【作者】 王新颖；

【导师】 戴光；

【作者基本信息】 大庆石油学院 ， 安全技术及工程， 2004， 硕士

【摘要】 阀门是流体管路的控制装置，其基本功能是接通或切断管路介质的流通，改变介质的流动方向，调节介质的压力和流量，保护管路和设备的正常运行。阀门作为一种通用的机械产品，在国民经济的各个领域被广泛应用，它的安全性一直是人们关注的焦点。由于阀门泄漏造成的经济和社会损失是十分惊人，而针对阀门内漏的检测手段较少且效果较差。声发射检测技术作为一种新兴的动态无损检测技术，具有在线、动态及快速、经济的特点，既保证了阀门的安全使用，又可为维修决策提供依据，降低了更换费用。因此，开展承压阀门内漏声学测方法研究具有重要意义。 通过对承压阀门内漏过程分析表明，在阀门湍流流场中，因为有泄漏缝隙的存在，必将产生四极子声。在固体边界效应大的情况下，对于复杂结构的阀门，也将产生偶极子声。研究不同类型阀门内漏声源特征参量与阀门泄漏率的关系，建立阀门泄漏率定量评价的数学模型。上述研究对后续的模拟阀门内漏实验具有重要的指导作用，而且对现场阀门的声发射检测与分析提供了重要的理论依据与指导。 建立模拟在用承压阀门内漏实验台，研究典型阀门内漏声源的声学特性，确定声发射特征参量与泄漏率的关系，为定量评价阀门泄漏率提供实验数据；通过对不同类型、不同规格、不同工作介质下的典型承压阀门内漏的实验研究，确定阀门内漏最佳检测区域，建立在用承压阀门内漏声学检测方法。根据本次研究工作的目的和特点并结合现场的实际情况，探讨了内漏时阀门开度、阀门类型、两侧压差以及泄漏率等因素变化时的声学特性。并绘制了声发射特征值与泄漏率的相关性曲线，为声发射定量评价泄漏率提供重要依据。 根据目前石油、石化企业阀门使用、维护、检测和更换的现状，结合阀门泄漏声学检测仪器，开发在用承压阀门使用、维护、检测和更换数据库软件。该软件不仅能够实现石油、石化企业阀门使用、维护和更换的科学化和规范化，而且通过对阀门内漏声学检测数据的分析，实现对阀门泄漏率的定量评价。更多还原

【Abstract】 Valves are control equipment in fluid pipelines. Through adjusting valves, medium in the pipeline may get through or be cut off in pipeline. Also, the flowing way, pressure and flux of medium can be controlled to protect pipeline and facility. Valves are required in a wide range of industrial fields as a general product. Therefore, its safety is concerned all along. Valves leakage result in economy and society loss surprising. The method for detecting valves inner leakage is less and un-effectively. According to its on-line, dynamic, rapid and economic characteristic, acoustics testing is a new dynamic nondestructive test method which can ensure valves safety, provide evidence for maintain project, debase to replace expenditure. It is important that acoustic test is applied to valve leakage testing and evaluation.Quadrupole sources come from leaking gap. Dipole sources occur in complex structure valves through analyzing leak in valves. The mathematics model is based on the relation of sources characteristic parameters and leakage rate in order to estimate leakage rate. The study instructs simulating valve leakage experiment, perfects valves leakage test technology and bases theoretically for applying valve leakage test in practice.The test stand is constructed and instrumented to accept a variety of valves in order to determine which characteristics of acoustic emission change with leakage rate. The data for each valve type is generated by varying valve type and working medium. Best test regions are confirmed to found the acoustic emission test method for valve leakage. The large amount of data collected also allowed a brief investigation of the effects of different opening, valve types, differential pressure and leakage rates. The result plots of leakage rate versus acoustic amplitude are the primary basis to determine the feasibility for quantifying leakage rate.According to the current employed condition of valves in industry. The database is developed in order to be convenient for using, maintenance and testing valves. It makes the application, maintenance and replacing of valves scientific and the valves management more normally. Moreover, it could estimate valve leakage rate on basis of the analysis of testing data.更多还原