One current component of a lightning flash. The number of strokes per flash is typically three to four, but may be as low as one or as high as 30 (Uman, All About Lightning, p. 41).
Source: API RP 545 Recommended Practice for Lightning Protection of Aboveground Storage Tanks for Flammable or Combustible Liquids, First Edition, October 2009. Global Standards
Total vertical movements (upward and downward) of the riser relative to the vessel which is also the travel of the riser tensioner.
- NOTE: Stroke is affected by environmental loads, functional loads (i.e. top tension, temperature and mean static vessel offset) and pressure.
Source: API Standard 2RD, Dynamic Risers for Floating Production Systems, Second Edition, September 2013. Global Standards
Total upward and downward vertical movements of the riser relative to the vessel, i.e. travel of the riser tensioner, draw works and slick joint.
- NOTE: It includes effects from environmental loads, functional loads (i.e. top tension, temperature and mean static vessel offset) and pressure.
Source: API RP 17G, Recommended Practice for Completion/Workover Risers, Second Edition, July 2006 (Reaffirmed April 2011). Global Standards