Table of content

In the abstract the results of studies are presented for limit values of intensity of gas blows-by through the crankcase of a piston combustion engine with spontaneous ignition in the starting phase. Attention is drawn to the fact that determining the blow magnitude during start-up is of a particular value concerning the state of the piston – ring – cylin-der system.

The paper demonstrates the influence of oxygen and carbon dioxide on corrosion processes in ship’s auxiliary boilers. The influence of feed water temperature on degas-sing and on increase of boilers steam output were analysed. A constant feed water tem-perature system was proposed.

It has been shown that the concept of exergue can be used in the analysis of ther-mo-dynamic efficiency. The concept incorporates both principles of thermodynamics. The factor of exergue efficiency is shown. The developed technique of defining the values of exergue losses occurring at the utilization of heat of internal combustion engine ex-haust gases is based. The technique is based on the entropy method. The obtained de-pendences determining the influence of various factors have been presented as well.

The paper demonstrates the influence of soot deposits on the heating surfaces of chosen exhaust gas boilers on the exhaust flow resistance and boiler capacity. The results of computer simulation were compared with experimental results.

This paper introduces the partial results of research, showing possibilities of acous-tic emission use to the diagnosis of the fuel injection systems of marine diesel engines. By means of a suitable signal process we can get to the source of acoustic emission signals dependent on varying kinds of faults in the injection system

In the article an attempt was made to use some time-frequency methods for the analysis of acoustic emission signals. Concerning the field of interests measurements were taken of some ship machinery and equipment. Signals coming from the fuel injec-tion systems of ship diesel engines, roll bearings and gear were analyzed. They were pre-selected in regard to their usefulness for diagnostic purposes.

The paper presents the results of simulation research based on static characteristics determination for the type series of cylindrical fenders. The discretization by finite ele-ments of geometrical model of cylindrical fender plane section was performed, taking into account hyperelastic elements and contact phenomena. The deformations and curves of the characteristics achieved in numerical calculations and experimental meth-od is presented.

The development of marine propulsion systems is prognosed in relation to the fuels of the near future. Presented is a concept of a subsystem supporting the maintenance of present and future propulsion systems. The author also demonstrates the achievements of the Maritime University of Szczecin in the designing and implementation of a system for marine propulsion system maintenance support.

In the article the method of diagnosing failures of automotive gearboxes was intro-duced. This method applies to production processes during final quality control. The method of diagnostic signal processing with the use of amplitude demodulation and autocorrelation function was described in detail. Moreover, the procedure of diagnostic deduction and algorithm of gearbox failure identification was presented.

This article describes a ship course stabilization system. It is based on the comput-er-borne dynamical model. Such an approach, which uses also the fuzzy sets theory, forms a new and original way of constructing a control algorithm. The computer ship model is simplified, i.e. it does not take into account the dynamics of the steering gear. The algorithm quality has been verified via simulations and compared to the LQR regu-lator.

In order to improve the reliability of the engine system, a new technology for engine control is needed. One of the methods used to meet this requirement is to develop a con-venient and real-time measuring system. The equipment can be used in order to evaluate engine performance. Conventional calculations based on the pressure-volume diagram require a high-speed central processing unit (CPU) and a high accuracy measurement instrument. This paper presents some interference problems with combustion pressure measurement and analysis.

The marine diesel engine today is the prime mover for ship propulsion. The most typical marine propulsion plant of modern merchant ships is a single, slow-speed turbo-charged, two stroke diesel engine, directly coupled to the vessel’s single, fixed or con-trollable pitch propeller. This configuration can provide high power outputs and im-proved fuel economy. The paper deals with basic ship propulsion factors used for fuel consumption calculations.

The paper presents solutions for describing the processes of distorted plates with large plastic deflections. The solution was obtained using the concept of “momentary opening of plastic hinges”, which allows to estimate deflections of a plate subjected by various forms of operating loads, with various initial deflections and various boundary conditions.

The paper presents a mathematical model which makes it possible to describe the process of damage to vessel hulls making it explicit in time, which is based on a Poisson stream. It allows one mathematically to forecast volumes of damage of vessel hulls and to evaluate their technical condition on the basis of probability criteria.

In the paper an attempt was made to find relations between acoustic emission signals measured on parts of the thruster and forces associated with its operation. Presented results will be used in the diagnostic model of marine thrusters.

This paper presents aspects of diagnostic susceptibility illustrated with hydraulic systems of excavators. The presented factors of diagnostic susceptibility are used for the estimation of economic effectiveness of technical diagnosis.

Cavitation-corrosion wear phenomena are one of most common reasons for accel-erating the cases of failure in liquid cargo transportation appliances. Test-rig designs are based on methods of examining the mechanical processes extended with chemical or electrochemical influences. The elimination of uncontrolled electrochemical effects is the most important problem. The paper presents a review of typical solutions of test rigs intended for the research of cavitation-corrosion wear.

The concise list of basic groups of wear phenomena is presented. These exist in installations intended for the transportation of liquid cargo in the marine environment. The basic role of synergic phenomena in the processes of accelerated wear is discussed. The need of including the complex wear phenomena into teaching programs is indicated

The optimizing of repairs is the essential task in companies because, on the one hand they generate costs, but assure stable income on the other hand. This article shows a model of standard costs calculation useful in the management of machine repairs.

Experimental research on vibrations in ship’s living quarters was done. The technique of designing deck overlaps of commercial ships with the improved vibrating characteristics is developed.

This article presents a way of applying a neural classifier constructed on the basis of a counter-propagation neural network in vibroacoustic diagnosis of toothed gears. In the final part of the article the results of a laboratory experiment are presented.

Two integrated propulsion systems manufactured by MAN B&W and Wärtsilä, re-spectively, are compared. The advantages and disadvantages of these systems are dis-cussed. Some operational problems are indicated. The presented systems are illustrated.

This paper presents basic information on the structure of diagnostic tests used for the assessment of the technical state of parts and groups of technical systems. The Bool-ean matrix method is also demonstrated. The construction of bond graphs and state equations, which can be tools for the assessment of technical condition of machines has been presented

This paper presents results of research on inter-metallic Fe-Al alloys cavitational erosion resistance, using the flux-impact measuring device. These inter-metallic alloys are proved to have good resistance from this type of erosion in comparison with other construction materials. It was found that this is an advantageous influence of the laser-melted zone of cavitational erosion resistance of inter-metallic FeAl23 alloys.

The paper contains a comparative analysis of parametric sensitivity of rheological and physical model of vibration mounts for vibration isolation systems with linearly changing properties versus the frequency of forces.

This paper contains a description of an identification method for prismatic rubber vibration mounts of Young’s modulus and loss factor calculated on the basis of physical model narrow band transmittance for vibration mounts, which takes vibration mount mass influence into consideration.

The development of the systems of air-supply and gas-turbo-superchargers is shown through an analysis done in field operation and failures caused by the gas-turbo-superchargers and supercharging systems. An analysis has been performed aiming at emergency prevention measures.

The Polish Standard-based definition of dust has been given. Attention has been drawn to the fact that certain classes of dust granularity have adverse effect on living organisms as well as on marine machinery components. The way dusts affect lubricated parts has been shown. The abrasive action of dusts is due to their considerably higher hardness than that of metals. A brief review of air filters in the engine room is provided. Possible applications of a two-stage dust separator (axial cyclone-fabric dust cleaner) are shown as the efficiency of the combined filter is much higher. Indicated are grain composition classes causing particularly intensive wear of machine components.

This paper presents the results of numerical solutions modified by Reynolds equa-tion of laminar unsteady lubrication of a cylindrical slide journal bearing. The particu-lar solutions are limited to isothermal models of bearing with infinite length lubrication by newtonian oil with constant dynamic viscosity. The disturbances are related with unsteady velocity of oil flow on the sleeve and on the journal. The results are shown in the diagram of hydrodynamic pressure in the dimensionless form in time intervals of displacement duration.

Electro-spark formation of hardening layers is based on erosion of the anode mate-rial during a discharge of electrical sparks. In the process hard alloys of titan-cobalt and tungsten carbides have been used as the anode. As the result we get a surface with good bonding to the substrate and high micro-hardening

A statistical analysis of changes made in operational parameters of various kinds of lubrication oils produced by Western firms used in marine piston diesel engines has been completed. Analytic ageing indexes of these oils in tested engines have been calcu-lated.

The work presents threats connected with the spills of noxious oily chemicals at sea. Physical phenomena occurring during spills are described. Physical and chemical prop-erties of some dangerous substances are listed. The list of dangers posed by these sub-stances (acc. to GESAMP) is included and the methods used for the clearance of spills as well as the duties of ship-owners of ships carrying such chemicals are presented.

In the past years designers' efforts was directed into the reduction of toxic com-pounds produced by vehicle combustion engines. The paper introduces the influence of combustion engine process as well as putting out of combustion process order on growth of toxic compounds emission.

Selected definitions of technical systems have been characterized. Some of the rela-tions in technical systems have been presented. Models of systems, which can be applied in marine power plants’ research, were demonstrated. Formal tools used for the model-ing of technical systems were also presented.

The article shows methods and means of investigations of the technical state fea-tures of marine medium-speed engines, which were withdrawn from operation. Meas-urements of selected features of state were realised through geometrical and flow test-ing. Examples of the results give information about ranges and distributions of the wear and failures of injection nozzles.

The paper presents a method of predicting the annual emission of toxic compounds contained in exhaust gases from an auxiliary boiler, based on sea trials and ship’s op-erational data.

During recent years computer maintenance management systems in enterprises have been changing significantly. These systems were successfully applied to many branches of industry. It seems to be inevitable to implement these systems for ship maintenance. When maintenance management systems are implemented it makes it pos-sible to optimise the following: inventory management, delivery management, outsourc-ing and maintenance tasks, what affects the economical effects of enterprise.

The present article provides a technical foundation of the principle of mini-max value for the selected criterion to establish a check schedule on the state of the system. The example of a determination of the number of checks and periods of check perfor-mance of the certain systems is analyzed in the article.

This paper is concerned with diagnostic methods, the goal of which is to detect initial structural faults, characterize their nature and severity and isolate them into particular components. The analysis presented here focuses on a means of vibro-acoustic signals, specifically, on a means of extracting from such signals the information concerning physical interpretation of wear phenomena impact on signal generation. It demonstrates that such diagnostic information can be extracted using a fractional derivative methodology and that the technique can be useful in choosing the structure of a diagnostic model.

The article presents some problems with O-ring type seals that are in common use in marine machines. Typical failures of elastomers and their causes are discussed. Atten-tion is drawn to correct assembly of o-ring seals in static and movable joints.

This article presents possibilities of diagnosing an impeller pump by means of the measurement of liquid elevation energy, delivery of a pump and hydraulic losses. The selected parameters can be expressed by dimensional functions, which are trans-formable to algebraic functions. The method of dimensional analysis was used in the transformations. The obtained functions can be used for monitoring the work of an im-peller pump in ship installations.

The paper presents basic information on the prognosis theory in the aspect of tech-nical condition estimation. The prognosis definitions have been given and classification of prognosis methods has been shown. Selected prognosis methods have been shortly described. Algorithms of prognosis procedures have been described.

Expenses to maintain machines and plants are immense, and further expenses are necessary to assure their availability during operating time. The question is exactly which people can be employed for such tasks and how can they motivate themselves to achieve such tasks by rational expenditure. It is also a clever idea to exchange their experiences of global or local employment. Can such a society give the much-needed support?

The article deals with possible applications of procedures for the identification. The algorithm of procedures optimization for assumed quality criteria of optimization task solution. is considered.

The paper presents assumptions taken into consideration while designing a test stand for research work. The specific test stand described in the paper will serve for investigations of de-oiling processes carried out by various separation appliances. The test stand will also allow testing of a separation unit in accordance with the MEPC.60(33) Resolution and the latest MEPC.107(49) Resolution.

Taking into account that the ship dynamics’ identification process is such an ardu-ous task the paper proposes a ship course stabilization algorithm based on the intelli-gent control concept. Such an approach makes it possible for an on-line control algo-rithm synthesis even in the case of the absence of a ship’s dynamical model structure.

Some problems of troubleshooting relating to the technical state of machines by methods of identification and diagnosis are introduced. Relationships are shown be-tween methods of dynamic state evaluation and methods of operating state evaluation. Examples of the modal analysis show the complexity of problems of representing the evaluation of machine dynamic state in diagnostic examination of machine technical state.