Bookchapter Teknik Mesin

MECHANICAL AND PHYSICAL ANALYSIS OF SENGON PARTICLEBOARDS BONDED WITH MODIFIED PVAC ADHESIVES

2025-07-23T23:41:16+07:00

Wood processing waste especially sawdust is often underutilized. One effective way to optimize its use is by converting it into particleboards. This study explores the use of PVAc adhesive combined with citric acid and tapioca in producing particle boards from sengon wood particles. Three adhesive variations were tested: 40% PVAc, 20% PVAc + 20% citric acid, and 20% PVAc + 20% tapioca. Each composition used 40% adhesive and 60% air-dried wood particles by weight. The boards were hot-pressed at 160°C under a pressure of 30 kg/cm² for 10 minutes. The particleboards were evaluated based on the JIS A 5908-2003 standard for physical and mechanical properties. Physically, the boards met the standard. The highest density 0.525 g/cm³ was observed in boards with 20% PVAc + 20% tapioca, while the lowest moisture content 5.125% was found in boards with 40% PVAc. However, the mechanical properties did not meet the standard requirements. The highest Modulus of Elasticity (MOE) was 4372.776 kg/cm² in the board with 20% PVAc + 20% citric acid, and the highest Modulus of Rupture (MOR) was 66.48 kg/cm² in the board with 20% PVAc + 20% tapioca. Overall, the study shows that sengon wood particles combined with PVAc based adhesives and natural additives like citric acid and tapioca have potential as raw materials for particleboards, though improvements are needed in mechanical strength.

DESIGNING A ROTARY SYSTEM BIOMASS CHARCOAL BRIQUETTE MACHINE PROTOTYPE

2025-07-23T23:56:47+07:00

The global interest in renewable and environmentally friendly energy sources has led to the increasing utilization of biomass-based fuels, including charcoal briquettes. As one of the most abundant and high-quality raw materials in tropical regions, coconut shell charcoal presents a valuable opportunity for sustainable fuel production. However, existing briquette production technologies, particularly those using screw conveyorr systems, still face challenges in terms of production continuity and the need for manual labor during the cutting process. This study aims to design and develop a prototype of a rotary system charcoal briquette machine that integrates a screw conveyor and a cam-based pressing mechanism. The screw conveyor is designed to function both as a material feeder and compactor, feeding the biomass into a rotary die system. The cam-driven press continuously forms rectangular briquettes without requiring additional cutting mechanisms. Analytical calculations were performed to determine the screw conveyor’s capacity, power requirement, and extrusion pressure. The designed prototype achieves a production capacity of 2,65 tons per hour using a screw rotation speed of 23 rpm, a screw diameter of 98 mm, and a pitch of 43 mm. The power required to drive the screw is calculated at 0,319 kW, and the extrusion pressure reaches 60,467 Pa. The integration of rotary dies enables a semi-automatic operation that significantly reduces labor intensity and improves process efficiency. The result is a compact, cost-effective, and practical machine suitable for small to medium-scale briquette production industries, particularly those focusing on coconut shell biomass.

STRESS AND DEFORMATION ANALYSIS OF A COMPRESSION SPRING IN A ROTARY TYPE BRIQUETTE PRESS MACHINE USING FEA SIMULATION

2025-07-24T00:11:12+07:00

A comprehensive analysis of a helical compression spring subjected to static loading using two approaches: Finite Element Analysis (FEA) performed with ANSYS and manual calculations based on classical mechanical theory. The objective of this research is to compare and validate the accuracy of simulation results with manual computation, particularly in determining the force and deformation response of the spring.The spring model was first created using Computer-Aided Design (CAD) software and then imported into ANSYS in .STP format. Static structural analysis was selected as the simulation method, with meshing conducted using a body sizing of 1 mm to ensure sufficient detail while maintaining computational efficiency. The spring was modeled using appropriate material properties and subjected to axial forces simulating compression scenarios. Meanwhile, manual calculations were conducted using Hooke’s Law. The comparison between both methods revealed a percentage difference of 4.78%, which falls within the generally accepted engineering tolerance of ±5%. This suggests a strong correlation between the FEA results and manual computations, thereby validating the use of FEA for analyzing spring behavior under static loads. Furthermore, the study highlights the importance of mesh refinement and the impact of geometry setup on the accuracy of simulation outcomes.In conclusion, the findings confirm that ANSYS-based FEA can be effectively used for evaluating the mechanical performance of springs, provided that appropriate modeling, meshing, and material data are used. This approach not only enhances efficiency in analysis but also reduces potential errors associated with manual calculations, especially in complex designs or variable loading conditions.

EXPERIMENTAL STUDY OF THE EFFECT OF VARIATIONS OF TAPIOCA, PVAC AND CITRIC ACID ADHESIVES ON PHYSICAL CHANGES OF PARTICLEBOARD

2025-07-24T00:25:10+07:00

The production of wood processing produces a large amount of wood powder waste, which can be reused to make particleboards . The study aims to see how the variation in the type of adhesive affects the physical and mechanical characteristics of teak wood powder-based particleboards. The particle board made in this study has a composition consisting of 60% teak wood powder and 40% adhesive material. The adhesive used pure tapioca flour, a mix of tapioca flour and citric acid (20% each), and a mix of tapioca flour and PVAc (20% each). The boards were formed using a hot press at 160°C and 3 MPa pressure. After fabrication particleboards and making test samples with SNI standards, particleboards are tested to determine their physical properties through density and moisture content (MC) tests, as well as mechanical properties that include modulus of elasticity (MOE) and modulus of fracture (MOR). The results obtained by all samples successfully met the JIS A 5908-2003 standard in terms of density and moisture content. However, for the MOE and MOR parameters, the test scores are not in accordance with these standards. Of the three variations, it can be seen that the mixture of tapioca flour and citric acid produces the highest density, while the mixture of tapioca flour and PVAc shows the best performance in the MOR aspect. Based on these findings, it can be concluded that although all three types of adhesives are physically adequate, their mechanical strength still needs to be improved through further development.

EFFECT OF ADHESIVE VARIATIONS: TAPIOCA, PVAC, MOLASSES AND CITRIC ACID ON THE PHYSICAL PROPERTIES OF PARTICLEBOARD

2025-07-24T00:39:15+07:00

Sustainability issues and the need for environmentally friendly materials prompted the utilization of biomass waste as an alternative raw material in composite panel manufacturing. The development of biomass-based composite boards not only reduced dependence on natural wood but also provided added value to agricultural and forestry organic waste. One of the main challenges was the application of safe and effective natural adhesives to replace formaldehyde-based synthetic adhesives, which are known to be harmful to the environment and human health. This study employed three adhesive formulations: citric acid with polyvinyl acetate (PVAc/Lem Fox), citric acid with molasses, and citric acid with tapioca, to investigate their effects on the physical and mechanical properties of composite boards. The panels were produced by hot pressing at 160°C and 3 MPa, then conditioned at room temperature for five days to ensure even moisture distribution. Property tests included measurements of moisture content (MC), density, modulus of elasticity (MOE), and modulus of rupture (MOR), all following the relevant SNI standards. The results showed that variations in adhesive formulation significantly affected board strength and stiffness. The combination of citric acid and PVAc yielded the lowest MOE and MOR values at 15.14 MPa and 1.0 MPa, respectively, indicating that these panels were less stiff and more susceptible to fracture due to suboptimal interparticle bonding and high moisture content. In contrast, the citric acid and molasses formulation achieved the highest MOE and MOR values at 41.25 MPa and 2.90 MPa, respectively, followed by citric acid and tapioca at 39.78 MPa and 2.60 MPa, along with more stable density and moisture content values.

Engineering Evaluation of Pressing Temperature Effects on Mahogany Wood Particleboard Characteristics

2025-07-24T00:59:49+07:00

Particleboard is one of the products of the use of wood powder waste that can be used by the community. This study aims to analyze the effect of 140 °C, 160 °C, and 180 °C pressing temperature variations on the physical properties and mechanical properties of particle boards made from mahogany wood powder waste. In this study, the materials used are mahogany wood powder, citric acid, and PVAC. The composition used in the manufacture of the specimen is 60% wood powder and 40% adhesive and is pressed with a pressure of 15 kg/cm2 for 10 minutes. The particleboard is tested for its physical and mechanical properties and will be compared with SNI 03-2105-2006. The results showed that the average density value ranged from 0.47-0.54 g/cm3 with the highest particleboard density value obtained at 180 °C pressing temperature. The average moisture content value ranges from 6.1-7.2% with the highest particleboard moisture content value obtained at 140 °C pressing temperature. The average MOE value ranges from 2135.7-2401.3 kg/cm2 with the highest particleboard MOE value obtained at 180 °C pressing temperature. The average MOR value ranges from 31-38.3 kg/cm2 with the highest particleboard MOR value obtained at 160 °C pressing temperature. In the physical properties test the entire particleboard has met the standard. However, in the mechanical properties test, the entire particleboard did not meet the standard. The best treatment in this study is the particleboard resulting from the treatment of a pressing temperature of 160 °C.

SIMULASI MANUFAKTUR MOLDING OUTSOLE UNTUK APLIKASI SEPATU SAFETY BERBAHAN DASAR LIMBAH MENGGUNAKAN COMPUTER NUMERICAL CONTROL (CNC)

2025-07-30T21:10:23+07:00

Limbah ban dan plastik di Indonesia menjadi tantangan lingkungan yang membutuhkan solusi inovatif dan berkelanjutan. Artikel ini bertujuan untuk membahas perancangan dan menganalisis cetakan (molding) outsole sepatu safety dengan memanfaatkan limbah tersebut sebagai bahan baku utama. Desain dilakukan menggunakan perangkat lunak CAD Autodesk Inventor, sedangkan simulasi jalur pemesinan dilakukan melalui software CAM Mastercam dan diterapkan pada mesin CNC 3-axis. Tiga metode pemesinan dibandingkan, yaitu pemesinan manual, Computer Aided Manufacturing (CAM) dengan material H13 Tool Steel, dan CAM dengan Aluminium 6061. Hasil kajian ini menunjukkan bahwa metode CAM jauh lebih efisien dibandingkan metode manual, dengan efisiensi waktu tertinggi diperoleh pada penggunaan Aluminium 6061. Material H13 menunjukkan keunggulan dalam hal ketahanan panas dan keausan, cocok untuk produksi massal, sementara Aluminium lebih ekonomis untuk prototipe. Integrasi CAD-CAM dan CNC mampu meningkatkan efisiensi dan kualitas produksi cetakan. Pendekatan desain molding yang terotomatisasi dan ramah lingkungan melalui pemanfaatan limbah lokal, serta penggunaan simulasi CAM dapat diaplikasikan sebagai alat optimasi manufaktur.