Awilco WilHunter Semi-Submersible Rig
1: Fire Damper Monitoring: Critical Safety System
Monitor Systems were approached by Awilco Drilling PLC to look at the design and manufacture of a Fire Damper Monitoring System for the Semi-submersible Rig, Awilco Wilhunter.
Our fire damper monitoring system provides accurate, continuous real time monitoring of the status of all critical fire dampers installed on the rig.
SYSTEM: Working closely with rig managers and operators, Monitor Systems allowed for a Fire Damper Monitoring System with the capability of monitoring a total of 24 dampers, plus a 20% spare capacity for system expansion if required in the future. The system hardware was based around all fire dampers being monitored in both the open and closed position with intrinsically safe circuits built in for added protection and accurate monitoring.
The 15” HMI screen provides indication of the fire damper status; red for open and green for closed. The HMI screen has a mimic plan overview of the rig with the damper indication shown. An alarm sounder was built into the system, activated immediately when any of the fire dampers opens. The HMI screen was provided with a wall mounting bracket so that it can be mounted in a suitable location within the control or radio room of the rig.
PREVENTION: The monitoring of fire damper status is essential for vessel operators in preventing fires and gases from spreading and in particular important in the protection of safe refuge areas during emergencies.
2: Tank Gauging Sensors
Monitor Systems were approached by Awilco Drilling to design, deliver and commission a Tank Gauging System for the WilHunter Semi-submersible. This project involved everything from management, system design, schematics, factory acceptance test and the commissioning of all tank gauging sensors.
Tank gauging sensors are an integral part of the tank gauging systems installed on many offshore rigs including semi-submersible rigs, jack up rigs, supply vessels, ships and barges. The sensors selected have a wide range of applications and better versatility than most other tank level gauging sensors. The sensor is also accurate and reliable with problematic, corrosive, acid or foaming fluids, low viscosity fluids, suspended solids, variable specific gravity and temperature variations, as it is with standard liquids.
Custom Design Solution: Monitor Systems were able to custom design a solution for the rig based on ‘Bubbler’ depth sensing technology tank level sensors. All 35 sensors were sited directly outside the Control Room. This minimised installation logistics allowing existing pipe-work to be utilised and thereby reducing overall installation costs.
Engineered: The tank gauging systems are engineered to meet the demands of offshore applications and environments by incorporating computer technology with state of the art features into a microprocessor based tank level indicator. The sensor combines automatic leak and plugged line detection with automatic “hardware zero” that compensates for pressure differentials. If an abnormal condition is detected, the sensor will display the appropriate error message on the digital display and/or provide the data on the communication bus to alert the operator.
3: Fire and Flood Monitoring System for Cold Stacked Rig
The Awilco Wilhunter is currently located (April 2017) in the Cromarty Firth near Invergordon. The vessel will be “cold stacked” in this location for an undetermined amount of time.
SCOPE: As the semi-submersible is unmanned during the cold stacking period, it will be necessary to monitor the rig for certain alarm conditions including fire detection and flood detection. Monitor Systems were asked by Awilco Drilling PLC to bring forward a solution for the monitoring of fire and flooding whilst cold stacked.
Fire detectors were installed in key locations around the vessel and submerged areas containing vital services, i.e. the pump / thruster rooms were monitored for flooding. The Fire and Flood Monitoring System is powered by a solar array with battery back-up, and the battery and power supply is also monitored for (low state) alarm conditions.
The new Fire and Flood Monitoring System installed alert both Awilco and Monitor Systems personnel by sending out an alarm e-mail should any alarms be activated. A VPN connection allows the client to login to the system remotely and view the system status.
CASE STUDIES: For an overview of some of the varied work undertaken for the Awilco Wilhunter Semi-Submersible Rig, please read our case studies page.