The purpose of this research is stability estimation of plant structure through classification and
recognition about welding flaw in SWP(Spiral Welding Pipe). And, In this research, we used
nondestructive test based on ultrasonic test as inspection method, and made up inspection robot in
order to control of ultrasonic probe on the SWP surface, and programmed to signal processing code
and pattern classifying code by user made programming code. Inspection robot is simply
constructed as 2-axes because of welding bead with fixed pitch. So, inspection of welding part can
be possible as composition of inspection part for tracking on welding line. For evaluation of flaw
signal is reflected on welding flaw, user-made program codes are composed of signal processing
and Bayesian classifier and perceptron neural network and back-propagation neural network. And
then, we confirmed to superiority of neural network method compared with Bayesian classifier for
classification and recognition rate. According to this result, we selected back-propagation neural
network as classification and recognition method about the system of SWP stability Estimation[2].
Through this process, we proved efficiency on the system of SWP stability Estimation, and
constructed on the base of the system of SWP stability Estimation for the application in industrial
fields.