Inservice inspection of cladding using phased array ultrasonic testing system

Abstract

Cladding is process of coating of low alloy base with high alloy overlay to safeguard the base metal from corrosive fluids and fumes. Conventional ultrasonic testing is used to detect flaws in cladding and to enhance the quality of the product during the manufacturing stage. When the component is put to operation, miniscule flaws could propagate due to high working temperatures and pressures thereby reducing the service life of the product. Process plants and nuclear power plants undergo periodic in-service inspection to verify the integrity of components using NDE technique. Conventional ultrasonic testing is limited in application and Phased array ultrasonic testing (PAUT) as an advanced NDE technique could be a viable alternative. This paper details about the application of PAUT to detect a variety of bonding layer flaws in in-service inspection of cladded components.