Study On Material Classification About Inside And Outside Of In-serve Pipeline's Images Detected By X-ray

The pipeline is one of the present five big major carriers. As the pipeline service time gets longer and the pipeline gets older, pipeline security issues running more and more people's attention. The scientific and technical workers continuously have been seeking a better detection methods if it is possible to complete pipeline's inside and outside material separation, and obtain the pipe wall thickness under the normal operation of state, without demolishing the thermal insulation layer. This method can not only resume the economic loss which is caused by the production suspension demolition and the thermal insulation layer creation, reduces the invalid redundant work and the production costs, but also May evaluate the pipeline in the service pipeline's remaining life Scientifically, then guarantee the pipeline safe reliability service.The purpose of this article is to use the inspection method which need not remove the thermal insulation layer to carry material one by one to the pipeline, the internal medium, the exterior packing (thermal insulation, anticorrosion level) on the classified rejection, aiming at testing the pipeline remaining thickness. It is advantageous for pipeline's pipeline the failure analysis, pipeline residual strength appraisal, remaining life predict, fail-safe analysis and risk management and pipeline's serviceable appraisals and so on quality condition. This paper mainly deals with the following parts:First of all, it is to understand components of the service pipeline X-ray detection system components, to analysis system performance and evaluation indicators including resolution, dynamic range and so on, then to carry on the structure dissection in the service pipeline, to understand material composition and the constitutive property of its pipeline material and the heat insulating layer.Secondly, Classify the materials into organic,inorganic and mixture by effective atomic number. After some algorithm, find two boundary materials for object classification. Draw tests'scenario, collecting data and modeling the curve. The key technologies that need to solve is how to carry on the classified rejection which is from the inside and outside of pipeline. Establishing the correct mathematical model through the experiment to solve the X-ray passing through the pipeline image formation in different thickness, then definiting pipeline wall thickness from the changes of image gradation level and mathematical model, so that achieving security checking goal in the service pipeline.