水煤浆工艺烧嘴钴镍异种材料焊接性能研究

Study of Different Material Welding Performance for UMCo50/Alloy600 Used in Coal-water Slurry Gasifier

为了解决水煤浆工艺烧嘴冷却水盘管(镍基材料Alloy600)与外喷头(钴基材料UMCo50)连接焊缝区域的开裂泄漏问题,针对设备的具体应用环境,通过正交试验设计研究了钴镍异种材料焊接,以成型情况、高温拉伸性能、硬度为试验指标,以极差法为分析手段,确定了焊接参数的影响程度及最优焊接参数,同时,在最优焊接参数下对焊缝开展高温腐蚀性和高温氧化性研究,并根据实际运行环境选定了最佳耐蚀焊材。结果显示:焊丝类型和焊接速度是影响焊缝高温抗拉强度的主要因素,焊接最优工艺参数为焊接电流160 A、焊接速度10 cm/min、层间温度不高于150℃、焊接层数2层,填充材料优选ERNiCr-3。最优焊接工艺在实践中推广应用效果明显,经统计计算,焊缝焊接合格率提升了47%。

In order to solve the problem of cracking and leakageoccurred in the welding between cooling water coil pipe(Alloy600)and nozzle(UMCo50)in coal-water slurry gasifier,orthogonal experiment investigationfor UMCo50/Alloy600 weld was carried out to study the effects of various process parameters on the appearance,tensile performances and hardness of the weld.Then weld parameters were optimized by using range analysis method,and the best anti-corruption welding material was found from high temperature corrosion and oxidation tests.The results showed that welding material and welding speed were the most important factorseffecting weld tensile strength;the optimal welding technological parameters should bewelding current 160 A,welding speed 10 cm/min,welding temperature less than 150℃,welding layers2,and welding materialERNiCr-3.There are remarkable effects of optimal welding process used in engineering practice,and the welding qualified rate for the coal-water slurry gasifier had been risen up by 47%.