Cracking Analysis and Repair of High-Pressure Main Steam Combined Valve Welds in Through-Flow Transformation Units

ZHANG Jinsheng; WANG Qingfeng; LIU Yanru; XU Liang; AN Zhitong; MA Zhibao; CHEN Xin; DU Shuangming

doi:10.7512/j.issn.1001-2303.2024.07.19

Failure analysis and repair | Views : 0 下载量: 7 CSCD: 0

PDF
Export
Share
Collection
Album

Cracking Analysis and Repair of High-Pressure Main Steam Combined Valve Welds in Through-Flow Transformation Units
Vol. 54, Issue 7, Pages: 132-137(2024)
Published： 25 July 2024 ，
DOI： 10.7512/j.issn.1001-2303.2024.07.19
稿件说明：

扫描看全文

张金生，王庆峰，刘彦如，等.通流改造机组高压主汽联合阀焊缝开裂分析及处理建议［J］.电焊机，2024，54（7）：132-137.

ZHANG Jinsheng, WANG Qingfeng, LIU Yanru, et al.Cracking Analysis and Repair of High-Pressure Main Steam Combined Valve Welds in Through-Flow Transformation Units[J].Electric Welding Machine, 2024, 54(7): 132-137.
张金生，王庆峰，刘彦如，等.通流改造机组高压主汽联合阀焊缝开裂分析及处理建议［J］.电焊机，2024，54（7）：132-137. DOI： 10.7512/j.issn.1001-2303.2024.07.19.

ZHANG Jinsheng, WANG Qingfeng, LIU Yanru, et al.Cracking Analysis and Repair of High-Pressure Main Steam Combined Valve Welds in Through-Flow Transformation Units[J].Electric Welding Machine, 2024, 54(7): 132-137. DOI： 10.7512/j.issn.1001-2303.2024.07.19.

摘要

针对某机组通流改造后高压主汽阀和高压调节阀的R337对接焊缝出现的横向裂纹问题进行深入分析。通过观察现场裂纹、分析样品以及评估材料性能，确定裂纹形成的主要原因。首先，焊材R337的选用不当导致了焊缝脆性的增加，其次，结构应力和交变应力的叠加作用加速了裂纹的扩展；ZG15Cr1Mo1V钢的碳当量较高，具有较大的淬硬倾向，容易产生冷裂纹，而Nb元素的加入则增加了再热裂纹的敏感性。针对裂纹形成的原因提出了处理建议，首先彻底清除原有的R337焊缝，并采用低匹配的R317焊条进行修复；在焊接过程中，严格控制预热温度、层间温度和焊接线能量，以减少焊接应力；焊后进行中频感应热处理，以均匀温度场并充分消减应力；考虑到ZG15Cr1Mo1V钢的再热裂纹倾向，建议在修复过程中采取适当的预防措施。

Abstract

This paper conducts an in-depth analysis of the transverse crack issues in the R337 butt weld of the high-pressure main steam valve and high-pressure regulating valve after the through-flow transformation of a certain unit. By observing on-site cracks

analyzing samples

and evaluating material performance

the main causes of crack formation were determined. Firstly

the improper selection of the R337 welding material led to an increase in the brittleness of the weld. Secondly

the superimposed effects of structural stress and alternating stress accelerated the expansion of the cracks; the high carbon equivalent of ZG15Cr1Mo1V steel makes it prone to cold cracking

and the addition of Nb elements increases the sensitivity to reheat cracking. Based on the causes of crack formation

treatment suggestions were put forward

which include the thorough removal of the original R337 weld and the repair with a lower-matched R317 welding rod; during the welding process

strict control of preheating temperature

interlayer temperature

and welding line energy is required to reduce welding stress; post-weld heat treatment by induction heating is carried out to evenly distribute the temperature field and fully relieve stress; considering the reheat cracking tendency of ZG15Cr1Mo1V steel

appropriate preventive measures are recommended during the repair process. This study not only provides technical basis for the repair of high-pressure main steam valve welds but also offers references for similar material and structural welding repair work.

关键词

ZG15Cr1Mo1V横向裂纹失效分析焊接修复

Keywords

ZG15Cr1Mo1Vtransverse crackingfailure analysiswelding repair

references

赵彦芬，张路，张欣原，等.高温主汽用15X1M1Φ钢接头失效及解决措施［J］.中国电力，2010，43（08）：1-6.

ZHAO Y F，ZHANG L，ZHANG X Y，et al. Failure and Solutions of 15X1M1Φ Steel Joints for High Temperature Main Steam［J］. China Electric Power，2010，43（08）：1-6.

SHI W，LV Y S，CHEN Z B，et al. Cause Analysis and Preventive Measures against Cracks in 15Cr1Mo1V Steel Welded Joint in Service［J］. Applied Mechanics and Materials，2017，863：328-333.

杨太勇，梁红兵，马为民，等. ZG15Cr1Mo1V钢热补焊接头组织与力学性能研究［J］. 热加工工艺，2018，47（19）：226-229.

YANG T Y，LIANG H B，MA W M，et al. Study on Microstructure and Mechanical Properties of ZG15Cr1Mo1V Steel Hot Repair Welded Joints［J］. Hot Working Technology，2018，47（19）：226-229.

安志彤，魏广海，赵卫东，等. ZG15Cr1Mo1V阀门镍基焊条冷补修复［J］. 华北电力技术，2006（12）：28-29.

AN Z T，WEI G H，ZHAO W D，et al. Cold Repair of ZG15Cr1Mo1V Valve with Nickel-Based Welding Rod［J］. North China Electric Power Technology，2006（12）：28-29.

张东文，王庆，姜运健，等. 汽轮机自动主汽门裂纹的分段冷焊修复［J］. 焊接，2002（11）：44-45.

ZHANG D W，WANG Q，JIANG Y J，et al. Segmented Cold Welding Repair of Cracks in Turbine Main Steam Automatic Valve［J］. Welding，2002（11）：44-45.

Jha A K，Manwatkar S K，Narayanan P R，et al. Failure analysis of a high strength low alloy 0.15C-1.25Cr-1Mo-0.25V steel pressure vessel［J］. Case Studies in Engineering Failure Analysis，2013，1（4）：265-272.

肖章玉，曾国成，宁德林，等. 一次正火与两次正火对ZG15Cr1Mo1V材料性能和组织的影响［J］. 大型铸锻件，2017，177（03）：27-29.

XIAO Z Y，ZENG G C，NING D L，et al. The Effect of Single Normalizing and Double Normalizing on the Properties and Microstructure of ZG15Cr1Mo1V Material［J］. Large Castings and Forgings，2017，177（03）： 27-29.

周振丰. 焊接冶金学（金属焊接性）［M］. 北京：机械工业出版社，1993.

章守华. 合金钢［M］. 北京：冶金工业出版社，1981.

马志宝，李凤强，陈鑫，等. ZG15Cr1Mo1V铸件热补焊技术［J］. 焊接，2021（07）：53-56+64.

MA Z B，LI F Q，CHEN X，et al. Hot Repair Welding Technology for ZG15Cr1Mo1V Castings［J］. Welding，2021（07）：53-56+64.

Alert me when the article has been cited

提交

Failure Analysis of Three-eccentric Center Butterfly Valve and Its Plasma Cladding Repair with Stellite alloy

Failure Analysis of T91+TP347H Dissimilar Steel Welded Joints

Failure Analysis of 350MW Sub-critical Boiler Low Temperature Reheater

Failure Analysis of Valve Stems and Their Laser Cladding Repair

Analysis of Cracking Causes in Welding Structures of High Strength Steel for Offshore Ultra Thick Plate