Encircling ET Inspection on Corrugated Tubes Destined to Gas Tubes for EGR Heat Exchanger

摘要

Subsidiary of Vallourec Group, Valtimet is the world leader for specialized welded tubing products, both straight and special formed tubes. On titanium, stainless steel, super stainless steel, as well as copper alloy, they are dedicated to markets of condenser, feedwater heater and MSR (Modular Stellarator Reactor) applications of highly sophisticated power generations. Valtimet is also the leader for tubing products of desalination, chemical processing, petrochemical and automotive industries.Located in France, China, the United States, India, and South Korea, Valtimet always keeps the most demanding quality control on its premium products.This article describes the solution developed by Valtimet, together with CEV (the Research Centre of Vallourec), for the Eddy-Current (ET) inspection of corrugated tubes, which are destined to automotive industries as gas tubes for EGR (Exhaust Gas Recirculation) heat exchangers. The special corrugated form of these welded tubes generates noises stronger than the signals of reference notches, making the inspection impossible nowadays by existing systems.This solution, based on the signal analysis, has been validated on the ET bench of Valtimet France, and can potentially be industrialized in the plant of Changzhou Carex Valinox Components Co. Ltd in China for its production of these corrugated tubes (Carex Corrugated Tubes).