eng Science and Education Publishing American Journal of Mechanical Engineering 2328-4110 2018-12-06 6 4 148 158 10.12691/ajme-6-4-1 AJME2018641 article Eugene Peters Seleiyi 1 Shamagana Yizadi Musa pat4zad@gmail.com 2 Agbo Chidome Joseph 2 Tecchnical Department, Harcourt Adukeh Associates, Port Harcourt, Nigeria Mechanical Engineering Department, Nigerian Defence Academy, Kaduna, Nigeria The performance and reliability based analysis of process air compressor in the petrochemical industry was carried out. The lognormal model was used for reliability analysis, while the Weibull probability distribution and chi test technique were used to analyzed the sample test questions. The failure based results indicated that for every 1% increase in the lognormal probability, the failure rate increased by 2.4% when compare with that of the Weibull distribution. The Reliability indicates that the reliability of the system for 50days of operation is 36.8%. This increased to 38.8% at the MTBF of 365days. Therefore, there exist a relationship between the system reliability and the failure rate. Base on the chi square test at 0.05 and 0.01 levels of significance it was concluded that 'Most Machinery failures are lubrication oriented'. Therefore, careful preventive maintenance process that is condition based should be followed in order to improve the plant energy efficiency. http://pubs.sciepub.com/ajme/6/4/1/ajme-6-4-1.pdf reliabiity failure mean time to failure (MTBF) lubrication Weibull distribution lognormal probability chi test technique Air compressor