Currently, pipeline corrosion testing has the following difficulties:
√ Near field issues of ultrasound probes shall be considered.
√ Rough pipe surface may lead to poor coupling of probes.
√ A crawler adapted to section changes and structural changes is required.
√ Accurate measurement and evaluation of corrosion depth is required.
√ Testing for high-risk parts with liquid flow changes that may lead to corrosion in elbows, flanges, tees and variable diameters shall be applicable.
Ultrasonic phased array is an ultrasonic imaging technology that performs area inspection on pipeline corrosion. It is combined with a corrosion mapping scanner with light weight and simple structure to form an ultrasonic immersion testing system suitable for field conditions. The system has the characteristics of small blind zone, high precision, 100% coverage without missed detection, intuitive test results, traceability and high efficiency. Comparing to leakage flux and guided wave methods, it has advantages of less false signals and improved accuracy in corrosion testing of cross-section structural parts such as elbows, tees and variable diameters.