高水头电站压力钢管安全评定

发布时间：2018-05-15 08:31

本文选题：有限元分析 + 超声检测　；参考：《西南交通大学》2011年硕士论文

【摘要】：压力钢管是水电工程中输水建筑物的重要组成部分,它承受着较大的内水压力以及自身的重量和水重,压力钢管对整个电站的安全运行有着重要的影响。某高水头电站3#斜井段压力钢管在水压试验过程中1#机组右侧配水环管的铸钢闷头突然破裂,3#斜井上平段焊在管节端部的平面闷头便被气浪冲开蹦落在地。此类事故在压力管道的制作与安装过程中从未发生过。为了检查此次事故对压力钢管可能造成的损伤,特别是靠近平面闷头部位管节材料和焊接接头可能产生裂纹以及出现材料应变时效脆化问题,于是本文在管节有限元分析、材料力学性能试验以及CTOD试验的基础上,以GB/T19624-2004标准《在用含缺陷压力容器安全评定》为依据,运用自主研发的水电站压力钢管安全评定系统对某高水头电站水压试验事故后的管节进行安全评定。评定结果表明：1号和5号缺陷为容许存在缺陷,不必进行返修处理：2,3,4号缺陷须进行返修处理。鉴于以上评定结果,对该管节进行返修,返修后再次超声检测表明：3#斜井段靠近闷头处的管节焊缝(环缝和纵缝)探伤全部合格,这为水压试验的再次进行以及该高水头电站的安全运行提供了科学依据。
[Abstract]:Pressure steel pipe is an important part of water conveyance structure in hydropower project. It bears large internal water pressure and its own weight and water weight. The pressure pipe has an important influence on the safe operation of the whole power station. During the hydraulic pressure test of the pressure pipe in the slope section of a high water head power station in the process of water pressure test, the cast steel head of the right water distribution ring pipe of the 1# unit suddenly ruptures and the flat section of the slope well is welded at the end of the pipe and the plane stuffy end of the slope well is flattened by the air wave and bounces to the ground. Such accidents have never occurred in the manufacture and installation of pressure pipes. In order to examine the possible damage caused by the accident to the penstock, especially the crack in the joint material and welded joint near the plane stud, and the problem of strain aging embrittlement of the material, the finite element analysis of the pipe segment is made in this paper. Based on the tests of mechanical properties of materials and CTOD tests, the safety assessment of pressure vessels with defects is the basis of GB/T19624-2004 standard. The safety assessment system for penstock safety of a high head hydropower station was developed. The results show that defects No. 1 and No. 5 are allowed to exist, no rework treatment is necessary, and No. 4 defect must be repaired. In view of the above evaluation results, the repair of the pipe joint has been carried out, and the re-ultrasonic examination after the repair has shown that the weld (girth and longitudinal seam) of the pipe joint near the sulkhead in the section of the inclined well of the 1: 3# slope is all qualified, This provides a scientific basis for the reoperation of the hydraulic test and the safe operation of the high head hydropower station.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2011
【分类号】：TH49

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