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Management of household waste in Final Disposal Sites (TPA) faces a serious problem, where most of the waste accumulates and is difficult to decompose due to its complex nature. This condition substantially inhibits natural decomposition processes and limits the effectiveness of recycling efforts. Pre-processing operations, such as sorting and crushing, which are still dominated by manual methods, are proven to be inefficient, high-risk, and require large allocations of land resources and manpower. Therefore, automated technological innovation is needed to facilitate the efficient separation of organic components from inorganic materials (packaging). This research was conducted to determine the design and structural strength analysis of a hammer mill type depackaging machine, carried out using Solidworks software. Structural analysis simulation utilizes Finite Element Analysis (FEA) to determine the structural strength of the machine. The specifications of the hammer mill type depackaging machine include a capacity of 3000 kg/hour, a hammer mill input power of 12 KW, and a rotational speed of 2500 rpm with a torque of 34.54 Nm. Meanwhile, the screw conveyor input power is 0.75 KW and the rotational speed is 20 rpm. The FEA simulation analysis results for the hammer mill type depackaging machine showed that the maximum Von Mises stress value recorded is 3,022×10^7   N⁄m^2 , the maximum displacement value measured is very minimal, namely 2,793×10^(-1)  mm, and the Factor of Safety (FOS) obtained is 8.3. This FOS value significantly exceeds the required minimum safety limit (>3), confirming that the machine design has optimal reliability, fatigue resistance, and structural integrity for operation under intensive working conditions at the TPA. The conclusion of this study indicates that the engineering design of this hammer mill type depackaging machine is safe and meets structural technical requirements to proceed to the implementation phase, potentially becoming a sustainable technological solution in improving the efficiency of waste pre-processing.

This study aims to design a blanking die used for mass-producing mobile phone holders while prioritizing efficiency and dimensional accuracy. The die set developed includes key components such as the punch, die, stripper, guide post, and fastening bolts. The product produced has dimensions of 138 × 63 × 2 mm and uses ST 37 steel as the raw material. Based on calculations, the required blanking force is 129,000 kN, which is considered safe for the production process. The design also accounts for an optimal clearance of 0.083 mm and a die thickness of 35 mm to effectively withstand the working load. Simulations using stress analysis methods reveal that the von Mises stress distribution on both the punch and die remains below the elastic limit of SKD11 material. The maximum stress on the punch is recorded at 2.437 × 10⁵ N/m², while on the die it reaches 5.153 × 10⁵ N/m², both well below the yield strength of SKD11, which is 2.918 × 10⁸ N/m², indicating that these components operate safely without the risk of plastic deformation. To strengthen the construction, the stripper is designed with a thickness of 12 mm, and the addition of four SCM435 bolts is recommended to improve system stability. This die design is verified through manual calculations and Finite Element Analysis (FEA) to ensure its reliability. Overall, the findings of this study demonstrate that the designed blanking die can support mass production with high precision, optimal structural strength, and long-term durability.

This study presents a modal analysis of Pertamina EP Cepu’s closed drain pump 510-P9002, which operates in the condensate–water treatment unit of the Jambaran Tiung Biru field. Field vibration measurements conducted in August 2024 indicated a fundamental frequency of 25 Hz, corresponding to 1×RPM of the driving motor, with maximum amplitudes reaching 13.46 mm/s. Such excessive vibration poses risks of mechanical damage, reduced equipment service life, and potential operational failure. To address this issue, finite element analysis (FEA) was employed to examine the dynamic response of the pump, determine its natural frequencies, and identify possible resonance conditions. A CAD model of the pump–vessel assembly was developed, meshed, and analyzed under actual boundary conditions. The results showed several natural frequencies ranging between 23.16 and 26.65 Hz, which are close to the excitation frequency, suggesting a very high likelihood of resonance. Various structural modifications were then evaluated, including a half casing and two types of full casings. Among these, the full casing B design provided additional stiffness in the motor support area; however, none of the modifications effectively reduced vibration within the internal components. Based on these findings, the study recommends the implementation of a dynamic vibration absorber (DVA) tuned to the excitation frequency, along with the redesign of structural components to shift natural frequencies away from operating excitation. These solutions are expected to improve operational stability, extend equipment lifespan, and enhance overall system reliability. The outcomes of this research provide important insights for managing vibration issues in pump systems operating under similar conditions, particularly in the oil and gas industry where continuous, stable operation is critical.

Organic waste management is an important issue in addressing environmental problems. One potential solution is bioconversion technology using Black Soldier Fly (BSF) maggots that can break down organic waste and produce larvae with economic value as animal feed. To increase the selling value and extend the shelf life, BSF larvae need to be dried using tools such as rotary dryers. This study aims to design and analyse the strength of a rotary dryer machine frame for maggot drying with a Finite Element Analysis (FEA) approach based on SolidWorks software. Simulations were carried out on several materials: ASTM A36, AISI 1020 Steel, and AISI 1045 Steel. The analysis results show that all materials are within safe limits based on Von Mises stress, deformation, and safety factor. AISI 1045 steel material gives the best performance with Von Mises stress of 14.238 MPa, deformation of 0.59 mm, and safety factor of 7.2. These results show that AISI 1045 steel is the most recommended material for the rotary dryer frame.

Pressure vessels are critical components in the energy industry, used to store and process high-pressure fluids. The structural reliability of these vessels plays a pivotal role in ensuring operational safety and system efficiency. This study aims to analyze the design and reliability of pressure vessels using both numerical and experimental approaches to optimize performance and enhance safety factors. The numerical method was conducted through Finite Element Analysis (FEA) using ANSYS software to evaluate stress distribution, stress concentration, and potential failure modes under various operational load scenarios. Meanwhile, the experimental method involved hydrostatic pressure testing, strain measurements using strain gauges, and displacement analysis to validate the numerical simulation results. Data were collected from simulations and laboratory experiments, then analyzed quantitatively by comparing key parameters such as stress distribution, deformation patterns, and safety factors against industry standards. The results indicate that combining numerical and experimental approaches improves the accuracy of pressure vessel behavior predictions, enables more efficient design optimization, and enhances structural reliability. In conclusion, the methods applied in this study can serve as a reference for developing safer, more efficient pressure vessel designs that comply with industrial standards, thereby supporting improved safety and operational efficiency in the energy sector.