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1

Impact of late and early fuel injection on main engine efficiency and exhaust gas emissions

Pavin Z., Knezević V., Orović J., Valčić M.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2023

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Vol. 17 No. 1

177--181

EN

Exhaust gas emissions from ships are an aspect of the global maritime industry which has been given great importance in recent years. Increasing the efficiency of maritime transport regarding fuel consumption and exhaust gas emissions is an ongoing effort which requires a detailed analysis of all ship systems that have an effect on the aforementioned issue. One aspect that can be analyzed in this regard are the various machinery faults which influence the ships exploitation efficiency. This paper will focus on the analysis of the two stroke slow speed diesel main engine with early and late fuel injection faults. This analysis is based on a set of data acquired from a simulation model of a LCC tanker vessel including fuel consumption and emission pollutants such as carbon monoxide (CO), sulphur oxides (SOX) and carbon dioxide (CO2) as a greenhouse gas with early and late fuel injection fault introduced to different number of main engine cylinders. This methodology of research has the advantage of analyzing various scenarios which are not as easily reproduced on actual vessels.

2

Comparison of selected models useful in ranking the root causes of explosions in marine engine crankcases

Wiaterek Daniel, Chybowski Leszek

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2022

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nr 72 (144)

77--85

EN

This article aims to compile, describe and compare three different models taken from the literature describing the causes of explosions in the crankcases of marine engines. Each of the models has a different level of detail and was prepared with a different purpose. However, the same process, explosions in crankcases, was analyzed in all cases. A statistical evaluation of the frequency of events leading to explosions, a model built using failure mode and effects analysis (FMEA) and a model based on fault tree analysis (FTA) are described in turn. The FTA model drawn from the literature formed the basis for further analysis. Values of important measures of all elementary events of the fault tree were calculated using the Birnbaum reliability measure, Vesely-Fussell measure, Birnbaum structural measure, criticality measure and improvement potential. The percentage importance values of all events determined using these importance measures were compared. The results obtained from the application of each model were evaluated. The results of the models were compared with each other, and an approach using all three models supplemented with diversion analysis was proposed.

3

Assessing the topicality of the problem related to the explosion of crankcases in marine main propulsion engines (1972–2018)

Wiaterek Daniel, Chybowski Leszek

Zeszyty Naukowe Akademii Morskiej w Szczecinie

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2022

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nr 71 (143)

33--40

EN

The purpose of this paper is to present the results of a query aimed at assessing the validity of the topic of crankcase explosions prevention in the main marine engines. The study takes into account the engine type, engine manufacturer, ship’s age, accident severity, ship’s location at the time of the incident, and the share of fatal accidents in the analyzed population of crankcase explosions. One of the primary hazards associated with offshore and deep-sea ship operations – and primarily ship power plants – are fires and explosions that result in accidents and incidents with an average frequency of 60 days. This paper discusses the actuality of crankcase explosion hazards in the main propulsion engines of various types of sea vessels. The assessment was made based on the results of a statistical analysis of historical data from 1972 to 2018. The methodology consisted of three stages: (1) a selection query to obtain the source data, (2) analysis of the obtained results (data separation, extraction of additional information, and statistical analysis), (3) synthesis of the obtained information, and drawing conclusions about the numerical indicators describing the statistical distribution of individual events for the given evaluation criteria. The analysis showed that the risk of crankcase explosions affects ships of all ages – both in crosshead (31%) and trunk piston engines (61%) – and that the number of serious incidents (67%) remained constant over the investigated period. Half of all incidents occurred on vessels younger than 15 years old. 58% of explosions took place in engines of the most popular prime movers manufacturers. The probability that a main engine crankcase explosion will result in injury or death is 17.34%.

4

Studies on the effects of cold starts of the ship main engine

Adamkiewicz Andrzej, Fydrych Janusz, Drzewieniecki Jan

Polish Maritime Research

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2022

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nr 3

109--118

EN

This article presents the influence of various ship’s operational conditions occurring during manoeuvres related to entering and leaving the ports and mooring operations. Frequent starts and stops of the ship’s propulsion unit are then required, which affect the variability of the energetic loads of the ship’s power plant, causing accelerated, non-design wear of the ship’s main propulsion engine. The effects of cold start-ups of the main ship engine are the subject of this study. Conditions of the engine inlet valve damage process are discussed. The physics of the degradation process leading to air inlet valve damage was considered. Laboratory tests of structure continuity and their results are discussed, and the valve material defects were excluded as the cause of the damage. The causes of repeated damage to the inlet air valves were identified. The effectiveness of the performed corrective measures was confirmed by a documented control test of the engine start-up. The article is a utilitarian premise for the requirements of the Classification Society.

5

Monitoring the performance of a ship’s main engine based on big data technology

Liang Meng, Chen Mingzhi

Polish Maritime Research

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2022

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nr 3

128--140

EN

Under the recent background of ‘Green Shipping’ and rising fuel prices, it is very important to reduce the fuel consumption rate of ships, which is directly affected by the performance of the main engine. A reasonable maintenance schedule can optimise the performance of the main engine. However, a traditional maintenance schedule is based on the navigation distance and time, ignoring many other factors, such as a harsh working environments and frequently changing operating conditions, which will lead to faster performance degradation. In this study, a real-time evaluation method combing big data of ship energy efficiency with physics-based analysis is proposed to judge the degradation of main engine performance and assist in determining the maintenance schedule. Firstly, based on the developed ship energy efficiency big data platform, the distribution statistics and comparison of different operating states are carried out. Gaussian mixture model (GMM) and Density-Based Spatial Clustering of Applications with Noise (DBSCAN) are used to cluster the data and the high-density data areas are obtained as the analysis points. Then, the data of the analysis points are polynomial fitted, by the least square method, to obtain the propulsion characteristics curves, load characteristic curves, and speed characteristic curves, which can be used to observe the performance degradation of the main engine. The results show that this method can effectively monitor the degradation degree of the main engine performance, and is of great significance to fuel efficiency improvements and greenhouse gas (GHG) emissions reduction.

6

Impact of defective turbocharging system on the safety and reliability of large marine diesel engine

Anantharaman M., Islam R., Sardar A., Garaniya V., Khan F.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2021

|

Vol. 15 No. 1

189--198

EN

Today huge capacity sea-going vessels are propelled by mega high-powered marine diesel ‎engines, referred to as Main Engine. Turbocharging system is an integral part of large marine diesel engine plant, ‎contributing to their safety, reliability, and efficiency. Defects in the turbocharging system ‎could result in higher fuel consumption, erratic running of the Main Engine, and in the worst ‎scenario may result in the stoppage of the Main Engine at sea. An inefficient turbocharging system may also cause major damage to turbochargers, resulting in undesirable accidents out at sea. To ‎avoid such undesirable accidents and ensure smooth operations of the Main Engine, it is required to ‎address this concern. The aim of this research is to study the turbocharging system for a ‎large Main Engine using a Kongsberg engine ‎simulator. Various malfunction of the ‎Turbocharging system is considered, relevant data is collected and analysed. ‎Moreover, a Fault Tree Analysis, (FTA) is considered to identify the top undesirable event ‎which is the failure of the Main Engine. Based on the results of this study, various steps ‎are suggested to avoid failure of the Main Engine due to the defective turbocharging ‎system.‎

7

Potrzeby i możliwości udoskonalenia systemów diagnozujących okrętowych silników spalinowych o zapłonie samoczynnym

Girtler Jerzy

Journal of Polish CIMEEAC

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2020

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Vol. 15, no 1

24--45

PL

W artykule przedstawiono ogólnie własności współczesnych systemów diagnozujących (SDG) okrętowych siników głównych o zapłonie samoczynnym, potrzeby zastosowania SDG do sterowania procesem eksploatacji tych silników i propozycje udoskonalenia SDG dla potrzeb realizacji racjonalnej eksploatacji tego rodzaju silników. Zwrócono uwagę na potrzebę uwzględnienia we wnioskowaniu diagnostycznych wiarygodności diagnozy. Przedstawiono też korzyści wynikające z zastosowana w procesie decyzyjnym statystycznej teorii decyzji. Zasygnalizowano duży postęp w rozwoju systemów diagnozujących silników głównych na przykładzie systemów CoCoS firmy MAN SE (Maschinenfabrik Augsburg-Nürnberg)oraz CBM firmy Wärtsilä Corporation.

8

The impact of quality air in the engine room on the crew

Panaitescu M., Panaitescu F. V., Dumitrescu M. V., Panaitescu V. N.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2019

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Vol. 13, no. 2

409--414

EN

A The novelty of this study consists in the fact that, at the same time as the monitoring and acquisition of data of the air quality (from inside and outside), a monitoring and acquisition of data of the real-time biometric measurements of subjects exposed directly to the needle will be made. Medium by means of a bracelet attached to the subject's arm. This bracelet is designed to perform biometric measurements without creating discomfort to the subjects analyzed in the activities in which they are involved. This measurement is carried out with 9 different sensors for: pulse, oxygen in the blood, air flow (breathing), body temperature, electrocardiogram, galvanic skin response, blood pressure, the patient's position/movement, and the status of muscle (electromyography sensor). The data thus obtained will be focused on a PC and subsequently analyzed. The results of monitoring the health parameters of the subjects analyzed find application in the maritime field, to ships, especially in the engine room, where the air suffers quality transformations. The crew's return to the workplace may decrease due to the degradation of the air quality in the premises.

9

Simulation study on the Influence of EEDI requirements to shiphandling in heavy weather

Nishizaki C., Okazaki T., Yabuki H., Yoshimura Y.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2019

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Vol. 13. no. 4

855--860

EN

In order to reduce the CO2 emission from ships, International Maritime Organization executes the restriction of Energy Efficiency Design Index (EEDI) which limits amount of CO2 when freight of one ton is carried at one mile. Although the realization of higher efficiency of main engine without reduction of engine output is the best solution, it might be impossible. To comply with the EEDI requirements, it is assumed that the ship’s engine power becomes smaller than the existing ship by means of improving the ship propulsive efficiency. However, shiphandling in rough seas is expected to become difficult when the engine power is reduced. In this paper it is shown that the influence of the degraded main engine exerts on the safety of shiphandling in heavy weather based on the simulation study. In these experiments, both the simulation model that decreased engine power corresponding to EEDI requirement and that with the conventional engine power were tested, and masters in active service maneuvered the test ships in the rough seas.

10

Data analysis to evaluate reliability of a main engine

Anantharaman M., Islam R., Khan F., Garaniya V., Lewarn B.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2019

|

Vol. 13, no. 2

403--407

EN

Maritime transportation is the essence of international economy. Today, around ninety percent of world trade happens by maritime transportation via 50,000 merchant ships. These ships transport various types of cargo and manned by over a million mariners around the world. Majority of these ships are propelled by marine diesel engines, hereafter referred to as main engine, due to its reliability and fuel efficiency. Yet numerous accidents take place due to failure of main engine at sea, the main cause of this being inappropriate maintenance plan. To arrive at an optimal maintenance plan, it is necessary to assess the reliability of the main engine. At present the main engine on board vessels have a Planned Maintenance System (PMS), designed by the ship management companies, considering, advise of the engine manufacturers and/or ship’s chief engineers and masters. Following PMS amounts to carrying out maintenance of a main engine components at specified running hours, without taking into consideration the assessment of the health of the component/s in question. Furthermore, shipping companies have a limited technical ability to record the data properly and use them effectively. In this study, relevant data collected from various sources are analysed to identify the most appropriate failure model representing specific component. The data collected, and model developed will be very useful to assess the reliability of the marine engines and to plan the maintenance activities on-board the ship. This could lead to a decrease in the failure of marine engine, ultimately contributing to the reduction of accidents in the shipping industry.

11

Operational verification of a ship main power system element choice : case study

Adamkiewicz Andrzej

Journal of KONES

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2019

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Vol. 26, No. 4

7--14

EN

The article refers to results and conclusions on post-emergency repairs of a turbo-charging system of a DEUTZ engine of the SBV 8M 628 type of 1715 kW – the main power unit of a cement carrier. The failure of the turbocharger led to severing of a part of the exhaust outlet valve head. In order to determine the cause of the turbocharger fault, parametric identification of the reference state of the turbocharging system interacting with the ship main power engine has been carried out. The post-emergency servicing of the turbocharger comprised mounting a new blade rim of expansive instruments of smaller capacity than the so far used. Control measurement results of the power system after the replacement of the turbocharger turbine nozzle have been presented. Limitations of correct engine operation have been noted in the range of maximum load with continuous power (MCR). A range of corrective maintenance servicing of fuel equipment has been presented. Using the values of measured torque at the propeller shaft, incorrect interaction between the shaft and the main engine has been noted. A new propeller, adequate to the design operational parameters of the engine characteristics, has been chosen and mounted. The correctness of turbine expansive instrument replacement has been verified by correct interaction between the elements of the power system: propeller – main engine – turbocharging system. Thus, a wider range of economically acceptable ship operation has been obtained.

12

Reliability Assessment of Main Engine Subsystems Considering Turbocharger Failure as a Case Study

Anantharaman M., Khan F., Garaniya V., Lewarn B.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2018

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Vol. 12, no. 2

271--276

EN

Safe operation of a merchant vessel is dependent on the reliability of the vessel’s main propulsion engine. Reliability of the main propulsion engine is interdependent on the reliability of several subsystems including lubricating oil system, fuel oil system, cooling water system and scavenge air system. Turbochargers form part of the scavenge sub system and play a vital role in the operation of the main engine. Failure of turbochargers can lead to disastrous consequences and immobilisation of the main engine. Hence due consideration need to be given to the reliability assessment of the scavenge system while assessing the reliability of the main engine. This paper presents integration of Markov model (for constant failure components) and Weibull failure model (for wearing out components) to estimate the reliability of the main propulsion engine. This integrated model will provide more realistic and practical analysis. It will serve as a useful tool to estimate the reliability of the vessel’s main propulsion engine and make efficient and effective maintenance decisions. A case study of turbocharger failure and its impact on the main engine is also discussed.

13

The increase of operational safety of ships by improving diagnostic methods for marine diesel engine

Witkowski K.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2017

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Vol. 11, no. 2

317--321

EN

This article shows the importance of the diagnostic improvement methods of marine engines to boost the economy and safety of operation of marine cargo ships. The need to implement effective diagnostic methods is justified by presenting statistical data of marine diesel engines failure and the cost of their operation. Based on the own research has been proven, for the chosen example, that indicator diagrams and analysis of indicated parameters have limited utility in the diagnosis of damages of marine engine, although this is a method commonly used in operational practice. To achieve greater diagnostic effectiveness, when, based on indicator diagrams, are calculated and then the characteristics of heat release is analyzed - net of heat release characteristics and the intensity of the heat release, it was demonstrated. This procedure is particularly effective in the diagnosis of damage of injection system components marine diesel engine.

14

Charging station location optimization of electric ship based on backup coverage model

Zhang W., Yan X., Zhang D.

TransNav : International Journal on Marine Navigation and Safety of Sea Transportation

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2017

|

Vol. 11, no. 2

323--327

EN

In terms of electric ship energy requirement in navigation, the ship charging station location is especially important. In this paper, a multi-period ship charging station location optimization model is pro-posed to make location decision in overall, from initial possible station sites chosen to the capacity determination for the final location sites. In the first phase, from the perspective of external environment, find out all possible ship charging station candidate sites through the feasible analyze. In the second phase, taking the ship charging demands into consideration, the final ship charging station sites can be selected among the candidate sites based on backup coverage model. In the last phase, regarding the cost of construction and service capability for different grade as the main factor in capacity determination, the optimal capacity of each final ship charging station are determined by means of optimization method. Finally, an example of Yanqi lake in China is used to verify the validity of the proposed methodology. The reasonable location of charging station could ensure the electric energy supply and avoid congestion caused by ship charging gathering. The model can be easily generalized to other problems regarding facility allocation based on user demand.

15

Fault Tree Analysis as a tool for modelling the marine main engine reliability structure

Laskowski R.

Zeszyty Naukowe Akademii Morskiej w Szczecinie

|

2015

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nr 41 (113)

71-77

EN

The introduction to the Fault Tree Analysis has been presented in this article. Selected publications on the Fault Tree Analysis have been listed. The usefulness of the method in marine engineering application has been indicated. Reliability testing facility has been presented, that is typical two-stroke, slow-speed ship crosshead Diesel engine intended to power the ship. The way of creating system model with the Fault Tree Analysis application has been presented. Reliability structure of tested engine has been modelled using Reliability Block Diagrams, as well as the Fault Tree Analysis. Main tree describing the object reliability structure analysis and the sub-tree structure modelling crank system, subsystem of the cam shaft, cylinder exemplary system and turbocharger have been built. Qualitative analysis of the tree has been conducted – the minimal cut sets of the system has been determined. The directions for further research have been indicated.

16

Koncepcja siłowni okrętu wsparcia

Rzemykowska M., Wontka L.

Logistyka

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2014

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nr 6

1109--1115, CD 2

PL

Okręt wsparcia we współpracy w ramach zintegrowanych działań sojuszniczych jest jednym z podstawowych wymogów technicznych stawianych przed członkami NATO. Marynarka Wojenna wprowadzając takiego rodzaju okręt sprostałaby potrzebom zapewnienia wsparcia logistycznego jednostkom biorącym udział w działaniach. W artykule zawarto koncepcje rozwiązania siłowni okrętu wsparcia. Na podstawie wykazu jednostek podobnych obliczono moc napędu głównego przez co dobrano silniki główne. Dobrano również inne urządzenia siłowniane.

EN

Memeber States of NATO are obliged to take part in joined operation. Support ship is one of the basic requirements to cope with this task. Polish Navy introducing this type of ship would satisfy the demands of logistics support to the warships participating in the joined operation. The article present conceptions of engine room proper to a specific requirements of support ship. On the basis of a list of similar ships propulsion power was calculated and the main engine was chosen. Other engine room equipment was also indicated.

17

Modern actuator

Mielewczyk A.

Journal of KONES

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2014

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Vol. 21, No. 2

221--226

EN

The main engine of the ship is a complex technical object, which provides propulsion of the screw and ensures the safety of a ship at sea. It consists of a number of control systems such as lube oil temperature control, temperature control of the cooling water, fuel viscosity control or adjustable speed control of the main engine. Each of the main propulsion control system affects the safety of the ship. Continuous automation systems are built with standard transducer of measured quantity, the controller and actuator. The actuator is responsible for the direct setting of the size of the control object. The actuator is connected to the control valve and the actuator position change translates into a change in the flow rate of the working medium. Thus, the operating element is required to operate in the linear characteristics of the standard signal range. From the other hand, the control valve provides flow characteristics linear or of equal percentage. This control principle of medium flow is used in various control systems. The actuator of the control valve is always equipped with a positioner, which corrects errors in the position of the valve relative to the input signal. The presented design of the motorized valve is an analog system. Using the technique of converting multiple digital signal causes the system complexity and predisposition to damage. Eliminating the intermediate elements can improve the quality control and system safety. Then it is beneficial to have a design of the operating element based on the direct digital processing unit. The aim of paper has been to present design of the valve actuator, which completely abandons the digital-to-analogue convertor. The new design should increase the level of security of the system and quality control. The design layout is presented in the article. The new actuator is on-off valves, which control, directly from the digital bits, the form of the output signal. The control signal may use the control algorithms to be used or developed individually to the actuator design.

18

Measures for estimating transport vessels operators' subjective preferences uncertainty

Goncharenko A. V.

Prace Instytutu Lotnictwa

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2013

|

Nr 1 (228)

13--21

EN

The pseudo-entropy hybrid model is suggested as the measure of uncertainty of operators' subjective preferences. Because of the introduced relative prevailing preferences factor the proposed hybrid model has advantages comparatively to the traditional measures of uncertainty in the view of Boltzmann's or Shannon 's entropy. According to the relative dominating preferences index the pseudo-entropy varies within [-1...1] showing the sign and magnitude of the relative subjective assuredness. Analytical expressions have been achieved. The theoretical concept is illustrated with examples and graphs.

19

The researching ship “Gdynia“

Gierusz W., Łebkowski A.

Polish Maritime Research

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2012

|

S 1

11-18

EN

The paper presents the physical model of the sea-going ship. The wooden hull of this ship was obtained from Ship Design and Research Centre and next rebuilt and reconstructed for future tests of the different control systems in the real-time experiments. The paper describes the succeeding stages of the work, steering and driving devices installed on board, power electric diagrams and navigational equipment designated for ship. The range of the possible applications of the constructed vessel are presented at the end of the paper

20

Risk criteria for sea-going ships arising from the operation of the main engines'crankshaft - connecting rod - piston systems

Liberacki R.

Journal of Polish CIMAC

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2012

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Vol. 7, no 2

115-121

EN

In the article the risk criterion for sea-going ships arising from the operation of the main engines’ crankshaft – connecting rod – piston systems is proposed. This criterion is based on the procedures recommended in the Formal Safety Assessment method developed under the auspices of International Maritime Organization (IMO). First of all the collective risk criterion for ship has been proposed. In the next step, the share of the main engines’ crankshaft – connecting rod – piston systems, as the causes of marine accidents has been estimated. Then the risk criteria for ships arising from operation of those systems have been created. Additionally the reliability requirements for main engine components have been established.