振动时效工艺在消除膨胀波纹管残余应力中的应用

Application of vibratory stress relief in relaxation of residual stress for expandable corrugated liners

膨胀波纹管体冷压成型后存在较大的残余应力常导致管端面严重变形和尺寸不稳定,已成为制约管体焊接连接质量和效率提高技术瓶颈。探索振动时效法用于消除或减弱波纹管体残余应力的可行性。结合室内试验和现场试验数据,建立振动时效法适用的关键技术、工艺参数、评价方法以及后处理分析手段。采用所建立的评价体系,通过振动时效参数曲线观测和盲孔法残余应力测量,评定了该试验振动过程及振动时效效果有效性,这证明振动时效工艺可显著降低膨胀波纹管残余应力,能够满足膨胀波纹管焊接等工程需要,提高其尺寸稳定性。

The bigger residual stress can be left in expandable corrugated liners after their cold press molding. This leads to both the serious deformation and the unstable sizes at the liner ends. This defect becomes the techinical bottleneck to restrict welding quality and efficiency of liners connection. Here, a feasible method was proposed to remove the residual stress in the liner as much as possible. A set of crucial techniques, parameters, assessing methods, and post-processing methods based on plenty of data obtained from tests and sites was developed for the vibratory stress belief method. The new assessing system was used to verify the effectiveness of the vibratory stress belief effects through monitoring the parameter curves of the vibratory stress belief and residual stress measured with the blind-hole method. The results showed that the proposed method can be applied to decrease residual stress greatly in liners, it can meet the requirements of corrugated liners welding.