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Results are presented from two-phase flow wax deposition tests using a state-of-the-art high-pressure multiphase flow test facility. Wax deposition was found to be flow pattern specific and dependent on the flow velocities of the two-phase fluids. Wax deposition occurs only along the pipe wall in contact with a waxy crude oil. An increase in mixture velocity results in harder deposits but with a lower deposit thickness. The wax buildup trend at low mixture velocities is similar to that observed in laminar single-phase flow tests. The wax buildup trend at high mixture velocities is similar to that observed in turbulent single-phase flow tests.

Heavy sea states and severe weather conditions have caused the loss of more than 200 super carriers within the last 20 years. In many cases single 'rogue waves' of abnormal height as well as groups of extreme waves have been reported by crewmembers of such vessels. The European Project MAXWAVE dealt with both theoretical aspects of extreme waves as well as new techniques to observe these waves using different remote sensing techniques. The final goal was to improve the understanding of the physical processes responsible for the generation of extreme waves and to identify geophysical conditions in which such waves are most likely to occur. The results of the MAXWAVE projects are summarised with emphasis on the analysis of the marine and satellite radar data sets. 2D sea surface elevation fields are derived from marine radar data and complex SAR spaceborne (synthetic aperture Radar) images. Several ship and offshore platform accidents are analysed and new warning criteria are discussed.

One of the most challenging issues in the offshore oil and gas industry is corrosion assessment and management in subsea structures or equipment. The aim of this study was to investigate the corrosion progress characteristics of offshore oil well tubes used in the production of oil in deep water. A direct measurement database of corrosion damage in terms of pit depth with age (time) in offshore oil well tubes was collated. The corrosion data were statistically analysed to identify the probability density distribution of corrosion damage with time. An empirical formula to predict time-dependent corrosion damage in offshore oil well tubes is suggested based on the results of the statistical analysis. Given that there are few corrosion measurement databases of subsea equipment used for offshore oil and gas production in the literature, this study should prove useful for assessing and managing corrosion damage in deep water offshore oil well tubes, which are key pieces of equipment in offshore oil and gas production systems.

OSV (offshore supply vessel) is a vessel which is used for the transportation of stores materials equipment or personnel to from and between offshore installations. The transportation of fresh mud and ordinary drilling brines are harmless enough. However due to the additives acids emulsifiers and other chemicals used in the drilling fluids the existing mud and brine tanks on the OSV are not equipped for the transportation of back loads of contaminated mud and brines. Charterers and operators of OSVs and rigs are not well versed in the requirements for the transportation and containment of hazardous and noxious liquid substances in the OSV. Masters of OSVs should not accept the loading of any cargo unsafe for handling or improperly documented. The responsibility for ensuring that cargoes are suitable for carriage rests with the operator shipper or owner of the cargoes. All parties should be aware of the IMO Codes and conventions for the safe carriage of these cargoes. The port authorities will bar ships carrying them unless they discharge to approved reception facilities for treatment recycling or disposal. The dangers guidelines and simple approaches to meet this challenge are highlighted.

The development of a new ASIC intended for use in Smart Sensors and Fieldbus Sensors is described. This single chip will to a large extent replace the discrete electronics now used in standard signal converters and smart sensors and will allow for reduced cost smaller size and improved reliability in harsh environmental conditions. The ASIC includes programmable analogue input circuitry as well as processing capacity and bus interfaces. Up to four sensor elements can be connected to each ASIC. A number of engine builders are now working with fieldbus-systems which connect modular I-O-units on the engine to the alarm and monitoring system. Redundant fieldbus systems are also introduced in the control systems of the engine. The motivation for this transition is reduced costs and improved performance. By introducing this new ASIC which is small and robust enough to be integrated into the sensor itself or in the sensor plug connector the specific I-O-units can be omitted and improved quality control of sensor data and automated fault diagnostics can be obtained.

An alternative solution for maintaining supply to offshore wind turbines under fault conditions using the wind turbine generator itself as a source of power is presented. Econnect Ltd has developed dynamic load control and synchronous compensator equipment to provide frequency and voltage control enabling wind turbines to be operated safely in islanded mode. Design modelling and site work conducted to operate a 300kW pitch regulated wind turbine in islanded mode situated on the harbour wall at Blyth is looked at. After some introductory information attention is given to the islanding concept. Next a site description is given. Computer simulation is considered followed by site installation/testing and site results.

The design methodology for reinforcement of openings in hot tap tees is usually done according to equivalent area replacement. This methodology is specified by numerous codes. Pipeline codes utilize safety factors that are intended to reduce the working stress to which the pipeline is exposed. Results of a parametric study aimed at determining the relative effect of reinforcing saddle branch and run wall thickness is presented. The results demonstrate that the use of more conservative safety factors can actually lead to higher stresses in critical locations - i.e. opposite to the desired effect. Instruction is provided on design choices that can be made to correct these deficiencies. Recommendations are given for further investigation.

Eighth Int Symp held in Durham 9 - 11 Sept 1986 Papers are A laboratory study of high pressure water jet assisted cutting Application of water jet technology at coal mines in Japan - water jet drilling for large diameter stress relief borehole in coal seam Water jet assisted drag tool cutting - parameters for success Horizontal water jet exploration of burning coal seams Water jet assisted rock cutting - the effect of pick traverse speed High pressure water assisted rock and coal cutting with boom type road headers and shearers Preliminary study on the abrasive water jet assist roadheader The development of a water jet assisted shearer loader Longwall shearer performance using water jet assisted cutting An investigation into the effect of varying water pressure and flow rates upon the release of airborne respirable dust by a Dosco MK11B roadheader equipped with a water jet assisted cutting head The use of abrasive entrained high pressure water jets as a tool for the non explosive winning of gold bearing quartzites

KCLs (kinematical conservation laws) giving the successive positions of a moving curve in a plane are used to describe all possible geometrical shapes of the crest-line (the line joining the highest points) of a curved solitary wave on shallow water. The KCL is an under-determined system of two equations. It is assumed that the length of the curved solitary wave in the direction transverse to the direction of its propagation is very large compared to a length measuring the breadth of the solitary wave. This allows a section of the solitary wave to be treated by a plane perpendicular to the crest-line as a 1D solitary wave and helps an additional relation to close the KCL to be found and the problem to be solved completely.

It is now widely accepted that for some species a proportion of the undersized fish escaping trawl codends die as a direct result of stress with 10% to 30% mortality commonly cited. It has also been suggested that there may be indirect or behaviourally mediated mortality; fish that encounter and escape the trawl only to experience stress-induced behavioural deficits and succumb to predators in the hours or days afterwards. The goal of this review was to evaluate the plausibility of this behaviourally mediated yet unobserved mortality. Three laboratory studies using cod walleye pollock and sablefish have assayed for behavioural impairment in fish following application of stressors designed to simulate entrainment and escape from trawls. This review focuses on these three studies but also integrates relevant literature that addresses stressors experienced by fish during their entrainment and subsequent escape from trawls as well as more generic studies of stress-induced behavioural impairment in fish.

The recent development of offshore LNG terminals has lead to increased focus on hydrodynamic modelling tools for floaters in shallow water. Special effects that are different from 'traditional' offshore technology in deeper water make it necessary to address these topics. In particular low-frequency wave drift forces need to be studied. Model testing is essential in validation of numerical prediction tools for these problems. Wave-group-induced low-frequency wave components is an important part of the problem. Their reproduction in laboratories needs special attention. In general two types of low-frequency waves are present: 'bound' waves following the wave groups and 'free' waves propagating with their own speed. The former is included in second-order numerical codes for floaters while the latter is normally not. Therefore identification and possible reduction of the free components is of interest. A practical way to do this in a large wave basin is described. Results from generation of bi-chromatic waves without and with correction are presented. Corrected results show a clear reduction of the free wave component.

The contents of the book are arranged in two parts. The first includes chapters on: diesel engines for stationary plants - land engines; marine diesel engines; fuels for diesel engines; thermodynamic cycles; efficiencies and the calculation of cylinder dimensions. The second part covers all the parts of a diesel engine, including bed plates, crankshafts, cylinder heads, valves, self-actuating gears, fuel injection pump, compressors. Later chapters deal with the layout and specifications for the engine room and marine engine room installations. An appendix to this deals with the Rules of Classification Societies for the construction of marine oil engines. The last chapter looks at tuning-up and testing and trials of diesel engines.

The aim of the book is to demonstrate the principles which dictate development of furnaces for large boilers. Contents are arranged in two parts. The first part is on Theory and components of furnaces for large boilers. The introductory chapter of this part deals with the principles and functions of large boilers and furnaces. The next chapter looks at types of large boiler furnaces and preheaters (dry-bottom, slagging or wet-bottom, cyclone and oil and gas fired furnaces). The following chapters examine: Heat release in furnaces; Fuel preparation, burners and air supply; The heat absorbing surfaces in the furnace; Mineral constituents of combustion residues, Discharge of combustion residues, Treatment of solid combustion residues and Furnace dynamics including control. Part 2 is about Existing Installations and contains the following chapters: Dry-bottom furnaces, Wet-bottom or slagging furnaces and Large boilers for several fuels (combined coal-oil and coal-gas).

Offshore areas are becoming increasingly important for the installation of new wind parks. One complex and difficult offshore condition relates to the foundation of the support structure mostly designed as monopile structures. Such monopile support structures for offshore wind turbines in areas with movable sand beds may be affected by local scour processes due to wave and current action. An innovative scour protection for monopile structures using geotextile sand containers was recently proposed. Large-scale model tests on the stability of such alternative scour protection are being carried out. The experiments are described. Results are presented and discussed.

Laser line scan (LLS) is an optical system for observing the sea floor. A rotating prism in a towed fish sweeps a laser beam across the bottom. The return signal is received at the fish and can be enhanced digitally using sophisticated image-processing techniques. Laser line scan's coverage rate is much higher than video mounted on a ROV (remotely operated vehicle) and approaches that of sidescan sonar. The images are of higher quality than sidescan and are easier to interpret because they are optical rather than acoustic. The high power of the laser allows the system to be three to five times further away from the target object than video and it has been demonstrated to be effective even in murky water. Laser line scan was developed for military purposes and has been applied in underwater search pipeline surveys geotechnics archaeology and biology.

A significant amount of capital has been invested to develop the vast pipeline infrastructure needed to meet the requirements of the modern world. The maintenance of this infrastructure is vitally important to its economic welfare as the financial impact from deferred production due to shut down can be substantial not to mention the environmental damage and potential loss of life should leakage occur. When leaks do occur the options available for sealing have traditionally been based around external procedures such as wrapping and isolating the leakage or leak sealing clamps requiring divers or expensive ROV and DSV equipment. This approach relies on direct access to the leak location which for bundles and umbilicals may be impossible. Brinker Technology a multi award winning British company has developed an innovative solution to this problem using their patented platelet technology which offers a totally unique integrity solution to the pipeline industry world-wide. Platelet technology is a unique and innovative method of sealing and locating leaks in pressurised pipelines.

NOTE - This is a BMT duplicated conference holding thus papers abstracted in Chapter 26 are: Cargo operations - lessons to be learnt Learning from the port experience Do we ever learn? - the perspective of the Salvage Association Learning from marine accidents: the work of the Marine Accident Investigation Branch The maritime black box: a shipborne voyage data recorder dedicated to maritime accident investigation Offshore safety Developments in active smoke control systems for passenger vessels Occupational accidents among seafarers Safety management of the mustering and evacuation of damaged passenger ships -MEPdesign on the development of a tool box International marine accident reporting scheme MARS: lessons from MARS IMISS: an i nternational maritime information safety system - the next safety frontier Integrated safety investigation methodology (ISIM) - a systematic approach to learning from accidents A new methodology for marine casualty analysis accounting for human and organisational factors Risk assessment in the fishing industry Are current risk management strategies within the commercial shipping industry adequate? Formal safety assessment: its role in marine safety The work of the marine forensic panel

In March 1991 the UK Australia Norway and Hong Kong formed a group to revise the Dynamically Supported Craft (DSC) Code and change it to the Code of Safety for High Speed Craft as a result of the Apollo JetCat catamaran accident in December 1989. A Marine Court of Inquiry determined that the maloperation of of a single switch caused the wheelhouse controls to fail and the vessel was unable to control its speed direction or stop. Hong Kong is now acting upon the Inquiry findings and has made submissions to the IMO subcommittee on ship design and equipment. This paper examines the lessons to be learned from the casualty and they range from design through to operation and training. Operator errors and cause of the point failure are detailed.

An evaporating diesel spray of a common rail injector was visualised using the LIEF (laser-induced exciplex fluorescence) method. The experiment was carried out in a constant volume vessel to maintain high-temperature and high-pressure conditions. The relative SMD distribution of the spray in liquid phase was obtained by the ratio of the intensities of the fluorescence and the Mie scattering. The effects of changes in injection pressure and ambient gas pressure on spray structure were investigated. A simulation study was carried out using the modified KIVA-2 code. The results of simulation were compared with experimental results. The calculated results from the modified KIVA-2 code agree with the experimental results comparatively.

The paper (pages 1-11) is followed by 3 pages of diagrams (pages 12-14). The subsea development of large ultra deepwater fields requires high specification flowline and riser systems to cope with the many changes in requirements. Several new technologies have recently been developed to provide lighter and more efficient flexible pipes. The solutions now available for resisting hydrostatic collapse at deep water depths are described. These include higher strength materials and steel wires with innovative profiles. The new tensile armours which have been developed on the basis of composite material with carbon fibres are also presented. The CSO light-weight flexible pipe for ultra deepwater applications is described along with its advantages in comparison with more conventional flexible pipes.