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EFEK GETARAN PADA PENGELASAN ALUMINUM 5083 H112 MENGGUNAKAN PROSES LAS GAS METAL ARC WELDING (GMAW) TERHADAP POROSITAS Rohmat, Imam Khoirul; Winarto, Winarto
Jurnal Teknologi Terapan Vol 4, No 2 (2018): Jurnal Teknologi Terapan
Publisher : P3M Politeknik Negeri Indramayu

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (871.661 KB) | DOI: 10.31884/jtt.v4i2.126

Abstract

5083 series aluminum magnesium is widely used for marine industrial. It is caused aluminum has high specific strength and good corrosion resistance. However, at process of welding many of porosity occured in the aluminum and it decrease the mechanical properties especially in HAZ (Heat Affected Zone). At casting process of aluminum, porosity could reduce by giving vibration. So, this method is tried to be applicated for welding of aluminum due to welding is a miniature of casting. Tensile test, hardness test, metallography test, and image analysis are technique to characterize the effect. As a result, vibration is not really affected the amount of porosity that occurred. But for hardness it is influenced especially for ER 4043 filler where the vibrated specimens have a higher hardness. The higher average result of tensile test for ER 5356 filler obtained at unvibrated specimens with the value is 231 MPa and for ER 4043 filler the higher average result obtained at vibrated specimen, the value is 226 MPa.
EFEK GETARAN PADA PENGELASAN ALUMINUM 5083 H112 MENGGUNAKAN PROSES LAS GAS METAL ARC WELDING (GMAW) TERHADAP POROSITAS Imam Khoirul Rohmat; Winarto Winarto
Jurnal Teknologi Terapan Vol 4, No 2 (2018): Jurnal Teknologi Terapan
Publisher : P3M Politeknik Negeri Indramayu

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (871.661 KB) | DOI: 10.31884/jtt.v4i2.126

Abstract

5083 series aluminum magnesium is widely used for marine industrial. It is caused aluminum has high specific strength and good corrosion resistance. However, at process of welding many of porosity occured in the aluminum and it decrease the mechanical properties especially in HAZ (Heat Affected Zone). At casting process of aluminum, porosity could reduce by giving vibration. So, this method is tried to be applicated for welding of aluminum due to welding is a miniature of casting. Tensile test, hardness test, metallography test, and image analysis are technique to characterize the effect. As a result, vibration is not really affected the amount of porosity that occurred. But for hardness it is influenced especially for ER 4043 filler where the vibrated specimens have a higher hardness. The higher average result of tensile test for ER 5356 filler obtained at unvibrated specimens with the value is 231 MPa and for ER 4043 filler the higher average result obtained at vibrated specimen, the value is 226 MPa.
Analisis Multiple Repair Pada Material Baja Karbon SA 333 Grade 6 Dengan Proses GTAW Terhadap Kekerasan, Ketangguhan, Dan Struktur Mikro Moh. Syaiful Amri; Yudi Eko Suyono; Imam Khoirul Rohmat
INOVTEK POLBENG Vol 12, No 1 (2022): INOVTEK VOL.12 NO.1 2022
Publisher : POLITEKNIK NEGERI BENGKALIS

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.35314/ip.v12i1.2309

Abstract

Dalam industri minyak dan gas, salah satu material yang digunakan adalah pipa baja carbon steel SA 333 Grade 6. Proses repair pada sambungan pengelasan sangat dihindari karena akan mengakibatkan kerusakan atau perubahan sifat mekanik. Dalam penelitian ini akan menggunakan 4 variasi yaitu tanpa repair,1x repair, 2x repair, 3x repair. Menggunakan test coupon pipa 2” SCH 160 dengan desain sambungan single bevel dan proses repair dilakukan setengah dari ketebalan material. Hasil uji mikro menghasilkan ukuran butir yang semakin kecil seiring dengan meningkatnya jumlah repair. Jumlah repair akan meninggkatkan persentase fasa pearlite di daerah HAZ.  Hasil uji kekerasan menghasilkan nilai rataan kekerasan tertinggi pada daerah HAZ dengan tanpa repair 163.73 HVN, 1x repair 167.04 HVN, 2x repair 169.38 HVN, 3x repair 177.67 HVN. Hasil uji ketangguhan menghasilkan nilai rataan pada weld metal dengan tanpa repair 102.3 joule, 1x repair 101.33 joule, 2x repair 95 joule, dan 3x repair 88.66 joule. Nilai ketangguhan pada daerah HAZ dengan tanpa repair 149 joule, 1x repair 148.6 joule, 2x repair 146 joule, dan 3x repair 145 joule. Dari hasil tersebut disimpulkan bahwa semakin meningkatnya jumlah repair akan menaikkan nilai kekerasan tetapi akan menurunkan nilai ketangguhan dari sambungan pengelasan dan semuanya memenuhi keberterimaan yang diijinkan.
Pemenuhan Kebutuhan Alat Pemadam Api Ringan Pada UMKM “Pentol Gilaaa” Surabaya Mochamad Yusuf Santoso; Aulia Nadia Rachmat; Fitri Hardiyanti; Imam Khoirul Rohmat; Ahmad Erlan Afiuddin; Mey Rohma Dhani
Surya Abdimas Vol. 6 No. 1 (2022)
Publisher : Universitas Muhammadiyah Purworejo

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.37729/abdimas.v6i1.1581

Abstract

Usaha Mikro, Kecil dan Menengah (UMKM) menjadi salah satu penyangga perekonomian Indonesia. Meski peran UMKM bagi perekonomian negara sangat besar, salah satu tantangan yang dihadapi UMKM adalah bagaimana meningkatkan produktivitas, sekaligus di saat yang sama meningkatkan Keselamatan dan Kesehatan Kerja (K3) di tempat kerja. K3 tidak hanya perlu diterapkan oleh perusahaan besar atau sektor dengan potensi bahaya tinggi seperti konstruksi dan pertambangan, namun juga oleh UMKM. UMKM “Pentol Gilaaa” merupakan salah satu usaha kuliner yang menyajikan jajanan pentol modern di Surabaya. Seiring dengan berkembangnya pasar dan meningkatnya minat konsumen, proses produksi tidak lagi dilakukan pada skala rumah tangga. UMKM ini memiliki rumah produksi yang memiliki berbagai macam peralatan yang dapat menimbulkan potensi bahaya. Salah satu potensi bahaya yang timbul adalah kebakaran, karena digunakan kompor dalam proses produksi. Kegiatan pengabdian kepada masyarakat ini bertujuan untuk memenuhi kebutuhan Alat Pemadam Api Ringan (APAR) bagi UMKM kuliner “Pentol Gilaaa”. Kegiatan diawali dengan observasi rumah produksi, yang dilanjutkan dengan identifikasi bahaya kebakaran. Hasil observasi dan identifikasi bahaya kemudian dianalisis untuk menghasilkan rekomendasi jenis APAR dan penempatannya. Hasil rekomendasi yang dapat diberikan adalah tabung APAR yang cocok untuk digunakan yaitu APAR dengan media tepung kering (dry chemical). Hal ini karena potensi kebakaran yang terjadi tergolong kebakaran kelas A, B, dan C. Jumlah APAR yang dibutuhkan adalah empat buah untuk lantai 1 dan satu buah untuk lantai 2. Untuk penempatan APAR, diberikan rekomendasi berupa peta penempatan APAR. Tindak lanjut dari kegiatan ini dapat berupa pelatihan penggunaan dan pemeliharaan APAR yang benar.
PENGARUH JENIS ACTIVATED FLUX DAN VARIASI KUAT ARUS PADA PENGELASAN A-TIG DISSIMILAR MATERIAL TERHADAP KEDALAMAN PENETRASI, KEKERASAN, STRUKTUR MIKRO DAN LAJU KOROSI Imam Khoirul Rohmat; Moch Iqbal Ramadhan; Dika Anggara
Jurnal Teknologi Terapan Vol 8, No 2 (2022): Jurnal Teknologi Terapan
Publisher : P3M Politeknik Negeri Indramayu

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31884/jtt.v8i2.375

Abstract

The TIG welding process has shallow penetration. The addition of activated flux can increase the depth of penetration of the weld, which is called A-TIG welding, so this study to analyze the effect of the activated flux type and current on the depth of penetration, hardness, microstructure, and corrosion rate. This study used SUS 304 and A36 materials with a thickness of 6 mm which are welded using the A-TIG welding process with variations of activated flux Fe2O3, Cr2O3 and variations in the current strength of 100 amperes and 120 amperes. To find out the results of these variations, this study was tested by macro, hardness, microstructure, and corrosion rate tests. The results of the study on variations in the type of activated flux and variations in current resulted penetration depth of 3.6 mm found in activated flux Cr2O3 with 120 amperes and penetration depth in activated flux Fe2O3 with a value of 2.43 mm on 100 amperes. Then the highest hardness value was found in activated flux Fe2O3 and 120 amperes with a value of 471.48 HVN, and the lowest is in Cr2O3 ampere 100 with a value of 398.16.HVN. The micro test results in a phase change from pearlite, ferrite, and austenite to martensite in the weld metal. And to test the corrosion rate on activated flux Fe2O3 and a current of 120 amperes with a value of 0.24931 mm/year, the activated flux Cr2O3 and a current of 100 amperes with a value of 0.090114 mm/year.
ANALISIS HOLDING TIME POST WELD HEAT TREATMENT (PWHT) PADA PENGELASAN MATERIAL SA-213 GRADE T91 DENGAN SA-213 GRADE T22 UNTUK APLIKASI BOILER Imam Khoirul Rohmat; Moh. Syaiful Amri; Mohammad Miftachul Munir; Hendri Budi Kurniyanto; M. Habib Muzzakki
Jurnal Rekayasa Mesin Vol. 14 No. 1 (2023)
Publisher : Jurusan Teknik Mesin, Fakultas Teknik, Universitas Brawijaya

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21776/jrm.v14i1.1304

Abstract

Superheater is one of the boiler components that works to heat the saturated steam coming out of the steam drum, by utilizing hot gases from combustion. In this study using Gas Tungsten Arc Welding (GTAW) and using SA-213 grade T91 and SA-213 grade T22, these two materials require Post Weld Heat Treatment (PWHT). One of the crucial factors in PWHT is holding time, because holding time aims to obtain a homogeneous temperature and homogeneous microstructure and can affect the mechanical properties of the material. This research was conducted to find out how the effect of PWHT holding time on SA-213 grade T91 and SA-213 grade T22 materials on the microstructure and hardness values. The results of the micro test show that the dominance of pearlite and martensite will decrease with increasing holding time, there is also a difference in microstructure grain size that will increase with increasing holding time which is associated with a decrease in value. The test results show that the hardness value will decrease with increasing holding time, especially in the weld metal area, getting the highest hardness value on the weld metal is in the specimen with a holding time of 15 minutes with a hardness value of 237.67 HVN and the lowest hardness value is in the specimen with holding time 45 minutes which is 201.1 HVN.
ANALISIS PENGARUH VARIASI TEKANAN GAS DAN PERSENTASE KETEBALAN LAPISAN BOUNDING DAN COATING PADA PROSES REBUILD-UP MATERIAL BAJA AISI 1045 DENGAN METODE ARC SPRAY TERHADAP TINGKAT KEREKATAN ANTAR LAPISAN Fathani Adhitya Mamang; Bachtiar Bachtiar; Imam Khoirul Rohmat; Adri Fato
Jurnal Teknologi Terapan Vol 9, No 2 (2023): Jurnal Teknologi Terapan
Publisher : P3M Politeknik Negeri Indramayu

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.31884/jtt.v9i2.463

Abstract

Each engine component has the durability that can decrease and wear due to continuous friction. The thermal spray method is an alternative that is used. The type of thermal spray that is found in the industry is Arc Spray. However, the peeling of the coating metal with the substrate is one of the problems. In this study, the variables that have contributed to the peeling of the coating layer were taken. The variables compared are the total thickness of the bounding and coating layers of 1 mm with a percentage of 50% : 50% and 30% : 70%. Another variation is gas pressure of 2 Bar, 3 Bar and 4 Bar in rebuild-up process of AISI 1045. Specimens with thickness percentage of 30% : 70% have significant difference in tensile strength value compared to the thickness percentage of 50% : 50% with an average difference of 5.02 MPa; 4.8975 MPa and 3.29 MPa in specimens with a gas pressure of 2 bar; 3 bars; 4 bars. The influences of thickness of bound and top coat have percentage effect 21.12% on each layer. As the gas pressure increases, the bonding value is higher because the higher gas, the smaller porosity which is proved by microstructural tests.
Analysis of variations in the number of layers of hardfacing overlay ABREX 500 material on hardness,impact strength and microstructure with the SMAW process Moh. Syaiful Amri; Dika Anggara; Imam Khoirul rohmat; Hendri Budi Kurniyanto; Dika Septya Pradana
Journal of Welding Technology Vol 5, No 2 (2023): December
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jowt.v5i2.4286

Abstract

Hardfacing is a welding technique that functions to increase the surface hardness value of a material. Generally, hardfacing is done on low-carbon steel materials because low-carbon steel cannot be increased in hardness by heat treatment. For this reason, research will be carried out on the multilayer hardfacing process with the aim of obtaining optimal layer hardness. The methodology in this research is that multilayer hardfacing welding will be carried out consisting of 3 layers, 4 layers, and 5 layers, and each specimen has 2 buffer layer layers with E 309 electrodes for the hardfacing layer using HV 600 electrodes. This research reveals the influence of the number of layers of hardfacing on the hardness and toughness values. ABREX 500 material with a size of 150x150x10 mm was welded using the SMAW process using a current of 130 A. In this research, hardness and toughness tests were carried out. On test results. The base metal microstructure is dominated by a tempered martensite structure with a small amount of bainite and pearlite. In the structural area of the support layer, austenite and vermicular ferrite dominate. In the hardfacing layer area, austenite and vermicular ferrite, which are in dendritic form, dominate. The increase in hardness will occur significantly after hardfacing is carried out on the base metal. In a specimen, the more layers of hardfacing are added, the harder the material will be. The hardness of the specimen in 5 layers gets the most optimal value (higher) when compared with the hardness in 3 layers and 4 layers. In the 5-layer specimen, the resulting hardness value was 482.13 kgf/mm2, for the 4-layer specimen, the average value was 464.83 kgf/mm2, and in the 3-layer specimen, the hardness value was 444.13 kgf/mm2. For toughness testing, the highest toughness value was obtained, namely 1.32 (J/mm2) for the 3 layers specimen, compared to 4 layers with a toughness value of 1.25 (J/mm2) and 5 layer with a toughness value of 1.19 (J/mm2). The toughness value decreases as the hardness value increases.
Analysis of Bending Methods on BjTP 280 Roundbars on Hardness and Microstructure Adzin Hanif Muttaqin; Mohammad Miftachul Munir; Imam Khoirul Rohmat
Journal of Welding Technology Vol 5, No 2 (2023): December
Publisher : Politeknik Negeri Lhokseumawe

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30811/jowt.v5i2.4197

Abstract

Reinforcing steel or commonly called roundbars is a material that is often used in industry, this is because the material is strong and easy to find anywhere. Deformation has a relationship to hardness. The higher the deformation value, the higher the material hardness value, but this is inversely proportional to the grain change, where the greater the deformation, the smaller the grain size. This research aims to determine the hardness and microstructure values of cold bending and hot bending treatments. Research by carrying out cold bending and hot bending which is connected to roundbars material without BjTP 280 bending treatment with the SMAW welding process. The highest hardness value is shown in the HAZ area of the hot bending specimen with a hardness value of 239.97 HV with a fine and small microstructure so it has the highest hardness value.
Perbandingan PWHT dan Non PWHT pada Pengelasan Material SA-213 Grade T91 dengan SA-213 Grade T22 terhadap Struktur Mikro dan Kekerasan Imam Khoirul Rohmat; Moh. Saiful Amri; M. Habib Muzzakki; Hendri Budi Kurniyanto; Mukhlis Mukhlis; Moh. Miftachul Munir
Jurnal Rekayasa Mesin Vol 18, No 1 (2023): Volume 18, Nomor 1, April 2023
Publisher : Mechanical Engineering Department - Semarang State Polytechnic

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.32497/jrm.v18i1.4171

Abstract

Superheater adalah salah satu komponen boiler yang berfungsi untuk memanaskan uap jenuh yang keluar dari steam drum, material yang sering digunakan pada superheater adalah SA-213 grade T91 dan SA-213 grade T22, pada penelitian ini menggunakan proses pengelasan Gas Tungsten Arc Welding (GTAW). Kedua material yang digunakan wajib dilakukan proses PWHT, karena salah satu tujuan PWHT adalah menurunkan nilai kekerasan dan menyeragamkan struktur mikro. Penelitian ini bertujuan untuk mengetahui perbandingan PWHT dan tanpa PWHT pada material SA-213 grade T91 dan SA-213 grade T22 terhadap struktur mikro dan kekerasan. Hasil pengujian struktur mikro menunjukkan adanya pengurangan prosentase pearlite serta martensite dan adanya penambahan ukuran butir struktur mikro setelah PWHT. Pengujian hardness vickers menunjukkan adanya penurunan nilai kekerasan yang signifikan, khususnya pada daerah weld metal dan HAZ antara material tanpa PWHT dan PWHT. Didapatkan nilai kekerasan tertinggi pada weld metal SA-213 grade T91 tanpa PWHT dengan nilai kekerasan 376.70 HVN dan nilai terendah weld metal ada pada spesimen dengan holding time 45 menit yaitu sebesar 201.1 HVN.