Pulsed Eddy Current Testing of Inner Wall Flaws in Pipe under Insulation

Development of Pulsed Eddy Current Testing System for Wall Thinning through Insulation with Ferromagnetic Cladding

Corrosion is one of the important factors in equipment failures. Wall thinning can be used to evaluate corrosion conditions. However, most of equipments are coated with insulations in order to elevate the energy efficiency. Pulsed eddy current (PEC) testing technique can be used to measure wall thinning through insulation. But when the insulation outside is wrapped with galvanized steel, PEC si...

Eddy Current Testing with Giant Magnetoresistance (GMR) Sensors and a Pipe-Encircling Excitation for Evaluation of Corrosion under Insulation

This work investigates an eddy current-based non-destructive testing (NDT) method to characterize corrosion of pipes under thermal insulation, one of the leading failure mechanisms for insulated pipe infrastructure. Artificial defects were machined into the pipe surface to simulate the effect of corrosion wall loss. We show that by using a giant magnetoresistance (GMR) sensor array and a high c...

Pulsed Eddy Current Sensing for Critical Pipe Condition Assessment

Pulsed Eddy Current (PEC) sensing is used for Non-Destructive Evaluation (NDE) of the structural integrity of metallic structures in the aircraft, railway, oil and gas sectors. Urban water utilities also have extensive large ferromagnetic structures in the form of critical pressure pipe systems made of grey cast iron, ductile cast iron and mild steel. The associated material properties render N...

Differential Hall-sensor Pulsed Eddy Current Probe for the Detection of Wall thinning in an Insulated Stainless Steel Pipe

Standard Flaws for Eddy Current Probe

Calibration procedures for eddy current inspections often involve the use of artifact standards containing manufactured flaws. The manufactured flaw is assumed to be a good approximation of the type of flaw being sought during the inspection. These manufactured flaws are most often produced by electrical dis charge machining (EDM) , milling, or the controlled growth of fatigue cracks. With simp...