厚壁设备筒体焊缝开裂问题及改进措施

大厚壁设备筒体(板材最薄处为34 mm)在施工过程中由于受约束和环境等因素影响,传统工艺方式、方法施工后导致焊缝出现裂纹缺陷;本文通过对大厚壁设备筒体在施工过程中定位焊、打底、焊后热处理的三个阶段焊缝出现裂纹进行描述,针对环境影响因素、施工工艺和施工方法等原因进行分析,制定切实有效的改进措施,通过增加定位焊密度、定位焊厚度、焊后缓冷以及调整分段热处理次数的过程控制等方法来避免焊缝再次出现裂纹缺陷,结果证明所采取的措施切实可行;能够避免设备筒体后续拼装焊接活动中再次出现裂纹缺陷,同时可为后续类似大厚壁设备筒体拼装活动提供有效的经验借鉴,确保与之相关领域大厚壁焊缝组对焊接能保质保量顺利完成。

Cracking of weld seam of thick-wall equipment cylinder and improvement measures

The large thick wall equipment tube(52 mm at the thinnest part of the plate) was affected by constraints and environment during the construction process,and the traditional technology method and Fangfashigong caused cracks in the weld seam. In this paper,we describe the cracks in three stages of welding,bottom beating and post-welding heat treatment during the construction of large thick wall equipment,analyze the environmental factors,construction technology and Shigongfangfa,and formulate effective improvement measures. The method of increasing the density of positioning welding,the thickness of positioning welding,the slow cooling after welding,and adjusting the process control of the number of segmental heat treatment are used to avoid the crack defects again. It can avoid the crack defects in the subsequent welding activities of the equipment cylinder,and it can provide effective experience for the subsequent assembly activities of the similar thick wall equipment,and ensure the smooth completion of the welding energy and quality of the large thick wall weld group in the relevant fields.