Schlumberger

Isolation Valves

ISO 28781 and API 19V are international standards that prescribe the requirements for subsurface barrier valves and related equipment for use in the petroleum and natural gas industries. Subsurface barrier valves provide a means of isolating the formation or creating a barrier in the tubular to facilitate the performance of well operations before production or injection starts. Barrier valves are also available for the postproduction or postinjection phase.

The standards define

  • functional characteristics
  • product material requirements
  • quality control, defined by quality grades Q1 and Q2
  • design criteria
  • design validation, defined by qualification levels V1, V2, and V3
  • design changes
  • documentation requirements—operations manuals and product identification.
Validation Grade Test Medium Flow Rate At
200 psi Across Barrier 50% Rating 100% Rating
V1 Liquid 10 ml/min 5 ml/min 5 ml/min
V1 Gas 1 ft3/min 0.5 ft3/min 0.5 ft3/min
V2 Liquid 30 ml/min 15 ml/min 15 ml/min
V2 Gas no requirement
V3 Supplier/manufacturer-defined and successful field history of 20 similar valves


ISO 28781 and API 19V define barriers

Barrier from Above Barrier from Below Barrier from Above
and Below
Preproduction and preinjection barrier valves Type A Type B Type C
Postproduction and postinjection barrier valves Type AA Type BB Type CC

Manage Debris Accumulation in Harsh Environments

FORTRESS isolation valve
The FORTRESS isolation valve withstands severe debris environments and optimizes the available actuation energy—predictably, consistently, and reliably. Visit FORTRESS valve page

More than 2,300 Isolation Valves Installed Worldwide

 Formation Isolation Valves
Formation isolation valves provide a reliable barrier and contain fluids during completions and workover operations.
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