IRA Jurnal Teknik Mesin dan Aplikasinya (IRAJTMA)

The Effect of Cutting Speed on The Surface Roughness of AISI 1018 Steel in the Dry Turning Process

2025-05-11T09:45:02+07:00

Cutting speed is one of the crucial parameters in the turning process that significantly affects the final quality of the workpiece surface. This study aims to evaluate the impact of cutting speed variations on the surface roughness level of AISI 1018 steel. The machining process was carried out using a chisel with a tip radius of 1.2mm, and the cutting speed was varied at three levels, namely 42m/min, 66m/min, and 105m/min. Surface roughness measurements were carried out using a Surface Roughness Tester. The experimental results showed that increasing cutting speed tended to decrease surface roughness. The lowest roughness value of 2.224 μm was obtained at a cutting speed of 105 m/min. This phenomenon occurs because at higher cutting speeds, cutting forces and vibrations are reduced, so that the machining process becomes more stable and produces better surface quality. This study shows that cutting parameters play an important role in optimizing the final results of conventional turning processes.

The Effect of Carbide Tool Nose Radius Variation on Surface Roughness of AISI 4140 Steel in the Turning Process

2025-06-17T10:22:56+07:00

The turning process is one of the machining methods used to produce cylindrical material shapes. In this experiment, meticulous parameter variations were carried out to obtain optimal surface roughness values. The parameters that varied include the chisel angle and feed rate. The feed rates used were precisely set at 0.045 mm/rev, 0.05 mm/rev, and 0.056 mm/rev. The variations in the chisel angle used were 0.4 mm, 0.8 mm, and 1.2 mm, ensuring a comprehensive exploration of the parameter space. Meanwhile, the spindle speed was kept constant at 1120 rpm, and the cutting depth was set at 0.2 mm. After testing, the surface roughness values were obtained for each parameter variation. The lowest roughness value of 0.782 µm was obtained at a combination of a chisel angle of 0.4 mm and a feed rate of 0.045 mm/rev. This finding has practical implications, as it suggests a specific parameter combination that can be used to achieve optimal surface roughness. Meanwhile, the highest roughness value of 2.206 µm was found in the combination of a chisel angle of 1.2 mm and a feed rate of 0.045 mm/rev. From these results, it can be concluded that the parameters that produce the most optimal surface roughness are in the variation of a chisel angle of 0.4 mm and a feed rate of 0.045 mm/rev, with a roughness value of 0.782 µm.

Analysis of Dual Combustion of Natural Gas and Biodiesel Fuels in a Single Cylinder Diesel Engine: Thermal Efficiency and Performance Study

2025-06-22T10:53:04+07:00

This research discussion aims to determine the performance of the Jiandong 170F single-cylinder Diesel engine when operating on dual-fuel combustion, utilizing biodiesel as the primary fuel and natural gas. In this study, RCCI and low-temperature combustion (LTC) are methods of fuel mixing by using a mixture of B30 biodiesel fuel and natural gas. The characteristic of natural gas with a low cetane number causes the combustion process to occur at lower temperatures, resulting in early ignition of the upper dead point. This condition can be examined using the HCCI method. The test results showed a 4% increase in actual torque, worth 5.8 Nm, compared to the use of pure biodiesel. In addition, there is an increase in thermal efficiency of 5-10%, which is worth an average of 30%. This makes combustion more perfect, so that it contributes to a reduction in residual emissions or NOx.

Designing Key Logistics Performance Indicators Using a Balanced Scorecard Approach

2025-07-16T23:16:54+07:00

This study aims to design a logistics performance measurement system at PT. XYZ is using the BSC approach combined with KPIs. The company operates in the field of steam turbine maintenance and repair services for the palm oil industry, but does not yet have a structured logistics performance evaluation system. The study was conducted for six months through interviews, observations, questionnaires, and documentation studies. The evaluation covered four BSC perspectives: financial, customer, internal processes, and learning and growth, with KPI analysis for each perspective. The results show that logistics performance fluctuates, especially in the aspects of customer satisfaction and employee training. A relationship was found between the perspectives, namely that decreased training has an impact on increasing delivery errors. The BSC and KPI approach has been proven to provide a comprehensive picture of logistics performance and is relevant to support strategic management. Recommendations include strategy integration, strengthening training, and improving service quality for sustainable efficiency.

Design and Implementation of a Solar-Powered Automatic Control System for an Oil Spinner Machine

2025-07-04T21:51:03+07:00

Improving efficiency and sustainability in industrial processes is a key focus in modern technological development. This study aims to design an automatic control system for an oil spinner machine using renewable energy from solar panels. The system is intended to enhance operational efficiency, reduce reliance on conventional energy sources, and support environmentally friendly initiatives. It integrates sensors to monitor machine conditions such as speed and raw material levels, with a microcontroller unit connected to solar panels as an alternative energy source. The methodology includes system design, microcontroller programming, solar panel installation, and operational testing. Results show that the system successfully improved machine efficiency, reduced consumption of non-renewable energy, and contributed to lowering carbon emissions. This research provides a significant contribution to the development of renewable energy-based automation systems. It opens opportunities for similar applications in other industrial processes requiring efficient and eco-friendly solutions.

Development of Excel VBA-Based Simulation Software for Steam Power Plant (PLTU) for Engineering Applications

2025-07-04T21:45:28+07:00

Coal-fired steam power plants (PLTU) remain essential in electricity generation, especially in countries with abundant coal resources. Thermodynamic modeling based on the Rankine cycle is crucial for both educational and design purposes, but commercial software is often costly and less accessible. This study develops a low-cost simulation tool using Microsoft Excel and VBA to model the Rankine cycle in PLTU systems. Users can input operating parameters, calculate thermodynamic properties using IAPWS-IF97 formulations, and evaluate system efficiency through energy balance analysis. The user-friendly interface features real-time efficiency graphs and energy flow diagrams. Validation results show deviations of less than 5% for key parameters, making this tool effective for engineering education, preliminary feasibility studies, and local research in thermal power generation.

Case Study: Optimization of Piping System With Type V Expansion Bend

2025-07-17T10:39:47+07:00

Industrial piping systems that transport high-temperature fluids are susceptible to thermal expansion, which can cause excessive axial stress and structural failure risks. This study aims to optimize the V-Type expansion bend design to enhance material efficiency while ensuring stress levels remain within the allowable limits set by ASME B31.3. Simulations were conducted using CAESAR II software version 2014, incorporating real project data on pipe geometry, materials, and operating conditions. The results indicate that the V-Type expansion bend requires the shortest total pipe length-5452 mm-while producing a thermal stress ratio of 30%, outperforming the U-Type bends by Thermacor (6069 mm, 20.8%) and Bahaa (10000 mm, 15.8%). The V-type configuration also results in lower nozzle loads and moments, making it a safer and more cost-effective solution for field implementation.

The Effect of Inclination Angle and Nozzle Temperature on Surface Roughness of Overhang Parts in 3D Printed PLA Material

2025-07-20T22:08:06+07:00

This study aims to investigate the influence of overhang inclination angle and nozzle temperature on the surface roughness of the overhang section in a 3D printed object using Polylactic Acid (PLA) material with the Fused Deposition Modeling (FDM) method. An experimental approach was employed by varying the overhang angles (35˚, 45˚, and 55˚) and nozzle temperatures (210˚C, 220˚C, and 230˚C) during the printing process. Surface roughness measurements were performed on unsupported overhang areas using a surface roughness tester. The results showed that surface roughness increased with greater overhang angles and higher nozzle temperatures. The lowest surface roughness value was recorded at 210˚C with a 35˚ overhang angle, while the highest was observed at 230˚C with a 55˚ overhang angle. These findings indicate that controlling the nozzle temperature and overhang angle is crucial for achieving optimal surface quality in overhang printing. This study is expected to contribute to the optimization of FDM process parameters to produce smoother surfaces.

Analysis of the Characteristics of AISI 8620 Camshaft Material and Grey Cast Iron Using Metallographic and Optical Spectrometry Methods

2025-07-31T19:43:21+07:00

The demand for non-OEM camshafts is increasing, but this raises concerns about material quality. This study analyses the material characteristics of AISI 8620 and grey cast iron camshafts used in 125cc automatic motorcycles. Testing was conducted using Metallography and Optical Emission Spectrometry. AISI 8620 exhibits a fine ferrite-pearlite microstructure and alloying elements such as chromium and molybdenum, which support heat treatment. Cast iron exhibits a pearlite structure with flake graphite, providing superior damping but less toughness. The results indicate that AISI 8620 is more suitable for high-load applications, while cast iron is suitable for lightweight and cost-effective applications. This study provides important insights into material selection for motorcycle camshaft manufacturing.