The Search Of Acoustics Testing Method For Pressurized Valves Leakage

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.