Article Per Year (5 Year)
p-Index From 2020 - 2025
1.723
P-Index
This Author published in this journals
All Journal Jurnal Mekanik Terapan Jurnal Mesin Nusantara Teknologika JURNAL POLI-TEKNOLOGI Jurnal Polimesin Recent in Engineering Science and Technology
Dewin Purnama
Politeknik Negeri Jakarta
Aerospace Engineering Automotive Engineering Chemical Engineering, Chemistry & Bioengineering Civil Engineering, Building, Construction & Architecture Computer Science & IT Control & Systems Engineering Decision Sciences, Operations Research & Management Electrical & Electronics Engineering Energy Engineering Industrial & Manufacturing Engineering Materials Science & Nanotechnology Mechanical Engineering Transportation Other

Published : 10 Documents Claim Missing Document
Claim Missing Document
Check
Articles

Found 10 Documents
Search

 1 
Analisis Perbandingan Laju Perpindahan Panas Antara Stainless Steel dan CuNi pada Air Cooler Generator PLTA Dewin Purnama; Ryan Nugraha; Vika Rizkia
Jurnal Teknologika Vol 12 No 2 (2022): Jurnal Teknologika
Publisher : Sekolah Tinggi Teknologi Wastukancana

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.51132/teknologika.v12iNo 2.229

Abstract

Pada Pembangkit Listrik Tenaga Air (PLTA) generator berfungsi untuk mengubah energi mekanik yang berasal dari turbin menjadi energi listrik. Berbeda halnya dengan turbin, generator memerlukan pendinginan yang baik untuk memperpanjang umur pemakaian. Untuk menjaga agar suhu dalam generator tetap stabil sesuai dengan suhu yang diharapkan maka digunakan sebuah alat penukar kalor. Alat penukar kalor yang terdapat di generator pada Pembangkit Listrik Tenaga Air (PLTA) adalah tipe compact heat exchanger yang biasa disebut air cooler generator dimana air sebagai media pendingin dan udara di dalam rumah generator sebagai media yang didinginkan. Terdapat 2 bahan dasar tube air cooler generator yaitu stainless steel grade 316L dan CuNi. Penelitian ini bertujuan untuk membandingkan efektivitas dari alat penukar kalor tipe compact heat exchanger material tube stainless steel grade 316L dan CuNi. Metode observasi dan wawancara digunakan dalam penelitian ini, kemudian dilakukan pengolahan data dan analisa dengan menggunakan effectiveness-NTU method dan perhitungan manual yang bersesuaian bagi alat penukar kalor tipe compact heat exchanger. Data-data operasi dan data spesifikasi alat penukar kalor diambil dari suatu perusahaan pembangkit tenaga listrik yang dijadikan objek penelitian. Hasil yang di dapatkan pada penelitian ini adalah bahwa efektivitas air cooler generator material tube stainless steel grade 316L lebih baik jika dibandingkan dengan material CuNi. Hal ini dikarenakan air cooler generator material stainless steel memiliki luas permukaan perpindahan panas yang lebih besar dengan luas sebesar 9,932 m2 dan memiliki efektivitas sebesar 55,34% apabila dibandingkan dengan air cooler generartor material CuNi yang memiliki luas permukaan perpindahan panas sebesar 8,0159 m2 dengan efektivitas rata-rata sebesar 53,78%.
Modifikasi Sistem Penggerak Belt Conveyor T92-BC1 Nur Citra Wahyudianti; Dewin Purnama; Rochsigit Nugroho
Jurnal Mekanik Terapan Vol 4 No 1 (2023): April 2023
Publisher : Politeknik Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32722/jmt.v4i1.5791

Abstract

Belt conveyor is one of the transportation media used to move material in the form of units or bulk spills from one operating system to another. At PT Solusi Bangun Indonesia, one of the belt conveyor is used to alternately transport two types of materials, namely fly ash & bottom ash (FABA) and silica. It causes inconsistent bin filling when the consumption of silica and FABA materials is high at the same time. In addition, problems with the FABA belt conveyor drive system often occur, such as tripping motors, broken chains, and worn sprockets, causing FABA transport to be disrupted. Therefore, it is necessary to modify the belt conveyor drive system so that FABA transport becomes smoother. The methode begins with collecting data in the field or information from supervisors, field studies, carrying out the design process to evaluating the results. The modifications made were by replacing the gearmotor with a power of 11 kW with a rotational output 24 rpm, changing the transmission system from chain-sprocket to a coupling, and increasing the diameter of the head pulley from 478 mm to 560 mm to increase the belt conveyor transport capacity to 125 tons per hour.
Modifikasi Rancangan Mesin Auto Button Insert Menggunakan Metode Quality Function Deployment Dewin Purnama; Patricia Laetitia; Seto Tjahyono; Muslimin Muslimin
Jurnal Mekanik Terapan Vol 4 No 2 (2023): Agustus 2023
Publisher : Politeknik Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32722/jmt.v4i2.5835

Abstract

The development of industrial machinery is advancing with the progress of technology, especially in improving efficiency and product quality. PT. X is one of the electrical component production companies in Indonesia and is continuously striving for machine efficiency in its production. PT. X is developing one of its production machines, namely the auto button insert machine, as a pick and place machine in the assembly of temperature controllers. Modifying the design of the machine aims to reduce the cycle time for each product. Shortening the cycle time can result in one machine accommodating the needs of two new assembly lines that will be created. The previous machine's cycle time, which was 35 seconds per product, is shortened to 17 seconds using the Quality Function Deployment (QFD) method as the approach for designing the new machine. As a result, the cycle time reduction for this machine is 51%.
Analisis Pengendalian Kualitas Produk Reinforcement Suspension Member Menggunakan Metode Six Sigma Dewin Purnama; Zulfikar Mutaqin
Jurnal Mekanik Terapan Vol 4 No 2 (2023): Agustus 2023
Publisher : Politeknik Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32722/jmt.v4i2.5861

Abstract

Customer satisfaction is the main requirement that must be provided by companies with products that meet the specified specifications, and quality is also a crucial factor in supporting customer satisfaction. The problem identified in this study is the occurrence of defects in reinforcement suspension member products that exceed the company's defect tolerance limit of 0.1%. The aim of this study is to analyze the causes of defects using the Six Sigma method with the DMAIC steps (Define, Measure, Analyze, Improve, and Control), and to propose improvements to address the number of defects that occur. Some of the tools used in this study are the fishbone diagram and the P control chart. The results of this study indicate that the factors causing the failures are the method and environment factors. Meanwhile, the data processing resulted in a DPMO of 2745.21 with a sigma level of 4.28 a process capability index (Cp) of 1.43, and an average defective product rate of 0.28% with a total of 392 defective pieces, while the company's defect tolerance limit is 0.1%. Therefore, the company needs to implement quality control by making improvements to the method and environment factors.
Effect of heat input on the microstructure and hardness of AISI 321 stainless steel welds using ER 347 filler metal Herry Oktadinata; Dewin Purnama; Debby Laksana Anugrah
Jurnal Polimesin Vol 22, No 2 (2024): April
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v22i2.4945

Abstract

Stainless steel is widely used in various fields, one of which is AISI 321, which is used for high-temperature applications because of its high resistance to creep and intergranular corrosion. The type of filler metal and heat input on stainless steel welds play an essential role in determining the microstructure and mechanical properties of the welded joints. The purpose of this experiment was to evaluate the microstructure and mechanical properties of AISI 321 stainless steel welds with variations in heat input. This study is expected to explore the performance of this weld joint, which can be anticipated in relevant fields. The welding method used in this experiment was Gas Tungsten Arc Welding (GTAW) with ER 347 as filler metal. Welding was carried out on three samples with a heat input of 0.92 kJ/mm, 0.64 kJ/mm, and 0.52 kJ/mm, respectively. The tests included tensile strength, Vickers microhardness, and microstructure observations. The tensile test results showed that a fracture occurred in the Base Metal (BM) area, indicating that the strength of the weld joint was higher than that in the BM. The Vickers microhardness test results showed that the Weld Metal's hardness (WM) was the highest, followed by the Heat-Affected Zone (HAZ) and BM. The welding experiment that used three variations in heat input demonstrated that higher heat input lowered the hardness of the weld joint. The microstructure observation results around the fusion line demonstrated the presence of step and ditch structures. The ditch structure indicates intergranular corrosion.
A study on optimal parameter combinations for austempered ductile iron Herry Oktadinata; Dewin Purnama; Rizal Nurdian Hamzah; Agung Slamet Apriyan
Jurnal Polimesin Vol 22, No 3 (2024): June
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v22i3.5001

Abstract

Nodular cast iron possesses a spherical graphite shape and exhibits mechanical properties closely resembling those of steel after heat treatment. The austempering method provides a means of enhancing the mechanical properties of nodular cast iron. This study aimed to investigate the optimal parameter combinations for Austempered Ductile Iron (ADI). The experiments involved varying the austenitization temperature and austempering time. Multiple tests were conducted to analyze the effects of austenitization temperature and tempering time on the microstructure, hardness, and impact toughness. The experimental samples were obtained from Y-block nodular cast iron austenitized at 850, 900, and 950°C for 90 min in an electric furnace. Subsequently, they were quenched in a salt bath at a temperature of 350°C and held for 60, 90, and 120 minutes before being cooled to room temperature. Mechanical tests and microstructure observations were performed on both the as-cast sample and after austempering. The microstructure was observed using an optical microscope before and after the etching. The research findings indicated that austempering increases the hardness and impact toughness of nodular cast iron. The highest hardness (46.8 HRC) was achieved from a parameter combination of an austenitization temperature of 850°C and an austempering time of 90 minutes. This particular sample also exhibited a relatively higher impact energy (3.8 J) compared to the others. The results of this study suggest that the austenitization temperature and tempering time exert an influence on the mechanical properties.
Analysis of the effect of welding sequence and speed on the distortion of ASTM A36 joints by MIG method Dewin Purnama; Vika Rizkia; Vina Nanda Garjati
Jurnal Polimesin Vol 21, No 5 (2023): October
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jpl.v21i5.4134

Abstract

The welding process with the Metal Inert Gas (MIG) method often produces distortions that are detrimental to product quality, one of the factors that affect the characteristics of the welding results is heat input. The heat input provided in the welding process is influenced by arc current, arc voltage, and welding speed, besides that the welding sequence can also affect the distortion of thin plates due to welding on materials such as ASTM A36 plates. The welding process uses welding wire/electrode type AWS ER 70S-6 with a diameter of 1.0 mm, the welding parameters applied are: voltage of 22 Volts, current of 150 Amperes, DC + Current type (DCEP), the shielding gas used is 100% Argon with a flow rate of 15 liters per minute, horizontal welding position (1G), the amount of heat input is differentiated by changing the welding speed and the welding sequence used is the stepping stone method. The results of the study using ANOVA indicate that welding distortion increases with an increase in input heat, the repetition of welding sequences leads to greater distortion due to thermal stress, and the welding sequence and input heat have an influence of 80.4% in reducing distortion.
Studi perbandingan elektroda bawah air konvensional dan elektroda dengan modifikasi tambahan mg Hindami, Fahrizan Imam; Winarto, Winarto; Purnama, Dewin
Jurnal Mesin Nusantara Vol 6 No 1 (2023): Jurnal Mesin Nusantara
Publisher : Universitas Nusantara PGRI Kediri

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.29407/jmn.v6i1.18161

Abstract

The influence of water depth, microstructure, chemical composition, welding defects, and mechanical properties affect underwater welding. In addition, the determination of electrodes for underwater welding requires unique properties, including being able to cause arcing and slag to grow on the surface of metal deposits which can protect against the effects of oxides and low hydrogen solubility. The electrodes must meet the AWS D3.6M underwater welding specification standard. In this study, the steel plate material used in AH-36 and implemented for underwater wet welding by comparing two electrodes, namely E6013 with additional Mg modifications and Broco E70XX electrodes specifically for underwater wet welding, the other Mg on E6013 rutile electrodes with modification 1 ( 3% Mg) and Modification 2 (5% Mg). The welding method with a heat input of 1.5 kJ/mm with 130 A and 2.5 kJ/mm with 140 A is carried out at 5m. The radiographic test results showed that the welded specimens at a depth of 5m showed imperfect penetration defects. It may be due to the effect of significant pressure and higher cooling rate that the weld melt cannot penetrate completely into the parent material. The tensile test results also showed an insignificant increase in the strength of the underwater welding, and the elongation was quite significant. Occurs at the E6013 electrode with modification 1 (3% Mg) and Modification 2 (5% Mg). The increase is not too significant. Penetration is not perfect. Due to significant pressure and a higher cooling rate, the molten weld cannot penetrate completely into the parent material. However, for testing the Broco E70XX electrode where there is no change in microstructure, such as electrodes modified with magnesium where only grain growth occurs, and there is Spheroidite which makes the microstructure related to mechanical properties, namely ductile.
Electric Vehicle Conversion Study for Sustainable Transport Zainuri, Fuad; Hidayat Tullah, Muhammad; Prasetya, Sonki; Susanto, Iwan; Purnama, Dewin; Subarkah, Rahmat; Ramiati, Tia; Widiyatmoko; Noval, Rahmat
Recent in Engineering Science and Technology Vol. 1 No. 02 (2023): RiESTech Volume 01 No. 02 Years 2023
Publisher : MBI

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.59511/riestech.v1i02.15

Abstract

The conversion of conventional motor vehicles to electric vehicles has become a popular choice in an effort to reduce greenhouse gas emissions and air pollution from transportation. Electric vehicle conversion involves replacing a gasoline or diesel engine with an electric motor and a reinstalled battery. In this paper, we cover the basics of electric vehicle conversion, conversion methods, and trial results of converted electric vehicles. We also discuss the benefits and challenges of converting to electric vehicles. Some keywords related to this topic include: electric vehicles, vehicle conversion, electric motors, batteries, sustainable transportation.
PELAPISAN ALUMINIUM DENGAN PROSES ANODISASI MULTIWARNA UNTUK APLIKASI KOMPONEN DEKORATIF SECARA PRAKTIS Dewin Purnama; Vika Rizkia
Jurnal Poli-Teknologi Vol. 11 No. 3 (2012)
Publisher : Politeknik Negeri Jakarta

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (389.27 KB) | DOI: 10.32722/pt.v11i3.461

Abstract

Abstract Anodizing of aluminum is an environmental friendly process and can be done with a relatively low cost, but the resulting product has a good surface appearance and a protective oxide layer. The purpose of this research is to produce alumina oxide layer in accordance with the criteria and the protective layer can be applied to coloring in the process further and to determine the effect of changes in temperature and voltage to the aluminum oxide layer formation and pore formation for dyeing in a solution of phosphoric acid (H3PO4). Preparation of porous anodic alumina layer is done through anodizing process with a set of processes and variables such as type and composition of electrolyte, voltage and current density, temperature process in order to obtain honeycomb structures with pore sizes in the scale of micrometers or nanometers. As an innovation, the process followed by a staining using inorganic dyeing with multicolored technique. Expectations from this research were obtained decorative aluminum coating method that can be applied practically. The results showed that the increasing dip temperature and the applied voltage will reduce the thickness of the oxide layer formed and then the higher the temperature applied to the anodizing process will result in larger pore sizes are formed on the oxide layer and the resulting pore size affects the intensity of color that occurs Keywords :Anodizing, Aluminum Oxide, Pore Diameter, Thickness --------------------------------------------------------------------- Abstrak Proses anodisasi aluminium merupakan proses yang ramah lingkungan dan dapat dilakukan dengan biaya yang relatif murah, namun produk yang dihasilkan mempunyai penampilan permukaan cukup baik serta memiliki lapisan oksida yang protektif. Tujuan penelitian ini adalah untuk menghasilkan produk lapisan oksida alumina yang sesuai dengan kriteria lapisan protektif dan dapat diaplikasikan untuk pewarnaan dalam proses lebih lanjut serta untuk mengetahui pengaruh perubahan temperatur dan tegangan terhadap pembentukan lapisan aluminum oxide dan pembentukan pori untuk pewarnaan hasil proses anodisasi dalam larutan asam fosfat (H3PO4). Pembuatan lapisan anodic porous alumina dilakukan melalui proses anodisasi dengan mengatur proses dan variable seperti jenis dan komposisi elektrolit, tegangan dan rapat arus, temperatur proses agar didapat struktur honeycomb dengan ukuran pori yang berskala mikrometer atau nanometer. Sebagai inovasi, proses dilanjutkan dengan pewarnaan menggunakan inorganic dyeing dengan teknik multiwarna. Diharapkan dari penelitian ini diperoleh metode pelapisan aluminium dekoratif yang dapat diterapkan secara praktis. Hasil penelitian menunjukan bahwa semakin meningkatnya temperatur celup dan tegangan yang diberikan akan menurunkan ketebalan lapisan oksida yang terbentuk. Kemudian semakin tinggi temperatur yang diaplikasikan pada proses anodisasi akan mengakibatkan ukuran pori yang semakin besar yang terbentuk pada lapisan oksida dan ukuran pori yang dihasilkan mempengaruhi intensitas warna yang terjadi. Kata kunci : Anodisasi, Aluminium Oksida, Diameter Pori, Tebal Lapisan
Co-Authors Agung Slamet Apriyan Debby Laksana Anugrah Fuad Zainuri, Fuad Herry Oktadinata Hidayat Tullah, Muhammad Hindami, Fahrizan Imam Iwan Susanto Muslimin Muslimin Noval, Rahmat Nur Citra Wahyudianti Patricia Laetitia Rahmat Subarkah Ramiati, Tia Rizal Nurdian Hamzah Rochsigit Nugroho Ryan Nugraha Seto Tjahyono Sonki Prasetya Vika Rizkia Vina Nanda Garjati Widiyatmoko Winarto Winarto Zulfikar Mutaqin