The Research Of Real Time Testing Of Steel Pipe Crackle

The paper introduces the technology applies and theory research conditions of eddy-curent sensor, reveals the large spatial difference between our country and others about in real detection of steel pipe crackle. Though the analysis of statical and dynamic characters on eddy-current sensor, it puts forward the influence factors of detective range and sensitivity and linear. On the other hand, it also makes dynamic character factor equel to two inertia system .It not only improves dynamic character but also has little influences to sensitivity by correcting with non-power circuit.Through massive experiments, we can get that it is feasible to detect little flaw by big sensor, and it is also verified that the method which discerns the crackle by coil impedance phase has better linear, higher sensitivity, wider detective range and better anti-interference than by amplitude, it is ordinary and effective to solve problem of seting up sensor by testing two parameter with one work frequency on the basis of using two least multiplication.The system uses TMSC548 of TI co. as the whole detective CPU. The excited power circuit adopts MAX038 as a core according to capability and value. On the basis of detecting the phase difference by correlative method with CCS software, the paper puts forward a method that detects the phase difference by taking count of equivalent pulse width, and preset counter's value so that DSP need not deal with the signal when there has not crackle. It can largely reduce the DSP possess rate of time and space. The synchronism signal is obtained by laser equipment.At last, the paper has put forward some effective means of software and hardware anti-interference about built-in system.