Automatic On-line Thickness Testing Method And System For Pipes

Wall thickness must be measured as the API improved the testing standards for pipe quality that the wall thickness changes must be guaranteed in the range of permit. So it is very urgent that automatic on-line thickness testing system for pipe should be developed as soon as possible.According to both the requirement of automatic testing system at high speed and the mode pipes moving, analyzing the local wall thickness loss, taking into account the manufacturing capacity and cost, three methods, namely the magnetic flux leakage magnetic ,main magnetic flux and a bridge-based method is researched to measure the wall thickness of pipes. After comparisons of the characteristics of each method, the bridge-based method is researched as a emphases. Basing on these methods and some experiments, three wall thickness measurements equipment system were designed, and their capability had been tested. The full pipe wall thickness measurement system is designed based on these researches. the on the spot debugging and the factors which affect the testing precision were analyzed, this validate practicability of the system. Up to now, these systems had been proved to be fast and credible. on the other hand, the system cost far less than the import system.Also the ultrasonic water immersion thickness testing method is researched in this pape. A water immersion structure testing boot was designed basing on the analyzing the factors which affect the testing precision. and the experiment showed that this structure is fit for on-line testing. What's more a testing signal collecting and processing system was designed for the automatic on-line thickness testing.