Reliability analysis of Polytube industry using supplementary variable technique

The purpose of this paper is to compute reliability of Polytube manufacturing plant having four units using supplementary variable technique. The failure and repair rates of the sub-systems are variable. The mathematical equations are derived using Chapman-Kolmogorov differential equations which are formed using mnemonic rule from the transition diagram of Polytube manufacturing plant. The system of partial differential equations obtained has been solved using Lagrange's method and reliability of the system for the various choices of constant transition rates is solved numerically using Runge-Kutta fourth order. A sensitive analysis of subsystem is finally carried out to improve overall availability.