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The repair and maintenance of naval vessels deployed away from their primary support infrastructure is an often overlooked area with existing repair and maintenance ships either being of old design or vessels converted from commercial ships. Increasingly the nature of the Royal Navy and other navy operations will see an emphasis on deployments away from home waters for extended periods as global presence is demanded from a decreasing pool of warships. Hence the maintenance and repair of deployed naval vessels will become a significant issue. Additionally future changes in the operating nature of the fleet with an increased focus in support of expeditionary warfare and humanitarian relief operations will require more utilitarian vessels. The impact of these evolving operations on potential concepts for future maintenance vessels has been explored and notional requirements developed. thse have been considered against a variety of vessel options and an innovative heavy lift ship solution has been developed as one potential concept for an expeditionary repair and maintenance platform. This paper explores some of the potential future requirements for the next generation of repair and maintenance vessels within a historical context of current and past vessels. Two case studies are presented and discussed for a cable ship conversion and an innovative heavy lift concept as potential solutions.

Diesel TES Engine Oil has a high-energy efficiency and can therefore help to reduce carbon dioxide emissions and so it is expected that this will be widely adopted. However several issues remain including the bother of engine oil maintenance. The purpose of this research was therefore to lengthen the maintenance interval of the engine oil to 16000 hours. To achieve this longer maintenance interval a special oil was developed that has a synthetic base stock. Simulations of the oil's degradation were carried out and it was succeeded in preventing degradation by developing a system for extracting degraded oil and adding new oil. It was also made possible to monitor degradation of engine oil by installing a soot sensor to measure the concentration of soot which is the factor that has the largest effect on the degradation of diesel engine oil. In addition an electrostatic dust collector was installed to avoid problems caused by soot contamination. This collector worked well when the oil deteriorated. The verification tests of this system showed that the oil's properties stopped changing completely after 1500 hours of operation and operation is now continuing smoothly at the 8000-hour point. However even if the oil maintains its high performance tests of small engines have confirmed that the conditions of the pistons change over time. While engine oil maintenance can be avoided the engine itself must continue to be maintained at regular intervals.

Features of warship design which facilitate easy maintenance for seagoing engineers and supporting shore staff are discussed and the principles of designing for maintenance are emphasised through discussions on equipment selection the policy of maintenance by removal for repair or by repair in-situ; designing for adequate spaces; openings hoists etc to make the job of maintenance easier; the particular requirements of oil systems and bilges.

A series of articles presents a review of current underwater maintenance practices and equipment. (1) Lloyd's Register approach to in-water survey and maintenance afloat. (2) Underwater maintenance seeing to it. (3) Underwater maintenance paints. (4) Cathodic protection of ships and offshore structures.

The maintenance plan introduced by Petrobras for its offshore terminals in the Campos and Santos basins is described. The performance of the terminals is defined in two ways: environment rate destruction which is a ratio between produced and spilled oil and working rate which links flowed-off and capacity production. Having noticed production losses in 1993 because of buoy and hose problems a new maintenance programme was introduced. This consisted of periodical inspections of the terminals based on a check list preventative maintenance such as regular substitution of hose lines and programmed maintenance. Emphasis was also given to the acquisition of important spare parts. As a result the working rate has increased while the environment rate destruction has decreased.

Integrated Maintenance (IM) a proven approach to condition-based maintenance (CBM) for medium and slow speed diesel engines is presented. IM combines several traditional diagnostic tools to provide independent confirmation and verification of engine condition. Firstly background information is provided. Next cost optimization and integrated maintenance techniques are each looked at in turn followed by engine signature theory and analysis. Case histories are given. After this periodic versus continuous engine monitoring and programmatic issues are each discussed in turn.

Conf held on 12 Feb 1981 Papers are Condition monitoring - does it work? Maintenance organisation and planning for Elf Aquitaine Norges offshore platforms on the Frigg Field A simplified planned maintenance system Underwater welded repairs to offshore structures General maintenance contractors - can they contribute to improve present techniques? The application of non ferrous alloys in offshore maintenance and construction The Department of Energy funded research on repair of offshore structures

Traditional methods of managing warship maintenance are outlined and compared with the concepts principles and practices of modern ship structural maintenance management systems particularly RAMS (Reliability Availability Maintainability and Supportability) RCM (Reliability Centered Maintenance) and RM (Risk Management). The Ship Structural Integrity Program (SSIP) developed for the specific needs of the Canadian Navy and incorporating features of RAMS RCM and RM is described with details of the methodology and its implementation.

Maintenance monitoring is one of the most effective methods to prevent system failure. Ideas on maintenance methods are summarised. Then the fault diagnosis success ratio is discussed and how it affects CM. Next new theoretical results are introduced to evaluate CM and PM. After this the characteristics of these results are investigated in detail and are found to be almost identical to previous experiments on maintenance techniques.

Semn held in Hamburg April 18 - 21 1978 Papers are The European ship repai r industry - current status and future prospects Ship operators view of repair facility requirements Hull loss prevention and mitigation Technology and ship operation En voyage repair and retrofits - the operators viewpoint Progress in classification society survey techniques Corrosion control Retrofitting vessels to comply with inevitable legislation Assessing and planning for drydocking requirements of a mixed tonnage fleet In water survey and afloat maintenance from the operators point of view In water maintenance - a classification society view point In water surveys maintenance and repair - the state of the art Application of low quality fuels in large bore diesel engines Aspects for future bunker fuels and their influence on engine performance Lubrication efficiency as means of reducing operation and maintenance cost Microbial infection of ships lubricants Control systems - availability maintenance and repair Monitoring and diagnostic system for four stroke diesel engines A look ahead in turbine maintenance Marine fuels and lubricants - towards 1990 Spares selection and procurement viewpoint from a ship operator Spares selection and procurement - viewpoint from original spares suppliers - viewpoint from "open market" spares supplier

Semn held in Hamburg April 18 - 21 1978 Papers are The European ship repai r industry - current status and future prospects Ship operators view of repair facility requirements Hull loss prevention and mitigation Technology and ship operation En voyage repair and retrofits - the operators viewpoint Progress in classification society survey techniques Corrosion control Retrofitting vessels to comply with inevitable legislation Assessing and planning for drydocking requirements of a mixed tonnage fleet In water survey and afloat maintenance from the operators point of view In water maintenance - a classification society view point In water surveys maintenance and repair - the state of the art Application of low quality fuels in large bore diesel engines Aspects for future bunker fuels and their influence on engine performance Lubrication efficiency as means of reducing operation and maintenance cost Microbial infection of ships lubricants Control systems - availability maintenance and repair Monitoring and diagnostic system for four stroke diesel engines A look ahead in turbine maintenance Marine fuels and lubricants - towards 1990 Spares selection and procurement viewpoint from a ship operator Spares selection and procurement - viewpoint from original spares suppliers - viewpoint from "open market" spares supplier

Stena Sealink selected Kockumation's MASP system to manage maintenance and spare parts. This decentralised computer system provides information about what maintenance is required and spare part stock information. Management ashore can retrieve or add to the information via satellite modem VHF or land-based telephone from ship to shore.

Today for any large sea-going vessel sailing for example continuously around the world availability and reliability is absolutely necessary. Emerging failures must be recognised as early as possible and this is a strong motivation for a shipping company to invest in condition monitoring. After installation of a CondMon tool the maintenance strategy has to be changed from time-based maintenance to CBM (condition-based maintenance) with the main aim of avoiding unnecessary open-up inspections which might risk introducing failures into a well-functioning system. Further disturbance from unplanned maintenance should also be avoided. The benefit can be only achieved if the responsible classification society adapts its survey procedure to this maintenance concept. Since 2005 the main engine of CV NORASIA ALYA (7 K 80 MC-C) has been equipped with a bearing wear CondMon device and with tools to monitor the load balance between the cylinders and to assess the condition of piston rings and liners.

Various studies regarding reliability engineering minimising risk and minimising maintenance costs have been researched in the past. However until now reliability engineering has remained a challenge. One of the sub-topics related to reliability engineering is risk analysis and maintenance management. The main aim here is to establish a method for creating an optimum maintenance schedule by analysing possible risks maintenance cost and other associated costs. In this research decision-making criterion uses LCC (life cycle cost). Several steps in assigning maintenance schedule are proposed by predicting the appropriate time of those activities based on system reliability and LCC. The steps include determining component functions generating the time predicted and possible component combinations analysing alternatives and uncertainties associated and finally selecting the best alternative using a criterion LCC.

Second Int Conf held in London 5 - 6 Sept 1985 Papers are The international ship repair industry - current structure capacity developments and market prospects The performance of ship repairers - a shipowners views on the inter relationships required to sustain commercial effectiveness necessary for survival Planning modernising and managing a repair yard Manning and operating an independent repair yard to meet shipowners requirements in difficult market conditions Preventative maintenance systems for seagoing ships in worldwide service - an enginebuilders ship to shore performance data and spares/maintenance scheduling scheme Computer based spares/maintenance management systems tailored for the ship operator In situ engine repair developments and the mobile shipyard concept A new technological approach to shiprepairs and services using highly automated drydock facilities The large repair group - challenges solutions and opportunities in a competitive climate Survey developments and the repairer Hull coatings - application and maintenance for improved performance Diesel engine component renovation - developments in techniques and materials/the independent supplier of spares and services Maintenance management by computer

Paper entitled: 'Efficient running and maintenance of automated ships - qualifications of the marine engineer'. Presented at the fourth symposium of the Arab branch The Institute of Marine Engineers, on 'Operation, maintenance, repair of marine equipments and shipbuilding', December 1978.

Recent events have focused the attention of the public on safety at sea and there has been some criticism of ship design detail the use of poor quality materials poor build quality and inadequate inspections of British built bulk carriers in particular. This paper explains how the commercial aircraft industry has progressively improved its structural designs and improved the reliability of its equipment through the use of techniques such as Reliability-Centred Maintenance (RCM). The particular benefits of RCM are that it produces a preventive maintenance plan optimised against failure risk to reduce unplanned failures improves the availability of equipment and reduces costs by better targeted inspections. The use of a fully justified and auditable preventive maintenance plan permits easier safety certification and improves decision making through better identification of risks. RCM is now commonly used in other industries and is being introduced into warship practice in the UK.

Among the many ocean energy technologies under development the tidal turbine farm has been proposed as an environmentally friendly ocean energy converter application. Although the technology and capital costs of ocean energy turbines are understood the economics of operating a gang of turbines as an energy farm has yet to be analyzed. In this paper a planning operation and maintenance model for tidal turbine farms is proposed. The system is modeled using life-cycle assessment incorporating a variety of time-dependent variables. Model components include farm construction and planning operation strategy regular maintenance and emergency maintenance. Preliminary numerical simulation results are shown in a case study for a potential site.

The development of a MMIS (maintenance management information system) for a selected fleet of patrol vessels is presented. The need of automating marine data collection and transmission to the MSRB and the Government Dockyard for maintenance analysis is discussed. Next how the failure and repair data can be modelled by means of the Weibul Distribution is shown together with an objective method for determining the model parameters. Finally with the recent advances in VPN WAN technologies the feasibility of putting the maintenance management information system on the public internet is confirmed.

Hydraulic systems are extensively used in nearly all branches of industry and it is vital that maintenance and efficiency of operating systems are kept at an optimum level. The book starts with a simple account of the basic types of pumps and valves, followed by an analysis and description of systems and circuits. Installation, maintenance, adjustments and operating procedures are given with sections on seals and pipe couplings, system cleansing, valves adjustment and replacement, fault finding, accumulator charging and heat disposal. It is the purpose of the book to deal with the maintenance of the complete hydraulic system rather than individual components.