International Journal of Marine Engineering and Applications

ANALYSIS OF THE EFFECT OF THE SECOND THICKNESS LAYER OR INTERMEDIATE LAYER ON THE THREE-LAYER SYSTEM ON ADHESION STRENGTH ON CARBON STEEL SURFACE

2025-09-10T03:54:31+00:00

Generally, the marine & offshore industry uses a wide range of coatings, both liquid and thermal, which aim to protect or inhibit the rate of corrosion of materials in the surrounding environment. Referring to the Norsok M-501 standard, there is a Coating System Data Sheet (CSDS) that provides an overview of the coating system according to the surrounding environment. In CSDS 1B, a three-layer system is employed, consisting of a zinc-rich epoxy primary layer, an epoxy intermediate layer, and a UV-resistant top layer. The specification provides the thickness of each coating layer from the first layer to the top layer. However, during the fabrication process, there are some challenges that occur with the second layer, which is epoxy. Sometimes, during the application of the second layer, the thickness of this layer is less than or more than the specified thickness. This study aims to determine the effect of the thickness of the second layer (intermediate layer), namely epoxy, on the adhesion of the three-layer system. This research will be carried out through experimental testing with variations in the thickness of the second layer (intermediate coat) of 50, 100, 150, 200, and 250 microns. The adhesion test for the second layer will use the X-Cut Tape Test and Pull-Off Test methods. The results of the adhesion strength test show that the thickness of the second layer affects the adhesion value of the coating system itself; The thicker the intermediate layer, the worse the adhesion strength, or there is a decrease in adhesion strength. This is supported by the test results on panel 1 with a second layer thickness of 50 microns, which obtained an average tensile test result of 18.37 MPa, and on panel 5 with a second layer thickness of 250 microns, which obtained an average tensile test result of 14.19 MPa.

PERFORMANCE EVALUATION OF SCR (SELECTIVE CATALYTIC REDUCTION) SYSTEM REDUCING EMISSIONS IN SHIP MAIN ENGINES

2025-08-08T07:17:32+00:00

The increase in global shipping activities has led to higher emissions of nitrogen oxides (NOₓ) from ship main engines, contributing significantly to air pollution and environmental degradation. This study aims to evaluate the performance of the SCR system in reducing NOₓ emissions from a ship’s main diesel engine under various load conditions. The research employed an experimental method with quantitative analysis. Data were collected through direct measurements on a medium-speed marine diesel engine equipped with an SCR unit using urea as a reductant. Additionally, the installation of the SCR system did not significantly affect engine power output or specific fuel oil consumption (SFOC). In conclusion, the SCR system is a reliable and efficient emission control technology for marine engines to comply with IMO MARPOL Annex VI Tier III standards. Optimizing the urea injection control system is recommended to enhance long-term performance and reduce operational costs.

PREHEATING TEMPERATURE EFFECT ON FLUX-CORED ARC WELDING (FCAW) IN 3G POSITION ON STEEL PLATE TOWARDS TENSILE STRENGTH AND HARDNESS

2025-09-30T02:18:09+00:00

Every process, whether planning, testing, or production, must meet established standards and be conducted professionally. Professionalism means that processes are carried out correctly, from procedures and implementation to analysis and decision-making or conclusions. This prevents undesirable outcomes and ultimately ensures the sustainability of the company or its operations. This research was conducted to fulfill the professionalism standards in studying the effect of preheating temperature on welding results, especially on the mechanical properties of the weld, in this case, the tensile strength and hardness of LR Grade (AH36) steel plate welds. This research used the Flux-Cored Arc Welding (FCAW) process with variations in preheating temperature: without preheating, 100°C, and 200°C. The tensile test results showed that the specimen without preheating had the highest tensile strength of 530.28 MPa. Among the preheated specimens, the specimen with preheating at 200°C had the highest average tensile strength of 518.79 MPa. Therefore, it can be concluded that increasing the preheating temperature of the material decreases its tensile strength. Hardness observations showed that higher preheating temperatures caused a decrease in the hardness of the base metal and the Heat-Affected Zone (HAZ), while the hardness of the weld metal increased. Based on these two parameters, it can be concluded that preheating is not optimal for flux-cored arc welding (FCAW) with LR Grade (AH36) material.

THE EFFORTS TO IMPROVE REPAIR AND MAINTENANCE ON THE SHIP ENGINE TO OVERCOME OVER NOISE

2025-09-30T02:20:31+00:00

The noise generated by ship engines is a significant environmental issue in the maritime industry. This research aims to identify noise sources, assess their impact on human health and the environment, and develop effective strategies for improvement and maintenance. Research methods include identifying noise sources through field surveys and noise measurements, followed by data analysis to determine their impacts. Literature reviews on the basic concepts of noise in the maritime environment and previous related studies form the basis of understanding in this research. The results of this study are expected to provide valuable recommendations for reducing the impact of ship engine noise on the environment and human health. This research is expected to make a significant contribution to improving the sustainability of the maritime industry by enhancing environmental quality and worker well-being.

MATERIAL DURABILITY ANALYSIS ON FIBERGLASS SHIP CONSTRUCTION

2025-09-24T02:13:56+00:00

Industrial needs for materials that have the same properties as metals and are resistant to corrosion require the development of various types of materials, one of which is fiberglass composite. The use of fiberglass material has been widely used in the automotive, shipping, and other industries. This research aims to analyze the strength of materials on fiber ships to identify the characteristics of FRP composite materials used on fiber ships. The method used in this research is to conduct material strength testing on FRP composite samples using tensile testing techniques to predict material strength on fiber ships. The results of the study are the highest tensile strength value, namely the volume fraction of 40%, namely 198.99 Mpa and the smallest tensile strength value at a volume fraction of 20% and the effect of tensile volume on tensile strength, where the greater the percentage of the volume fraction value, the greater the tensile strength value of the composite range from 20% to 40%. The conclusion in this study is that there is an effect of tensile volume on tensile strength, where the higher the percentage of volume fraction value, the higher the tensile strength value of the composite and in the test specimen almost debonding or fiber pull out, which occurs due to the selection of the manufacturing method, namely hand lay-up which is likely to occur voids in composite specimens.

DESIGN OF THE MAIN ENGINE FOUNDATION OF SHIP X TO SUPPORT MAIN ENGINE REPOWERING

2025-10-13T06:12:59+00:00

Ship “X” is one of the motor ships built in 1974 and is of the passenger type. Repowering is planned because the current speed is deemed insufficient to meet the expected operational targets. The ship uses the previous main engine with a capacity of 4 x 1340 HP to 2 x 2600 HP. An important part of the main engine is the foundation located at the bottom, because the foundation is attached to the main engine with a large power, the foundation must effectively ensure the safety of the hull structure to withstand a wide variety of forces that can be provided by loads on the foundation. The engine foundation must be able to withstand the load on it without causing shear stress, as if the engine has become an integral part of the ship itself. Given that this will be done, a new main engine foundation design process will be made. There are two types of materials simulated, namely bki grade A and B standard steel, with two loads during operation, namely a fixed load of 29,577.15 N and a total load of 165,128.41 N. In carrying out the research, modeling and simulation were carried out with Autodesk Inventor software. So, this research produces the most efficient material, namely bki grade A steel, because it has a greater yield strength and tensile strength. The material has simulation results with minimal and maximum difference values in %, Stress XY 0.56%, Stress Z 0, 11%, Stress YY 0.11%, Stress stress and strain of Von Mises Stress 0.05%, 1st Principal Stress 0.18%, 3rd Principal Stress 0.18%, Stress XX 0.03YZ 0.02%, Stress ZZ 0.07, Equivalent Strain 0.44%, 1st Principal Strain 0.46%, 3rd Principal Strain 12.25%, Strain XX 0.02%, Strain XY 0.18%, Strain XZ 0.09, Strain YY 0.22%, Strain YZ 0.36%, Strain ZZ 0.09%.

SUSTAINABLE MARITIME HUMAN RESOURCE DEVELOPMENT STRATEGY IN SUPPORTING THE BLUE ECONOMY IN INDONESIA

2025-09-24T02:14:33+00:00

The development of maritime human resources (HR) is a key factor in realizing a sustainable blue economy in Indonesia. However, there are fundamental gaps in the form of an educational curriculum that is not fully relevant to industry needs, limited access to ongoing training, and low ownership of international certifications among the maritime workforce. This study aims to analyze the actual conditions, main obstacles, and strategies for strengthening maritime HR competencies to increase national and global competitiveness. The research method used a quantitative descriptive survey of 128 respondents, consisting of sailors, cadets, maritime vocational education lecturers, industry practitioners, and regulators in Surabaya, Makassar, and Bitung, supplemented by in-depth interviews. The results showed that 72% of respondents considered the curriculum not yet in line with the demands of the blue economy, 64% stated that ongoing technical training was still limited, and only 38% had international certification. A SWOT analysis identified priority strategies, namely strengthening the blue competency-based curriculum, on-demand training according to industry needs, vocational-industry partnerships, and digitalization of the training and certification system. In conclusion, maritime human resource development requires an integrated approach between the government, educational institutions, and industry to create an adaptive, competent, and sustainable workforce, in line with Indonesia's vision as the world's maritime axis.