Development and performance evaluation of a magnetic climbing NDT system for the inspection of ferritic structures

This paper presents the design and performance results of a magnetic climbing NDT system on a steel tank wall. The magnetic climbing system comprises a compact, remotely operated, magnetically attached crawler for detecting flaws and measuring the remaining wall thickness of tanks, spheres, pressure vessels, and large diameter piping. The vehicle has encoders to measure the distance climbed. The vehicle also carries an ultrasonic dry contact wheel probe. The climbing system provides a fully integrated, PC based ultrasonic flaw detector. An ultrasonic location finding system is also developed to find the global coordinates of the wheel probe on the vehicle to obtain large C-Scans (2m x 2m).