Special Projects

Sensorlink has years of experience applying different technologies for monitoring pipes and steel structures.The products and concepts are developed through customized projects. Sensorlink develops solutions in close collaboration with its customers according their immediate needs.

If you have any questions or projects where you think Sensorlink might be of assistance, don’t hesitate to contact us by phone or email. Contacts can be found at the front page or you can send us an email at mail@sensorlink.no

Piston Track®

Experts in ultrasonic technology

Unintentional lock-up or bottoming out of the heave compensator on a floating drilling rig has potentially serious consequences, particularly when the rig is rigidly attached to the wellhead. The situation can be very dangerous for rig personnel, and often leads to serious equipment damage.

Similar risks of equipment damage and down time are encountered when landing and installing blow out preventers (BOP). Solutions to these problems are now available with the PistonTrack® system.

PistonTrack® is used for monitoring the heavy compensator systems on floating drilling rigs, and works by an electromagnetic measurement principle. A sensor array is mounted on the outside of the compensator, and information from the sensors is then processed and consolidated to determine the position and velocity of the floating piston inside the compensator.


    Safer Operations

    Heave compensating systems are used on most floating drilling vessels to decouple the drillstring from the vertical motion of the rig. During critical operations, for instance well testing and BOP landing, compensator lock-up may cause disaster.

    PistonTrack is not affected by changes in the composition of accumulator fluids due to rough operating conditions, as has been experienced in other systems.

    Well-defined Graphics

    The graphical display has been designed to give the driller a real-time, clear and intuitive picture of the accumulator’s position and movement. The information is presented as a bar graph with gas, piston and liquid indicated with colors and a trend line showing the position for the last 2.5 minutes.

    PistonTrack® is based on the advanced electronics and software, and is suited for remote diagnostics, maintenance, and upgrade (ready for e-field and integrated operations).

    Efficient Installation

    PistonTrack® can be installed on all types of drilling rigs. It is suitable for new-build or retrofit on existing installations with:

    • Cylinder-based draw works.
    • Top compensator.
    • Wireline and cylinder-based riser tensioner systems.

    The system can be installed, calibrated and commissioned in one week while the vessel is in operation. The calibration and fine-tuning after installation requires movement of the piston. The normal procedure requires a trial with full motion for calibration, an hour for analysis of data, and a final verification run.

    Graphical user interface

    The PistonTrack® graphical display has been designed to give the driller a clear and intuitive graphical picture of the accumulator position and movement, thus allowing operation of the rig within safe limits.

    PistonTrack® can be accessed remotely from shore, allowing adjustments and monitoring in response to the request of rig personnel.


    Pistontrack is currently installed and in service on the following semisubmersible drilling rigs and ships:

    • Bideford Dolphin
    • Snorre B
    • Borgland Dolphin
    • West Navigator (main rig)
    • West Navigator (aux rig)
    • West Venture (main rig)
    • West Venture (aux rig)

    Technical Specification

    PistonTrack is based on a proprietary electromagnetic method. The system works by monitoring the piston from an array of individual sensor elements clamped to the outside of the accumulator. PistonTrack is reliant on mounting a permanent magnet on to the piston before operations.

    Sensorbar with 3 sensing elements

    Length x width x height: 1000 x 67 x 37 mm
    Material: PE80, antistatic polyethylene
    Max. cable length to EX cabinet: 15 m (50 ft)
    EX protection class: EX-m (molded polyurethane)
    Ex housing near accumulator
    Material: AISI 316 (stainless steel)
    EX protection class: EX-d, IP- 68 – Up to 4 sensor bars per EX housing

    Power supplies:

    – Datalogger: 24 V DC, 5A
    – Measurement system: 24 V DC, 20A Data logger and operator display

    Industrial PC with PistonTrack® software and graphical display Remote support, upgrade and maintenance

    Online connection via local area network Optional 4-20 mA analog output

    Data communication

    Simplex RS485 with signal ground

    Power consumption

    Data logger and display: 25 W (typical)
    Sensors and electronics: approximately 7 W per primary sensor


RiserMonit® System

RiserMonit® Carcass Detector

The RiserMonit® Carcass Detector is designed to detect a potential failure mode in flexible risers where the carcass may be overloaded close to the end termination. The tool is installed on the platforms in the North Sea. The detector is among the world’s first tools to be installed inside a producing riser. The RiserMonit® Carcass Detector applies the Sensorlink ultrasound technology to detect the possible carcass failure applying an internally mounted UT reflector. The RiserMonit® Carcass Detector holds Ex certificate for Zone 1. The carcass position status is communicated to the control system and to local indication panels.


    RiserMonit® Vibration Monitor

    This product is used to ensure that vibration levels on offshore installations are kept within safe operating limits. Real-time vibration information i automatically transmitted by the RiserMonit® monitor to the main data acquisition system onshore. Currently the monitor is installed on the Gjøa platform in the North Sea to measure vibration levels at selected locations on the export riser base. The sensors are installed on steelwork on the ERB, and are connected to the data acquisition system by electric jumper cables. The RiserMonit® Vibration Monitor is developed in close collaboration with GdF Suez.

    RiserMonit® Motion Monitor

    This is a concept based on the technology from PipeMonit® and the inclination sensor used there. The autonomous belts from Sensorlink can be used for measuring the inclination and motion of any object, including risers and derricks. The RiserMonit® Motion Monitor is delivered as customized project and the form factor is adapted to the customer’s needs.


Data presentation

All functions required to operate the transducers, including data processing, are actioned through SAM (Sensor Array Module) electronic cards. The ultrasonic transducers and their associated electronics are installed in polymer cassettes. A number of these cassettes are installed in the UltraMonit® monitoring clamp which is connected to a data logger.

Measurements collected from the data-logger are stored on a data server. Monitoring data are made available to the end user via a WEB based graphical user interface. This interface allows for quick evaluation of corrosion status by traffic light colour logic.

The end user can study the raw data from each transducer, or apply filters to enable a quick view of any transducer that has detected a corrosion or erosion rate greater than a predefined value set by the user.

Special projects

Sensorlink has years of experience applying different technologies for monitoring pipes and steel structures.

RiserMonit® is a tailored range of products and concepts for advanced riser integrity monitoring. The RiserMonit® systems are primarily based on ultrasound or electromagnetic sensing technologies.

The products and concepts are developed through customized projects. Sensorlink develops solutions in close collaboration with its customers according their immediate needs.