deepwater vessels or a rig. Personnel responsible for flow assurance should have advanced knowledge of flow dynamics and production chemistry.