Pengaruh Variasi Holding Temperature dan Holding Time Pada  Post Weld  Heat Treatment  Terhadap Struktur Mikro dan   Distribusi  Kekerasan   Hasil  Pengelasan  Bisclad   600 dengan Metode SMAW di PT. Holcim Indonesia

One of the welding methods that is widely used today because it is easier to operate, more practical in its use, can be used for all welding positions and more efficient is called Shield Metal Arc Welding (SMAW). In this welding, the base metal and filler metal will experience thermal cycles which lead to local heating and cooling processes resulting in residual stress and distortion in the material. This residual stress must be removed because it causes a decrease in the mechanical properties of the material. The most widely used method is the thermal method that is by Post Weld Heat Treatment (PWHT). The success of The post-weld heat treatment in removing residual stresses in PWHT is influenced by the holding time. This study aims to examine the effect of holding time on heat treatment, on the weld toughness of steel. In this study, the type of welding used was SMAW welding, the material used was steel AISI 4130, the electrodes used were LB-7018-1 standard application and AWS classification A5.1 E7018-1. The test holding temperature is 650oC. The holding time of testing uses three variables, namely: 2.5 hours, 4.5 hours, 6.5 hours. The Impact testing is done by the Charpy method. From this study, the influence of holding time variation on PWHT holding temperature on the weld strength of AISI 4130 steel was obtained.

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The Effect of Holding Time under Heat Treatment on the Properties of T92 Steel Welding Joint

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.1079-1080.7 ◽

2014 ◽

Vol 1079-1080 ◽

pp. 7-12

Author(s):

Dong Xu Yang ◽

Lu Yang ◽

An Guo Huang

Keyword(s):

Heat Treatment ◽

Post Weld Heat Treatment ◽

Holding Time ◽

Welding Joint ◽

Heat Resistant Alloy ◽

Fine Grain ◽

Joint Property ◽

Tempering Time ◽

Martensite Structure ◽

Weld Heat

This article describes the welding joint property of ferrite heat-resistant alloy steel T92 by taking tungsten inert gas (TIG) welding measures before post weld heat treatment on 760°C with holding time of 0,2,4 hours. Test data were analyzed in relation to microstructure,tensile and impact properties and hardness distribution on the welding joint,then the effect of holding time under post weld heat treatment on properties of joints can be investigated.The results demonstrated that micro-hardness in the weld and tensile strength decreased with tempering time prolonging, while impact toughness increased with the extension of tempering time. The untempered martensite in form of needle was coarse in the joint. With the extension of holding time under tempering, the martensite structure obtains fine grain and the lath characteristic becomes obvious. It can be found that the segregation of carbides in base metal occurred and the content of ferrite increased with the extension of holding time under tempering.

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Effect of Simulated Post-Weld Heat Treatment on the Mechanical Properties and Microstructure of P-No. 1 Carbon Steels

Volume 6B: Materials and Fabrication ◽

10.1115/pvp2018-84605 ◽

2018 ◽

Author(s):

Yongjoon Kang ◽

Seung-Gun Lee ◽

Gi-Dong Kim ◽

Sang-Hoon Lee ◽

Sang-Woo Song ◽

...

Keyword(s):

Mechanical Properties ◽

Heat Treatment ◽

Carbon Steel ◽

Carbon Steels ◽

Post Weld Heat Treatment ◽

Steel Plates ◽

Lateral Expansion ◽

Division 1 ◽

Holding Temperature ◽

Weld Heat

The effect of simulated post-weld heat treatment (PWHT) on the mechanical properties and microstructure of P-No. 1 materials was investigated and the suitability of the exemption requirements of simulated PWHT as specified in ASME Section III Division 1 Subsection NX-2211 was evaluated. SA-516 Gr. 60 and 70 carbon steel plates and SA-106 Gr. B carbon steel pipe were employed, and the materials were subjected to the simulated PWHT with holding temperatures of 610, 650, 690, and 730 °C for 8 hours. Both the tensile strength and lateral expansion of the materials tested in this study showed a tendency to decrease with increasing holding temperature of the simulated PWHT. In some cases, the materials after the simulated PWHT cannot satisfy those mechanical requirements.

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Pengaruh Post Weld Heat Treatment (Pwht) dengan Pemanas Induksi Terhadap Sifat Mekanik dan Struktur Mikro Sambungan Las Shield Metal Arc Welding (Smaw) pada Pipa API 5l X52

ROTASI ◽

10.14710/rotasi.19.3.117-124 ◽

2017 ◽

Vol 19 (3) ◽

pp. 117 ◽

Cited By ~ 1

Author(s):

Gunawan Dwi Haryadi ◽

Rifky Ismail ◽

Mahmuda Haira

Keyword(s):

Heat Treatment ◽

Weld Metal ◽

Acicular Ferrite ◽

Arc Welding ◽

Post Weld Heat Treatment ◽

Holding Time ◽

Metal Arc Welding ◽

Weld Heat

Saluran perpipaan telah digunakan sebagai salah satu metode yang paling praktis dan berharga murah untuk transportasi minyak dan gas. Penyambungan pipa sendiri dilakukan dengan proses pengelasan. Pada pengelasan memunculkan efek pemanasan setempat dengan temperatur tinggi yang menyebabkan logam mengalami ekspansi termal maupun penyusutan saat pendinginan. Hal itu menyebabkan terjadinya tegangan sisa, perubahan struktur mikro, kekerasan dan ketangguhan yang berbeda-beda pada tiap-tiap daerah konstruksi. Salah satu cara untuk memperbaiki hal tersebut yaitu dengan cara melakukan post weld heat treatment (PWHT). Penelitian ini bertujuan untuk mengetahui pengaruh PWHT terhadap sifat mekanik dan struktur mikro pada pengelasan shield metal arc welding (SMAW). PWHT dilakukan dengan menggunakan alat pemanas induksi pada temperatur 400ºC, 500 ºC 600 ºC, 700 ºC dan 800 ºC dengan holding time selama 15 detik dan didinginkan di udara terbuka. Selanjutnya dilakukan pengujian impak, kekerasan dan struktur mikro untuk mengetahui pengaruh PWHT yang dilakukan. Dari hasil pengujian impak dan kekerarasan diketahui bahwa semakin tinggi temperature PWHT maka semakin tinggi juga nilai ketangguhan dan semakin menurun nilai kekerasannya. Dan dari pengamatan struktur mikro daerah weld metal PWHT mengakibatkan terjadinya peningkatan jumlah struktur acicular ferrite dan penurunan jumlah struktur widmanstatten ferrite.

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Residual Stress Relief in Post-Weld Heat Treatment

Volume 6: Materials and Fabrication, Parts A and B ◽

10.1115/pvp2008-61210 ◽

2008 ◽

Cited By ~ 1

Author(s):

Pingsha Dong ◽

Jeong K. Hong

Keyword(s):

Heat Treatment ◽

Residual Stress ◽

Stress Relief ◽

Heating Time ◽

Post Weld Heat Treatment ◽

Weld Residual Stress ◽

Pressure Vessel Steels ◽

Parametric Analyses ◽

Holding Temperature ◽

Weld Heat

This paper focuses on analysis of weld residual stress relief process during furnace-based uniform post-weld heat treatment (PWHT). Two classes of pressure vessel steels: 2-1/4CrMo and carbon steel are considered in seam weld configurations. It is found that the dominant mechanism for residual stress relief is the creep relaxation that occurs much earlier during a PWHT cycle than typically expected. This phenomenon is further confirmed by experimental data. After a large number of parametric analyses of various PWHT parameters, a simple form of relationship is proposed for relating residuals stress relief to a set of PWHT parameters for the two classes of steels. These parameters include PWHT ramp-up heating time, PWHT holding time, PWHT holding temperature, and weldment thickness.

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Efek Post Weld Heat Treatment terhadap Sifat Mekanik AISI 316 Hasil Pengelasan GTAW

Jurnal Mekanik Terapan ◽

10.32722/jmt.v1i2.3354 ◽

2020 ◽

Vol 1 (2) ◽

pp. 81-87

Author(s):

Ahda Arifah ◽

Sidiq Ruswanto

Keyword(s):

Heat Treatment ◽

Post Weld Heat Treatment ◽

Holding Time ◽

Aisi 316 ◽

Weld Heat

Proses pengelasan dengan GTAW menggunakan eletroda tungsten tak cair dengan diameter 3,2 mm, filler rod NSN - 316LR, dan gas argon 99%. Post Weld Heat Treatment (PWHT) adalah suatu proses untuk menghilangkan tegangan sisa akibat panas yang dihasilkan pada saat pengelasan dengan cara memanaskan kembali material di bawah suhu kritis bawah dan ditahan beberapa waktu kemudian didinginkan dengan pendinginan lambat. Proses PWHT yang memengaruhi sifat mekanik, yaitu suhu, holding time, dan media pendingin. Penelitian ini difokuskan pada pengaruh holding time pada saat proses PWHT terhadap sifat mekanik AISI 316. Tujuan Penelitian ini adalah menganalisis pengaruh parameter holding time pada proses PWHT terhadap kekerasan mikro dan kekuatan tarik AISI 316 hasil pengelasan GTAW. Metode penelitian ini dilakukan dengan variable bebas yaitu holding time selama 1, 2, dan 3 jam. Parameter tetap yang digunakan pada penelitian ini adalah suhu dan pendinginan yang dilakukan dalam furnace tertutup hingga mencapai suhu ruang. Hasil dari uji kekerasan mikro bagian lasan tertinggi 500,5 HV dan terendah 302,1 HV, sedangkan hasil uji kekuatan tarik tertinggi 520 N⁄〖mm〗^2 dan terendah 411,3 N⁄〖mm〗^2 . Parameter holding time pada proses PWHT berpengaruh terhadap kekerasan mikro dan kekuatan tarik material.

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