承压设备厚板中频感应加热局部热处理试验研究

Experimental Study on Local Heat Treatment of Thick Plate with Medium Frequency Induction Heating in Pressure Equipment

为了实现承压设备总装环缝局部热处理,基于中频感应加热技术,研究了超厚板在感应加热过程中的温度分布规律及温度均匀性。热处理过程中均温区的温度均匀性是保证局部热处理效果的关键。以马鞍形厚板为研究对象,进行感应加热试验,利用布置在不同深度的热电偶测量感应加热过程中沿壁厚方向的温度演化曲线。同样,将感应加热应用于加氢反应器筒体,测量感应加热过程中沿轴向方向的温度演化曲线。结果表明:马鞍形厚板在整个感应加热过程中沿壁厚方向最大温差在17℃以内,在保温阶段的最大温差为14.4℃;加氢反应器筒体焊接接头均温区在整个感应加热过程中最大温差在42℃以内,在保温阶段的最大温差为12℃。感应加热温度控制精度能够满足超厚板局部热处理均温性的要求,可在大型厚壁容器局部热处理中推广应用。

In order to realize the local heat treatment of the cylinder to cylinder girth welds of pressure equipment,the temperature distribution and temperature uniformity of the ultra-thick plate during the induction heating are studied based on the medium frequency induction heating technology.The temperature uniformity of the soak band during the heat treatment is the key to ensure the effect of the local heat treatment.The induction heating experiments were carried out on the saddle-shaped ultra-thick plate,and the temperature evolution curve along the direction of wall thickness during the induction heating were measured by using thermocouples arranged at different depths.Similarly,the induction heating experiments were applied to the heavy hydroprocessing reactor cylinder,and the temperature evolution curve along the axial direction during the induction heating were measured.The results show that the maximum temperature difference of the saddle-shaped thick plate during the whole induction heating process is within 17℃,and the maximum temperature difference at the preservation stage is 14.4℃.The maximum temperature difference in the uniform temperature zone of the welded joints of the heavy hydroprocessing reactor cylinder during the whole induction heating process is within 42℃,and the maximum temperature difference at the holding stage is 12℃.The precision of induction heating temperature control can meet the requirements of local heat treatment of ultra-thick plates,and can be widely used in local heat treatment of large thick-walled vessels.