Article Per Year (5 Year)
p-Index From 2020 - 2025
1.578
P-Index
This Author published in this journals
All Journal JOURNAL OF MECHANICAL ENGINEERING, MANUFACTURES, MATERIALS AND ENERGY Jurnal Rekayasa Material, Manufaktur & Energi Jurnal Abdi Insani IRA Jurnal Teknik Mesin dan Aplikasinya (IRAJTMA) IRA Jurnal Pengabdian Kepada Masyarakat Jurnal Ilmiah Teknik Mesin & Industri (JITMI)
Bobby Umroh
Universitas Tjut Nyak Dhien Medan, Jl. Gatot Subroto/Jl. Rasmi No 28, Medan 20123
Aerospace Engineering Agriculture, Biological Sciences & Forestry Automotive Engineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Economics, Econometrics & Finance Education Electrical & Electronics Engineering Energy Engineering Environmental Science Health Professions Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Law, Crime, Criminology & Criminal Justice Materials Science & Nanotechnology Mathematics Mechanical Engineering Other

Published : 15 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 15 Documents
Search

 1   2 
SIMULASI KEKUATAN MEKANIS MATERIAL KOMPOSIT TEMPURUNG KELAPA MENGGUNAKAN METODE ELEMEN HINGGA Darianto, Darianto; Siregar, Amru; Umroh, Bobby; Kurniadi, Dedi
JMEMME (JOURNAL OF MECHANICAL ENGINEERING, MANUFACTURES, MATERIALS AND ENERGY) Vol 3, No 1 (2019): EDISI JUNI
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (201.513 KB) | DOI: 10.31289/jmemme.v3i1.2443

Abstract

Komposit merupakan sejumlah sistem multi fasa sifat gabungan, yaitu gabungan antara bahan matriks atau pengikat dengan penguat. Penelitian ini dilakukan menggunakan metode kuantitatif dengan rancangan penelitian eksperimental serta membandingkan hasil pengujian pada metode elemen hingga yang dilakukan penelitian di laboratorium. Objek penelitian berupa serat tempurung kelapa yang dipilih karena melimpahnya sumber daya alam tersebut. Spesimen matriks resin dibuat dengan standar ASTM D 638 M-84 dengan bahan resin epoksi dan katalis menggunakan metode pengecoran. Teknik pengumpulan data yang digunakan adalah teknik pengujian laboratorium. Instrumen yang digunakan berupa lembar pencatatan. Dari hasil penelitian yang dilakukan didapatkan kekuatan tarik komposit tertinggi dengan tata letak random sebesar 3,38 kgf/mm2 dan perpanjangan sebesar 0,38 mm, Cross sebesar 3,03 kgf/mm2 dan perpanjangan sebesar 0,86 mm, continuous sebesar 2,24 kgf/mm2 dan perpanjangan sebesar 1,03 mm, woven sebesar 1,64 kgf/mm2 dan perpanjangan sebesar 0,64 mm. Bentuk patahan menunjukan bahwa hasil pengujian tarik mengalami patahan getas, karena ujung patahan terdapat patahan 900 dan kasar di karenakan adanya mekanisme fiber pull out.
INVESTIGATION OF MECHANICAL BEHAVIOR OF POLYMERIC FOAM MATERIALS REINFORCED BY OIL PALM EMPTY FRUIT BUNCHES (OPEFB) FIBERS DUE TO STATIC AND DYNAMIC LOADS Zulfikar, Achmad Jusuf; Umroh, Bobby; Siahaan, Muhammad Yusuf Rahmansyah
JMEMME (JOURNAL OF MECHANICAL ENGINEERING, MANUFACTURES, MATERIALS AND ENERGY) Vol 3, No 1 (2019): EDISI JUNI
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (534.099 KB) | DOI: 10.31289/jmemme.v3i1.2416

Abstract

Polymeric composite foam with EFB fiber reinforced is new material that can be utilized as an alternative engineering material. EFB fiber utilization becomes the center of subject in this research. Moreover, these composites are unique with the presence of cavities (foam) in the matrix of unsaturated polyester resin. It results a decrease in density of the material that formed, and obtain a thermoset polymer composite material lighter than any else similar type. The objective of this study is to obtain the best manufacturing techniques of composite material, the mechanical behavior of these materials due to tensile static loading and high strain rate impact, and the distribution of foam that occur in the material that formed as a result of blowing agent (BA) from the type of polyurethane (PU). In this research, the sample formed into standard specimen of testing, such as ASTM D638 for static tensile test, and impact test specimen. Mechanical’s behaviors that are obtained in this research are density, tensile strength, modulus of elasticity (E), the incident stress, and dynamic modulus of elasticity of the material. For static testing was performed according to standard ASTM D638 tensile and impact test using the Kolsky’s method. To know the distribution of foam that occur in the material, were observed using Scanning Electron Microscope instrument (SEM). To determine the stress distribution in this material, then conducted a computer simulation using Ansys. The best result obtained by the composition of this material based on material composition, which resin consumption can be reduced by the presence of BA as well as mechanical strength, good enough for molding. The best composition in this study will be used in subsequent studies, namely the design and manufacture of traffic cones from this material.
ANALISIS KEKUATAN STRUKTUR RANGKA MESIN PENGERING BAWANG MENGGUNAKAN PERANGKAT LUNAK ANSYS APDL 15.0 Sofyan, Azwir; Glusevic, Jean; Zulfikar, Achmad Jusuf; Umroh, Bobby
JMEMME (JOURNAL OF MECHANICAL ENGINEERING, MANUFACTURES, MATERIALS AND ENERGY) Vol 3, No 1 (2019): EDISI JUNI
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (323.33 KB) | DOI: 10.31289/jmemme.v3i1.2417

Abstract

Typical technology for processing red onion affects the quality of red onion produced. The process of drying red onion is one of the important factors in producing the best quality of red onion. Environmentally friendly and easy operation and maintenance technology is the desired technology. In the process of engine design, the strength of the material and structure are the main factors of the building of the machine. Calculation with finite element method (FEM) is the best choice to obtain information on stress distribution on a machine structure. In this study, the calculation of the FEM method was assisted by Ansys APDL 15.0 software. The objectives of this study were: (1) calculation of the load on the tray structure, (2) the distribution of stress on the tray structure, seat, and frame for red onion dryers, and (3) analyzing the strength of the material using the Tresca and Energy Distortion methods. The input load comes from the weight of the tray and red onion. The analytical method used is the finite element method with the type of structural analysis and Beam 3Node 189 element type. Based on the FEM simulation results, the maximum stress that occurs in the tray is 1.22 MPa and the maximum deflection is 0.0055 mm. The maximum stress in the tray support structure is 33.25 MPa and the maximum deflection is 0.014 mm. The maximum stress on the frame structure of the onion drying machine is 0.89 MPa and the maximum deflection is 0.000235 mm which occurs in the middle of the machine structure. Using the Tresca and Distortion Energy theories, it is found that the stresses that occur are still far from the failure criteria for all structures. Likewise, the deflection that occurs is very small so that the construction of the onion drying machine is safe to use.
ANALISA KINERJA MATA PISAU MESIN PENGIRIS KULIT KELAPA MUDA Umroh, Bobby; Darianto, Darianto; Sipangkar, Rinto Supardi
JMEMME (JOURNAL OF MECHANICAL ENGINEERING, MANUFACTURES, MATERIALS AND ENERGY) Vol 3, No 1 (2019): EDISI JUNI
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (1023.438 KB) | DOI: 10.31289/jmemme.v3i1.2429

Abstract

Kelapa muda umumnya disajikan secara alami dengan bentuk kerucut di atas. Proses pembentukan kelapa ini sudah dilakukan secara manual di industri rumah tangga dengan menggunakan sebilah parang. Proses ini memiliki resiko kecelakaan kerja yang tinggi. Kelapa yang dihasilkan pada proses ini memiliki bentuk yang kurang menarik, tidak seragam, dan sulit untuk dibuka. Oleh sebab itu, dibutuhkan alat pengiris kulit kelapa muda yang dapat menghasilkan bentuk yang lebih baik, seragam, dan aman untuk digunakan. Untuk merancang alat pengiris kulit kelapa muda, penting untuk melakukan analisis mekanisme pemotongan kulit kelapa muda. Tujuan dari penelitian ini adalah untuk menganalisis mekanisme pemotongan kulit kelapa muda, membangun model matematika pendugaan gaya spesifik pemotongan, dan mendapatkan daya pemotongan maksimum pemotongan kulit kelapa muda. Variasi faktor sudut ketajaman, sudut potong, dan sisi mata pisau dioptimalkan untuk menghasilkan gaya potong terendah. Model matematika telah dibangun untuk menduga gaya pemotongan maksimum untuk pisau satu sisi menajam dan dua sisi menajam dengan sudut potong (θ) 00, 150, dan 300. Dari hasil penelitian disimpulkan bahwa jenis pisau yang menghasilkan gaya pemotongan terendah adalah pisau dua sisi menajam dengan sudut ketajaman 100 dan sudut potong 300. Daya terendah untuk pemotongan tegak lurus kulit kelapa muda adalah 0,12 kW yang dihasilkan dengan menggunakan pisau dua sisi menajam dengan sudut ketajaman 100 dan sudut potong 300. Daya pemutaran maksimum yang dibutuhkan untuk memotong kulit kelapa muda adalah 0,75 kW.
ANALISA GAYA DAN SUDUT RAHANG PADA ALAT PEMBUKA BUAH DURIAN METODE GERAK PUTAR RELATIF Nainggolan, Danis; zulfikar, Achmad Jusuf; umroh, bobby
JMEMME (JOURNAL OF MECHANICAL ENGINEERING MANUFACTURES MATERIALS AND ENERGY) Vol 3, No 2 (2019): EDISI DESEMBER
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (208.582 KB) | DOI: 10.31289/jmemme.v3i2.2813

Abstract

Pada prinsipnya, teknologi dipergunakan manusia untuk memberikan kemudahan dan peningkatan terhadap efisiensi kerja, baik ditinjau dari sisi waktu maupun biaya produksi. Pada penelitian ini, sebuah alat pembuka buah durian dengan metode rahang berputar telah dibangun dan telah diuji. Analisa gaya untuk membuka buah durian dengan menggunakan alat ini menjadi fokus utama dalam penelitian ini. Tujuan penelitian ini ialah mengukur beban dan sudut pengupasan buah durian serta menghitung kapasitas dan efisiensi alat tersebut. Metode pengambilan data pengujian ialah dengan meletakkan alat pengukur beban pada alat pembuka buah durian dan mencatat nilai beban yang diberikan selama proses pengujian berlangsung. Buah durian diletakkan dalam rahang khusus yang dapat digerakkan berputar relatif terhadap pisau. Jenis buah durian yang dipergunakan dalam penelitian ini terdiri dari buah durian matang dan buah durian mentah. Hasil yang diperoleh ialah gaya rata-rata yang dibutuhkan untuk membuka buah durian matang ialah 99 N dengan sudut rahang rata-rata 45o dan waktu rata-rata 9,5 detik. Sedangkan untuk buah durian mentah, gaya rata-ratanya ialah 134 N dengan sudut rahang rata-rata hingga 80o dan waktu proses pembukaan rata-rata hingga 15 detik. Kapasitas alat untuk buah matang ialah 185 buah/jam dan buah mentah 144 buah/jam. Efisiensi alat untuk buah matang dan mentah adalah sama, yaitu mencapai hingga 85%.
DESIGN AND MANUFACTURE OF SKATEBOARD FROM BANANA STEM Zulfikar, Achmad Jusuf; Umroh, Bobby; Siahaan, Muhammad Yusuf Rahmansyah
JMEMME (JOURNAL OF MECHANICAL ENGINEERING MANUFACTURES MATERIALS AND ENERGY) Vol 3, No 2 (2019): EDISI DESEMBER
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (241.858 KB) | DOI: 10.31289/jmemme.v3i2.3022

Abstract

A skateboard is a small piece of wood shaped like a surfboard with four wheels attached to it that is used to glide on a certain track. In general, this tool is made using wood material taken from nature and vulnerable to environmental damage issues. In this research, the waste of banana stems will be processed into the main raw material for skateboarding. The type of material chosen is the type of composite material with banana stem waste selected as reinforcement and polyester resin as the matrix material. The purpose of this research is to design and manufacture a skateboard made of composite fiber reinforced banana stem fibers and to test its flexural strength to obtain the characteristics of the material formed. The design was carried out with the help of the 2007 version of Autocad software by following commercial skateboard standards.  Flexural testing was carried out at the Impact and Fracture Research Center laboratory, Faculty of Engineering, University of North Sumatra. Static static testing of polymer composite board specimens from banana stems obtained the average value data for the composition of 5% banana stems is 9.81 MPa, for the composition of 10% banana stems an average of 13.60 MPa, and composition of 15% banana stems the average is 27.20 MPa. 2. The analysis shows that the best composition is 15% of banana stems, with an average flexural strength value of 27.20 MPa. Therefore, the composition used in this study is the composition of 15% reinforcement of banana stems.
Analisis Tegangan Mekanik Pada Mesin Press Hidrolik Dengan Beban 20 Ton Sarjana, SS; Prawoto, Yogi; Umroh, Bobby; ., Rahmatullah; Idris, Muhammad
Rekayasa Material, Manufaktur dan Energi Vol 6, No 2: September 2023
Publisher : Fakultas Teknik UMSU

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30596/rmme.v6i2.16551

Abstract

Hydraulic press machine is a tool used for work that requires a compressive action force. The stress distribution that occurs in this study will be determined in the development of a press machine under a state of pressing with a load of 20 tons. Researchers use Finite Element Analysis (FEA) to generate data on the stress circulation in the engine construction. The research objectives: (1) Calculate the hydraulic pressure strength in theory, (2) Calculate the mechanical stress in the hydraulic press construction manually using the ANSYS R15.0 software, (3) Calculate the strength of the hydraulic press construction manually and using the ANSYS R15 software. .0. In this review, FEA estimation is completed with the help of Ansys Workbench R15.0 programming. The information load comes from hydraulic pressure. The inspection strategy utilizes FEA with the type of underlying structural analysis. FEA simulation results stated, the maximum stress that occurs in the table is 98.646 MPa and the maximum deformation is 0.21613 mm. The results of Ansys analysis stated that the maximum stress that occurs on the table is 98.646 MPa and the maximum deformation is 0.21613 mm. Considering the Tresca hypothesis, it is found that the stresses and deformations that occur are below the standard for structural failure. So that the frame of the hydraulic press is safe for use in a load of 20 tons.
Implementasi Keselamatan dan Kesehatan Kerja (K3) Pada Aktivitas Fabrikasi (Pengelasan, Pemotongan, Penggerindaan) di Kota Medan ., Rahmatullah; Umroh, Bobby; Amiruddin, Arfis; Siregar, Ahmad Marabdi
Rekayasa Material, Manufaktur dan Energi Vol 5, No 2: September 2022
Publisher : Fakultas Teknik UMSU

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30596/rmme.v5i2.11447

Abstract

Occupational safety and health (OSH) is basically in the interest of all parties and is a basic right for workers. A safe and comfortable working process is an asset that is maintained continuously for quality and timely production. Work accidents are something that is highly avoided, work accident control must be carried out with methods that are in accordance with the field and industrial conditions. The purpose of the discussion in this paper is, how to control OSH in the fabrication industry in a sustainable manner, how to create good OSH regulations and make the production process safe and comfortable, how to form a good and professional work attitude. Work accidents that occur are actually the end result of a rule and unsafe working conditions. 85% of the causes of accidents are human factors. The fabrication industry carries out several processes such as welding, cutting, final processing and other supporting processes in the workshop. Recommendations have been made and implemented to reduce and control work accidents. The application of OSH in accordance with the concept of occupational health and safety management, theoretically the industry will be able to reduce the number of work accidents even to zero accidents from work accidents.
Analisis Kualitas Produk Botol 30ml Dengan Parameter Temperatur Pada Mesin Injection Molding Model Blow Elapri, Bima Yoel; Ramdan, Dadan; Umroh, Bobby
Jurnal Ilmiah Teknik Mesin & Industri (JITMI) Vol 2, No 2 (2023): Jurnal Ilmiah Teknik Mesin & Industri (JITMI), November
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31289/jitmi.v2i2.3424

Abstract

Injection molding is one method that is widely used because of the lower cost required. The resulting plastic product is inseparable from the problem of product defects. This research uses quantitative methods and data collection or field on the subject of research, after that analyzing each parameter. The results of this study the occurrence of several defects in the product, namely short molding product defects have the most defects, namely 3, while over mold, sink mark and weldmark or flow product defects are 2 and the least is the hole product defect, namely 1. The setting at temperature determines the quality, especially in terms of appearance, at a temperature of 190 0C gives a much better product quality compared to temperatures of 180 and 200 0C. Analyze the optimal screw speed of 8 Rpm so that the resulting product can become a desired bottle product. Analysis of product defects that occur are Sink Mark, Weldmark or flow mark, Shrinkage and Over Mold which occurs at temperatures of 180 - 200 0C. The defects that most often arise because the mold has uneven lines so that defects occur in bottle products.
Pembuatan Mesin Internal Mikser Bijih Plastik Kapasitas 50 g/h Purba, Jepriadi; Iswandi, Iswandi; Umroh, Bobby
Jurnal Ilmiah Teknik Mesin & Industri (JITMI) Vol 2, No 1 (2023): Jurnal Ilmiah Teknik Mesin & Industri (JITMI), May
Publisher : Universitas Medan Area

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31289/jitmi.v2i1.1952

Abstract

This research aims to test and validate the performance of the IMBP Machine that has been created, ensuring that the machine can operate effectively and perform its components' functions as expected. Additionally, the objectives of this study include achieving the desired processing results of 50 grams per hour of plastic seeds and systematically developing the process of manufacturing the IMBP Machine, starting from the construction of the iron frame, gear housing, end plate, barrel, hopper, cover, packing, knife shaft, blades, binding shaft, and finishing process. The research methodology employed encompasses field observation, literature review, testing and measurement methods, as well as analytical methods. Field observation is utilized to observe and gather data from machines operating in the field. Literature review is conducted to obtain information related to the theory and practices of the IMBP Machine. Testing and measurement methods are employed to evaluate machine performance and collect data regarding the achieved processing outcomes. Furthermore, the analytical method is used to compare the obtained data with the desired specifications, thus validating whether the machine has achieved the intended targets. The research findings demonstrate that this machine successfully produces the IMBP Machine according to the desired specifications. It is proven to function effectively in processing plastic and carbon materials. With the results of this research, it is expected that this machine can contribute positively to plastic waste processing and carbon waste reduction processes.
Co-Authors Ahmad Marabdi Siregar Aldori, Yopan Rahmad Alfifto, Alfifto Amiruddin, Arfis Amru Siregar Dadan Ramdan Darianto, Darianto dedi kurniadi Elapri, Bima Yoel Fauji S, Ahmad Glusevic, Jean Harahap, Uun Novalia INDRA HERMAWAN Iswandi Iswandi Jufrizal Jufrizal Maulana, M Rizky Muhammad Idris Nainggolan, Danis Prawoto, Yogi Purba, Jepriadi Rahmatullah . Salqaura, Siti Alhamra Sarjana, SS Siagian, Martua Sangap Siahaan, Muhammad Yusuf Rahmansyah Siahaan, Muhammad Yusuf Rahmansyah Sianturi, Danial Jack Marbis Sipangkar, Rinto Supardi Sofyan, Azwir Tumangger, Theo Fredrik zulfikar, Achmad Jusuf Zulfikar, Achmad Jusuf Zulfikar, Achmad Jusuf