Performance monitoring rapidly becomes a total solution

29 Feb 2012
Information is captured as part of the crew’s normal daily routine, says Datatrac

Information is captured as part of the crew’s normal daily routine, says Datatrac

Just a few years ago, real-time system monitoring was only used by a few, technically advanced ship operators but, increasingly, intelligent data management systems are rapidly turning it into a practical and accessible tool for compliance and performance monitoring, writes Wendy Laursen.

Increasingly sophisticated machinery control and condition based maintenance systems are expanding engine monitoring into whole-of-ship and whole-of-fleet monitoring as intelligent data management expands to include voyage, energy use and emissions data. Add propeller performance and navigational data to equipment data and you have voyage management for improved fuel management and route planning. Add electricity, waste generation and stack monitoring data and you have an environmental footprint.

“Since all of that data can be collected and sent via satellite to web-based systems, it means that both original equipment manufacturers and operators can analyse it on a real-time basis from shore no matter where the ships are,” says Dr Dale Neef, managing director of independent data management consulting company DNA Maritime in the US. “To make sense of it all you also need some good business intelligence software so we are now beginning to see software systems emerging that can organise and analyse that myriad of data and present it through dashboards, scenario planning tools and drill-down diagnostics.

“Eventually, I believe the large fleet management software providers will try to provide this advanced information analysis as part of their software in a more fully integrated way with separate modules for maintenance, emissions, ballast, fuel efficiency etc, all sharing relevant electronically collected data.”

The increasing use of intelligence software is a double-edged sword for crews, says David Chaters, technical manager at Meridian Marine Management in the UK. While they can release ship staff from the soul destroying task of producing several similar reports for different end users, it can also rob them of their normal critical thought processes. Less traditional monitoring and maintenance can be done by ship’s staff. “Unless you have the control software, normally firmly in the control of the maker, it is difficult to fault find never mind repair some equipment,” he says.

“There should be an understanding that the shore-based office does not manage the ship whilst those on board run it. We are all in this together. The management team runs from the ship to the office and the use of intelligent software should enhance this. The major change to what those on board do will not be the use of modern software systems (they tend to have training and affinity to IT-based solutions) but to how this will change and empower their positions in the management team,” says Mr Chaters.

US-based Intellocorp claims their data analysis software will improve decision making and increase transparency in ship operational performance. Intellocorp’s ShipStrument Dashboard software provides ship operators with over 600 vessel and fleet-wide performance indicators. The company has now launched ShipStrument v2.06 which offers integration with ship management systems such as Amos-D, Imos, NS-5 and Napa. Intellocorp is able to automate 85 per cent of the data loads.

Thinking of recent accidents such as the grounding of the Rena off New Zealand, John Walton, installation engineer for Datatrac, says that the systems his company provides for data collection and analysis can help companies charged with a violation demonstrate that they are taking steps to ensure company procedures are now being followed.

One of Datatrac’s products, Envirotrac, allows efficient monitoring, recording and audit of systems such as oily water separators. Electronic tags are fitted to the equipment, pipe work and associated valves and flanges to record any unauthorised bypassing of the system. Datatrac’s scope of delivery also includes customised data analysis and reporting systems, including a web-based interface.

Earlier this year, Overseas Shipholding Group (OSG) renewed its contract with Datatrac for a further three years. OSG already has Datatrac systems on over 65 of their tankers so OSG fleet managers have immediate access to vessel operational data and are able to make decisions based on detailed historical and comparative trends. The information is captured as part of the crew’s normal daily routine and it takes less time to collect and log data than manual systems, says Datatrac.

TESTING INACCESSIBLE SYSTEMS

The installation of online systems on ships is only justifiable for certain machines or areas, says Johann Lösl, managing director of Prüftechnik Condition Monitoring in Germany. These include drive trains, inaccessible thrusters and important auxiliary units such as engine room fan, main generator, turbocharger and fuel centrifuges. In certain types of ships such as cruise ships or car carriers, online monitoring of inaccessible ventilation systems is also highly recommended.

Although online monitoring can be easily integrated into the ship information system, machine condition data are typically measured manually every six to eight weeks. “Getting reproducible results with offline measurement systems is a challenge that calls for certain precautions,” says Lösl. “Ideally, the data should always be collected by the same well-trained crew members, a policy that will ensure a consistently high quality of data unless special techniques like the Vibcode studs are used. These intelligent measurement studs will allow reliable collection of data even when only little training can be given, which is typically the case onboard ships.” Incorrect measurements can occur when they are taken at the wrong location, in the wrong direction or if sensors make poor contact. “Compared to a normal magnet mount, Vibcode addresses these issues in an ideal way,” says Lösl.

Generally, characteristic overall values for the machine vibrations (e.g. according to ISO 10816-3) and roller bearing condition are recorded for trend analysis. More in-depth machine diagnosis requires additional signal measurements like spectra. For reasons of crew capabilities and capacities, the data is almost never evaluated onboard, says Lösl. Prüftechnik’s Omnitrend PC software makes it possible to export the data to a file as they are being read out of the data collector and forward them in an email to the operator’s headquarters or diagnostic centre. The database on the ship is thus a copy or subset of the main data base on land. In return, changes to the measurement parameters can also be made via a file. As the data quantities are small, transmission costs are low.

Schaeffler Group has introduced a system designed to make real time monitoring cost effective for small or redundant machinery such as electric motors, pumps, compressors, ventilators, fans and gearboxes. The FAG SmartCheck comes with a set of parameters that permit a reliable general monitoring of machines plus over 20 predefined parameter templates for monitoring imbalance, alignment errors, rolling bearings and fans. The system’s alarm thresholds are adjusted automatically due to a patented self-learning mode and after commissioning, the FAG SmartCheck works autonomously. The relevant machine parameters are recorded and can be accessed via a standard Internet browser.

Original equipment manufacturers are moving increasingly towards sophisticated control products. MAN Diesel is rapidly expanding its electronics and software development capabilities and senior manager Henrik Rechnagel Olesen expects the rate at which innovations are brought to market to increase with new technology introduced at the company’s testing facilities in Copenhagen. A more sophisticated in-house testing system reduces the manual effort involved in testing new equipment and provides more sophisticated accelerated lifetime testing.

One recent development is an add-on to MAN’s ME engine range that enables switching to LNG combustion initially targeted at LNG carriers that can use boil off gas without the need for onboard re-liquefaction. New hardware and software provides the gas monitoring and safety functionality required but the equipment is easily retro-fittable to existing engines. Taking a whole-of-system approach, the system also controls supporting equipment including seal oil pressure and inert gas in a redundant, failsafe arrangement that can switch seamlessly between fuel types if required.

MAN Diesel’s cylinder controller is currently undergoing redevelopment to produce a smaller, more robust unit that has better vibration and temperature performance. Even though the unit is in a simpler cabinet, the effects of electromagnetic interference have been reduced. The improved accelerated lifetime testing enabled rapid design of the new unit which will reduce engine manufacturing costs.

Another cost saving achieved is a move away from standard marine PCs as user interface to their engines. A stripped down PC with a solid state disc rather than a hard disk, and no extras or cooling fans, is expected to double the lifetime of the PC.

IMES of Germany is developing technology for engine builders. Hyundai Heavy Industries of Korea is to supply the IMES EPM-XP device for periodic monitoring of cylinder pressure with the two-stroke MAN B&W MC/MC-C and Wärtsilä RT-flex diesels it builds and sells under license. Ship operators can be increasingly confident that engines in the field are set-up according to their guidelines and will thus run more economically and more reliably, says IMES.

ACOUSTIC EMISSIONS WARN OF IMPENDING CRACKS

Vibration analysis has provided a trusted approach to condition monitoring for the past thirty years but it remains a complex science and requires sophisticated knowledge and understanding from a seasoned expert, says Martin Lucas, managing director of Kittiwake. In contrast, acoustic emissions (AE) technology extends and simplifies the science.

AE technology is based on frequencies much higher than are monitored in the repetitive synchronous movement of vibration. They are the result of shock, impact, friction and cracking and make it possible to detect impending failure and monitor its progress.

Signals in the 100kHz range for bearings and the 40kHz range for air leak detection are presented in an easily understandable, numerical form by the AE sensor developed by Kittiwake Holroyd. “Ultimately, maintenance personnel are responsible for keeping machinery running. If they are empowered to monitor condition themselves, identify where action is needed and then check that the action taken has solved the problem, then AE has significant advantages of cost, speed, flexibility and ease of field application,” says Lucas.

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