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.
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.
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).
PistonTrack® can be installed on all types of drilling rigs. It is suitable for new-build or retrofit on existing installations with:
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.
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:
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.
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
– 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
Simplex RS485 with signal ground
Data logger and display: 25 W (typical)
Sensors and electronics: approximately 7 W per primary sensor
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.