GL Exchange Forum on Condition Based Maintenance

In shipping, maintenance costs represent nearly twenty percent of all operational costs. According to independent sources, expenditure on repairs and maintenance has increased lately across all vessel categories. In respect to repairs and maintenance there are significant variations in the cost movements experienced within individual vessel categories.

The latest GL Exchange Forum in Hamburg put this topic on the agenda and invited representatives from ship owners to discuss cost sensitive maintenance strategies. While some voices in the market claim that shipping companies are now more likely to postpone maintenance and the installation of new equipment, which would jeopardise safety and the environment, GL offers a smart “condition-based maintenance” approach (CBM).

GL’s expert on condition monitoring, Jörg Rebel, informed the attendees about GL’s contribution to CBM pilot projects with shipping companies, engine makers and condition monitoring system manufacturers. He explained how GL is ready to support shipping companies in condition-based maintenance by offering the development of tailor-made CBM concepts. GL’s service portfolio contains type approval of condition monitoring systems including field tests for demonstrating the reliability of the condition monitoring information as well as survey arrangement for condition monitoring matching the CBM concept of any individual vessel.

Survey arrangements help the ship managers to avoid unnecessary open-up inspections, e.g. of crank-train bearings. Condition-based monitoring is already in place at German shipping lines Hapag-Lloyd and Peter Döhle Schiffahrts-KG. In addition, engine maker MAN Diesel presented their new approach for condition-based overhaul of crank-train bearings at the GL Exchange Forum. In 2008, MAN Diesel introduced condition-based overhaul for crank-train bearings of MC/MC-C and ME/ME-C type engines. It is now mandatory for all engines on ships ordered after March 1st, 2008. One of the major objectives is to avoid unnecessary open-up inspections with the inherent risk of causing maintenance-induced damage. Visual inspection of i.e. shaft bearings, crankshafts, bedplates and crossheads was traditionally the only way to determine impending problem, but it is limited to only detecting visible faults to a well-trained eye at the time of inspection, and in a worst case scenario can actually create damage.

Jörg Rebel predicts, that in the long run newbuildings will be equipped with integrated machinery monitoring tools to improve maintenance processes. In addition, the increasingly complex machinery and the high levels of monitoring available, are calling for standardised systems in order to streamline monitoring processes on board. Arguments about the financial implications of an investment such as installation and purchase costs of a condition monitoring system are to be countered by taking account of off-hire time of a chartered vessel in case of an unplanned repair stop at a shipyard. GL allows the utilization of approved condition monitoring systems to be used instead of expensive visual inspections. Monitoring systems save time and money and keep multi-million dollar assets running according to schedule as well as reducing maintenance costs.