Definition(s)
Closing Unit
The assembly of pumps, valves, lines, accumulators, and other items necessary to open and close the BOP equipment.
Source: API RP 59, Recommended Practice for Well Control Operations, Second Edition, May 2006. Global Standards
Closing Unit
The assemblage of pumps, valves, lines, accumulators, and other items necessary to open and close the BOP equipment and diverter system.
Source: API RP 64, Recommended Practice for Diverter Systems Equipment and Operations, Second Edition, November 2001 (March 1, 2007). Global Standards