Abstract:
The hydrocarbon industry constantly requires a better understanding of stainless-steel welding metallurgy. Despite the fact that gas metal arc welding (GMAW) is one of the most commonly employed welding processes in the petrochemical industry, the process is characterized by the presence of a high number of variables to control in order to obtain components that are dimensionally repeatable and satisfy the functional requirements. In particular, corrosion is still a phenomenon that highly affects the performance of the exposed materials, and special attention must be paid when welding is applied. In this study, the real operating conditions of petrochemical industry were reproduced through an accelerated test in a corrosion reactor at 70 °C for 600 h, exposing robotic GMAW samples free of defects with suitable geometry. The results show that, even if duplex stainless steels are characterized for being more corrosion resistant than other stainless steels, under these conditions it was possible to identify microstructural damage. In detail was found that the corrosion properties were strongly related to the heat input during welding and that the best corrosion properties can be obtained with the higher heat input.
摘要:
碳氢化合物行业不断需要更好地了解不锈钢焊接冶金。尽管气体保护金属电弧焊(GMAW)是石化行业中最常用的焊接工艺之一,该方法的特征在于存在大量的变量来控制,以便获得尺寸可重复并满足功能要求的部件。特别是,腐蚀仍然是一种高度影响暴露材料性能的现象,焊接时必须特别注意。在这项研究中,通过在70°C腐蚀反应器中进行600h的加速试验,再现了石化工业的实际运行条件,暴露机器人GMAW样品没有缺陷与合适的几何形状。结果表明,即使双相不锈钢的特点是比其他不锈钢更耐腐蚀,在这些条件下,有可能识别微观结构损伤。详细地发现,腐蚀性能与焊接过程中的热输入密切相关,并且使用较高的热输入可以获得最佳的腐蚀性能。