PENGARUH MULTIPLE REPAIR WELDING PADA PENGELASAN GTAW DAN SMAW TERHADAP STRUKTUR MIKRO, FERRITE NUMBER, SIFAT MEKANIK DAN LAJU KOROSI PADA MATERIAL PIPA SA 312 TYPE 304L

Bimantoro, Panji Wahyu (2016) PENGARUH MULTIPLE REPAIR WELDING PADA PENGELASAN GTAW DAN SMAW TERHADAP STRUKTUR MIKRO, FERRITE NUMBER, SIFAT MEKANIK DAN LAJU KOROSI PADA MATERIAL PIPA SA 312 TYPE 304L. Diploma thesis, POLITEKNIK PERKAPALAN NEGERI SURABAYA.

Full text not available from this repository.

Abstract

ABSTRAK Proses pengelasan selalu ada resiko gagal dalam proses pengerjaannya maka diperlukan perbaikan atau repair, apabila kegagalan dilakukan berulang kali maka perlu dilakukan metode multiple repair welding. Multiple repair welding yang dilakukan membuat material terkena panas yang berulang-ulang dan akan menyebabkan terjadinya deformasi, perubahan metalurgi, tegangan thermal, dan perubahan struktur. Akibat terjadinya perubahan struktur maka sifat mekaniknya akan berubah. Pada penelitian tugas akhir ini menggunakan 3 variasi repair yang berbeda yaitu pengelasan yang tanpa di repair, pengelasan yang di repair 1x, dan pengelasan yang di repair 2x. Pada proses pengelasan menggunakan pengelasan kombinasi yaitu GTAW untuk root pass dan SMAW pada fill pass dan caping. Proses pengelasan ini dilakukan dengan beberapa prosedur pengelasan dan pengujian. Untuk material yang digunakan menggunakan material pipa SA 312 type 304L. Setelah proses pengelasan selesai dilakukan beberapa pengujian yaitu struktur mikro, uji ferrite number, uji tarik, uji lengkung dan uji laju korosi. Proses penelitian ini diketahui hasil struktur mikro terlihat bahwa semakin banyak proses multiple repair welding yang dilakukan, terlihat semakin banyak karbida krom yang terbentuk, semakin besar struktur pada fusion line dan HAZ. Hasil ferrite number yang terkandung pada spesimen tanpa repair memiliki ferrite number yang tinggi dibandingkan dengan spesimen yang di repair 1x dan repair 2x, dapat dilihat bahwa ferrite number akan berkurang apabila dilakukan multiple repair welding. Hasil uji tarik pada spesimen tanpa repair memiliki nilai kuat tarik yang lebih tinggi sebesar 512,20 MPa, dibanding dengan spesimen dengan repair 1x dan 2x sebesar 509,54 MPa dan 502,73 MPa. Hasil uji weight loss didapatkan hasil bahwa laju korosi terendah terdapat pada spesimen tanpa di repair yaitu sebesar 14,3152 mmpy, dan tertinggi terdapat pada spesimen yang di repair 2x yaitu sebesar 16,0447 mmpy. Jadi semakin banyak repair semakin tinggi pula nilai laju korosinya. Kata kunci: multiple repair welding, SA 312 Type 304L, pengelasan GTAW ABSTRACT In the process of welding, a risk of failure was commonly occurred at processing it. Therefore, it required improvement or repair. If it happened repeatedly, it was necessary to use multiple repair welding methods. Multiple repair welding which was done would make the material heated repeatedly and cause deformation, metallurgy changing, thermal stressing, and structure changing. As a result of the structure changing, it made the mechanical properties changed. This research used 3 different variations of repair theywere welding without repair, welding which was used 1x and 2x repair. In this welding process used two welding combinations they were GTAW for root pass and SMAW on filler pass and caping. The welding process was done by using welding procedure and testing. The material used was SA 312 type 304L pipe. After the process of welding finished, some tests were done they were the microstructure, ferrite number test, tensile test, bend test and corrosion rate test. The research process is known micro structure results seen that the more the process of multiple repair welding is done, it looks increase karbida chrome is formed, the major structures on the fusion line and HAZ. Results ferrite number contained in the specimen without repair has a ferrite number higher than the specimens in repair 1x and 2x repair, it can be seen that the ferrite number will be reduced when performed multiple repair welding. The results of tensile tests on specimens without repair has a tensile strength values were higher at 512.20 MPa, compared with specimens with 1x and 2x repair of 509.54 MPa and 502.73 MPa. The test results showed that the weight loss corrosion rate was lowest for the specimens without in repair in the amount of 14.3152 mmpy, and highest in specimens in repair 2x is equal to 16.0447 mmpy. So it can be concluded that the more material repaired, the higher of the corrosion rate. Keyword: multiple repair welding, SA 312 Type 304L, GTAW and SMAW welding

Item Type: Thesis (Diploma)
Subjects: T Technology > T Technology (General)
Divisions: Jurusan Teknik Bangunan Kapal > D4 Teknik Pengelasan
Depositing User: Unnamed user with email repository@ppns.ac.id
Date Deposited: 17 Sep 2018 02:47
Last Modified: 17 Sep 2018 02:47
URI: http://repository.ppns.ac.id/id/eprint/798

Actions (login required)

View Item View Item