Energy, Materials and Product Design is an open-access journal and published by the Department of Mechanical Engineering, Faculty of Engineering, University of Mataram, Mataram, West Nusa Tenggara, Indonesia. Energy, Materials and Product Design publishes two articles per volume every year, published in May and November. Energy, Materials and Product Design is a forum for publishing research results, case studies, and reviews related to mechanical engineering, such as energy, materials, product design, and ergonomics, which can influence other engineering fields. The scope of this journal is the field of mechanical engineering, including research or case studies related to heat exchangers, energy conversion including solar, wind, marine, biomass, heat storage, materials and components including manufacturing and metallurgy, electric vehicles or their components, as well as Ergonomics applications in tool and work station design. Articles can be written in Indonesian and English according to the Energy, Materials and Product Design journal guidelines. Energy, Materials and Product Design has been indexed in the Crossref (DOI), Google Scholar, and Digital Reference Garba (GARUDA). ISSN 2964-6987 | DOI prefix 10.29303/empd
Jurusan Teknik Mesin, Fakultas Teknik, Universitas Mataram
EVALUASI KINERJA TERMAL UNJUK KERJA KOMPOR BERBAHAN BAKAR OLI BEKAS
The use of used cooking oil and waste oil as fuel—particularly for cooking—is becoming increasingly common among the public in Indonesia. While this practice offers economic advantages, improper management of used oil can lead to environmental problems such as air and soil pollution. To address this issue, alternative methods for processing used oil are needed to minimize its negative impact. One such method is the use of a used oil stove, which utilizes waste oil as fuel. This not only reduces the amount of oil discarded but also provides a cost-effective substitute for more expensive fuels like gas or kerosene. The purpose of this study was to examine the effect of varying air flow velocities on flame temperature, flame color, and the time required to heat water using used oil as fuel in a stove. The stove was tested under different air flow conditions, and flame temperature and color were observed in three stages. Additionally, the time taken to heat water to approximately 90 °C was recorded. At the lowest air flow rate of 15 m/s, the flame temperature reached 251.5 °C, and the water heating time was 187 seconds. At the highest air flow velocity of 29 m/s, the flame temperature increased to 273.7 °C. These results indicate that higher air flow velocity lead to increased flame temperatures and improved heating efficiency, suggesting that optimizing air flow in used oil stoves can enhance their performance while supporting more sustainable fuel practices.
Copyright (c) 2025 I Made Mara, I Made Adi Sayoga, I Made Nuarsa https://creativecommons.org/licenses/by-nc/4.0
STUDY OF RENEWABLE ENERGY AND ECONOMIC IMPROVEMENT FROM UTILIZING RICE HUSK WASTE THROUGH BIOMASS CO-FIRING
Utilizing rice husk waste as a renewable energy source has significant potential to support national energy security while providing added economic value to the community. Indonesia, with rice production reaching 53.14 million tons in 2024, has a potential rice husk waste of 10.63 million tons. With an average calorific value of 14 MJ/kg, the theoretical energy potential of rice husk reaches 148.8×10⁹ MJ, equivalent to 41.33 GWh per year. The use of rice husks as a fuel mixture (co-firing) in coal-fired power plants significantly contributes to increasing the renewable energy mix and reducing greenhouse gas emissions. According to PLN data, the biomass co-firing program has been implemented in 46 PLTUs by 2023, with biomass usage reaching 1 million tons and emissions reductions of approximately 1.05 million tons of CO₂e. Rice husk co-firing trials at several coal-fired power plants, such as Jeranjang, Paiton, and Suralaya, demonstrated stable operation with high efficiency and a reduction in SO₂ emissions of up to 29.22%. Despite its lower calorific value than coal and high ash content (up to 20.67%), rice husk still has the potential to be used at a ratio of 20–30% of the energy mass. Its silica (SiO₂) content, which reaches 95.52%, poses challenges such as slagging and fouling, but the ash residue can be used as a cement mixture or silica powder. Utilizing rice husks through the direct co-firing method is considered most suitable for coal-fired power plants in Indonesia because it is inexpensive and easy to implement without significant modifications. Overall, rice husk co-firing can support the clean energy transition, reduce dependence on coal, improve the rural circular economy, and contribute to Indonesia's 2060 Net Zero Emission target.
I Gusti Agung Ketut Chatur Adhi Wirya Aryadi
Copyright (c) 2025 I Gede Bawa Susana, I Gusti Agung Ketut Chatur Adhi Wirya Aryadi https://creativecommons.org/licenses/by-nc/4.0
ANALISIS EFISIENSI ENERGI PADA PROSES PENGERINGAN GABAH MENGGUNAKAN DRYER GRAINPRO 30T-HS DI PT KARUNIA TRINITAS AGRO
Rice is a key food commodity that plays a strategic role in maintaining national food security. One of the important stages in post-harvest processing is grain drying, as excessive moisture content can reduce rice quality and accelerate deterioration during storage. This study aims to analyze energy efficiency in the grain drying process using the GrainPro 30T-HS dryer at PT Karunia Trinitas Agro. The research method was conducted through direct observation with measurements of grain moisture content, drying temperature, process duration, husk fuel consumption, and electricity usage. The results showed that grain moisture decreased from 25.1% to 12.5% with a total mass of 23,000 kg. The drying process was carried out at 60 °C for 17 hours, with husk consumption of 1,500 kg and electrical power of 19 HP. Based on the calculation, the energy efficiency of the dryer reached 34.65%, which is relatively higher compared to other studies on biomass-fired batch dryers. This finding highlights that utilizing rice husks as fuel is not only economical but also environmentally friendly, thus the GrainPro 30T-HS can be recommended as an efficient drying system for industrial-scale applications..
Copyright (c) 2025 I Wayan Joniarta, Yoga Raditya Ananda Putra, Made Wijana, I Kade Wiratama https://creativecommons.org/licenses/by-nc/4.0
CHARACTERISTICS OF VIBRATIONS IN THE FORM OF WAVEFORM AND SPECTRUM THROUGH FOURIER TRANSFORM
The analysis of machine vibration is therefore essential for predictive maintenance and condition monitoring. Modern approaches, ranging from time-domain measurements of acceleration, velocity, and displacement to frequency-domain and modal analysis. This study investigates the vibration characteristics of rotating equipment in a manufacturing environment, focusing on identifying dominant frequencies, evaluating amplitude trends, and assessing overall machine condition. Data collected from accelerometers mounted on a centrifugal pump were processed using time-domain and frequency-domain techniques. The results highlight clear signatures of imbalance and bearing wear, demonstrating the value of predictive maintenance based on vibration monitoring. As the result the amplitude–frequency spectrum demonstrates that the machine is primarily influenced by rotational imbalance, with minimal evidence of high-frequency faults.
Copyright (c) 2025 Salman, I Dewa Ketut Okariawan, Nurchayati, Arif Mulyanto, Emmy Dyah Sulistyowati https://creativecommons.org/licenses/by-nc/4.0
RISK IDENTIFICATION AND MITIGATION STRATEGIES FOR WORKERS IN VEHICLE WASHING OPERATIONS
This study identifies and evaluates occupational health and safety risks faced by workers in vehicle washing operations in Mataram, Nusa Tenggara Barat, focusing on motorcycle and car wash services. Through observational studies conducted on April 6, 2025, key hazards were identified, including musculoskeletal disorders (MSDs) from non-ergonomic postures, chemical exposure from soap, slipping on wet floors, and noise from compressors. The Rapid Entire Body Assessment (REBA) method revealed high ergonomic risks, with REBA scores of 10 for both motorcycle and car wash workers, indicating a significant risk of MSDs due to prolonged bending and repetitive motions. Bowtie Analysis further mapped causes, consequences, and control measures, emphasizing non-ergonomic postures and chemical hazards as primary concerns. Preventive strategies, such as ergonomic training, long-handled tools, and personal protective equipment (PPE), were proposed to mitigate risks. The findings align with global studies reporting high MSD prevalence among sanitation workers, underscoring the need for ergonomic interventions and safety protocols. This study contributes to the literature by offering tailored risk mitigation strategies for the vehicle washing industry, advocating for enhanced worker safety, improved productivity, and reduced occupational health risks through comprehensive risk management and ergonomic solutions..
Copyright (c) 2025 Fikrihadi Kurnia, Cinta Mugia Wening Galih, Ade Febrian https://creativecommons.org/licenses/by-nc/4.0
ANALISIS POTENSI BIOMASSA SEKAM PADI DI PULAU LOMBOK, INDONESIA SEBAGAI SUMBER ENERGI TERBARUKAN
The utilization of renewable energy is one of the strategic solutions for overcoming dependence on fossil fuels and supporting sustainable development. This study aims to analyze the potential of rice husk biomass on the island of Lombok as an environmentally friendly renewable energy source. The methods used include collecting secondary data on rice production, estimating rice husk production as agricultural waste, and projecting the potential energy to produce. The analysis was carried out through theoretical calculations of the potential energy of rice husk biomass. It did not include economic aspects, and the collection of raw materials was not considered. The study results show that the island of Lombok has a reasonably enormous potential for rice husk biomass, with an energy value that can be converted into electricity or alternative fuels. In addition, the use of rice husk as biomass can also reduce greenhouse gas emissions and provide a positive economic impact on local communities. However, optimizing this potential requires the support of appropriate technology, infrastructure, and policies. Thus, rice husk on the island of Lombok has the prospect of being one of the promising renewable energy sources within the framework of the national energy transition.
Copyright (c) 2025 I Gede Bawa Susana, I Ketut Perdana Putra, I Gusti Agung Ketut Chatur Adhi Wirya Aryadi https://creativecommons.org/licenses/by-nc/4.0
PENGARUH VARIASI BENTUK BRIKET ARANG BIOMASSA BERBAHAN LIMBAH KAYU TERHADAP NILAI KALOR DAN BOILING TIME
Most Indonesian people currently use energy derived from fossil fuels, such as fuel oil, gas and coal. The impact of using fossil fuels is that it can damage the environment. Several alternative energy sources that are commonly developed are biomass energy. This biomass is usually processed into biochar which is a fuel with a high calorific value and can be used in everyday life. Briquettes are an energy source derived from biomass which can be used as alternative energy. In this study, briquettes were made from teak, acacia and mahogany wood waste. The method used is an experiment with the carbonization process using a modified composing drum. The independent variables used were briquette materials from teak, acacia and mahogany wood waste, variations in the shape of cube, cylindrical and hexagonal jerry cans. Tests include analysis of water content, calorific value, and changes in temperature. The results of this study showed that the best moisture content was obtained from cylindrical teak wood waste briquettes with an average value of 3.57%. Then for the calorific value, the best results were obtained from cylindrical teak wood waste briquettes with a value of 3457.0 Kkal/kg. and for temperature changes the best results were obtained on the cube-shaped mahogany wood waste briquette specimens with an average value of 10 minutes 46 seconds.
briquette ,the calorific value, wood waste, Main findings
Copyright (c) 2025 I Wayan Joniarta, Zohimundin Usman, Made Wijana, I Kade Wiratama https://creativecommons.org/licenses/by-nc/4.0
ANALISA UNJUK KERJA SUSPENSI KENDARAAN LISTRIK UNIVERSITAS MATARAM
The university of Mataram car suspension and its control was designed to minimize the vibration produced by unwanted external inputs i.e., changes of road contours that reach the car passengers. This effort will provide the passenger with higher safety and comfort. In this study, a quarter car model with two degree of freedoms (2 DOF) was designed and developed its mathematical model. The effects of the road contour were studied and analyzed in term of overshoot and settling time that affect the main body, suspension as well as the passenger. The MATLAB Simulink model was programmed to mimic the behavior of the suspension and its response to the input which was the road contour (step function). This approach was very helpful to reduce the effort, time and money. The result shows that with implementation of the design parameters chose, the responses of the system (displacement and velocities) were satisfied the criteria of comfortable (there are no overshoot), however, the settling time was seconds that much higher than expected which will disturb the passenger comfort. This point shows that the suspension design needs further improvement with consideration of using active suspension with adequate control system.
Copyright (c) 2025 I Gusti Ngurah Ketut Yudhyadi, Pandri Pandiatmi, Emmy Dyah S., Ida Bagus Alit https://creativecommons.org/licenses/by-nc/4.0
MANAJEMEN PROYEK COLD STORAGE MANGGIS DI LINGSAR
Mangosteen is the largest export commodity in the Lingsar sub-district, West Lombok district, West Nusa Tenggara. In addition to being sold in the local market, mangosteen in the Lingsar area is also exported to foreign countries such as China, the United Arab Emirates, and countries in Europe. One of the mangosteen exporters in the West Lombok area is PT BAS which has a warehouse as well as an operational location to store and manage mangosteen to be exported. To maintain the temperature of mangosteen, PT BAS uses Cold Storage to store harvested mangosteen for storage before being packaged and exported. The distribution is useful to maintain the content in mangosteen fruit so that it does not rot because it is stored in a closed room. So that mangosteen is ready for export This aims to maintain the quality of the stored mangosteen so that it is ready for export. Therefore, for cost and time efficiency, it is important to apply the design and simulation method to Cold Storage to find out the incoming levels and the company owner can monitor in real time the condition of the mangosteen stored in it.
Copyright (c) 2025 Sujud Alfanza Jihad, Is Bunyamin Suryo, Anak Agung Alit Triadi https://creativecommons.org/licenses/by-nc/4.0
EVALUASI ALAT PENGADUK DODOL NANGKA SKALA RUMAH TANGGA BERDASARKAN PRINSIP ERGO-EKONOMI
The use of manual tools in the process of stirring jackfruit dodol tends to have an impact on high workload, fatigue, and complaints from workers. The stirring process requires a lot of energy to get perfectly cooked dodol. In addition, manual tools take a long time, and the product needs to be evenly cooked, leaving a crust on the dodol stirring pan. To overcome this, an automatic stirring tool is needed at an affordable cost. Workers' participation as users is required so that the tools used match workers' wishes. Ergo-economic applications are necessary to meet workers' desires: comfort and affordable costs. From the evaluation carried out, it was found that the automatic stirring tool only requires a little energy because a machine does the stirring. This impacts the workload, fatigue, and complaints automatically decreasing when compared to using a manual stirring tool. Economically, the use of an automatic stirring tool provides benefits for dodol entrepreneurs after the 2.4th month. This is based on the investment value of the automatic stirring machine. The ROI (Return on Investment) level is 170.216%. This stirring machine is more effective because the stirring results are more even and do not cause crust on the container. Worker performance can be improved by applying ergo-economics based on preventive measures against behaviors that can potentially cause injury in the workplace. Workers are the main asset or economic resource in the industry, and ergonomics and economics are interrelated with ergonomics, which can create better working conditions, producing a better economy.
Ergo-economics, Jackfruit Dodol, Mixing, Payback period
Copyright (c) 2024 I Gede Bawa Susana, Ida Bagus Alit https://creativecommons.org/licenses/by-nc/4.0
ANALISIS EFISIENSI POMPA SENTRIFUGAL PADA DESALINASI DENGAN PROSES REVERSE OSMOSIS
This study provides information for the desalination industry in an effort to improve the performance and efficiency of desalination systems using the reverse osmosis method. By paying attention to the factors that influence the efficiency of centrifugal pumps, the provision of clean water in areas experiencing a water crisis will be better. Reverse Osmosis (RO) is a system in desalination technology that is often used to replenish fresh water supplies. RO performance depends on the quality of sea water as the raw water source. RO works by utilizing osmotic pressure. Hydrostatic pressure which is greater than osmotic pressure is used to reverse the flow, thereby producing fresh water. RO utilizes a high-pressure pump process to flow seawater through a membrane polymer structure. In RO there is a main membrane module configuration which has two functions, namely supporting the performance of the RO membrane and providing efficient fluid management. The desalination system used at PT Perusahaan Air Indonesia America (PAIA) still uses centrifugal pumps and can produce a production capacity of 600-700 m3/day, and is still in the system upgrade stage. From the calculations that have been carried out, the pump efficiency value is 59.16%.
Copyright (c) 2024 I Wayan Joniarta, Ade Aprilian Dika, Made Wijana https://creativecommons.org/licenses/by-nc/4.0
PENGARUH PENAMBAHAN UNSUR TEMBAGA PADA PENGECORAN TEKAN BLOK SILINDER BEKAS TERHADAP NILAI IMPAK DAN KEAUSAN
The cylinder liner block is part of the cylinder block which functions as a place for the engine working process to take place. Where in this section the suction, compression, work and exhaust processes occur. Cylinder blocks have two types, some can be repaired and cannot be repaired, to utilize cylinder blocks that cannot be repaired by recycling them by casting metal with copper (Cu) with variations in the addition of 5%, 10%, 15% with a casting temperature of 1150⁰C using metal molds using the press technique method. Data collection was carried out by wear testing, impact testing, and microstructure testing. By increasing the percentage of copper (Cu) in the cylinder block casting, the highest wear was obtained with the addition of 15% Cu of 2,87×10-9 m3. The highest impact strength of 15% Cu is 0.12 Joule/mm2.
Cylinder block, casting, copper, wear and impact strength
Copyright (c) 2024 Sinarep, Agus Dwi Catur, Mujiantara Daeng Permana, Ahmad Zainuri https://creativecommons.org/licenses/by-nc/4.0
KARAKTERISASI KEKUATAN GESER DAN STRUKTUR MIKRO HASIL SPOT WELDING PELAT BAJA KARBON RENDAH
Spot welding is a joining method that utilizes thermal energy generated by the resistance of electric current. Research was conducted to determine the effect of plate thickness, current and welding time on the characteristics of spot welding results. Spot welding was performed on low carbon steel plates of 0.8 mm, 1.5 mm and 1.8 mm thickness with current (50, 60, 70, 80 amperes) and welding time (10, 15, 20 seconds). Characterization of the spot welds was done by shear test (ASTM D1002-10) and observation of macro and micro structure (ASTM E3-11) and failure surface of the specimens. From the research conducted, it is known that the average shear strength increases with decreasing plate thickness, increasing welding current and decreasing welding time. The highest average shear strength of 502,772 N/mm2 was obtained with a plate thickness of 0.8 mm, a welding current of 70 A, and a welding time of 10 seconds. For thin plates, most of the shear test specimens failed in the area of the heat affected zone, while for thick plates, most of the shear test specimens failed in the area of the nugget spot weld.
Copyright (c) 2024 Paryanto Dwi Setyawan, I Made Suniartha, Sugiman, Sinarep https://creativecommons.org/licenses/by-nc/4.0
APLIKASI ALAT BANTU ERGONOMIS PADA KERJA MANUAL BERDASARKAN KAJIAN ERGO-MECHANICAL UNTUK PETANI KECIL
Using traditional tools and manual work by small farmers in rural and developing areas is routine in processing agricultural land, especially planting plant seeds. This working model includes moderate to severe workload due to additional workload, namely sunlight when planting. In addition, work is carried out with non-ergonomic work postures, namely non-natural work postures. This causes musculoskeletal complaints to workers due to the non-harmonious tools with workers. Workers' productivity will decrease and have the potential to reduce the quality of life of small farmers themselves. To help the manual work of small farmers to create effective, comfortable, safe, healthy, efficient, and sustainable jobs, an ergo-mechanical application is needed to design work tools. This application is based on studies conducted on the design of work tools from several libraries or research results. The ergo-mechanical study is an integrated system that applies ergonomic and mechanical principles. The ergo-mechanical application produces ergonomic work tools that are comfortable to use by workers, and technical standards include material, product, and service requirements. Mechanically, the application through technical drawings, mechanical planning, and work tool materials to get a strong, lightweight, and safe work tool from hazardous substances, according to technical specifications. Technical standards are related to data sheets or specifications that describe the technical characteristics of a work tool. On the specifications of the work tool design, specifications can be added that the work tools are ergonomic. Ergonomic work tools can produce effective, comfortable, safe, healthy, and efficient work. This results from the compatibility between work tools and workers or the harmonious work tools with workers. Ergo-mechanical creates comfort in work that affects the increase in productivity and quality of life for workers.
Small farmers, Manual work, Ergonomic, Ergo-mechanical
Copyright (c) 2024 I Gede Bawa Susana, I Ketut Perdana Putra
PENGARUH VARIASI TINGGI SUDU TURBIN DARI TINGGI BASIN TERHADAP DAYA DAN EFISIENSI TURBIN VORTEX
Electrical energy is a very important need for human life in various aspects, both on a large and small scale. One of the efforts to reduce the use of fossil fuels is to use natural resources that are not limited and can be renewed. Micro Hydro Power Plant (MHP) is an alternative source of electricity for the community, one of which is a vortex turbine. The vortex turbine is one type of micro hydro turbine that utilizes a whirlpool as a blade drive. This study examines the effect of blade height variations of 25%, 30%, and 35% of the basin height on power and efficiency. The results showed that the largest turbine power at 25% blade height variation from the basin height with a discharge of 0.009 m3/s was 3.294 Watt with an efficiency of 51.10%. The largest turbine power at an angle variation of 30% of the basin height with a discharge of 0.009 m3/s is 3.364 Watt with an efficiency of 50.66%. The largest turbine power at an angle variation of 35% of the basin height with a discharge of 0.009 m3/s is 4.062 Watt with an efficiency of 62.35%. Turbine power based on two-way anova analysis shows that between variations in turbine height and flow discharge have a significant effect on the turbine power produced and turbine efficiency based on two-way anova analysis shows that between variations in turbine height and flow discharge have a significant effect on the turbine efficiency produced.
Copyright (c) 2024 Tri Rachmanto, Mirmanto, Randi Lelio
APLIKASI ERGONOMI BERDASARKAN DATA ANTROPOMETRI PEKERJA PADA DESAIN ALAT KERJA
A review of the application of ergonomics to design work tools based on worker anthropometric data is carried out to provide information on its use in the production process, especially in micro, small and medium business. This is done because most people in Indonesia still use simple tools with unnatural work postures. Unnatural work postures such as bending, squatting, twisting, exposure to the sun, etc. Unnatural work postures cause musculoskeletal complaints and fatigue which have an impact on decreasing work efficiency. Of course, this causes a decrease in productivity and quality of life for workers. From the results of a review of several studies and literature, satisfactory results were found regarding the application of ergonomics in designing work tools according to worker anthropometric data. Application of anthropometric data for the design or redesign of a work tool based on the flow of 1) determining the body that is important in the design or redesign, 2) determining the user population, 3) calculating the percentile value for each predetermined body dimension, and 4) application to the design of the tool. Ergonomics application based on information related to human factors (strengths, weaknesses, or limitations) in designing work tools that are more effective, safe, comfortable, healthy, and efficient. An ergonomic work tool can be used effectively, comfortably, safely, healthily, efficiently, and sustainably. Ergonomics application as an alternative in overcoming the problem of musculoskeletal complaints and fatigue due to unnatural work postures. Ergonomics applications improve work safety and worker health so that work productivity increases.
Ergonomics, Ergonomic, Anthropometry, Work posture, Musculoskeletal complaints
Copyright (c) 2022 Energy, Materials and Product Design (EMPD)
ANALISA SISTEM KENDALI MEKANIK UNTUK PENGEMBANGAN KENDARAAN LISTRIK AUTONOMOUS FAKULTAS TEKNIK UNRAM
Currently, the vehicles that are commonly used are vehicles with fossil fuels, but we all know that these fuels are non-renewable fuels and their availability in nature is very limited, so it is necessary to innovate to use other renewable energy sources. one of which is electrical energy. Besides that, the use of electrical energy for vehicles is currently very relevant because of its relatively high efficiency and friendly to the environment, namely no CO or CO2 gas is formed as in conventional vehicles. Indonesia has the potential to develop electric cars because there is a lot of nickel available to be processed into batteries. Thus, our country has a very large opportunity to produce electric cars. To realize this, it is deemed necessary to conduct a thorough study such as the level of comfort and safety. Thus, it is needed to conduct a study of the mechanical control system so that driving comfort and safety can be achieved. In this research, we will measure the turning radius of the vehicle at various TOE angles. The resulth of this study are the greater of TOE angle produce the higer the turning radius of the vehicle, The smallest turning radius is at a TOE angle 0 degrees which is 4.42 meters and the largest at a TOE angle 1.035 degrees which is 4.53 meters.
Control, Mechanic, electric vehicle, TOE angle
Copyright (c) 2023 I Dewa Ketut Okariawan, Syahrul, Ida Bagus Alit, I Made Nuarsa, I Made Suartika
PERANCANGAN CHASIS KENDARAAN LISTRIK UNIVERSITAS MATARAM
Chassis is the main component of the vehicle that functions to support the engine, body, suspension system, electrical system and driver. Chassis is one part of the vehicle that has an important role so careful planning is needed in its manufacture. Chassis must be strong and sturdy to support the load of the driver, electric motor and accessories. In addition, the chassis must also be light so as not to overload the work of the electric motor and be able to go through various road conditions. The vehicle body is its function to shape the vehicle and also protect the people inside. In this design, steel and aluminum materials are used, then simulated using the Autodesk Inventor software. The goal is to determine the Von Mosses stress value on the chassis design. AISI 1018 steel material with a load of 700 kg, 800 kg, and with a load of 900 kg obtained a value of 5.56. The safety factor obtained is still safe because it is above the safety factor for industrial construction design, namely 4. Aluminum 6061 material with a load of 700 kg, 800 kg and with a load of 900 kg obtained a value of 7.46. The safety factor obtained is still safe because it is above the safety factor for industrial construction design, namely 4.
Copyright (c) 2023 A.A. Alit Triadi, Tri Rachmanto, I Made Mara, I G. N. K. Yudhyadi, Nur Kaliwantoro
PENGARUH PENAMBAHAN SERAT KAIN KATUN PAKAIAN BEKAS TERHADAP KEKUATAN TEKAN DAN BENDING DARI KOMPOSIT FOAM AGENT BETON RINGAN DENGAN STRIMIN BAJA
The problem of waste is a problem that requires serious handling, especially inorganic waste, where this waste cannot be destroyed by nature in a short time. Indonesia itself does not have a special treatment for this used clothing waste. Used clothes that are still fit for use can be resold or donated to those in need, but not every second-hand clothes can be reused so that used clothes are only thrown away which can cause pollution to the surrounding environment. With the increase in the human population in the world, the needs also increase, such as the need for food, clothing and there is also an increasing need for buildings. Panels are one of the most widely used building materials, especially for insulating walls in house buildings. One type of panel is a lightweight concrete panel. The purpose of this study is to utilize used clothing waste as a part of lightweight concrete composites where the fibers of used clothing waste are utilized as reinforcement for lightweight concrete composites and to determine the effect of adding used clothing waste fibers to the compressive and bending strength of the lightweight concrete. The variations that will be used are 0%, 0.3% and 0.7% with the size of the mold for bending, which is 160 mm long, 40 mm wide, 40 mm thick. while for the compression test mold is cylindrical in shape and has a height of 300 mm and a diameter of 150 mm. The results of this study indicate that there is an increase in strength in the compressive test from not using fiber or 0% of 4.42 N/mm2 , using fiber with a variation of 0.3% of 5.47 N/mm2 and fiber with a variation of 0.7% of 6.13 N/mm2 . The bending test shows a decrease in strength from variations of 0%, 0.3%, 0.7% to 3.65 Mpa, 3.376 Mpa, 2.6 Mpa.
Copyright (c) 2023 muh. rian septiawan p septiawan p, Agus Dwi Catur, Pandri pandiatmi
ANALISIS SUDUT BELOK DAN KECEPATAN TERHADAP RADIUS BELOK MOBIL LISTRIK
As the number of cars increases, the number of accidents that occur is directly proportional to the number of accidents that occur, namely 117,949 cases and this increases by around 8.3% annually, mostly due to driver negligence and lack of vehicle stability. One important aspect in car design is the steering system which influences the response of the vehicle's steering motion to steering wheel input and has a major influence on comfort as well as safety. The purpose of this study was to determine the turning radius at various speeds and turning angles and to determine the ratio of the turning angle to the turning angle of an electric car. In the analysis phase, calculations are carried out based on slip analysis to obtain the turning radius at various speeds and turning angles, and the ratio of the turning angle to the turning angle of the electric car. At the testing stage it is carried out by determining the steer rotation angle based on the specified turning angle. The results of this study are at a speed of 30 Km/hour with a turning angle of 240 resulting in the smallest turning radius, that is, in the analysis of 5.5 m and 5.75 m of experiment and the smallest percentage of turning radius, namely the results of the analysis are 4% smaller than the experimental results. At a speed of 50 Km/hour with a turning angle of 150 produces the largest turning radius, namely, in the analysis of 9.5 m and 9 m experiments and the greatest percentage of turning radius, namely the results of the analysis are 13% smaller than the experimental results. From the results of the analysis, the ratio of the turning angle to the turning radius is 18:1.
Slip angle, Turning radius, Turning angle, Steering ratio.
Copyright (c) 2023 I Made Mara, A. A. Alit Triadi, Andrian Suci Rahmawan
ANALISA USAHA LAUNDRY (HOOP LAUNDRY) DI KOTA MATARAM DENGAN METODE BREAK EVEN POINT (BEP)
Laundry is a business in the field of clothes washing services where dirty clothes are processed until clean and ready to distributed, this business is very promising because of the high level of demand for this service. Therefore, business actors in this field, namely Hoop Laundry, to continue to develop, must be supported by maximum profits by doing profit planning to find out whether this business is profitable or not.To plan profit, a tool is needed, one of which is the determination of the break- even point. In profit planning, break even point analysis is a profit planning approach that is based on the relationship between costs and income.The results of this study, it is known that the average number of kg of laundry per month produced is 1,702.52 kg with a Fixed Cost (FC) of Rp. 25,510,500 and Variable Cost (VC) of Rp. 61,828,852.5. From the laundry price per kg (p) which is IDR 6,000 the number of kg of laundry produced to reach the Break Even Point (BEP) condition is12,984 kg of laundry with a time of 7.6 months where the total expenses (TC) are equal to the total income (TR) which is IDR 77,902,498
Laundry, Break even point, cost, revenue
ANALISA PERFORMA HEAT EXCHANGER TIPE SHELL AND TUBE PADA PROSES PENDINGINAN PELUMAS SAG MILL DI AREA GRINDING CONCENTRATOR AREA 130 PT. AMMAN MINERAL NUSA TENGGARA
In the industrial world, the use of heat exchanger has an important role in helping the production process, especially in PT. Amman Mineral Nusa Tengggara. Heat exchanger which is used in various production process installations is basically a place to exchange energy in the from of heat from one fluid source to another. In the operation of a heat exchanger on a Semi Autogenous (SAG) mill this process is called oil conditioning, namely oil conditioning involving cooling and filtration in oil to coll the lubricant on the bearing SAG mill. This shell and tube type heat exchanger greatly influences the entire set of processes, because the operation caused by mechanical or operational failure can stop the operation of the unit. In this study do a comparison between the design specifications with the results of observations in the field in the morning and evening. Observations for 5 times were then analyzed using heat transfer to determine thermal load, heat transfer rate, heat transfer coefficient, LMTD, TDC. The results of these calculations can show that the heat exchanger in the morning has better performance. This is evident from its high effectiveness in the morning. However, the heat exchanger damages the leakage of the tube resulting in the mixing of oil with water and impurities from the cooling water quality from poor water flow can cause a decrease in performance on the heat exchanger.
Heat Exchanger Heat Transfer Counter Flow,Overall Heat Transfer Coefficient
Copyright (c) 2023 I Wayan Joniarta *, Wahyudi Santosa; Made Wijana
SIFAT TEKAN DAN BENDING PANEL SANDWICH BETON RINGAN SELULAR DENGAN PENGUAT PIN BAMBU
Bamboo plants are a type of grass with hollow segments in the stems, cylindrical, hard and in each book has buds or branching eyes. This bamboo plant can grow around 1200 meters above sea level and lowlands with humidity conditions and broad soil types. This plant is often found growing wild around river banks, forests, or fields. This plant is used by the community to make matting, bamboo bridges, concrete reinforcement, and so on. Concrete is a mixture consisting of sand, gravel or crushed stone and other aggregates mixed together with a paste made from a mixture of cement and water to from a rock-like mass. Lightweight concrete is concrete with a weight of less than 1900 kg/m3. The value of compressive strength is smaller than ordinary concrete and is not good at conducting heat. The specific gravity of lightweight concrete varies greatly depending on the lightweight aggregate used. Sandwich components are a type of structural composite that has the potential to be developed. Sandwich composite is a composite composed of 3 layers consisting of a flat composite (metal sheet) as the surface skin (skin) and the core material (core) in the middle (the part between). Sandwich composite is a type of composite that is very suitable for resisting bending, impact, vibration and sound dampening. Sandwich composites are made to obtain a lightweight structure but have high stiffness and strength. Usually the selection of sandwich composites materials, the requirements are light weight, heat and corrosion resistance, and price is also considered. The purpose of this study is to utilize the addition of bamboo as a concrete reinforcement instead of steel, to create a very affordable cost and to find out how much influence the addition of bamboo pins has as a core reinforcement in sandwich composites on the compressive and bending strength of the lightweight concrete. The variation of the spacing of the bamboo pins used is 3 cm and 4 cm for the width, and 4 cm 6 cm for the length of each sandwich composite. The size the sandwich composites varies, while for compression testing it has a length of 15 cm, a width of 15 cm and a thickness of 7,5 cm. And for the bending test it has a length 40 cm, a width of 10 cm, and a thickness of 7,5 cm. The results showed that there was an increase in strength in the compressive test from those who did not use pins of 0,646 N/mm2, and those who used pins with a distance of 3 cm x 4 cm of 1,94 N/mm2 and a distance of 4 cm x 6 cm of 1,596 N/mm2. Where the longer the distance between the bamboo pins, the strength decreases. For the bending test it also shows an increase from without pins having a value of 0,43 N/mm2 to adding pins with a pin spacing of 3 cm x 4 cm having a value of 0,89 N/mm2 and experiencing a decrease in pin spacing of 4 cm x 6 cm with a value of 0,25 N/mm2.
Copyright (c) 2023 Agus Dwi Catur, Pandri Pandiatmi, Fikri Haikal
PENGARUH PROSES PACK NITRIDING TERHADAP ANGKA KEKERASAN PERMUKAAN, KEULETAN DAN STRUKTUR MIKRO PADA BAJA SS 400
The pack nitriding process is a process of increasing the surface hardness of steel by using nitrogen with the help of organic compounds as a nitrogen source in the process. The processed steel is put into a vessel which is usually made of ceramic, glass or aluminum along with a compound used as a nitrogen source. During heating,The organic compounds used in the analysis process are generally stable at temperatures up to 570 oC and removal times of 2 to 16 hours. The purpose of the pack nitriding process is to increase the surface hardness while remaining ductile inside. In this study, nitrogen was added using a pack nitriding process after which it was quenched using water. The elimination times used were 4 and 6 hours with temperature variations of 560°C, 580°C and 600°C and presenting nitrogen for the 150 gram pack nitriding process. The highest hardness value was obtained at 580 °C with a surface hardness value of 234.84 kg/mm2 with 4 hours of removal time. And the highest impact value was shown by the specimen without treatment of 158.3 Joules. The results of testing the chemical composition of the specimens without treatment and after the pack nitriding process showed that there was an increase in the nitrogen element.
Copyright (c) 2023 Sujita, Pandri Pandiatmi, Fadli Bukhari
ANALISA SISTEM ELEKTRONIK POWER STEERING UNTUK PENGEMBANGAN KENDARAAN LISTRIK FAKULTAS TEKNIK UNRAM
Recenly conventional vehicles use fossil fuels, however these fuels are non-renewable energy sources and their availability in nature is very limited. If they are explored continuously then one day they will run out, so it is very necessary to save and innovate to use these sources. Other renewable energy sources, one of which is electrical energy, where this electrical energy can be generated from various sources such as water, solar, biomass and so on. Besides that, the use of electrical energy for vehicles is currently very relevant because it is environmentally friendly, that is, it does not produce CO or CO2 gas like conventional vehicles, so this energy is known as green energy. Indonesia has the potential to produce electric cars because the availability of nickel is very abundant to be processed into batteries, as a provider or energy storage for electric cars, our country has a very big opportunity to produce electric cars. To make this happen, it is deemed necessary to carry out comprehensive studies such as power steering so that comfort and safety can be achieved. The most suitable power steering is the electric power steering (EPS) type because the energy required comes from the battery. The method applied in this research is an experimental method, by measuring torque requirements on various roads, the roads chosen are asphalt roads, block paving roads and dirt roads. Based on this data, an EPS test bench then created which was able to measure the input and output torque of the EPS and look for the power consumed by the system. Road conditions can cause differences in torque requirements, in block paving road conditions the greatest torque requirement is 2.77 Nm and the smallest occurs in asphalt road conditions at 1.62 Nm. EPS testing shows that it is only loaded up to 25% with an input torque of 1,652 Nm resulting an output torque of 3,924 Nm with an electrical power consumption of 6,31 watts.
EPS, Road Conditions, Torque Requirement, Power Consumption
Copyright (c) 2024 I Dewa Ketut Okariawan, Made Wirawan, I GD. Bawa Susana, Maharsa Pradityatama
ANALISA PENGARUH KAMPUH PENGELASAN DAN PERLAKUAN PANAS TERHADAP SIFAT MEKANIK SAMBUNGAN LAS BAJA SUP9
The development of science and technology which is growing rapidly greatly affects industries that produce machine elements that use steel as the main raw material, steel is widely used in construction. This has caused many mechanics to join steel using the SMAW process without regard to the welding method and mechanical properties which causes the steel not to be connected perfectly, thereby endangering safety. The purpose of this study was to see the effect of seam variation V, K and X and normalizing, quenching and no heat treatment on the mechanical properties of welded joints in SUP9 steel. From the variation of seam and heat treatment, there were 9 combinations with 3 repetitions. The results of this study indicate that the weld seam and heat treatment affect the tensile strength and impact price of SUP9 steel. The most optimal treatment to produce high tensile strength is seam variation X with quenching heat treatment with ASTM E8 specimen shape having an average tensile stress value of 84.23 Kgf/mm2, and for the most optimal treatment to produce high impact values is variation of seam X with normalizing heat treatment with specimen form ASTM E23 has an average impact value of 1.11 J/mm2.
seam, SMAW, Heat Treatment, SUP9, mechanical properties
Copyright (c) 2023 I Made Mara, Tri Rachmanto, Syamsul Hadi
PENGARUH VARIASI pH DAN RAGI TERHADAP VOLUME DAN KADAR BIOETANOL DARI BAHAN MOLASE
Energy is a necessity in carrying out economic activities in Indonesia, both for consumption needs and production activities in various business sectors. As a natural resource, energy must be used optimally for the benefit of society and its management must be based on the principles of sustainable development. Bioethanol is a renewable and environmentally friendly energy that can be used as an alternative to fossil fuels. The use of bioethanol as fuel has several advantages, namely the high oxygen content of bioethanol (35%) so that it can produce clean fuel. The purpose of this study was to determine the effect of variations in pH and yeast on the volume and content of bioethanol from molasses material using and the drying time used was 48 hours. From variations in pH and yeast, 9 types of treatment were obtained with 3 repetitions so that the total sample was 27. From the results of the study, the average volume of alcohol produced was at most 550.67 ml in the yeast mass treatment 10 gr/l with a pH of 4.5 and the least was in the yeast mass treatment 15 gr/l with a pH of 4.2 of 432 ml. Whereas the highest average yield was 91.67% for yeast mass of 10 gr/l with a pH of 4.2 and the lowest was found for yeast mass of 15 gr/l with a pH of 4.8 of 88.33%.
Copyright (c) 2023 Nurchayati, Sugeng Kuswanto, Tri Rachmanto
ANALISIS RISIKO KERJA PADA PROSES PEMBUBUTAN MENGGUNAKAN METODE HIRARC
Poor management of occupational safety and health (OSH) has an impact on occupational accidents. This results in losses for both the individual worker and the company. Therefore, the occupational hazard accident risk analysis was carried out using the HIRARC (Hazard Identification Risk Assessment and Risk Control) method. Data collection was conducted from the business owners of SSBC (Sanggar Sarana Baja Cakra) Welding and Turning Shop, located in Cakranegara, Mataram, West Nusa Tenggara. There are 3 work activities for risk identification, namely the clamping process, the engraving process and the drilling process. The results of the analysis show that the highest level of occupational risk occurs during clamping and engraving process. For drilling, it's in low level of risk. As for risk management, it is mainly done for high-risk level. Immediate improvement is needed by providing personal protective equipment (PPE) to workers to reduce these risks. Based on these results, business owners can do evaluation on his business so occupational accidents can be in the workplace.
Copyright (c) 2023 Fikrihadi Kurnia, Maharsa Pradityatama, I Gusti Made Bagus Sri Gunartha, I Gusti Ngurah Agung Natria Patraman, I Putu Bayu Pramartha
ANALISIS EFISIENSI BOILER CFB UNIT 3 MENGGUNAKAN METODE LANGSUNG DI PT PLN INDONESIA POWER OMU JERANJANG
A Boilers play an important role as steam power plants. A boiler is a closed vessel that is used to produce pressurized steam, where the resulting pressurized steam is used outside the boiler itself. This research aims to find out how to analyze the efficiency of CFB boilers. The analytical method used is the direct method. The results obtained show that the efficiency value of CFB boiler unit 3 of PLTU Jeranjang with a load of 25.8 MW, namely 73.17%, is quite low, this is caused by a lack of steam flow as a result of a leak in the upper boiler of PLTU Jeranjang unit 3, causing steam to come out of boiler and reduces its efficiency.
Copyright (c) 2024 I Wayan Joniarta, Rashid Ridho Al Buhori, Made Wijana
PENGARUH KEKUATAN IMPAK DAN TARIK KOMPOSIT BERPENGUAT SERAT SEMBUKAN DENGAN MATRIK EPOXY
Composite is a combination of two or more elements arranged in a certain way to get new properties in matrial. Plants of Pukan (Peaderiafoetida L.) is a kind of wild grass that spreads and grows wild in nature. This study aims to determine the effect of the mechanical strength of the composite reinforced dying in the Healing with epoxy matrix. In this test, using Sembukan fiber as a reinforcement and epoxy as a composite matrial adhesive. The tests include: Tensile tests referring to ASTMD 3039, and Impact Tests referring to ASTMD 256. These tests use fiber volume fractions of 20%, 30%, and 40% with woven fiber orientation. The results showed, the greater the fiber volume fraction, the greater the toughness, the highest toughness was found in the fiber volume fraction variance of 40%, amounting to 0.10396 J/mm2. Same as Tensile testing, the stress increases with increasing fiber volume fraction, ie at 40% fiber at 9,1596 MPa. The influencing factor is none other than the percentage of fibers in the composite increasing the mechanical strength of the matrix. Keywords: Fiber Heal, toughness Impact, Tensile strength.
Fiber Heal, toughness Impact, Tensile strength.