In the metal and mineral industry, different empirical techniques are used to estimate the remaining thickness of the lining within an operating furnace. The disadvantage and costly factor when using these methods is that production needs to be halted._x000D_
Hatch has developed an accurate and reliable technique based on stress wave propagation principles to determine the condition of the remaining lining whilst the furnace remains online and operational._x000D_
The technique involves test data collected and compiled to generate 3D imagery used to assist operators and maintenance planning personnel with valuable information showing areas of metal penetration in the lining, remaining lining thickness, exact location of voids, cracks, poor contacts and deterioration due to chemical attack._x000D_
In this paper, the principals of the AU-E technique will be explained both theoretically and practically. In addition, the use of ultrasound technology for determining the condition of copper cooling elements will be briefly addressed._x000D_
FORMAL CITATION:Spreij, M, Sadri, A and Smith, S, 2006. Acousto ultrasonic-echo (AU-E) and ultrasound technology - determination of the lining and cooling element condition of operational furnaces, in Proceedings Metallurgical Plant Design and Operating Strategies 2006, pp 290-300 (The Australasian Institute of Mining and Metallurgy: Melbourne).