Failure Analysis on Weld Leakage of Boiler Water Wall in Thermal Power Plant

XIAO Linfei; YANG Zhanjun; ZHENG Zhunbei; ZHANG Jianwei; ZHOU Ning; HE Hua; TAN Yongsheng; CHEN Jing; WU Yuxing

doi:10.7512/j.issn.1001-2303.2024.04.12

Failure analysis and repair | Views : 0 下载量: 11 CSCD: 0

PDF
Export
Share
Collection
Album

Failure Analysis on Weld Leakage of Boiler Water Wall in Thermal Power Plant
Vol. 54, Issue 4, Pages: 84-90(2024)
Received：12 January 2023，

Revised：2024-03-16，

Published：25 April 2024
DOI： 10.7512/j.issn.1001-2303.2024.04.12
稿件说明：

移动端阅览

校林飞，杨占君，郑准备，等.火电厂锅炉水冷壁焊缝泄漏失效分析［J］.电焊机，2024，54（4）：84-90. DOI： 10.7512/j.issn.1001-2303.2024.04.12.

XIAO Linfei, YANG Zhanjun, ZHENG Zhunbei, et al.Failure Analysis on Weld Leakage of Boiler Water Wall in Thermal Power Plant[J].Electric Welding Machine, 2024, 54(4): 84-90. DOI： 10.7512/j.issn.1001-2303.2024.04.12.

摘要

某12Cr1MoV水冷壁对接焊缝中部出现周向裂纹导致泄漏失效，为调查泄漏失效原因，对焊缝进行了宏观检查、磁粉检测、硬度检验、金相分析、全元素分析和能谱分析，并建立模型分四个阶段讨论了水冷壁焊缝泄漏失效的原因。研究表明：焊缝中夹杂的S元素是焊缝泄漏失效的主要因素，收缩拉应力为偏析在晶界的低熔点共晶物提供了形成沿晶热裂纹的条件，氧气的介入造成热裂纹的局部氧化，实际运行的综合应力使氧化的沿晶热裂纹多点扩展、融合，形成宏观裂纹，最终导致焊缝泄漏失效。

Abstract

A circumferential crack appeared in the middle of a 12Cr1MoV water wall butt weld

leading to leakage failure. In order to investigate the cause of leakage failure

macro inspection

magnetic particle testing

hardness testing

metallographic analysis

full element analysis and energy spectrum analysis were carried out on the weld

and a model was established to discuss the causes of water wall weld leakage failure in four stages. The research shows that the inclusion of S element in the weld is the main control factor of the weld leakage failure. The contraction tensile stress provides the conditions for the formation of intergranular hot cracks for the low melting point eutectic that segregates at the grain boundary. The intervention of oxygen causes local oxidation of the hot cracks. The actual operation comprehensive stress makes the oxidized intergranular hot cracks expand and fuse at multiple points

forming macro cracks

and finally leading to weld leakage

It provides a theoretical reference for leakage failure caused by intergranular thermal cracks in water wall welds of thermal power plants.

关键词

Keywords

references

Dhua S K . Metallurgical investigation of failed boiler water-wall tubes received from a thermal power station ［J］. Engineering Failure Analysis ， 2010 ， 7 （ 17 ）： 1572 - 1579 .

Soudabeh A N ， Price J W H . A risk approach to the management of boiler tube thinning ［J］. Nuclear Engineering and Design ， 2006 ， 236 ： 406 - 414 .

Daneshvar-Fatah F ， Mostafaei A ， Hosseinzadeh T R ， et al . Caustic corrosion in a boiler waterside tube： Root cause and mechanism ［J］. Engineering Failure Analysis ， 2013 ， 28 ： 69 - 77 .

Ameri M ， Shamshirgaran S R . A case study：The effects of the design factors on the thermal profile of Shahid Rajaiee boiler ［J］. Applied Thermal Engineering ， 2008 ， 28 （ 8-9 ）： 955 - 961 .

Rahman M M ， Purbolaksono J ， Ahmad J . Root cause failure analysis of a division wall superheater tube of a coal-fired power station ［J］. Engineering Failure Analysis ， 2010 ， 17 （ 6 ）： 1490 - 1494 .

张冰清，田进，张志博，等 . 火电厂锅炉水冷壁管失效原因分析［J］. 热力发电， 2019 ， 48 （ 5 ）： 97 - 101 .

ZHANG B Q ， TIAN J ， ZHANG Z B ， et al . Failure analysis for boiler water wall tubes in thermal power plants ［J］. Thermal Power Generation ， 2019 ， 48 （ 5 ）： 97 - 101 .

Chaudhuri S . Some aspects of metallurgical assessment of boiler tubes—Basic principles and case studies ［J］. Materials Science and Engineering： A ， 2006 ， 432 （ 1-2 ）： 90 - 99 .

Singh P M ， Mahmood J . Stress assisted corrosion of waterwall tubes in recovery boiler tubes： failure analysis ［J］. Journal of Failure Analysis and Prevention ， 2007 ， 7 （ 5 ）： 361 - 370 .

张兆林 . SA-213TP347HFG膜式水冷壁角焊缝热裂纹原因分析［J］. 电焊机， 2021 ， 51 （ 12 ）： 50 - 55 .

ZHANG Z L . Analysis of hot cr ack in fillet weld of SA-213TP347HFG membrane water wall ［J］. Electric Welding Machine ， 2021 ， 51 （ 12 ）： 50 - 55 .

Xue S ， Guo R ， Hu F ， et al . Analysis of the causes of leakages and preventive strategies of boiler water-wall tubes in a thermal power plant ［J］. Engineering Failure Analysis ， 2020 ， 110 ： 104381 .

董志红，蒙殿武，沈全宏，等 . 锅炉水冷壁横向裂纹开裂原因分析［J］. 电焊机， 2020 ， 50 （ 5 ）： 57 - 61 .

DONG Z H ， MENG D W ， SHEN Q H ， et al . Analysis of transverse crack and high temperature corrosion of boiler water cooled wall ［J］. Electric Welding Machine ， 2020 ， 50 （ 5 ）： 57 - 61 .

Kim E S . Fracture analysis of tube boiler for physical explosion accident ［J］. Forensic science international ， 2017 ， 278 ： 1 - 7 .

Duarte C A ， Espejo E ， Martinez J C . Failure analysis of the wall tubes of a water-tube boiler ［J］. Engineering Failure Analysis ， 2017 ， 79 ： 704 - 713 .

张文钺 . 焊接冶金学［M］. 北京：机械工业出版社， 2005 .

李亚江，王娟 . 焊接缺陷分析与对策［M］. 北京：化学工业出版社， 2014 .

王香云 . 12Cr1MoVG 钢焊接接头热裂纹原因分析及对策［J］. 焊管， 2010 ， 33 （ 4 ）： 13 - 17 .

WANG X Y . Hot Cracking Reason Analysis and Counter measures for 12Cr1MoVG Steel welding Joint ［J］. Welded Pipe and Tube ， 2010 ， 33 （ 4 ）： 13 - 17 .

肖东平，华金良，高淼淼，等 . 某12Cr1MoVG水冷壁管对接焊缝热裂纹成因分析及预防［J］. 电焊机， 2019 ， 49 （ 10 ）： 92 - 96 .

XIAO D P ， HUA J L ， GAO M M ， et al . Reason analysis and prevention measures on hot crack in butt weld of 12Cr1MoVG water wall tubes ［J］. Electric Welding Machine ， 2019 ， 49 （ 10 ）： 92 - 96 .

编辑部网址： http：//www.71dhj.com http://www.71dhj.com