Based On The Coercivity Of Ferromagnetic Material Stress Detecting Technology

Pipeline as the fifth major transport industry, in the national economic and social development has assumed a very important role. Because the pipeline is mostly buried in the ground, in the wet soil is very easy to corrosion. At present, the main external anticorrosive coating and cathodic protection of two kind of way, although the external anti-corrosion layer can reduce the corrosion of more than 90% of the, but material anti-corrosion layer will with the passage of time and ageing, in the construction of concrete, coated with anticorrosive layer will inevitably because of construction personnel negligence caused by scratches and defects, then cathodic protection system for the anticorrosion layer breakage point provides protection. In addition, some parameters of the buried pipeline can be measured by measuring the cathodic protection to judge the health of the corrosion protection layer, which is an effective method to detect the defects of the buried pipeline.The targeted by collecting pipe / off potential to judge the anticorrosion coating defects of close interval potential detection system are studied in detail, on electrochemical corrosion principle, cathodic protection principle do in-depth study, introduced by measuring cathodic protection of some of the parameters to determine methods for the detection of buried pipeline anticorrosion coating and cathodic protection system health, theory to prove the obvious mutation in anticorrosion coating defects of pipeline potential. To close interval potential detection principle, testing process and testing need to pay attention to the problem were description and explanation, and in view of the close interval potential detection method in the time synchronization problem, the introduction of the Beidou satellite time synchronization method, and prove the accuracy of time synchronization have important influence on the detection accuracy of the whole system. Analysis of the mechanism of the Beidou synchronous second pulse, and the reason for the delay of the synchronization pulse. Based on the above analysis, the hardware structure design of N UM220-III Beidou satellite chip as the core processing chip is given, which is based on STC89C52 RC single chip microcomputer. The system consists of 5 parts, which are potential collector, current interruption device, time synchronization module, reference electrode and mileage wheel.Firstly, the current interrupt device performance in the experiments. The experimental results show that current interruption synchronizer is good, response time to reach 180 us. The response time is 23 us satellite synchronous pulse synchronous reachability 100 ns repeated experiment indicated that the standard differential. Through the simulation experiment platform is built to simulate the cathodic protection of anticorrosive layer defect situation and will application of this system in the simulation platform. The results show that the detection system can qualitatively determine the buried pipeline coating defect and resolvable minimum defect radius 3.7 cm.