Permanent Downhole Gauges

Metris systems—not yesterday’s downhole gauges

Schlumberger permanent downhole gauge technology has evolved from transmit-only devices providing pressure and temperature (PT) measurements at fixed time intervals into interactive systems that enable users to actuate a wide range of downhole completion equipment by using just one electric and two hydraulic lines.

Gauges belonging to the new family of Metris permanent monitoring systems use a single acquisition and diagnostics card that employs frequency division multiple access (FDMA) telemetry—also used by cellular telephones—for bidirectional communication to accommodate dynamic conditions. The card and telemetry combination enables

• acquisition of PT measurements
• immunity from any electromagnetic noise (e.g., from an ESP or other AC-powered devices)
• deployment of more gauges on one monoconductor cable
• elimination of limitations on distance between gauges
• selective hydraulic actuation
• prognostic health monitoring (PHM) of subsurface safety valve actuation
• gauge, connector, cable, and acquisition system diagnostics.

Metris systems are a key component in intelligent completions systems, which maximize flexibility, simplify well design, increase reservoir contribution control using downhole interval control valves and reduce installation time and complexity. Intelligent gauges are the future, and the future is now.