One such method, which is presently commanding much attention and achieving notable results, is the Condition Monitoring followed by predictive or condition based maintenance. Under this concept the maintenance is based on the actual condition of the plant and not by age old breakdown or preventive maintenance concept. The benefits of Condition Based Maintenance are many fold, e. g.

• Accurate knowledge of health of the machine helps maximise the time between overhauls.

• Timely correction of the faults eliminates catastrophic failures. It allows maintenance lead time and improves operational reliability.

Most of the processes in an iron and steel industry are thermally related which involve the introduction, evolution or containment of heat in very large quantities. One of the most suitable condition monitoring techniques for maintenance of steel plant equipment is Thermography. M/s. Tata Steel is a pioneer in the field condition based maintenance by thermography. Thermography is a technique of producing live thermal pictures of objects based on infrared radiations received from them.

The authors in this paper has attempted to present some of their hands on experience in Tata Steel in the application of this versatile technique for steel plant maintenance. Some of their work includes

• Prediction and extension of life of refractory lined vessels.

• Inspection of blast furnaces and coke ovens.

• Detection of faulty electrical components.

Thermography is a modern technique which has great relevance in the condition monitoring field. The availability of real-time thermal surveillance has added a new and powerful dimension to plant condition monitoring in many production and maintenance areas of industry. Applications from the steel industry illustrate the versatility, reliability and cost effectiveness of the same. It is in fact a potential, the application areas are on the increase according to the problems being faced.