Kaizen implementation to reduce dimensional defect in the welding process of Fender D155A-6R at PT Arkha Jayanti Persada

Kaizen is a concept of continuous improvement that emphasizes quality enhancement and efficiency in production processes. In this study, the Kaizen approach was applied to address dimensional defects in the welding process of the Fender D155A-6R component at PT. Arkha Jayanti Persada. The component, which was previously imported from Japan, is currently being tested through local production trials. Initial inspection indicated that 11 of 33 measurement points were out of tolerance, most of which were linked to welding activities. To analyze the problem, the PDCA (Plan, Do, Check, Act) cycle was employed. The investigation revealed several contributing factors: the absence of a locator to secure parts during welding, insufficient reinforcement that caused deformation, and the lack of a standardized welding procedure for operators. Corrective measures were then introduced, including the installation of a locator, additional reinforcements, and the establishment of a formal welding procedure. After two PDCA cycles, the dimensional issues were successfully resolved. The findings indicate that applying Kaizen through PDCA led to significant improvements in dimensional accuracy and product quality

The effect of variations in vulcan concentration in agel-cotton rope as a reinforcement for ripoxy composites on thermal conductivity properties

Ripoxy composites reinforced with natural agel-cotton rope reinforcement have attracted attention in engineering material applications due to their mechanical properties and environmentally friendly waste. Vulcan chemicals, which are fillers or additives in the composite manufacturing industry, are believed to be able to improve the thermal properties of the composite. This study aims to examine the effect of vulcan chemical treatment on thermal conductivity in ripoxy composites reinforced with cotton rope. This test was carried out by soaking agel-cotton rope textiles in Vulcan solution for 1 hour with variations in solution concentration: 0%, 25%, and 50%. The printing of test specimens was carried out using a Vacuum Infusion printing tool, so that the printed specimen results were not contaminated by outside air. Thermal conductivity tests were carried out using the ASTM - D5470 standard. The test results that have been obtained, the 25% concentration variation has the smallest thermal conductivity value, with a value of 0.064 W / m°C at a temperature of 100° C and 0.171 W / m°C at a temperature of 200°C. Meanwhile, with a concentration variation of 50% the value increases because the greater the concentration of Vulcan given, the density of the composite material will increase, and higher concentrations can reduce the number of pores or voids in the composite which can usually inhibit heat flow

The effect cooling media in pack carburizing quenching on the corrosion resistance of ASTM A36 steel

Rotary plow on hand tractor functions as a tool to plow the land efficiently in agricultural mechanization. This tool is made of ASTM A36 steel which functions to cut, chop, and turn the soil, thus improving the soil structure and preparing the land for planting. The disadvantages of ASTM A36 steel are low  impact toughness and corrosion resistance. In this study, ASTM A36 steel was pack carburizing quenching, with variations in cooling media in the form of water, coconut oil , and SAE 40 oil. The results of the studythe use of coconut oil as a cooling medium in the pack carburizing quenching process of ASTM A36 steel cause lower corrosion rates, slower cooling rates so that energy and impact toughness are higher compared to water as a cooling media So that coconut oil as a cooling media can be applied to the pack carburizing quenching rotary plow process to increase corrosion resistance

Drying time and mixture composition effect on biomass of pine cone and palm shell

According to the International Energy Agency (IEA), global energy demand is expected to rise by 45% by 2030, with around 80% still met by fossil fuels. This necessitates urgent development of alternative energy sources, such as biomass, which is renewable and can help reduce organic waste. This study examines the impact of varying drying times and mixture compositions of palm shells and pine fruits on the characteristics of briquettes. These materials were chosen due to their availability and potential to mitigate environmental impacts.The research investigates the moisture content, calorific value, and ash content of the briquettes. Results show all briquette compositions meet the Indonesian National Standard (SNI) No. 1683:2021 for moisture content, though only WP3 fails to meet standards. Ash content for all variations exceeded the SNI threshold (≥ 10%). However, all met the calorific value standard, with WP3 achieving the highest value (6643.18 cal/g). ANOVA analysis indicates both mixture composition and drying time significantly affect moisture and ash content, but only drying time significantly impacts calorific valu

Advancements in PET bottle plastic slitting devices for raw material 3D printing filament production

The world is facing a significant environmental challenge due to the accumulation of plastic waste, especially PET (Polyethylene Terephthalate) bottles. Indonesia is no exception to this problem. Every year, millions of tons of PET bottles are produced, and most of them end up as waste that takes a long time to decompose. This study aims to investigate the technical and engineering aspects involved in creating a slitting device for PET bottle plastic, which will be used as raw material for Fused Deposition 3D printer filament. The research will focus on overcoming the challenges associated with producing consistent and high-quality raw materials filament and exploring innovative solutions and advancements in filament material design. The slitting device is designed to produce plastic strips with a consistent width of 10 mm and a tolerance of ±1 mm, using easily accessible cutting blades. Ensuring a consistent strip width is crucial for producing 3D printing raw material filament with a diameter of 1.75 mm and a tolerance of ±0.05 mm. Two versions of the slitting design, version 1 and version 2, were tested, and improvements were made to reduce friction and optimize cutting efficiency, resulting in consistent strip width. The second version performed better, producing longer, more uniform strips with lower pulling force. These strips are then proposed to be processed for 3D printing filament, demonstrating the potential of this tool to transform PET bottle waste into valuable raw material

Effect of variations in the hitting point on the blade on performance of overshot water turbine

Water turbine is very important technology in producing electrical energy from renewable energy sources. Overshot turbine utilize specific gravity of water hit the blade and converts the potential energy of water into kinetic energy when the nozzle sprays water that hits the bucket and then passes it on to the transmission system becomes mechanical energy. This mechanical energy is converted into electrical energy by the generator. This research was carried out experimentally using five curved blades and an overshot turbine. The hitting point on blade distances are 0.13 m, 0.15 m, 0.17 m, 0.19 m, and 0.21 m and varying load, is 0.1 kg - 1.3 kg with constant discharge and head. The results obtained show that variations in hitting point on blades influence turbine power and turbine efficiency. The highest turbine power and efficiency for discharge of 0.0009 m3/s was obtained at hitting point of 0.13 m with load of 1 kg which produces 3.7888 watts of  turbine power and efficiency is 25.05 %

Characterization of nanocellulose from banana stem fiber and its bionanocomposite as a thermal insulation material

Nanocellulose has garnered significant attention due to its unique properties and potential in various applications, including thermal insulation. The abundant banana stems found in Lombok Island generate considerable waste that can be utilized as a raw material for nanocellulose. This research aims to characterization of nanocellulose derived from Kepok banana stems and its composites as thermal insulation in solar panels. Nanocellulose was produced using acid hydrolysis with sulfuric acid (H2SO4), and several treatments were carried out including Natrium hydroxide (NaOH), Sodium chlorite (NaClO2), Sulfuric acid (H­2SO4), The results show that nanocellulose from banana stems has a tensile strength of 13.374 MPa - 13.63 MPa. The addition of nanocellulose was found to increase the tensile strength of the composite reaching 13.374 up to 13.63 MPa, thermal conductivity 0,1692 up to 0,1940 W/mK and is quite heat resistant at a temperature of 200 °C. SEM photos of nanocellulose show surface roughness and produce interface strength between banana stem fiber nanocellulose and polyester resin. With solid bonding, good tensile strength, conductivity and thermal stability, bionancomposites from banana stem can be used as thermal insulator (backsheet) materials for solar panels

The effect of fins on PCM containers on solar panel cooling performance

Solar energy is a renewable energy source that is abundant and emits low emissions. The operating temperature of a solar panel has a significant impact on its efficiency. A 50 Wp polycrystalline solar panel was tested in this experiment using PCM (paraffin) as a passive cooling solution and without it. The PCM was placed on the backplate of the solar panel using a container equipped with fins to enhance cooling efficiency. Simulations were conducted using a solar simulator with varying light intensities of 470 W/m², 650 W/m², 900 W/m², and 1000 W/m², while a blower was used to simulate constant airflow around the surrounding area.Evaluating the panel temperature and calculating the error rate in experimental findings were the goals of the simulation. According to the simulation, the average temperature of a solar panel without cooling reached 59.4°C at an intensity of 1000 W/m2, but the temperature dropped to 57.8°C and 55.4°C, respectively, when PCM cooling with 5 and 10 fins was used.This experiment demonstrated that the application of PCM with a modified container can lower the maximum temperature of the solar panel and increase its maximum efficiency by 1.15% at an intensity of 1000 W/m². This passive cooling system has proven to be effective in reducing the operational temperature of solar panels

Oil based variation impact on fuel consumption of four-stroke 125 cc engine

Oil is one of the crucial components in the lubrication system of four-stroke engines, particularly in motorcycles. Generally, engine oil is categorized into mineral oil, semi-synthetic oil, and fully-synthetic oil. The purpose of this research is to examine the effect of different base oil types on fuel consumption. The research was conducted using an experimental method, with the independent variable being the type of base oil: mineral oil, semi-synthetic oil, and fully-synthetic oil. The dependent variable of this research is fuel consumption. A four-stroke engine with a 125 cc carburetor was used as the test engine. Each test was conducted in five times at an engine speed 2000 rpm. Data analysis was performed using repeated measures ANOVA. The results showed that the use of different base oil types had a significant effect on fuel consumption. The average of fuel consumption was approximately 9.4 mL/min for mineral oil, 8.2 mL/min for semi-synthetic oil, and 6.9 mL/min for fully-synthetic oil. It can be concluded, that fully-synthetic oil results in the lowest or the most efficient fuel consumption compared to both mineral and semi-synthetic oils

Effect of inlet air velocities on freshwater mass and heat transfer rates in an air-water harvester 0.5 PK

During the dry season, some regions experience a shortage of clean water due to drought. Air water harvesters utilize the principle of condensation to produce clean freshwater from humid air can be alternative to solve the drought. This device works by condensing water vapour in the air using an evaporator. The focus of this study was on the effect of air velocities on the freshwater production and heat transfer rates. This research was conducted experimentally using refrigerant R134a as the working fluid. The compressor used was a 0.5 HP rotary compressor. The inlet air velocities applied were 0 m/s, 1.5 m/s, and 3 m/s. The results showed that the highest average mass of water obtained was 3.73 kg using the air velocity variation of 3 m/s. Meanwhile, the total heat flow absorbed by the evaporator from the air was highest also at the air velocity variation of 3 m/s, which was 1238.22 W. Increasing inlet air velocities raises the freshwater production and heat transfer rates