Analisis Bullwhip Effect untuk Produk Pertalite dan Pertamax dengan Metode Periodic Review (Studi Kasus: PT Pertamina RU IV Cilacap)

Abstract

PT Kilang Pertamina Internasional - Refinery Unit (RU) IV Cilacap is a refinery that has
processed crude oil into BBM (refined fuel oil), non-fuel, and petrochemical products since 1974.
Refinery Planning & Optimization (RPO) is one of the functions in the Supply Chain &
Distribution section at the refinery. The task of the RPO is to manage, control, and regulate daily
production and distribution operations based on STS (production planning), and to maintain and
control the company’s supply chain. Pertalite and Pertamax products are produced based on the
STS provided by the Refinery Planning section, in which production constraints in the field and
fluctuating STS cause a deviation between plan and realization, so that inventory and production
policies are not properly controlled. The purpose of this research is to analyze the existing bullwhip
effect for Pertalite and Pertamax products in 2022 and provide optimal production policies to deal
with the bullwhip effect (BE) that occurs with the periodic review method. The results show that
the existing BE value is considered not good because most of the values are greater than 1, while the BE value after implementing production policies with the proposed method is known to be
better. Therefore, we can conclude that it is recommended to apply the periodic review method to
overcome the BE. By implementing the production and inventory policy for a BE value < 1 for
Pertalite products, the amount of safety stock required is 49,42 mb with a base stock level of 129
mb, z (service level) 95%, and a lead time of 2,5 days. Meanwhile, for Pertamax products, it is
known that safety stock should be 53,50 mb with a base stock level of 73 mb, z 95%, and a lead
time of 2 days.