In sand blasting systems, the cleaning cost plays an essential role and greatly relies on many parameters e.g., nozzle diameter, nozzle lifetime, cleaning rate, etc. This study presents the procedure to compute the cleaning cost based on the price of cleaning system, price of abrasive, and price of nozzle when sand blasting with silicon carbide nozzles. The exchanged diameter of the nozzle was figured out by minimization technique of the cleaning cost function. Furthermore, using the experimental design method, the behaviors of seven input variables to the optimal exchanged diameter of the nozzle were examined. Using Minitab@19 for the experimental design was also proposed. The results illustrate that the input variables not only have on the optimal exchanged diameter of the nozzle, but also the interactions of these variables importantly affect the output variable. In addition, the mathematic equation was established in order to predict the optimum replaced diameter of the nozzle. This is greatly meaningful for sand blasting process due to decrease the cleaning cost.