The Design Of Oil Pipeline Leak Detection System

As one of the most important five means to transportation,pipeline transportation has become the artery of national economy modern enterprise.With the development of pipeline industry,pipelines aging,inevitable erosion,abrasion and human destroying,pipelines leakage occurs frequently,which not only affects the normal production,but also lead to serious pollution to the environment.Therefore,leak detection has become a significant part of pipeline malfunctions detection.The research status of pipeline leakage detection technology home and abroad is summarized in this thesis.Study on the leak detection and location technology.Design a acoustic leak detection system which should systematic to leak hunting acoustic wave law,negative pressure wave method and flow balanced law combine together,leak hunting law as the main fact with the negative pressure,the balanced method of flow and shoulder the acoustic in order to complement.This thesis described the causes of pipeline leaks,and the difference of variety detection methods.Sound wave methods focus on the prevention.Mainly in the formation of leakage is not carried out to alarm;negative pressure wave method and flow balance method is mainly carried out to determine the leak detection.When the leak generated, there will be a spread of negative pressure wave along the pipeline.Thesis analyzes the negative pressure wave propagation laws, method of calculating wave velocity and temperature on the impact velocity.And use of wavelet analysis theory, deal with the signal de-noising and get the arrival time difference of signals.Use formula to estimate the location of leakage points.In software design using the Delphi language so that the development process is unified and simple.Principle, system construction, signal acquisition, signal processing and data processing aspects are discussed and analyzed in this thesis.According to pipeline leakage monitoring require.System hardware selection has been completed.Pipelines are exposed outdoors for years,the natural conditions is uncertainty.Therefore ,to choose quality reliable sensors is necessary.The sensor selected in the thesis,are highly precision and reliable,which consistent with site requirements,able to guarantee the collection of monitoring signal quality.Because of pipelines layout dispersion,use of wire-line communication is difficult.The distance of the radio transmission achieved is more far than the wire-line.Therefore use of RTU and radio combination for long-distance signal transmission;If signal is to be analyzed accurately,the signal acquisition must be synchronized in time on arrival.GPS satellites can provide high-precision Standard Time and not subject to geographical constraints.Setting the GPS receiver for signal acquisition synchronous is to be needed.And structured at the scene at the experimental platform,a leak simulation had experimented and had analyzed the experimental results.