Lloyd’s Register was founded in London in 1760 to examine merchant ships and ‘classify’ them according to their condition. In the 1990s Lloyd’s Register brought its expertise to bear on other industries, in particular the energy sector.
It also widened its services to include management systems certification. In recent years the Lloyd’s Register Group has expanded its services to the wider transport industry, beginning with rail. Lloyd’s Register develops products and services through three business streams: Marine, Energy and Transportation, and Management Systems – Lloyd’s Register Quality Assurance (LRQA).
These products and services reach clients worldwide through a network of agencies, including Lloyd’s Register Asia, Lloyd’s Register EMEA (Europe the Middle East and Africa), Lloyd’s Register North America and Lloyd’s Register Central and South America.
The Lloyd’s Register Group has over 200 offices worldwide, served by some 5,000 employees. Lloyd’s Register operates independently of any government or other body and can assure absolute commercial impartiality.
A General Committee, comprising representatives of the main industry sectors that Lloyd’s Register works for, oversees the organization.
A significant amount of the profit the organization generates is used in the support of the industries they serve. This support can be seen in the funding of research and development and the education and training of those either seeking or furthering a career in these industries. These support activities are separate from the normal course of business within the Lloyd’s Register Group.
The marine business work involves classification, which sets standards of quality and reliability that must be maintained if a ship is to remain in ‘class’.
The ship’s hull and machinery must meet the requirements of the Rules, and Lloyd’s Register carries out periodic surveys throughout the life of a ship to help ensure this.
The Rules for ship construction and maintenance are constantly revised and updated in line with changes and developments in shipbuilding and current research. The Lloyd’s Register Group also carries out statutory inspections in conformity with international conventions for various national administrations.
A large proportion of the marine business concerns tankers and bulk carriers, but the Lloyd’s Register Group is also a world leader in some of the most technologically advanced vessels: cruise and ro/ro ships, LNG (liquefied natural gas) carriers and naval vessels.
Beyond classification and statutory activities, the Lloyd’s Register Group helps ship operators understand risks and reduce business losses through a number of services such as:
(a) Shore-based technical emergency support, available 24 hours a day, for ships in the event of a casualty.
(b) Fuels and lubricant analysis and advice to help manage the risks of using below-specification products.
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(c) Technical investigation services which can quickly find the causes of problems and minimize losses due to unscheduled maintenance.
(d) A comprehensive environmental protection analysis package.
The Lloyd’s Register Group’s information service provides answers to shipping enquiries and a historical research service. Also, Lloyd’s Register–
Fairplay (a joint venture between Lloyd’s Register and Fairplay Publications) is the world’s largest independent supplier of maritime data.
The Lloyd’s Register Group provides independent risk management solutions that add value in various industry and service sectors: oil and gas;
road and rail; utilities; general engineering and manufacturing; and insurance and project finance.
A wide range of independent verification, certification and advisory services is available to meet client needs at any stage of a project, process or asset life cycle – from feasibility to decommissioning – including:
(a) independent monitoring, evaluation and verification of major capital projects;
(b) verification of asset management systems;
(c) systems and safety engineering, including quantitative and qualitative risk assessment, and preparation and assessment of safety cases;
(d) design appraisal, inspection and certification of pressure vessels and other industrial equipment to recognized codes, standards and regulations including ASME and PED;
(e) RAMS (reliability, availability, maintainability and safety) assessments;
(f) asset integrity services including risk-based inspection, corrosion, engineering, etc.;
(g) global vendor inspection and expediting services;
(h) training and workshops in relation to quality, safety and environmental risk management, asset management and special training programmes on all the services listed above.
The management systems business is provided under the brand Lloyd’s Register Quality Assurance (LRQA). LRQA’s services have grown over recent decades to make it one of the world’s largest international certification bodies. The aim is to provide certification of compliance with international management system standards, thereby helping clients use management systems to reduce risks and improve their business.
The certification market is global and LRQA certificates have been issued in almost every country. Offering a consistent service worldwide enables clients to benefit from Lloyd’s Register’s local knowledge and language capability. LRQA services span a complete range of businesses, from manufacturing, including food, and all transport sectors, to most of the service sectors, including telecommunications, design services, IT, finance and 158 Services of principal shipping organizations
distribution. Assessment criteria cover certification to national, international and industry sector management systems standards in quality, environment and occupational safety management.
Some members of the Lloyd’s Register Group, including LRQA, are
‘notified bodies’ providing services to support EC product directives that ensure consistency of essential product safety requirements across the European Union. This growing activity already encompasses pressure equip-ment, lifts, railway interoperability and medical devices, bringing together the management systems assessment capability and design appraisal available within the Lloyd’s Register Group.
The following section examines two examples or case studies of Lloyd’s Register of Shipping relative to LNG tonnage.
The birth of the large LNG carrier
LNG carriers are now sometimes larger than 200,000 m3. There are several primary technical factors involved in making this capacity feasible. Qatargas’s 209,000 m3 and 216,000 m3LNG carriers from three Korean yards are gas ships that represent a major increase in size. The increasing demand for LNG, especially in the United States and Europe, and the need to reduce long haul transport costs from the Middle East to the United States, is driving this increase in ship size, although it is uncertain whether this trend to ever larger ships for general trades is sustainable, because LNG carriers are restricted by existing port facilities to an upper limit of around 155,000 m3. The bigger sizes are therefore limited to specific projects involving either the construction of new terminals specially designed to handle these carriers or construction of cargo tanks for LNG offshore floating units.
Tank size and configuration
There are several technical factors to be considered during the design, construction and operation of large LNG carriers, primarily determining tank size and configuration and propulsion.
Tank size becomes important when the beam for larger ships increases.
Calculation of overall tank length has to take into account pressure loads from fluid motion in a laden tank.
There are two options for a larger ship – five tanks of conventional size, or four larger tanks. The five-tank configuration is inherently less ‘risky’, as knowledge of the ability of a containment membrane to withstand sloshing loads is based on tanks of conventional size. Furthermore, model testing demonstrates that the highest fluid pressures are associated with diagonal tank motion: lengthening the tank and the diagonal could result in more pressure on the tank membrane.
However, for a number of years shipyards have been investigating tank configuration in anticipation of ordering large LNG carriers. Daewoo Lloyd’s Register of Shipping 159
Shipbuilding & Marine Engineering (DSME), for instance, has carried out a number of studies to validate bigger tanks, including:
(a) LNG tank sloshing studies at MARINTEK in Norway as part of a joint development project with Lloyd’s Register.
(b) Cargo containment system capability testing by dry-drop tests carried out at the Korea Institute of Metals and Machinery.
(c) Dynamic hydro-elasticity properties of cargo containment systems by both numerical analysis and experiments at the University of Illinois in the United States.
New propulsion options
For the larger ship sizes, propulsion is a major issue. The large size of some vessels has led to development of a twin-skeg, twin-screw arrangement as a means of maintaining normal trading speeds. Further, the draught limitation imposed on the new generation of LNG tankers makes it difficult to design an efficient propeller or hull form for a single-screw vessel.
This in turn has prompted the industry to turn away from the traditional steam turbine propulsion utilized by the vast majority of the world’s LNG fleet. The overall complexity and cost of a twin-screw steam turbine arrangement would involve a multi-input gearbox and very large steam-raising plants, making twin-screw steam turbine propulsion cumbersome and expensive. The industry has therefore turned to a number of new propulsion options: (a) dual-fuel diesel electric; (b) twin slow-speed diesel with relique-faction; (c) gas turbine. The Qatargas ships, for instance, use slow-speed diesel propulsion with reliquefaction.
These advances in propulsion have implications for conventional-size ships as well, as all the new options provide the main advantages of a shorter engine room and therefore more cargo carrying capacity. The 155,000 m3 LNG carriers ordered by BP Shipping, for instance, achieved this capacity increase by opting for dual-fuel diesel electric propulsion.
As with any new technology, the risks need to be assessed. Lloyd’s Register, in its work with DSME during the process of the yard’s development of a workable large LNG carrier design, carried out a number of assessments using a typical ‘safety case’ methodology. This method involves two key elements: a hazard identification study (HAZID), which identifies critical issues and looks at engine room arrangements and layout; and a hazard operability study (HAZOP), which looks at detailed piping and instrumentation diagrams from a safety and operability point of view.
Lloyd’s Register Asia’s Busan office facilitated a number of safety cases for DSME, with input from other Lloyd’s Register Group offices around the world. ‘Both types of studies were carried out using a prescribed format of capturing data in a workshop environment with the designers, engine manu -facturers, component suppliers, classification and the intended operator,’ says 160 Services of principal shipping organizations
Thanos Koliopulos, Special Projects Manager for Lloyd’s Register’s Oil and Gas Division. ‘The key benefits of this approach are that it gives the necessary confidence to all parties involved and deals with all the technical issues on the table.’
One of the first HAZIDs Lloyd’s Register Asia carried out for DSME assessed the safety, operability and maintainability of dual-fuel propulsion. A key output of this first HAZID was the adoption of double-wall gas supply pipework instead of the conventional single-wall arrangement. This finding made dual-fuel a more viable arrangement from the safety and operability point of view and enormously improved engine room layout.
Innovations in LNG propulsion
Dual-fuel engines are beginning to make inroads in the LNG sector. The following paragraphs mention some advantages of this system over the traditional steam turbine and also some safety concerns.
Market developments and the introduction of large LNG carriers mean that propulsion is being reassessed. Traditionally, LNG carriers have utilized steam boilers and geared steam turbine plants, but now reciprocating engines are emerging as a viable alternative for the next generation of LNG carriers, for both the new +200,000 m3ships and for conventional-size vessels.
Conventional LNG carrier propulsion plant involves the use of boil-off gas in steam boilers to drive the turbines. The advantages of the steam turbine include its simple energy conversion, high reliability and relatively low maintenance cost. Initial capital investment, however, is high and steam turbines have a relatively low efficiency. As a result, in most marine applica -tions they have been replaced by other means of propulsion, although not in the LNG sector, because until recently there have been no other suitable prime movers capable of using boil-off gases.
Dual-fuel engines
One of these new options is the dual-fuel engine, which is capable of burning both conventional or heavy fuel or oil gas fuel with oil fuel pilot injection. It is capable of operating on either of the two modes when required.
During the gas operation mode, gas is introduced into the engine cylinder either during the air suction cycle at low pressure or injected directly into the cylinder at high pressure during the compression cycle. The gas injection sub-system is normally located directly on the engine and its basic function is to provide timely and accurate delivery of the gas fuel into the cylinder. In the low-pressure system, gas is delivered through an electronically actuated control valve to the engine air inlet ducting. In the high-pressure system, gas is injected directly into the combustion chamber, usually through an electro-hydraulically controlled injection valve.
Dual-fuel has become attractive and viable due to the concurrent development of electronically controlled combustion. The dual-fuel options Lloyd’s Register of Shipping 161
currently being adopted utilize electric power generation to drive electric propulsion systems, such as conventional propellers driven by electric motors.
Diesel electric propulsion systems are considered attractive because they command higher power density than steam turbines and as a result provide more flexibility in terms of machinery arrangements, allowing designers to obtain more overall cargo capacity. The high efficiency of dual-fuel, combined with its low fuel consumption, reduces owners’ and operators’ operating costs and increases their earnings.
Dual-fuel engines incorporating electronically controlled combustion give low Nox and CO2emissions, claimed to be equal or lower than steam turbine plant, potentially making them a more environmentally friendly choice.
An ability of dual-fuel engines to operate on gas or on liquid fuel provides increased operational flexibility and supports the varying demands of ship’s operating schedule.
System safety
The transition of dual-fuel engines into the maritime environment presents a number of design challenges primarily related to aspects of the safe handling of gas in ship spaces. The primary function of these systems is to deliver gas at the required operating pressure prior to its injection into the cylinder.
The low-pressure gas delivery system consists of filters and control valves.
The design of the valve arrangement must ensure that the gas supply can be shut off by predefined abnormalities detected by the engine safety monitoring system and that they can also be shut off manually by the ship’s staff.
The high-pressure gas delivery system is similar, but also contains a compression module consisting of a compressor, pressure vessels and heat exchangers. Gas is compressed to the required pressure and delivered to the common rail system through gas accumulators, thus reducing the risk of pressure cyclic loading on the gas pipes and its connections.
Any leaks from the gas injection system and its associated piping need to be detected and dealt with in a safe manner. ‘Machinery spaces must be monitored by a suitable number of gas detectors and have mechanical ventilation installed to prevent the formation of gas pockets. In practice, constructing a ventilated hood above the engine often fulfils this requirement.’
The safety requirements governing the construction and operation of gas-fuelled propulsion plants are detailed in the International Code for the Construction and Equipment of Ships Carrying Liquefied Gases in Bulk (IGC Code) and the Rules of classification societies.
Lloyd’s Register’s involvement
Since 2000 Lloyd’s Register has provided certification for a number of dual-fuel engine designs intended for offshore and land-based power generation applications. Design approvals in principle for marine applications have been 162 Services of principal shipping organizations
given for both low and high gas pressure dual-fuel systems. Although duel-fuel is now increasing in the LNG sector, already the industry is looking at future propulsion options. In the medium term, gas turbines may become a viable propulsion option for LNG carriers. Gas ships may benefit from the additional power generation capacity provided by gas turbines operating alongside diesel generators in ‘combination of diesel and gas’ or ‘combination of diesel or gas’ configurations. However, as gas turbine efficiency is relatively low at partial loads, its use would most likely be limited to peak power demands.
The operation of gas turbines utilizing boil-off gases is well understood and has been successfully used for many years for power generation both in offshore as well as land-based applications.
Services for shipowners Strategic planning
• Risk management studies. Services helping shipowners to assess and manage risk; including: due diligence; port risk assessment; company risk management strategy; major disaster planning; reliability, availability and maintainability (RAM) studies; security assessment; and dependable system review.
• Technical investigations. Identifying and evaluating technical risks, and providing solutions to help shipowners manage the impact on their business.
• Integrated management systems. Helping shipowners to develop an integrated management system incorporating the international safety management (ISM) code, ISO 9001 and ISO 14001.
• Ship life extension studies. Evaluating the feasibility of ship life extension and associated risks.
• Design and regulatory advice. Advice on design and statutory trends, including: current design trends; impact of regulatory requirements; and forthcoming regulations.
Ship design
• Design appraisal services. Providing a design appraisal service using skilled and experienced personnel, including: assessing ship design (hull and machinery) concordance with Lloyd’s Register’s benchmark Rules and statutory codes; providing design advice; identifying critical areas;
improving detail design; problem solving, assisted by Lloyd’s Register of Shipping tailored software solutions, including: RulesCalc – an integrated Rule calculation package; ShipRight procedures and software – for advanced structural and fatigue analysis; and Rulefinder – consoli -dated Rule and statutory requirements.
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• Risk management studies. Services helping shipowners to assess and manage risk, including: risk management – design evaluation; hazard identification; risk assessment (design, operations, management); relia-bility, availability and maintainability (RAM) studies; identification of risk reduction measures; and fire and evacuation analysis.
• Technical investigations. Identifying and evaluating technical risks including: noise prediction and analysis; passenger and crew accom -modation comfort; design assessment, ship hydrodynamics, machinery dynamics, computational fluid dynamics; finite element and stress analysis;
concept design and vibration studies.
• Environmental services. Helping shipowners to manage environmental risks with: environmental protection notation; and environmental risk assessment.
Shipbuilding
• Construction survey. Managing the technical risks associated with new ships’ construction. Lloyd’s Register of Shipping’s unique knowledge and experience of design and construction helps ensure that their specialist surveyors offer practical solutions during construction through: on-site survey; construction monitoring, and focusing on critical areas identified at the design stage.
• Materials and equipment procurement. Services helping shipowners to ensure the quality of materials and equipment, including: works approval;
quality assurance scheme; and type approval.
• Technical investigations. Identifying and evaluation of technical risks, including: commissioning and sea trials; noise prediction and analysis;
passenger and crew accommodation comfort; dynamic testing (structure and machinery); materials investigation and laboratory services; specialist consultancy and problem solving.
• Shipowners’ project management and superintendent. Providing project management and superintendent services around the globe.
Operations
• Periodical survey. Maintaining shipowners’ vessel to Lloyd’s Register class – helping shipowners to manage their assets to the maximum,
• Periodical survey. Maintaining shipowners’ vessel to Lloyd’s Register class – helping shipowners to manage their assets to the maximum,