Condition monitoring of mission critical vessel machinery is rapidly becoming industry standard. Rovsing Dynamics, a MAN Diesel approved condition monitoring supplier, provided a forum for knowledge sharing at the SMM trade fair in Hamburg. The open seminars were titled “Vessel Condition Monitoring for Condition Based Maintenance – What to gain and how to get there.”
Ship owners, who have implemented monitoring solutions together with Rovsing Dynamics, will share their goals and practical experience with monitoring of main engine bearing wear, thrusters and turbochargers. These include PRISCO (tankers), Reederei F. Laiesz (Car carriers) and Scandlines (ferries). DNV, Germanischer Lloyd and Lloyd’s Register will present their guidelines for a successful Condition Based Maintenance strategy, supplemented by the requirements of MAN Diesel, who now recommend ship owners to completely omit regular open-up inspections of the crank-train bearings of certain engine types with an approved bearing wear monitoring system, among other things.
Ship owners monitor critical machinery for various reasons. Most want to avoid damage and save millions on repair costs and off-hire. As one example a ship owner, who monitors main engine and turbochargers, discovered a turbocharger problem in due time to take action, thereby avoiding risk of significant consequential damage. Some also aim to increase vessel availability by omitting costly, time-consuming open-up inspections and only conduct condition based maintenance. Early adopters have moved from test to implementing online monitoring on their new ships as well.
– According to our customers, guidelines and support from classification societies and machinery makers are paramount for a successful implementation of condition monitoring, said Rovsing Dynamics’ CEO Thea Larsen. – But it seems that each classification society create their own guidelines. Recently, one of these suggested that class and machinery suppliers should work together to harmonize specifications for exchange of condition monitoring information to facilitate wider implementation of Condition Based Maintenance. We therefore took the initiative to host a forum at SMM for dialogue between all parties involved.
Last year the company hosted a similar successful event in Athens, where ship owners encouraged the class and engine designers to make condition monitoring mandatory. Today, this seems to be much closer to reality.
Contract with Trico Marine Services
Trico Marine Services Inc., a leading US provider of marine support vessels to the offshore oil and gas industry, is to install advanced online condition monitoring solutions from Rovsing Dynamics on its 8 new multi-purpose vessels (MPVs). The new 2,900 dwt supply vessels will be dedicated to subsea installations for e.g. floating production, storage and offloading vessels (FPSOs).
The versatile OPENpredictor solution will monitor the condition of 4 tunnel thrusters as well as the main reduction gear on all 8 vessels. This can be performed with only one online system per vessel.
Trico Marine´s Trico Sabre
According to Ray J. Hoover, Trico’s Global Director of Technical Services, OPENpredictor was chosen not only due to its ability to automatically detect machinery faults at an early stage, but especially because its early warnings are accompanied by prediction of lead time to inspection. Early warnings about problems will prevent lost revenue from off-hire and increase availability.
– We want to get advance warnings about developing problems in our most business critical, expensive machinery to ensure that we can meet our customers’ requirements, and to avoid losing charter hire due to unscheduled repair, says Ray Hoover. – In the past we have experienced problems with tunnel thrusters. The thrusters and the main reduction gear are crucial for the dynamic positioning of our offshore supply vessel during customers’ subsea operations e.g. when lowering down equipment with a crane. In view of the very long lead times on spare parts, a thruster or gear problem can easily put a vessel out of operation for several months. Beside the immense repair costs and lost hire of several million dollars, we also risk loosing credibility with our customers.
Normally, an off-shore supply vessel goes to dry dock 2-3 times over a 5 year period for planned overhauls. Online condition monitoring enables Trico to pursue a more pro-active, condition based maintenance strategy, and achieve the goal of having the vessels available to clients up to 120 consecutive days. If possible, they would like to reduce dry docking to the class notation – only once every 5 year – thus increasing vessel availability and revenue significantly.
– Condition monitoring and predictive maintenance increase our comfort level as well as vessel reliability and availability. With prior knowledge about deteriorating components we can plan repairs in between charters and reduce the number of off-hire days. And we avoid loosing revenue and enhance the possibility of reaching our target of 90-95% utilisation, Ray Hoover concludes.
– Our cooperation with Trico takes our OPENpredictor monitoring solutions into yet another application area: offshore supply vessels, says Rovsing Dynamics’ CEO Thea Larsen. – This is just another example which demonstrates the value of predictive maintenance information for the optimization of vessel operation and maintenance.
Another OPENpredictor solution for Azimuth thrusters has been operating on a Scandlines ferry for more than a year. Since Rovsing Dynamics began developing solutions for maritime use four years ago, numerous customers have installed stand-alone or combined solutions to monitor diesel engine bearing wear, turbochargers, pumps and thrusters on containerships, tankers, car carriers, multi-purpose vessels and ferries.