http://www.iaeme.com/IJMET/index.asp 224 editor@iaeme.com International Journal of Mechanical Engineering and Technology (IJMET) Volume 9, Issue 13, December 2018, pp. 224–232, Article ID: IJMET_09_13_024 Available online at http://www.iaeme.com/ijmet/issues.asp?JType=IJMET&VType=9&IType=13 ISSN Print: 0976-6340 and ISSN Online: 0976-6359 © IAEME Publication Scopus Indexed POLY VINYL CHLORIDE PELLET PRICE FORECASTING USING ARIMA MODEL Adisak Nowneow and Vichai Rungreunganun Department of Industrial Engineering, Faculty of Engineering King Mongkut’s University of Technology North Bangkok, Bangkok. Thailand. ABSTRACT This research proposes a forecasting model to predict the appropriate price of the plastic pellets (PVC) .The price is affected by 2 factors, which are crude oil price and exchange rate .The analysis of these data in the last 10 years from January 2008 to December 2017 showed that the variation of the plastic pellet price, crude oil price and exchange rate .In order to increase the forecasting accuracy, this research applied ARIMA simulation model to forecast the PVC pellet price when using crude oil price and exchange rate as independent variables .The research started by studying and collecting data related to the factors affecting the PVC pellet price .Then, an analysis of the ARIMA forecasting model to predict the PVC pellet price was performed. In next step, Analysis the ARIMA forecasting model for PVC pellet price with time series of independent variables. After that, Forecasting of independent variable. And finally, Forecasting PVC pellet price. Results from the model were compared for their consistency using the mean absolute percentage error (MAPE) and the R-squared (R 2 ) in the final step .The results of this research showed that ARIMA (1,1,1) was the appropriate forecasting model for the plastic pellets price with 0.511 for the mean absolute percentage error and 0.923 for the R-squared. Key words: Poly Vinyl Chloride (PVC), Forecasting, ARIMA Model, PVC Pellet Price, Crude Oil Price, Exchange rate. Cite this Article: Adisak Nowneow and Vichai Rungreunganun, Poly Vinyl Chloride Pellet Price Forecasting Using Arima Model, International Journal of Mechanical Engineering and Technology, 9(13), 2018, pp. 224–232 http://www.iaeme.com/IJMET/issues.asp?JType=IJMET&VType=9&IType=13 1. INTRODUCTION Plastic pellet is currently a necessary raw material and is widely used in many industries . It is used as the main raw material for the production of various products such as packaging, variety of tools and equipment, film, pipes and other products . Plastic pellets are produced from long chain hydrocarbon compounds derived from crude oil refinery . These long chain hydrocarbons