Condition Monitoring the Key to Ship Automation – Wärtsilä
In its drive to be a total systems supplier to the maritime industry, Wärtsilä is looking far beyond its core propulsion-related product portfolio
In a recent article Mirja-Maija Santala, Media Manager, Wärtsilä Corporation explains how a combination of factors is leading to a higher level of automation across all ship systems.
Modern ships have many systems – in addition to those controlling the machinery there are cargo systems, communication systems, voyage planning and navigation – the list goes on. At the same time, this complexity of ship systems is countered by desires to cut costs and reduce manning levels, without compromising efficiency or safety.
All of these pointers lead to one thing – a higher level of automation, across all ship systems. Wärtsilä has built a strong foundation for this in its application of Condition Monitoring (CM) and Condition Based Maintenance (CBM) systems for its engines. “Condition based maintenance is about knowledge of the particular installation, with maintenance decisions based on real-time monitoring. This means maintenance planning and actions being taken accordingly, thus avoiding unscheduled downtime,” says Jens Vägar, Manager CBM at Wärtsilä’s Technical Services in Vaasa, Finland. “In short, condition monitoring and condition based maintenance help optimise performance.”
Mr Vägar describes CBM as being first and foremost a thorough understanding of the process coupled with the input of relevant data, which enables predictions to be made based on analysis and trends. These predictions, in turn, lead to the formulation of plans and schedules for maintenance, with cost predictions. Such plans are dynamic rather than governed by pre-determined schedules, allowing maintenance to be performed when it is actually needed, rather then ‘just in case’, and coordinated with the ship’s operational schedule. The final element is a follow-up to confirm that the maintenance has been successful.
Keeping track of trends and developments
Wärtsilä has three CBM centres; Vaasa, looking after four-stroke engines in both marine and power plant applications; Winterthur in Switzerland for two-strokes, and the CBM Centre Propulsion in the Netherlands. Information from the sensors is sent to the centres at regular intervals, and compared with the data held on file for that installation. Wärtsilä engineers determine the ‘normal’ levels after taking into account the particularities of the individual installation and the expected conditions. Should any parameter extend beyond the normal range, or if a trend is noted that indicates a problem may be developing, this is noted, and the engineer determines whether action may be needed.
At agreed intervals, generally monthly, Wärtsilä sends a report to the customer, with any deviations from normal highlighted by a ‘traffic light’ system, where green signifies that all is OK, yellow shows that caution may be needed but there is no immediate risk of failure, and red indicates that maintenance action needs to be carried out or planned for the near future. The report will include the engineers’ recommendations. Interim reports will be sent if a critical point is noticed.
Service agreements for all situations
The exact level of attention that the customer can expect depends on the type of service agreement in force.
Wärtsilä operates four levels of service: • parts supply, with fitting by Wärtsilä service personnel if required; • technical management, which covers inspections, expert assistance and monthly reporting, exchange programme planning, and which can also include online condition monitoring, maintenance planning and full technical support and training; • maintenance agreement with the customer’s own operating personnel backed by planned maintenance, including service crews from the Wärtsilä global network where and when needed.
This level of service is generally provided on a fixed price basis, with performance guarantees. • asset management, which is a comprehensive operation and maintenance agreement, tailored to individual customer requirements, but generally covering full operation, management and maintenance services, again with performance guarantees.
Wärtsilä has considerable experience in long term service agreement based on the CBM concept, with some 400 installations and 1,700 engines. The latest agreements also include thrusters. The company’s first marine application was in 2002, for a Dutch dredger, and since then agreements have been implemented for a broad variety of vessels, mainly in the offshore and cruise sectors, but also general cargo and other ship types. The first marine installation to have a permanent 24/7 online connection to the Wärtsilä service centre was in 2007, on a drill ship operating in the North Sea oilfield.
The company has seen a steady increase in the number of CBM installations. Up to now, most have been in land-based power plants. However, the number of marine installations is also on the increase. With the growth of affordable satellite communication data links, about 70 per cent of the marine installations can now be offered the use of an online connection, whereas earlier it was only about 30 per cent.
Although CBM itself is an established concept to avoid unplanned downtime, with some 90 per cent accuracy, and increased availability and reliability, Wärtsilä sees its enhanced version of the system as a way of helping ship operators optimise performance and reduce costs still further. “Improvements in fuel consumption of up to 5 per cent are perfectly achievable through using CBM to optimise the running of a propulsion plant,” says Mr Vägar. “This is on top of the well-known benefit of reduced maintenance costs, which is up to 20 per cent with our system.”
The system makes it possible to optimise ship propulsion plant operation, making use of mathematical models for calculating the ideal operating parameters, and to dynamically compare actual with optimum values. The system takes into account variables, such as ambient conditions, as well as installation-specific data including the engine specification, installation type and configuration, and design criteria. As well as optimising fuel consumption, it can be configured to reduce harmful exhaust emissions. Using measured values of parameters, such as fuel pressure, charge air pressure and bearing temperatures, the engine’s operation can be optimised and a maintenance plan drawn up. “CBM allows maintenance functions to be scheduled together; not all scheduled intervals, based on actual hours of operation, can coincide exactly,” says Mr Vägar.
Wärtsilä Optimisers – a ‘Next Generation’ Platform
Thus, the existing CBM system provides a basis for a more comprehensive, and more integrated, way of monitoring the operation of the whole ship. Wärtsilä describes this as the ‘Optimisers’ concept. The concept provides a platform to add different equipment, and to link, through any type of communication link, to any application located anywhere. The monitoring provided at Wärtsilä’s CBM centres can, therefore, be used in conjunction with the owners’ and operators’ own office-based systems, as well as third-party tools like turbocharger analysis systems. “Instead of having 10 different monitoring systems, we need just one to monitor everything,” Mr Vägar explains.
One very important consideration in such an approach is security of data. Easy optimisation and maintenance of the software is essential, with no risk of obsolescence.
Mr Vägar explains that another key issue is getting different types of systems, from different manufacturers, to communicate. He is confident that Wärtsilä can develop a suitable communication protocol that can be used by its partners; a major step in this direction has been achieved with the Wärtsilä 3C control system. This is described as “the first such system to fully integrate all significant data into a single platform to support decision making”.
The Wärtsilä 3C is at present a shipboard system rather than one intended for data exchange between ship and shore, but it should provide a platform suitable for expansion into remote operation. As a system designed for “fluent control of the vessel with priority given to situational awareness, safety, ergonomics and efficiency, which acts as a key enabler for the leveraging of energy management and integrated navigational solutions into a single powerful tool”, it goes a long way towards realising the company’s expectations regarding Optimisers. With 3C, advanced route planning is enabled through online data processing between the various systems, including ECDIS, voyage optimiser, econometer, power management, automation, weather chart, Navtex, and dynamic hull data.
The Optimisers system collects data on site, stores and analyses this data according to pre-set rules, and sends the data to Wärtsilä for more detailed analysis and a complete report. The on-site system provides simple reports and trending information to assist with instant decision-making, and users will have access to the Wärtsilä portal to access the detailed information and to obtain assistance.
The principle – any data, anywhere – rather accurately describes the approach. Optimisers provides a more holistic approach to asset analysis, as it combines not just engine data, but also all relevant information concerning the operating environment and developments that could significantly impact the lifecycle and fuel consumption of the installation.
The on-site platform can be likened to a hub for information through which different services, such as PCMS, can transmit data to Wärtsilä’s CBM centres. The central side not only provide Wärtsilä experts with access to the data, but also enables the customer to obtain relevant data via the Wärtsilä portal.