Tug and offshore vessel operators can extend the lifecycle of thrusters using Wärtsilä’s condition monitoring services
Condition monitoring can extend the life of thrusters and reduce the risk of failures, which is vital for operators and managers of tugs and offshore vessels. Analysis of performance data enables engineers to identify condition issues, predict the timing of failures and extend the period between overhauls.
This lowers operating costs for owners and reduces the amount of drydocking visits for workboats and vessels, explained Wärtsilä’s manager of the condition-based monitoring CBM Centre Propulsion, Stefan van Loenhout.
Wärtsilä secured its first customer for an advanced performance-based service agreement when it signed a deal with drilling rig and ship operator Transocean, announced in July. Together they intend to optimise the maintenance of Wärtsilä thrusters installed within Transocean’s fleet of deepwater drilling systems, using Wärtsilä propulsion condition monitoring service (PCMS), which collects performance data from the thrusters and delivers it to Wärtsilä’s CBM Centre for analysis.
Mr van Loenhout thinks this type of agreement can be used by owners of tugs and offshore support vessels to improve the reliability of thrusters. PCMS provides “real-time advice and periodic reports concerning the condition of the machinery” he told Tug Technology & Business. This leads to “more availability than could be realised through conventional planned maintenance.”
Through condition monitoring, owners can base their “operational decisions on the actual condition of the equipment and assess risks based on the projected reliability of the propulsion equipment.”
Vessel operators can perform overhauls only when they are actually needed instead of doing them periodically. Mr van Loenhout said owners can extend the time between thruster overhauls from five years “to a maximum of 10 years, based upon the actual status of the thrusters.”
This is because tug operators would be informed of faults “well before they lead to breakdowns” and “conditions that generate excess wear on the equipment can be avoided.”
“Condition monitoring reduces the total cost of ownership and maximises profitability throughput the lifecycle of the vessel”
“As a result of all this, a condition-monitoring service reduces the total cost of ownership and maximises profitability throughput the lifecycle of the vessel,” said Mr van Loenhout.
These expectations will be tested during the contract with Transocean, which will involve service engineers analysing the data to determine when thrusters will need servicing in a drydock. Engineers will produce flexible maintenance schedules for each piece of equipment based on the actual condition of the device.
Wärtsilä and Transocean expect this will reduce drydocking requirements as they anticipate each thruster will be overhauled just once during the 13-year agreement period. This covers five semi-submersible rigs and one drillship, each of which has six to eight thrusters.
Other engineroom machinery can be monitored in a similar method to thrusters with comparable results, if the needed data is available and accessible. “This reduces the lifecycle costs of equipment and enhances profitability,” said Mr van Loenhout. “And prevents unscheduled events before they happen.”
Wärtsilä’s propulsion condition monitoring service combines sensory data such as vibration, pressure and temperature with the operational parameters of the propulsion equipment, such as pitch, steering feedback and set points.
In addition, it takes into consideration the nautical parameters, such as vessel speed, rate of turn and draught, “thereby giving the customer the unique ability to accurately relate sensory data to the actual operating conditions,” said Mr van Loenhout.
The system has been developed to detect the operational state of the propulsion equipment through real-time comparisons of parameters from multiple sources. Data is captured and sent over the vessel’s satellite communications or links to a 3G or 4G mobile network if close enough to shore.