Papers by Keyword: Shipbuilding

Abstract: This study investigates the thermal field of S355J2+N steel plates for shipbuilding applications welded with automatic welding equipment. Real-time thermal profiles were captured and validated using infrared thermography against SolidWorks simulations. Experimental data revealed maximum weld pool temperatures of 528 °C and sharp thermal gradients in the heat-affected zone (HAZ). The numerical model, which predicts a peak temperature of 670°C, closely matched the experimental results. An empirical relationship between welding parameters and maximum welding temperature was derived, allowing optimization of heat input and welding speed to minimize thermal distortions and residual stresses. This integrated approach improves process control and weld quality in shipbuilding.

Abstract: Inland waterway shipbuilding plays a pivotal role in facilitating the transportation of goods and passengers in numerous regions worldwide. To meet the ever-evolving demands of efficiency, safety, and sustainability, shipbuilders constantly seek to enhance the quality and performance of their vessels. Welding, a critical component of shipbuilding, has garnered significant attention due to its potential to introduce deformations and residual stresses, which can adversely affect structural integrity and long-term performance. This study presents preliminary research aimed at comprehensively understanding the influence of deformations and residual stresses after the welding process in inland waterway shipbuilding. The preliminary findings of this research highlight the significant influence of welding parameters, material properties, and welding sequences on the magnitude and distribution of deformations and residual stresses in inland waterway shipbuilding. These findings have implications for ship design, fabrication, and inspection procedures. By mitigating deformation and residual stress-related issues, shipbuilders can enhance the structural integrity, safety, and operational efficiency of their vessels.

Abstract: The structural integrity and safety of the vessels depends significantly on the quality of their welded joints, particularly at specific nodes where high-stress concentrations are common. This research leverages computer-aided design, artificial intelligence and materials science advancements to develop an innovative software tool that integrates expert knowledge, and best practices, for inland vessel welding. The proposed expert software system offers several key features, including the visualization of specific ship nodes, their parameters, as well as the residual stresses and strains that are specific to each node. By integrating these functionalities, the software aims to minimize human error, reduce inspection time, and ultimately improve the overall structural reliability of inland vessels.

Abstract: A large vessel, such as a container ship or an oil tanker, requires painting processes that include not only application, but also cleaning, substrate preparation and corrosion treatment. Moreover, these processes take place during construction (both in the construction of blocks in the workshop and in the assembly at the dock) and also during the operation phase of its life cycle, as part of its maintenance. This research analyzes the advantages of the implementation of key enabling technologies in painting processes versus the proposal of preventive measures, collective and individual protection, and training of workers in traditional manual processes. Using the Fine-Kinney method, which assesses potential hazards and associated risks, the degree of danger of the different tasks present in the current painting processes of large vessels is measured. These risk scores is compared with those of the new activities resulting from the simulation and automation of the associated processes, analyzing their justification by confronting their level of correctness (risk mitigation) with the cost factors of their implementation. The results show that, from a health and safety point of view, the proposal of these measures is fully justified. Therefore, it can be concluded that the inclusion of key enabling technologies in the painting processes of a ship throughout its life cycle drastically reduces risk levels, improving the safety and health conditions of the workers involved, without prejudice to an increase in the cost of services or in the delivery deadlines to the client, which confirms their reliability.

Abstract: Analysis of modern tendencies in digitalization of economics prove the increasing interest of industrial enterprises towards new digital manufacturing technologies. Industrial laser technologies are developing really fast in various branches of industry. Perspectives of hybrid laser welding industrial application particularly in shipbuilding are rather interesting. Introduction of hybrid laser arc welding in shipbuilding increases strongly economic efficiency of the production process. Each project needs preliminary assessment. Feasibility study of replacing the automatic welding equipment by modern hybrid laser arc welding technology at a shipbuilding yard shows its relevance and importance.

Abstract: Modern shipbuilding yards apply traditional aluminum alloys in production of high-speed vessels, ships with dynamic principles of support, other small vessels and vessel constructions. These alloys provide the low weight for the construction, but have definite disadvantages, which could be improved by application of the new generation Al-Sc-alloy with low concentration of scandium. The developed technology allows to increase durability and to improve other mechanical characteristics, decrease the vessels’ weight, decrease operational costs, increase the operational lifecycle of the production, as well as to achieve some indirect effects. The feasibility study was held to assess the economic effect of applying the new generation Al-Sc-alloy in shipbuilding, which proves its advantages comparing to traditionally used Al-alloys.

Abstract: Shipbuilding as a megaproject has many uncertainties due to the overlapping design and construction activity. It is primarily driven by the substantial time and complexity involved in designing a ship and by the irregular pattern of demand from ship-owners. However, in shipbuilding operations nowadays, the role of other stakeholders has become increasingly relevant to address these issues and to improve firm's knowledge. This study argues that a characteristic of a successful shipbuilding project lies in the internal and external learning process which runs in parallel to all operations. Focusing on the small sample of firms, this paper will identify the process of routine, changes, and adaptation that is been practised and implemented across shipyards to produce a higher value product and service.

Abstract: The results of corrosion properties research of aluminum alloy AW 7020 (AlZn5Mg1) welded by friction stir welding (FSW) and MIG were presented. Friction Stir Welding (FSW) – a new technology can be successfully used for butt welding of different types of aluminum alloy sheets. In the paper, the parameters for friction stir welding of sheets made of AlZn5Mg1 [7020] alloy were presented as well as parameters for MIG. Metallographic analysis of bonds showed a proper structural construction of both, the FSW and MIG welded 7020 aluminum alloys.The study was carried out in accordance with the requirements of the ASTM G 106. EIS measurement was performed in three-electrode system in artificial seawater (3.5% NaCl). Impedance studies were carried out at the corrosion potential. Changed voltage signal amplitude in the range ±10 mV and frequency range of changes was as follows: 100 kHz – 0.1 Hz. Atlas 0531 EU & IA potentiostat was used for studies.The results of electrochemical impedance spectroscopy are presented in the form of parameters characterizing the corrosion process. Obtained results were statistically analyzed.The electrochemical impedance spectroscopy studies have shown that the joint welded by FSW has better electrochemical corrosion resistance than the joint welded by MIG and the native material – AW-7020 alloy.Original value are received results of the corrosion properties of new method friction stir welded AlZn5Mg1 alloy compared with traditional MIG method and the native material.

Abstract: The paper presents the research results on the mechanical properties of aluminum alloy 7020 and its FSW and MIG welded joints. For comparison, alloy 5083 – the most currently used in shipbuilding alloy was chosen as well as 5059 – the new high-strength alloy. Besides, the native material alloys there were investigated their joints welded by FSW and MIG – the same methods as alloy 7020. Welding parameters used for the connection of the sheets made of 7020, 5083 and 5059 alloys were presented. Metallographic analysis showed the correct construction of structural bonded joints.Friction Stir Welding (FSW) – a new technology can be successfully used for butt welding of different types of aluminum alloy sheets. FSW method can be an alternative to traditional arc welding methods, especially MIG, which is the most common method of joining aluminum alloys used in shipbuilding. The research was carried out using a static tensile test in accordance with the requirements of the Polish Standards PN-EN ISO 4136:2011 and PN-EN ISO 6892-1:2010. Flat samples cut perpendicular to the direction of rolling were used. The research was conducted at the temperature of +20 oC.Friction stir welded joints of tested alloys have higher strength properties as compared to MIG welded joints. The 7020 alloy has higher strength properties then alloys 5083 and 5059. The yield stress is higher by 14.8% as compared to alloy 5083, and by 11.7% as compared to the alloy 5059. Plastic properties of alloy 7020 are the lowest, but with reserves meet the requirements of classification societies. The joints welded by FSW of alloy 7020 have the highest strength properties of all researched joints – higher then alloys 5083 and 5059 joints welded by FSW and joints of all alloys welded by MIG.

Abstract: FSW process has been evaluated on three shipbuilding steels (DH36, S690QL and 80HLES steels) by fully penetrated butt welds on 8mm thick plates. Non destructive tests were carried out to highlight the presence of intrinsic defects known for the welding process (eg kissing bond). The validated inspection methodology (volume and surface testing) confirm the integrity of welds and the absence of geometrical defects for examinations and mechanical tests as part of a qualification procedure.