Marine Array-type Electromagnetic Detection System Development

Ships, as an important transportation equipment, has played an important role in the development of the national economy. Shipbuilding industry has developed into a national pillar industry. We received the most orders of building the new ships in the world in 2009, the shipping industry is developing from a big country to a strong nation, our economic and trade in the world economic crisis has been stabilized and rapid development, import and export trade 30% rely on transportion of our own merchant fleet.Non-destructive testing is an integral part in the manufacture, maintenance and management of ship's fitting, despite the non-destructive testing technology has been a century of history, but there are still many gaps in the field of research and application of the ship. Contraposing the current situation of domestic and overseas, this thesis discuss the magnetic flux leakage testing and research and development marine magnetic flux leakage inspection system, provide a new way for marine equipment of nondestructive testing.In this paper, based on MFL theory,according to the characteristics of magnetic methods, magnetic intensity and the local magnetization and other requirements, designed the portable body excitation mechanism. By two-dimensional finite element analysis, show that the size of permanent magnet is meet the requirements of magnetic capacity in the certain thickness of the steel. In according with technical parameters of the sensor, designed data collection system in the signal acquisition which use C8051F020 MCU as the core; using Low-noise amplifier circuit and the Second low-pass filter consist the data acquisition module; put in to use 12864 LCD, designing display module that displays the data interface waveform. In order to obtain functions of the detection system, programming the display, acquisition and processing, communications, key and print subroutine by using C language. The main program invoking subprogram and achieve the functions of the MFL signal acquisition and data processing.Comparing experiments, show that the detection system can detect the presence of the defects, it is foundation for marine portable array-type electromagnetic detection system's research and development.