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PENINGKATAN KEMAMPUAN PENGELASAN SMAW POSISI 2F PEMUDA KELURAHAN KOTO LUAR KECAMATAN PAUH PADANG Yetri, Yuli; Zulhendri; Yuliarman; Rosa, Yasmendra; Sukma, Rino ; Junaidi; Yusri
Bahasa Indonesia Vol 16 No 01 (2019): Sarwahita : Jurnal Pengabdian Kepada Masyarakat
Publisher : Lembaga Penelitian dan Pengabdian Kepada Masyarakat

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.21009/sarwahita.161.04

Abstract

The community service program carried out by the Mechanical Engineering Department, Padang State Polytechnic lecturer is an activity in order to fulfill the Tridarma of Higher Education for the 2018 budget year. The activity was held in the form of SMAW 2F welding improvement training for the youth of Koto Luar, Pauh sub-district, Padang. In this area, there are many high school graduates who have not dared to enter the real workforce because they feel they do not have sufficient skills to join the field workforce. On the other hand, the Koto Luar village is currently developing very fast, because there has been assimilation between migrants and indigenous people. Along with increasing population, of course also followed by the addition of living facilities. To synergize the increase in progress with its human resource capabilities, various knowledge and skills are needed, one of which is the electric welding skills knowledge of SMAW 2F. Its welding training was attended by 21 Koto Luar youths for 4 days at the Mechanical Engineering department workshop. Expected abilities after training, Koto Luar youths are able to properly weld 2F methods according to welding standards, so that later participants are expected to enter the world of welding work. After debriefing the participants can take part in the welding training well, so that they get the SMAW 2F welding certificate signed by the director of the Padang State Polytechnic. The welding enhancement training activity of SMAW 2F received positive support from the chairman of the Community Empowerment Agency (BPM) and village leaders, because this activity had long been wanted by the community. The Koto Luar community hopes that the training to improve SMAW 2F's welding ability for youth in Pauh Padang sub-district can be carried out continuously, because many young people are interested in SMAW's welding knowledge, the goal is to be able to open entrepreneurs and fill jobs around Lambung Bukit, Koto Luar , and Limau Manis Padang.
Pengaruh Penambahan Serbuk Gelatin Terhadap Sifat Mekanik Dan Biodegradabilitas Plastik Campuran Polietilen Tereftalat Bekas Dan Pati Sagu -, Resalina; Dt. Basa, Sri Mulyadi; Yetri, Yuli
Jurnal Fisika Unand Vol 2, No 1: Januari 2013
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jfu.2.1.%p.2013

Abstract

Telah dilakukan penelitian tentang pengaruh penambahan serbuk gelatin terhadap sifat mekanik dan biodegradabilitas plastik campuran polietilen tereftalat bekas dan pati sagu. Pada penelitian ini dibuat sampel dengan 4 macam variasi penambahan serbuk gelatin yaitu 0 g, 5 g, 10 g dan 15 g. Sampel tersebut dikubur selama 10 hari, 20 hari, 30 hari dan 40 hari. Kemudian dilakukan pengujian sifat mekanik (kuat lentur dan kuat tarik) dan biodegradabilitas dari sampel. Hasil menunjukkan bahwa serbuk gelatin kurang mempengaruhi kekuatan lentur sampel, nilai kuat lentur tertinggi dimiliki sampel tanpa penambahan serbuk gelatin. Nilai kuat tarik tertinggi dimiliki sampel dengan penambahan serbuk gelatin sebanyak 5 g, yaitu sebesar 505,411 N/mm2. Sampel yang paling cepat terdegradasi adalah sampel dengan penambahan serbuk gelatin sebanyak 15 g.
Pengendalian Laju Korosi pada Baja API 5L Grade B N Menggunakan Ekstrak Daun Gambir (Uncaria gambir Roxb) Murti, Eri Aidio; Handani, Sri; Yetri, Yuli
Jurnal Fisika Unand Vol 5, No 2 (2016)
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jfu.5.2.172-178.2016

Abstract

Telah dilakukan penelitian tentang pengendalian laju korosi pada baja API 5L Grade B N menggunakan ekstrak daun gambir dengan konsentrasi 0; 0,5; 1,0; 1,5 dan 2,0%. Medium korosif yang digunakan adalah NaCl dan H2SO4 1 M. Empat sampel direndam dalam medium korosif tanpa inhibitor, 4 sampel direndam pada medium korosif dengan penambahan inhibitor dan 4 sampel direndam dalam larutan inhibitor selama 24 jam, kemudian direndam di dalam medium korosif. Lama perendaman bervariasi yaitu 1, 5, 10 dan 15 hari Metode yang digunakan adalah metode kehilangan berat untuk menentukan laju korosi dan nilai efisiensi. Laju korosi berkurang dengan kenaikan konsentrasi inhibitor. Nilai efisiensi tertinggi mencapai 94,65% pada medium korosif NaCl 1 M dan 89,79% pada medium korosif H2SO4 1 M dengan kenaikan konsentrasi inhibitor 2%. Hasil foto SEM permukaan baja memperlihatkan permukaan baja dengan penambahan ekstrak daun gambir mengalami korosi lebih sedikit.Kata kunci: baja API 5L Grade B N, efisiensi inhibisi, ekstrak daun gambir, inhibitor, laju korosi
Pengaruh Galvanisasi Terhadap Struktur Mikro Batang Baja Karbon Rendah Yetri, Yuli
JURNAL R & B Vol 1, No 2 (2001)
Publisher : JURNAL R & B

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Abstract

The aim of galvanizing in steel to improve power resistance corrotion ard resistance to wear out, for example : component automotive. But galvanizing can be hydrogen atom diffused into low carbon steel during galvanizing. The proces for drop out hidrogen to surface, after galvanizing was baked at ternperature 200 C during 15 hours, 48 hours and 65 hours. And material was analyzed with microscope optic and hardness test. The conclution cf analizing not influence with baking at temperatur 200 C because temperatur baking under transformation temperature. The increase of  baking time, hardness of materials decrease and consentration hydrogen also decrease.
Pengerasan Baja Lunak (Mild Steel) Dengan Media Pendingin Air dan Minyak Pelumas Sae 10 Yetri, Yuli; Nusyirwan, Nusyirwan
JURNAL R & B Vol 3, No 1 (2003)
Publisher : JURNAL R & B

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Abstract

Mild stell is low carbon steel  contain 0,3 % carbon, for example ST 37. the mechanic properties hardness, tensile strength, tougness etc depend on carbon contain. In realty the weakness of ST37 are difficult to hardening. To increase hardness of mild steel are done heat treatment at 800 °C and 100 °C temperature. After that are hold for 30 minutes and then are quenched in oil SAE 10 and water for 15 minutes. For measuring hardnees of sampl are Brinell Methode. The result of testing the sample are obtained data like this, for heating 800 °C quench water the hardnees increase about 23,23 % and quench oil SAE the hardness decrease 28,54 %. When are heated 1000 °C the hardness both of sample decrease finally, in this experiment can be taken conclusion that mild steel are difficult to be hardening.
Perencanaan Perawatan Mesin Pengupas Kulit Pinang Erizal, Ihsan Putra; Yetri, Yuli; Nusyirwan, Nusyirwan
Jurnal Teknik Mesin Vol 11 No 1 (2018): Jurnal Teknik Mesin
Publisher : Politeknik Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30630/jtm.11.1.173

Abstract

Planner engine maintenance is an important thing to streamline the production process. Care planning for areca nut peeler has been carried out which includes the engine frame, electric motor, pulleys, V-belts, reservoirs, and spindle shaft. These components are expected to work optimally so that satisfying results are obtained. The care of the areca peeling machine consists of preventive treatments, repair treatments, total treatments. Preventive care consists of cleaning, lubrication and periodic checks. Repair treatments include blade maintenance, bearing maintenance, pulley care and belt. While total maintenance is carried out after the engine has been operating long enough. The results of treatment planning are made in the form of a treatment table. While the results of the maintenance process that has been done by the machine can operate properly and can produce maximally.
Pengendalian Laju Korosi Baja St-37 Dalam Medium Asam Klorida dan Natrium Klorida Menggunakan Inhibitor Ekstrak Daun Teh (Camelia Sinensis) Mitra Sari, Desi; Handani, Sri; Yetri, Yuli
POLI REKAYASA Vol 8, No 2 (2013)
Publisher : POLI REKAYASA

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Abstract

A research  to control corrosion rate of St-37 steel in acid chloride and sodium chloride medium using tea leaf (Camellia sinensis) extract inhibitor has been done. The method used is potentiodynamic to see the value of the corrosion current and weight loss method for corrosion rate.. Corrosive medium used were HCl 3% and NaCl 3%. The concentration of the extract used range from 1%-10% and the immersion time is four days. The results showed that the corrosion rate was greatest in the corrosive medium without addition of inhibitors, whereas the corrosion rate decreases with the addition of inhibitors, it is also evident from the results of the Tafel plot shows Icor impairment. The greater the concentration of inhibitor that is used the lower the corrosion rate. Greatest efficiency values both  for medium corrosive ​​obtained at inhibitor concentrations of 10%, 86,3% in HCl and 92% in NaCl. This shows that tea leaves extract inhibitor is very efficient in controlling the rate of corrosion in HCl and NaCl medium. From the optical photograph  analysed on the surface morphology of St-37 steel showed that the addition of tea leaf extract suffered less corrosion.
PENGARUH KONSENTRASI INHIBITOR EKSTRAK DAUN KAKAO (Theobroma cacao) TERHADAP LAJU KOROSI BAJA HARDOX 450 Malfinora, Anike; Handani, Sri; Yetri, Yuli
Jurnal Fisika Unand Vol 3, No 4: Oktober 2014
Publisher : Universitas Andalas

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.25077/jfu.3.4.222-228.2014

Abstract

ABSTRAKTelah dilakukan serangkaian uji korosi dan analisis struktur mikro terhadap baja Hardox 450.  Penelitian ini dilakukan dengan menggunakan medium korosif H2SO4 3% dan Na2SO4 3%.  Metode yang digunakan adalah metode weight loss untuk pengukuran laju korosi dan metode potensiodinamik untuk melihat nilai arus korosi beserta potensial korosi.  Baja direndam di dalam medium korosif dengan penambahan dan tanpa penambahan inhibitor.  Variasi konsentrasi inhibitor yang digunakan adalah dari 1% hingga 10% dengan lama perendaman lima hari.  Hasil penelitian menunjukkan bahwa dari variasi konsentrasi yang diberikan laju korosi terbesar terjadi pada baja tanpa penambahan inhibitor, sedangkan laju korosi berkurang dengan penambahan inhibitor, terlihat dari kurva Tafel yang menunjukkan penurunan Ikorosi.  Semakin besar konsentrasi inhibitor yang ditambahkan maka nilai laju korosi akan semakin menurun dan nilai efisiensi inhibisi korosi semakin tinggi.  Nilai efisiensi terbesar didapatkan pada penambahan konsentrasi inhibitor 10%, untuk medium korosif H2SO4 mencapai 63,89% dan untuk medium Na2SO4 mencapai 56,61%.  Hal ini menunjukkan bahwa inhibitor ekstrak daun kakao efisien dalam mengendalikan laju korosi dalam medium H2SO4 dan Na2SO4.  Dari analisis foto optik morfologi permukaan baja Hardox 450 memperlihatkan permukaan baja dengan penambahan ekstrak daun kakao mengalami korosi lebih sedikit.Kata kunci : laju korosi, inhibitor, efisiensi, weight loss, potensiodinamikAbstractThe corrosion test and microstructure analysis of Hardox 450 steel have been done.  This research was performed using H2SO4 3% and Na2SO4 3% corrosive mediums.  The method used were weight loss for measuring the corrosion rate and potentiodynamic method to see the value of corrosion current and corrosion potential.  Steel immersed in the corrosive medium with the addition and without addition of inhibitors.  Concentration variation of inhibitor used was from 1% to 10% with five days immersion time.  The result based from concentration variation was used showed that the corrosion rate occured in the steel without the addition of inhibitors, whereas the corrosion rate decreases with the addition of inhibitors, by the Tafel curves showed a decreases Icor.  The greater concentration of the inhibitor is added then the value of corrosion rate will lower and corrosion inhibition efficiency will increase.  Greatest efficiency values both for medium corrosive obtained at inhibitor concentration 10%, 63,89% in H2SO4 and 56,61% in Na2SO4.  It shows that the cocoa leaf extract inhibitor is efficient in controlling corrotion rate in H2SO4 and Na2SO4 medium corrosive.  From the optical photograph analysed on the surface morphology of Hardox 450 steel showed that the addition of cocoa leaves extract suffered less corrosion.Keywords: corrosion rate, inhibitor, efficiency, weight loss, potentiodynamic
EFFISIENSI INHIBISI KOROSI BAJA LUNAK DALAM MEDIA ASAM DENGAN INHIBITOR EKSTRAK KULIT BUAH KAKAO (Theobroma cacao) Yetri, Yuli; Emriadi, E; Jamarun, Novesar; Gunawarman, G
Jurnal Riset Teknologi Pencegahan Pencemaran Industri Vol 7, No 2 (2016)
Publisher : Kementerian Perindustrian

Show Abstract | Download Original | Original Source | Check in Google Scholar | Full PDF (3491.834 KB) | DOI: 10.21771/vol7no2tahun2016artikel1378

Abstract

Efek inhibisi korosi dan sifat-sifat adsorpsi oleh ekstrak kulit buah kakao (Theobroma cacao)  pada baja lunak (mild steel) dalam larutan asam 1,5M HCl telah dipelajari menggunakan teknik konvensional metode berat hilang pada variasi waktu, konsentrasi dan suhu. Parameter-parameter termodinamika seperti energi aktivasi, entalpi, entropi dan perubahan energi bebas dihitung. Polarisasi elektrokimia telah dievaluasi untuk memastikan jenis inhibitor. Spektra infrared dan GCMS dilakukan untuk mengetahui senyawa ekstrak yang berperan  dalam proses inhibisi. Morfologi permukaan sampel diamati dengan menggunakan scanning electro microscopy dengan  energy dispersive X-ray spectroscopy (SEM-EDX) . Keseluruhan hasil penelitian menunjukkan bahwa ekstrak polar kulit buah coklat  dapat digunakan sebagai inhibitor korosi yang efektif pada baja karbon di lingkungan 1,5M HCl dengan pencapaian efisiensi  inhibisi   terkorosi sebesar 96.26% (weight loss) dan 92.08% (Tafel) pada konsentrasi ekstrak 2,5% selama768 jam. Mekanisme inhibisi adalah  adsorpsi chemiadsorpsi berdasar tingginya nilai entalpi dan energi bebas.Effisiensi Inhibisi diketahui meningkat dengan peningkatan konsentrasi dari ekstrak serta menurun dengan peningkatan suhu. Kurva polarisasi menunjukkan inhibitor ini berperilaku sebagai inhibitor campuran dengan dominan pada inhibisi katodik. Ekstrak diadsorpsi oleh permukaan mild steel  mengikuti model adsorpsi isotherm Langmuir. Kondisi permukaan mild steel menunjukan terjadinya adsorpsi di permukaan membentuk lapisan tipis di permukaan logam. Penambahan ekstrak kulit buah kakao ke dalam larutan HCl sangat efektif untuk mengurangi serangan korosi di permukaan mild steel.  Kata kunci: Korosi, Inhibitor, Theobroma cacao, Mild steel, Potensiodinamik Corrosion Inhibition Efficiency Mild Steel in Acid Media with Inhibitor Peels Extract of Cacao (Theobroma cacao)ABSTRACT Inhibition and adsorption properties of Theobroma cacao peel polar extract addition on corrosion inhibition efficiency of 0.3%C mild steel in hydrochloric acid solution for various exposuring time, extract concentration and working temperature were investigated using weight loss test method. Electrochemical polarization test was also conducted to confirm the effectiveness of inhibition. Infrared spectrum of the samples was also evaluated to reveal compounds of the extract which controll the inhibition process. Morphology and local composition of sample surfaces were respectively examined by scanning electron microscope  (SEM) and energy dispersive X-ray spectroscopy (EDX). Thermodynamic parameters such as energy activation, enthalpy, entropy and change in the free energy were then determined using related data. The results show that the inhibition efficiency increases significantly up to 96.3% (by weight loss method) and 92.08% (Tafel) with the increase of TCPE content. The optimum efficiency is obtained at extract concentration of 2,5% for exposuring time of 768h. However, the efficiency decreases slightly with increasing working temperature in the range of 303K-323K. The polarization curve shows the inhibitor behaves as a mixed inhibitor with the dominant cathodic inhibition. The adsorption model is found to obey Langmuir adsorption isotherm. Surface condition is  improved due to the adsorption and then formation of thin layer film protection in the surface of the steel. The addition of extract of cacao peels into HCl is effective to minimize corrosion attack on the mild steel. Key words: Corrosion, inhibitor, Theobroma cacao peel, Mild steel, Potensiodinamic
Pembuatan Cetakan Pasir Dan Proses Pemesinan Untuk Komponen Blok Pompa Pada Mesin Pompa Air Merk Matrix Model Mtx-22c Firdaus, Firdaus; Rakiman, Rakiman; Effiandi, Nota; Yetri, Yuli
Jurnal Teknik Mesin Vol 11 No 2 (2018): Jurnal Teknik Mesin
Publisher : Politeknik Negeri Padang

Show Abstract | Download Original | Original Source | Check in Google Scholar | DOI: 10.30630/jtm.11.2.166

Abstract

Reverse Engineering (RE) is a process in manufacturing that aims to reproduce or recreate existing models, either components, sub-components, or products without using existing design documents or working drawings. Through this reverse engineering idea, the process of making the Pump Block component is started with making part and mold design, making sand casting, then finished with machining processes. The machining process that is carried out is the turning process, the milling process, and the drilling process which is assisted by using jigs and fixture to make it easier on finishing the Pump Block parts in the machining process. By using the processes, so it is produced the similar pump block that is resemble with desired original object.