The purpose of this paper is to describe the availability of plate manufacturing system of a steel industry. This system consists of six principal subsystems viz. furnace, roughing mill, tandem mill, pinch roll, down coiler and strapping machine. Failure and repair rate of these subsystems affects the overall system availability. Analysis has been calculated using Supplementary Variable Technique (SVT). Failure rates have been assumed constant whereas, repair rates are varied. ChapmanKolmogorov differential equations have been developed from the transition diagram of the plate manufacturing system, using mnemonic rule. These equations are then solved using Lagrange's method. The transient state availability of the system and Mean Time Between Failure (MTBF) have been calculated numerically. The conclusions drawn at the end reflect the criticality of a particular subsystem and also assist the plant management in deciding maintenance priorities for optimum utilization of the resources.
