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All Journal IAES International Journal of Artificial Intelligence (IJ-AI) Rekayasa Mesin Sinergi World Chemical Engineering Journal Jurnal Teknik Mesin Scientific Journal of Mechanical Engineering Kinematika Teknomekanik International Journal of Community Service Jurnal Abdimas ADPI Sains dan Teknologi International Journal of Innovation in Mechanical Engineering and Advanced Materials Ramatekno Journal of Engineering and Technological Sciences
Dedik Romahadi
Universitas Mercu Buana
Religion Aerospace Engineering Humanities Astronomy Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Chemistry Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Education Electrical & Electronics Engineering Energy Engineering Environmental Science Industrial & Manufacturing Engineering Languange, Linguistic, Communication & Media Law, Crime, Criminology & Criminal Justice Library & Information Science Materials Science & Nanotechnology Mechanical Engineering Public Health Social Sciences Other

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INDUCED DRAFT FAN DOMINANT FREQUENCY DETECTION USING SHORT-TIME FOURIER TRANSFORM METHOD Dedik Romahadi; Wiwit Suprihatiningsih; Gian Villany Golwa; Mahesh Kumar
Jurnal Rekayasa Mesin Vol. 14 No. 2 (2023)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/jrm.v14i2.1305

Abstract

Weak suction and large vibrations indicate an Induced Draft Fan (IDF) problem. The Fast Fourier Transform (FFT) method cannot be applied to non-stationary vibration signals. Therefore, this study aims to analyze non-stationary vibration signals for IDF vibration signals at start-up so that the source of damage to the IDF can be found. The research process begins with a brief measurement of both bearing locations with horizontal and axial axes. Processing of the vibration signal from the measurement using the FFT method and the Short Time Fourier Transform (STFT). Based on the STFT spectrogram graph for measurements on the horizontal and axial axes, the dominant frequency values are the same. The frequency with the largest amplitude value is at one RPM IDF or 25 Hz. High vibration at 1 RPM is a big indication that the IDF is experiencing unbalance.
A review towards Friction Stir Welding technique: working principle and process parameters Rikko Putra Youlia; Diah Utami; Dedik Romahadi; Yang Xiawei
SINERGI Vol 27, No 3 (2023)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2023.3.001

Abstract

Friction Stir Welding (FSW) is a solid-state bonding process that employes tools that are not used up and can function to connect two opposite workpieces without melting the workpiece material. The friction force has been micro-structurally tested to reformat or transform the inner state of the structure properties (atomic formation) form in metal since the kinetic energy of friction has been utilised in one of the welding techniques. Right afterwards, the studies reported that the mechanical properties also underwent a significant deformation. The aim is to determine the effect of Welding Procedure Specification (WPS) product quality. As it develops through research and applied experiments, the branch of friction-based welding discipline can be classified depending on how the friction mechanism can produce the finest solid-state joint, which is suitable to the typical property of metal and can be maximised by joint configuration. Friction Stir Welding is a friction-based welding technique that uses the stirring tool to generate friction while the workpieces are stuck on the line of the FSW joint configuration. The relevant correlations amongst process parameters and inside its respective adjustable variables are constructed to the finest principles that produced top-grades empirical reports of the weld properties. In this review, the explanation of the working principle and clarification of process parameters are presented. The cited references are selected from creditable and verifiable articles and books in the last ten years. Expectedly, it will be able to pioneer a new face of simple and understandable review articles.
Resonance analysis of fan blade design using Finite Element Method Dedik Romahadi; Rikko Putra Youlia; Himawan S. Wibisono; Muhammad Imran
SINERGI Vol 28, No 1 (2024)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2024.1.014

Abstract

Fan motors move liquids, such as air, in the gas phase from one place to another. The frequency of the fan blades, which are the main components of the fan motor, can vary. It is crucial to know the frequencies of each fan blade to avoid design failures caused by resonance. This research analyzes the effect of differences in the angle and number of blades on the natural frequency of the fan to avoid resonance with the motor rotation frequency. Modeling and simulation using the finite element method in the Solidworks application are used to determine the natural frequencies of the fan. Fans come in various configurations, with blades ranging from two to four, and blade pitch can be 25°, 30°, or 40°. Variations in the number of fan blades and changes in blade pitch show that the low mode shape does not affect the natural frequency, while the high mode has a negligible effect. The natural frequency of fan blades 2, 3, and 4 exhibits variations when operated with motors running at 25, 35, or 50 Hz. The findings imply that the fan blades' inherent frequency does not align closely with the motor rotational frequency, indicating that the design is safe.
Studi Variasi Getaran Poros Rotor Dengan Satu Disc Pada Journal Bearing Menggunakan Metode FFT Dan Simulasi FEA Rachmanu, Fatkur; Turmudi, Agung; Karmiadji, Djoko Wahyu; Jalaluddin, Mai Nursherida; Romahadi, Dedik
JURNAL RAMATEKNO Vol 4 No 1 (2024): Ramatekno_Vol_4_No_1
Publisher : LPPM Politeknik Enjinering Indorama

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.61713/jrt.v4i1.164

Abstract

Mesin berputar sangat penting dalam banyak aplikasi di sektor industri. Salah satu komponen yang paling penting dalam mesin berputar adalah penggunaan journal bearing. Metode Fast Fourier Transform (FFT) digunakan untuk analisis getaran dalam menguji sistem getaran poros rotor dengan satu disc pada komponen journal bearing. Pengujian ini menggunakan oli SAE 30 dan variasi putaran motor beroperasi pada rentang 1500 rpm hingga 2500 rpm, dengan kenaikan 200 rpm tiap pengamatan. Pengukuran getaran dilakukan pada posisi sensor secara vertikal di journal bearing. Hasil pengukuran berupa spektrum FFT menggunakan VibXpert menunjukkan adanya gejala misalignment, dengan munculnya nilai amplitudo tertinggi pada putaran 1x, 2x, dan 3x rpm pada setiap kenaikan putaran. Putaran kritis pada poros dihitung dengan menggunakan software Ansys, dengan hasil mencapai 6568,8 rpm di atas putaran operasi, sehingga aman untuk digunakan pada putaran operasi.
Applying Bayesian networks in making intelligent applications for static and dynamic unbalance diagnosis Romahadi, Dedik; Fitri, Muhamad; Feriyanto, Dafit; Hidayat, Imam; Imran, Muhammad
IAES International Journal of Artificial Intelligence (IJ-AI) Vol 13, No 1: March 2024
Publisher : Institute of Advanced Engineering and Science

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.11591/ijai.v13.i1.pp174-184

Abstract

One of the problems often encountered in vibration analysis is unbalanced or imbalanced, namely the occurrence of a shift in the center of mass from the center of rotation to cause high vibrations. Unbalance itself is divided into two, namely static and dynamic unbalance. Identification of the right type of unbalance must be done because each type of unbalance requires different handling. Therefore, this study aims to design a system to identify the type of unbalance based on the required parameters. The system design determines the input and then builds an algorithm by combining vibration analysis methods and Bayesian networks (BN). Systems and applications are built using MATLAB. After the application is finished, testing is carried out using vibration measurement data obtained from a demo machine that has previously been conditioned for damage. The BN method has been successfully applied to the unbalance diagnosis system. When there is evidence of large amplitude in 1X the frequency spectrum and the value of the static phase range, the percentage of static unbalance from 26.8% increases to 75%. The system can predict all testing data quickly and precisely for the six experiments.
Intelligent system design for identification of unbalance and misalignment using Fuzzy Logic methods Romahadi, Dedik; Feriyanto, Dafit; Anggara, Fajar; Wijaya, Fathoni Putra; Dong, Wang
SINERGI Vol 28, No 2 (2024)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/sinergi.2024.2.004

Abstract

Vibration analysis identifies emerging vibration problems before they become unmanageable and cause unforeseen delays. This can be accomplished by monitoring engine vibration continuously or at specific intervals. Unbalance is a common vibration issue caused by the center of mass shifting from the center of rotation, leading to misalignment and excessive vibration between shafts. To prevent this, manual monitoring is required, but it is time-consuming. Therefore, intelligent system monitoring is necessary to save time. Using a large amount of vibration, spectrum, and phase data as input, this project aims to develop a diagnostic application for motor problems based on vibration signals. Fuzzy logic is implemented in MATLAB software to process a considerable amount of input data for all vibrations, spectrums, and phases using the fuzzy logic method. A vibration meter is used to collect vibration data from the demonstration machine. All input data will be processed by the fuzzy system based on predefined fuzzy rules that must provide accurate results for the actual operating conditions of the demonstration machine. Conducting experiments will help the intelligent system correctly detect damage from misalignment and imbalance. The intelligent fuzzy logic system can accurately diagnose damage caused by misalignment and unbalance on the demonstration machine.
Analysis of Characteristics of S45C Steel Changes due to the Quenching and Tempering Process Golwa, Gian Villany; Romahadi, Dedik; Arwati, I Gusti Ayu
World Chemical Engineering Journal VOLUME 6 NO. 2 DECEMBER 2022
Publisher : Chemical Engineering Department, Engineering Faculty, Universitas Sultan Ageng Tirtayasa

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.36055/wcej.v6i2.17611

Abstract

S45C steel has a carbon content of 0.50% and its classified as medium carbon steel. The main element content of S45C is carbon (C) is 0.50%, sulphur (S) is 0.035%, and manganese (Mn) is 0.80%. Tempering is a heat treatment process in which the hardening or normalizing process was previously carried out on steel. The research method was carried out where the steel was heated below the critical temperature and cooled. Quenching is a process of rapidly cooling the material from austenitizing from a temperature range of 815 °C to 870 °C for steel. S45C steel was quenched at 950 °C for 120 minutes, then tempered at 700 °C, and 500 °C for 120 minutes. The raw material sample (without heat treatment) is the initial reference standard among the samples undergoing the heat treatment process. They are then analyzed, and the influence and changes in the characteristics after that. In addition, changes in mechanical properties due to the heat treatment process experienced by S45C steel use tensile tests, Charpy impact tests, hardness tests and microstructures. The research results on the quenching process sample were tempered at a temperature of 500 °C and held for 120 minutes, increasing tensile strength by 17.1% and yield strength of 56.82%.
ANALISIS SINYAL GETARAN POMPA COOLING WATER TIPE SENTRIFUGAL MENGGUNAKAN METODE FFT DAN ISO 10816-3 Adinarto, Tri Wahyu; Romahadi, Dedik
Jurnal Teknik Mesin (Journal Of Mechanical Engineering) Vol 13, No 1 (2024)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/jtm.v13i1.20992

Abstract

Abstrak-- Penelitian ini dilatarbelakangi oleh getaran pompa cooling water  P9114B yang berlebih Hal ini menyebabkan performa pompa menurun untuk menghindari terjadinya breakdown maintenance maka perlu dilakukan analisis vibrasi. Penelitian ini bertujuan untuk mengetahui titik lokasi kerusakan pada pompa sentrifugal cooling water P9114B di PT SAU dengan menggunakan sinyal getaran analisis dan dengan mengukur besarnya getaran dan menyajikannya ke domain frekuensi (spectrum). Metode yang digunakan untuk analisis penelitian ini adalah metode Fast Fourier Transform (FFT). Pengukuran dilakukan pada 3 titik pengukuran (horizontal, vertikal dan aksial) kondisi pompa yang diteliti termasuk dalam kategori kelompok 2 yaitu mesin berukuran medium mengacu pada standar ISO 10816-3. Diperoleh hasil dengan kriteria warna merah (Danger) yang dapat diartikan bahwa pompa dalam kondisi dapat menyebabkan kerusakan yang lebih parah jika terus beroperasi. Dari hasil analisis sinyal getaran yaitu dengan dominan frekuensi pada 24,17 Hz (1X RPM) dan nilai amplitudo RMS velocity pada Inboard Pump horizontal sebesar 6,67 mm/. Frekuensi dominan tertinggi kedua 145 Hz (Blade Pass Frequency) yaitu sebesar 3,8 mm/s dan 2X RPM yang lebih rendah dari 1X atau 6X.  Perbedaan phase arah radial Inboard pump dengan radial inboard motor sebesar 1800. Dari analisis data pengukuran getaran spektrum domain frekuensi dan pengukuran phasa maka disimpulkan pompa mengalami kerusakan misalignment parallel dan cavitasi.. Setelah dilakukan perbaikan dengan penggantian impeller pompa didapatkan penurunan vibrasi dari 6,67 mm/s turun menjadi 2,5 mm/s. Berdasarkan ISO 10816-3 klasifikasi pompa dalam fondasi rigid ,daya 114Kw dan size medium , disimpulkan pompa dalam kondisi Satisfatory. Kata Kunci: Pompa, ketidakseimbangan, misalignment, ISO-10816-3, pompa cooling water, Fast Fourier Transform,
Design of Temperature Control System on UV Weathering Chamber Based on PID Zakaria, Zakaria; Romahadi, Dedik; Fitri, Muhamad
Jurnal Teknik Mesin (Journal Of Mechanical Engineering) Vol 12, No 1 (2023)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/jtm.v12i1.16505

Abstract

The influence of high temperature and exposure to ultraviolet (UV) radiation from sunlight, rain, and humidity causes damage to the composite material and consequently, reduces its mechanical performance. Weathering experiments can be carried out outdoors or under laboratory conditions. Material degradation tests can be carried out directly using natural conditions or laboratory test equipment that artificially simulates natural conditions. An automatic temperature control system is needed to keep the setpoint stable during the degradation test. The controller on the system uses Arduino based on Proportional, Interval, and Derivative (PID). The test was carried out by running the system with different PID parameter values three times to obtain the most optimize-tingling results in maintaining the setpoint at steady state conditions. Based on the results of tests that have been carried out with a setpoint of 40⁰C, the most optimal results are obtained with values of Kp=10, Ki=20, and Kd=30. The average temperature is 40.02⁰C with an average error percentage of 2% and an average accuracy rate of 98%.
Analisis Getaran Displacement Drum Roller Menggunakan FFT dan STFT Ilhamullah, Ilhamullah; Romahadi, Dedik; Youlia, Rikko Putra
Jurnal Teknik Mesin (Journal Of Mechanical Engineering) Vol 12, No 1 (2023)
Publisher : Universitas Mercu Buana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.22441/jtm.v12i1.16681

Abstract

Drum Roller adalah mesin yang dirancang untuk pengujian ketahanan ban mobil setelah proses produksi. Peralatan  berputar, dan realisasi diagnosis waktu nyata dari kesalahan getaran frekuensi umum sangat penting untuk memantau kondisi Drum Roller. Getaran yang tinggi dapat merusak bagian-bagian penting mesin dan mempengaruhi kualitas ban. Maka dengan itu, dilakukannya analisis getaran untuk mengidentifikasi kerusakan dengan Metode Fast Fourier Transform (FFT)  dan Metode Short Time Fourier Transform (STFT). Pemrosesan sinyal dilakukan dari input hasil pengukuran getaran berupa data domain waktu pada MATLAB kemudian metode FFT dan STFT diterapkan menggunakan fungsi filter jendela Hanning. Selanjutnya memvalidasi hasil analisis kerusakan. Berdasarkan hasil pengukuran getaran didapatkan sumber getaran terbesar pada posisi radial yaitu getaran yang dihasilkan sebesar 96 μm RMS. Dari grafik spektrum dan spektogram Fourier transform radial dan axial keduanya dapat disimpulkan bahwa adanya indikasi unbalance pada impeller dengan frekuensi 6.7 Hz yang menunjukkan satu kalinya frekuensi Drum Roller. Berdasarkan standar analisis getaran Displacement (ISO 10816-3), getaran Drum Roller masuk pada Zona C, bermakna mesin hanya diizinkan beroperasi dalam waktu singkat. Hasil analisis bahwa Drum Roller mengalami unbalance terbukti benar dengan turunnya nilai getaran menjadi 18 μm RMS.
Co-Authors A. M. Leman Abda Abda Abdul Hamid Abdul Hamid Abdulmalik, Samir Sani Abdulmalik, SS. Adinarto, Tri Wahyu Aditya, Bima Agung Wahyudi Biantoro Alfian Noviyanto Alief Avicenna Luthfie Alina, Alina Andi Firdaus Sudarma Anggara, Fajar Arvisyah, Diar Auf, Abdurrahman Chaeroni, Amat Dafit Feriyanto Desti Dorion, L. B. Diah Utami Diah Utami, Diah Enggar Pur nama , Rama Fajar Anggara Feleke, Aberham Genetu Genetu Feleke, Aberham Ghufron, Hanif Gian Villany Golwa Hadi Pranoto Hadi Pranoto Hadi Pranoto Hanif Ghufron Hifdzul Luthfan Habibullah Himawan S. Wibisono Hui Xiong Hui Xiong Hui Xiong I Gusti Ayu Arwati Ilhamullah, Ilhamullah Imam Hidayat Jalaluddin, Mai Nursherida Karmiadji, Djoko Wahyu Kurniawan, Rizki Nur Afami L. B. Desti Dorion Mahendra, Tito Syahril Sobarudin Izha Mahesh Kumar Maris, Iman Maulana Yusuf Md Radwanul Karim Muhamad Fitri Muhammad Imran Muhammad Imran Muhammad Sulthan Yafiq Murtyas, Solli Dwi Nanang Ruhyat Noviana, Agus Nugroho, Irfan Evi Nurato Pramana, Putratama Aziz R. Dwi Pudji Susilo Rachmanu, Fatkur Rahmatullah, Rizky Rikko Putra Youlia Rizki Nur Afami Kurniawan Saputra, Gofar Julio Sisliana, Azara Vigha Solli Dwi Murtyas Sri Anah Subekti Supaat Zakaria Susilo, R. Dwi Pudji Turmudi, Agung Wang Dong Wermasaubun, Hendrikus Wibowo, Agus Setiawan Wijaya, Fathoni Putra Wiwit Suprihatiningsih Xiong, Hui Yafiq, Muhammad Sulthan Yang Xiawei Yishuang, Tang Yosua Heru Irawan Yudha Aji Pramono Zakaria Zakaria Zakaria, Supaat