A Study on optimization of welding process parameters for J-Groove dissimilar metal weld repair of pressurizer heater sleeve in nuclear power plants

Cho, Hong Seok; Park, Ik Keun; Jung, Kwang Woon

doi:2015.33.1.87

J Weld Join > Volume 33(1); 2015 > Article

Research Paper

Journal of Welding and Joining 2015;33(1):87-93.
DOI: https://doi.org/10.5781/JWJ.2015.33.1.87 Published online February 28, 2015.

A Study on optimization of welding process parameters for J-Groove dissimilar metal weld repair of pressurizer heater sleeve in nuclear power plants

Hong Seok Cho^*, Ik Keun Park^**, Kwang Woon Jung^***

Correspondence: Kwang Woon Jung,
Email: jungkw99@kps.co.kr

Abstract

This study was performed to develop repair technology for J-Groove dissimilar metal weld of pressurizer heater sleeve in nuclear power plants. Pad, J-Groove automatic welding and mechanical machining equipments to develop repair technology using ‘Half Nozzle Repair’ were designed and manufactured. To obtain the optimum welding process parameters during Pad temperbead overlay welding, several welding experiments using Taguchi method were conducted. Weldability of Pad overlay weld specimens was estimated by PT/RT test, FE-SEM, EDS and Vickers hardness test. Also, J-Groove welding to adjust weld shape conditions requiring in ASME Code was carried out and its integrity of weld specimens was evaluated through PT/RT test and optical microscope. Consequently, it was revealed that Pad and J-Groove overlay welding for dissimilar metal weld of pressurizer heater sleeve could be possible to meet Code standard without weld defect.

Key Words: ASME code, Temperbead welding, J-Groove welding, Half nozzle repair, Vickers hardness