Light well intervention systems
Subsea LWI systems can be defined as those systems which provide some form of direct access to the wellbore, without requiring the use of an offshore drilling unit or a standard drilling marine riser. A wide variety of such systems have been developed, including conventional rigid workover risers, subsea wireline systems and reeled tubing systems as described in the following subclauses. Other subsea LWI systems are also feasible and may be deployed in the future, e.g. flexible riser systems.
Source: API RP 17A, Design and Operation of Subsea Production Systems—General Requirements and Recommendations, Fourth Edition, Reaffirmed 2011. Global Standards