Drift Indicator Systems

Drift Indicator System

Accurate, dependable drift indicator system assures vertical holes

For accurate measurement of deviation from vertical in wellbores, the Forum Drift Indicator System is the most reliable and easy-to-use drift indicator available. This essential tool enables the driller to maintain a controlled, absolutely vertical drill path.

  • Instruments and charts available in 0-7º, 8º, 14º, and 16º values
  • Go-Devil available in 1-5/16 and 1-5/8-inch outer diameter
  • Variety of Go-Devil assemblies available for various methods of running the tool, including free-dropping, sand-lines, and core barrel adapters
  • Standard unit operates in wellbores up to 350º F ( 93º C )
  • Hot Well unit operates in wellbores up to 500º F ( 260º C )
System Components Include
  • Double Recorder — Measures and records hole inclination. Consists of an Angle Indicator and a Timing Device enclosed in a stainless steel case.
  • Go-Devil — Protects the Double Recorder from shock, pressure, and fluid.
  • Various other tools and components, such as rope sockets and Go-Devil sinker weights and stabilizers.
  • Tools for maintaining the Double Recorder.
  • Easy to operate — any member of the crew can read measurement data.
  • Completely mechanical system — requires no liquid or electrical equipment.
  • Reliable, accurate measurement — helps prevent costly deviations from the vertical path.

Double Recorder

Timing Device & Angle Indicator



Electronic Inclination and Azimuth Systems

Records even the slightest changes in the drill angle – as small as fractions of a degree – so the drill path can be quickly and efficiently corrected back to vertical.

Makes maintaining a controlled, absolutely vertical drill path easier than ever.


Streamlines Readings

  • Multiple surveys on a single run – at the push of a button
  • Touchscreen interface on a base unit for quick and easy readings
  • Archive readings for easy tracking of bore hole angle history

Helps ensure accurate, reliable drill paths

  • Tracks clock battery run-time to minimize survey run errors.
  • Sensors are fully temperature-compensated. Temperature changes across the full operating temperature range cause drill angle orientation readings to change by less than 1%.

Guards against loss of crucial drill path data

  • Monitors base voltage level to ensure continuous, trouble-free operation.
  • Archives all surveys in memory so they can be viewed and re-printed at any time.
  • Includes a diagnostic LED that indicates whether the tool is operating properly.
  • Recovers survey data even after power loss or loss of communications with the tool .
  • Provides administrative options that enable system managers to set users/passwords and to protect access to certain functions.
  • Includes security features that protect survey data.

Provides easy, versatile access to drill path data

  • Ethernet port
  • Enables remote control and monitoring via LAN or a Web browser.
  • Makes it possible to download data via FTP.

Integrates easily with existing mechanical drift indicator equipment

  • Fits in existing 1-inch running gear – and can be run in tandem with mechanical clocks.
  • Color touchscreen display
  • Easy-to-use interface
  • Rugged weather-proof case and connectors
  • Thermal printer – no ink to replace
  • Base unit run-time approximately 8.5 to 9.5 hours with full charge
  • Clock run-time approximately 200 hours with new battery
  • Maximum survey time approximately 9 hours
  • Maximum number of survey runs (with 9-hour surveys) approximately 22. Shorter survey times yield more survey runs.
  • Maximum number of individual surveys per run: 1,024
  • Battery-operated, with charger
  • Operating temperature range: From -40 degrees Celsius to greater than 125 C (-40 to 257 F)
  • Inclination range: 0 to 180 degrees
  • Orientation range: 360 degrees full scale, all axes
  • Orientation/inclination resolution: 0.02 degrees
  • Repeatability:
    • Inclination: 0.10 degrees
    • Heading: 0.5 degrees
  • Accuracy:
    • Inclination: 0.2 degrees
    • Heading: 0.5 degrees typical for static test conditions; plus/minus 2 degrees typical for dynamic (cyclic) test conditions and for arbitrary orientation angles
  • Variety of Go-Devil assemblies available for various methods of running the tool, including free-dropping, sand-lines, and core barrel adapters