| The inventory system which is used currently isn’t effective because for most times couldn’t provide the need of components. The correct maintenance programme should be supported with good components inventory preparation. The correct supply of components should also minimize inventory cost. The cost of inventory is determined to estimate the purchasing budget for 2 years. Critical engine is determined using OEE calculation. The result of OEE calculation in selected group of is mori seiki machine type NV4000 with OEE value 62,05%. The group of selected machines consists of MC 039, MC 040, MC 043, and MC 053. Critical components are determined using pareto principal. First summarize the engine’s components replacement in January 2016-March 2016. The critical engine is chosen using pareto principal based on frequency of components replacement. Then 20 critical components which used as calculation data are determined. Interval of components replacement is determined using statistical test of distribution on software Minitab 15, using TTR and TTF components also using Weibull, exponential, normality, and lognormal distribution. The calculation of the parameters is done by using Maximum Likelihood Estimator (MLE). Furthermore, for the value component replacement interval with the criteria minimizing downtime. Calculation of component inventory using the Q and P method. Q method that is used is basic EOQ. The result of the calculation determining the method of calculation of Q is used as model for all critical components. Furthermore, the calculation of purchase cost by calculating with MRP planning for 2 years with total inventory cost Rp. 3,050,655,600. |