IRA Jurnal Teknik Mesin dan Aplikasinya (IRAJTMA)

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

Sigit Setijo Budi — 2025-08-09

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.

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

Yonathan Farrel Marcelino — 2025-08-04

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

Muhammad Iqbal Gimastian — 2025-08-04

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

Resi Aji Narantoko — 2025-08-04

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

Ibnu Farras Azzikri Lubis — 2025-08-11

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

Putra Agung Dwi Yanto — 2025-08-11

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

Agus Manggala — 2025-08-11

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

Danur Riswanto — 2025-08-11

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

M. Fendy Kussuma Hadi Sufyan — 2025-08-11

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.

Experimental Analysis of the Effect of Piston Dome Height Variation on the Performance of a 4-Stroke Engine

Esa Ramdhan Ardi Mahendra — 2025-08-16

Internal combustion engines remain the primary power source in transportation by converting fossil fuel energy into mechanical energy. This study examines the effect of piston dome height variations (1 mm, 3 mm, and 5 mm) on the performance of a 4-stroke 87.70 cc engine. A quantitative method was used with a rope brake dynamometer to measure torque, adequate power, fuel consumption, and SFCe, effective at engine speeds ranging from 2000 to 5000 rpm. The highest torque and power were recorded at 4000 rpm, the highest fuel consumption at 5000 rpm, and the highest SFCe at 2000 rpm for all dome height variations. As piston dome height increases, combustion chamber volume decreases, leading to lower compression ratios and reduced combustion efficiency. Therefore, piston design should be aligned with the intended focus on either efficiency or performance.

Experimental Analysis of the Effect of Oil Type on Temperature and Fuel Consumption in a 125cc 4-Stroke Motorcycle

Fakhmi Caesar Rahmadi — 2025-08-16

This study analyzes the effect of oil type on exhaust gas temperature and fuel consumption in a 125cc 4-stroke motorcycle. Three kinds of SAE 10W-40 oil were used: mineral, semi-synthetic, and full synthetic. Tests were conducted at idle with varying rpm and while cruising at varying speeds. Temperature was measured using a thermo gun, while fuel consumption was measured using a burette. Results showed that full synthetic oil produced the most stable temperature and lowest fuel consumption, while mineral oil demonstrated the highest temperature and consumption, especially at high rpm. This efficiency is attributed to the chemical characteristics and thermal stability of the full synthetic oil. This study provides a novel contribution by testing a classic air-cooled motorcycle under static and dynamic conditions, thus better reflecting real-world use.

Experimental Analysis of the Effect of Groundstrap on Torque and Power of a 4-Stroke Motorcycle Engine

Yonas To — 2025-08-16

This study aims to analyze the effect of groundstrap installation on motorcycle torque and power. The ground strap, a copper wire coil wrapped around the ignition coil cable, functions to suppress stray frequencies, stabilizing the current flow to the spark plug for optimal combustion. The experiment involved three conditions: standard (no groundstrap), a 0.20 mm groundstrap, and a 0.18 mm groundstrap. Results showed improved performance with both groundstrap configurations. Maximum power increased from 9.16 HP (standard) to 9.30 HP (0.20 mm) and 9.33 HP (0.18 mm). Maximum torque rose from 9.76 N.m to 9.96 N.m (0.20 mm) and 10.09 N.m (0.18 mm). The most significant improvement was achieved with the 0.18 mm groundstrap, yielding an additional 0.17 HP at 7,336 RPM and 0.33 N · m at 6,000 RPM. These findings indicate that groundstrap installation positively affects ignition stability and combustion efficiency, offering a simple yet effective solution to enhance engine performance.

Maintenance Strategy Analysis to Improve Ripple Mill Machine Effectiveness Using an Equipment Effectiveness Approach

Raymond Manullang — 2025-08-16

This study aims to analyze the operational effectiveness of the Ripple Mill machine using a TPM maintenance strategy approach by measuring OEE. The method used is descriptive quantitative, with primary data from observations and interviews, and secondary data from factory operational documentation. The evaluation was based on three leading OEE indicators: availability, performance, and quality. It was complemented by an analysis of the six significant losses to identify sources of lost production time. The results show that the average OEE value from January to March 2025 reached 96.53%, exceeding the international standard of ≥85%. The most significant losses came from equipment breakdowns (69.75%), followed by minor breakdowns and idling (18.48%). Preventive maintenance programs, operator training, and spare parts availability are recommended. These results demonstrate the effectiveness of the TPM approach in continuously improving machine performance.

Strength Analysis of Blades in a Coconut Fiber Processing Machine

Ayu Audia — 2025-08-16

The design of a coconut fiber processing machine with a conveyor system requires special attention to the performance of the blade, which serves as the main component in the chopping process. Structural failure of the blade can significantly impact machine efficiency and operator safety. Therefore, modeling and structural strength analysis using computer-aided analysis software was conducted to validate the reliability of the blade design before manufacturing. The study focused on Von Mises stress, displacement, and safety factor, considering operational loads such as bending, torsion, tension, and compression applied to the shaft. The simulation results indicate that both stress and deformation remain within safe limits, with a safety factor value that supports long-term operational use. Based on these findings, the blade design is considered structurally secure and suitable for use in a coconut fiber chopping machine.

Strength Analysis of 3D Printer Results with Acrylonitrile Butadiene Styrene (ABS) Filament Based on Nozzle Temperature Variations and Infill Type

Hisyam Ma'mun — 2025-08-19

Technological advancements, including 3D printing, enable the creation of prototypes from digital designs using 3D printers. A popular method is Fused Deposition Modeling (FDM) with thermoplastic materials such as Acrylonitrile Butadiene Styrene (ABS), valued for its quality and affordability. In 3D printing, nozzle temperature and infill type influence the mechanical properties of printed objects. This study aims to determine the tensile strength of ABS with variations in nozzle temperature and infill type. Tensile test results show that a 230°C nozzle temperature produces higher yield strength for most infill types compared to 240°C. The 240°C setting tends to increase maximum tensile strength for grid and concentric infills, but not for gyroid and lines. The concentric infill type exhibited the highest elongation at both temperatures, indicating greater ductility compared to other infill types. These findings are expected to serve as a reference for optimizing printing parameters.

Rice Planning Machine Capacity Increase Based on Kinematics And Dynamics Synthesis

Samuel Tabah Penemuan Parulian Silalahi — 2025-08-20

Rice is a food crop commodity that plays a vital role in the Indonesian economy. The results of this study indicate that the designed system is capable of consistently maintaining a 25 cm spacing between seedlings through the harmonic motion of the planting arm. The angular and linear movements of the entire linkage are stable and periodic, resulting in a uniform planting process. The angular velocity of the main shaft is recorded as constant, supporting rotational stability, while the maximum motor torque is within a realistic range for field applications. The system also demonstrates good mechanical efficiency, characterized by stable kinetic energy of the rotational components and controlled motor power consumption. These findings have practical significance for practitioners and the agricultural machinery industry, as they can serve as a reference for the development of rice transplanters that are more energy efficient, highly precise, and suited to rice field conditions in Indonesia, thus potentially increasing productivity and reducing reliance on manual labor.

The Effect of Tire Tread Depth and Inflation Pressure on Braking Force

Tegar Kurniawan — 2025-08-20

This study analyzes the effect of tire tread depth and tire pressure on braking force in a Mitsubishi L300 vehicle. An experimental method was applied with variations in tread depth (>1 mm and <1 mm) and tire pressure (30 psi, 50 psi, and 60 psi). Results indicate that both variables significantly affect braking efficiency. The 50 psi–50 psi combination at >1 mm tread depth yielded the highest efficiency (86%), whereas the 30 psi–30 psi combination at <1 mm tread depth recorded the lowest (48%). A tread depth of <1 mm reduced braking efficiency by 15–20% on average. Tire pressures below or above the standard decreased braking performance by 10–15%. Maintaining balanced tire pressure at 50 psi and a minimum tread depth of 1 mm is recommended for driving safety.

Vibration Analysis on Trans Jateng Bus Corridor 4 Using MPU6050 Accelerometer Sensor and RULA Method

Muhammad Hanafi Wisnumurti — 2025-08-20

Public bus drivers are at risk of health issues due to mechanical vibrations and non-ergonomic working postures during long working hours. This study analyzed vibration levels and ergonomic risks of Trans Jateng Corridor 4 bus drivers using an experimental method with an MPU6050 accelerometer sensor at three points: brake/clutch pedal, steering wheel, and driver’s seat at various operational speeds. Ergonomic assessment was conducted using the Rapid Upper Limb Assessment (RULA) method with CATIA V5R20 software during two main work phases. Results showed the highest vibration level on the brake/clutch pedal (3.23 m/s²), still below the threshold limit of 5 m/s² for 6–8 hours of work as regulated by the Ministry of Manpower Decree No. 5/2018. The lowest vibrations were recorded on the steering wheel (0.79 m/s²) and driver’s seat (0.93 m/s²). A RULA score of 3 in both phases indicated a “low risk” category but required long-term preventive measures. Recommendations include the use of anti-vibration footwear, structured breaks every 90 minutes, and driver rotation with a maximum of 6 hours per shift to maintain optimal working conditions and prevent occupational health disorders.

Evaluation of the Effectiveness of ARTG as an Alternative to Manual RTG at the Semarang Container Terminal

Faizal Ridho Alfianto — 2025-08-20

This study evaluates the effectiveness of Automated Rubber Tyred Gantry (ARTG) as an alternative to manual RTG operations at the Semarang Container Terminal. The research focuses on productivity (boxes/hour), maintenance cost efficiency (IDR/month), and workplace safety (number of incidents). A descriptive quantitative case study was conducted from March to May 2025. Results show that ARTG improved productivity by 11.25%, reduced maintenance costs by 46.5%, and recorded zero incidents compared to four incidents with manual RTG. All differences were statistically significant (p < 0.05). These findings indicate that ARTG enhances operational efficiency and safety in port operations. Gradual implementation of ARTG is recommended, considering digital infrastructure readiness, human resource training, and policy support.

Prototype of Early Warning System for Brake Fluid Quality in Freight Transport Based on Arduino Uno

Jalu Lutfi Wijatolah — 2025-08-20

This research focuses on the development of an Arduino Uno-based early warning system to monitor brake fluid quality in freight vehicles. This system uses a TDS sensor to detect water content in brake fluid in real-time, displays the results on a 2004 IIC LCD screen, and provides visual and audio warnings if the brake fluid quality is below the safe threshold. This research employs the Research and Development method, utilizing a Planning, Production, and Evaluation model, and is validated by experts in the fields of information technology, electronics, and vehicle testing. System performance is evaluated through calibration against the Habotest Brake Fluid Liquid Tester and achieves 100% accuracy on various test samples. This prototype is proven to be easy to operate, provides accurate warnings, and has high feasibility for integration into existing vehicle fleets without requiring significant modifications. This innovation is expected to encourage a culture of preventive maintenance and improve public transportation safety.

Dry Turning Process Prototype of Air Quality Monitoring Device for Motor Vehicle Testing Unit

Ririswari Widya Wardani — 2025-08-20

This study aims to design and evaluate the performance of a prototype air quality monitoring device integrated with an exhaust fan in a vehicle testing room. The experimental method was employed to examine the relationship between variables. The increasing number of motor vehicles has an impact on air quality, particularly in emission testing areas. The device utilizes an MQ-7 sensor for gas detection and a DHT22 sensor for temperature and humidity, with data displayed in real time on an LCD screen. When the gas concentration exceeds nine ppm, the system activates an audible alarm and automatically turns on the exhaust fan to maintain air circulation. The exhaust fan expels hot air from the room while bringing in cooler outside air. Test results indicate that the device operates stably and provides accurate data, making it suitable as an air quality monitoring system in motor vehicle testing facilities.