Evaluation of Copper Stave Remnant Thickness in Blast Furnace Using Ultrasonic Method

Blast furnace is one of the most important parts in an integrated iron and steel industry where smelting of iron is carried out. Staves are essential part of a blast furnace, which increase blast furnace campaign life by providing cooling in order to protect the external steel shell from heat as well as to maintain the inner profile of the blast furnace. Under high temperature environment, stave wear takes place due to downward and upward motion of materials and hot gases, respectively. Thickness of the stave should be monitored on a continuous basis to prevent any catastrophic failure. In this study an ultrasonic test method was adopted to carry out the thickness measurement of copper staves. Measuring copper stave thickness involves two challenges; direct accessibility from the outside and its inherent intricate geometry. In this paper, a complete methodology comprising ultrasonic sensor and fixture mechanism to overcome the above challenges is discussed. An innovative stave thickness measuring device was first developed and calibrated in the laboratory, which was then used to measure the remnant stave thickness of a running industrial blast furnace. The results were verified by hole drilling method that proved the developed methodology as a reliable one.