彭以超,楼玉民,叶笃毅,许好好
PENG Yichao,LOU Yumin,YE Duyi,XU Haohao

• 1:浙江浙能技术研究院有限公司材料技术所
• 2:浙江省火力发电高效节能与污染物控制技术研究重点实验室
• 3:浙江大学化工机械研究所

摘要(Abstract)：

以上汽超超临界机组中压汽门(包括中主门和中调门)阀盖螺栓系统为研究对象,开展了典型工况(包括预紧、启动、稳定工况)下螺栓整体与局部螺纹牙部位的三维有限元应力分析,以探索研究Alloy783螺栓服役过程中经受的应力对于螺栓断裂的影响。结果发现:预紧力过大是造成Alloy783螺栓大批量断裂的一个较大促进因素,中压汽门阀盖螺栓在3种典型工况下的有限元应力计算最大应力均集中在螺纹部分与螺母或阀体咬合的第1颗螺牙位置,启动工况时螺栓内应力最大。降低预紧力伸长量后,中压汽门螺栓预紧力相对于以往也发生了明显的降低,使得螺栓短期断裂的比例显著下降。
In this paper, the steam valve cap bolts(including medium-pressure main and regulating valve) of the ultra-supercritical units are taken as the research objects. Three-dimensional finite element stress analysis on bolt body and screw thread under the typical conditions(including prefastening, startup and stable operating condition) is completed to investigate the stress of bolt Alloy 783 on its breakage when in service. It is found that excessive prefastening is a major contributor to the massive fracture of the bolts. The maximum stress calculated by the finite element stress in the three typical operating conditions is at the first thread of the intersections between the thread and nut or valve body, and the internal stress rises to the maximum during the startup. With the prefastening elongation reduced, the preload of medium-pressure valve bolt is also reduced significantly compared with the past, and the proportion of short-term bolt fracture is greatly reduced.

关键词(KeyWords)： 超超临界机组;Alloy783;螺栓;断裂;有限元应力分析
ultra-supercritical unit;Alloy783;bolts;fracture;finite element stress analysis

Abstract:

Keywords:

基金项目(Foundation):

作者(Author): 彭以超,楼玉民,叶笃毅,许好好
PENG Yichao,LOU Yumin,YE Duyi,XU Haohao

DOI: 10.19585/j.zjdl.201804015

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