Supply Chain Management :: The impact of demand variances on safety inventory: Case Study PT. GE Lighting Indonesia - Jogjakarta

MIRANDA, Ade, Adi Djoko Guritno, Dr.Ir.,MSIE

2005 | Tesis | Magister Manajemen

Penelitian ini mengfokuskan pada pembahasan supply chain management yang bertujuan untuk memaparkan dampak keragaman (variansi) permintaan pada cadangan pasokan. Permintaan sangat penting dikarenakan ketidakpastian yang akan berdampak pada perubahan di luar dan dalam dari operasi sebuah perusahaan. Hal ini dapat menyebabkan perenc anaan menjadi tidak efisien serta akan membuat pelaksanan tugas menjadi tidak tepat. Dalam bahasan lain juga dibahas secara lebih dalam tentang waktu tenggang (lead time). Lead time adalah sebuah faktor yang harus diperhatikan oleh perusahaan. Semakin besar (lama) lead time akan membutuhkan produk semakin banyak. Penelitian ini, beberapa asumsi digunakan dia ntaranya adalah ketersediaan produk diasumsikan sebagai ketersedian bahan mentah (raw material). Untuk analisa permasalahan digunakan tiga metode penghitungan yaitu Fill Rate (fr), Cycle Service Level (CSL), and lead time , dimana masing-masing menunjukkan berapa banyak bahan mentah yang harus dimiliki oleh perusahaan dalam satu periode perencanaan produksi. Penelitian dilakukan di PT. GE Lighting Indonesia (GELI) dengan fokus pada tiga produk yaitu Incandescent Lamp (INC), Fluorescent Lamp (FL) and Fluorescent Circle Lamp (FCL). Beberapa data dikumpulkan diantaranya adalah data permintaan, lead time, Some, standard deviation of demand, service level, Reorder Point (ROP), and lot size. Dengan data dan metode perhitungan yang ada. Didapat hasil bahwa dengan tingkat service level yang sama, fill rate membutuhkan cadangan pasokan yang lebih banyak dibandingkan CSL. Dengan metode lead time, semakin panjang lead time, memerlukan cadangan pasokan yang lebih banyak. Dari sini dapat disimpulkan bahwa perlu unt uk GELI melakukan perhitungan cadangan pasokan dengan parameter ketidakpastian permintaan dan lead time sehingga produksi dapat direncanakan dengan baik.

This research paper focuses on supply chain management in which the aim is to explore the impact of demand variances on safety inve ntory. Demand is deemed very important due to its uncertain circumstances that would affect on the changing of internal and external of company’s operation. Variances might be occurred in doing a business that might be cause on ineffectiveness of planning and also resulting improper execution. Whilst, an the same time depth discussion of lead time is also conducted due to its role a part of facets that company should concern. The bigger lead time would require the bigger product availability. Some of research assumption are utilized one among others is the terms of product availability is viewed as raw material. The research uses three methods of measurement, Fill Rate (fr), Cycle Service Level (CSL), and lead time basis. It will also explore the differences among those methods in terms of the amount of safety inventory resulted from measurement and entails how many raw material company should hold for one period of production planning. Research is conducted at PT. GE Lighting Indonesia (GELI) and discussion focuses on three different kinds of product which is Incandescent Lamp (INC), Fluorescent Lamp (FL) and Fluorescent Circle Lamp (FCL). Some of data are utilized – demand, lead time, standard deviation of demand, and standard deviation of lead time, service level, Reorder Point (ROP), and lot size. Using data and methods available, research found that with the same number of service level, fill rate simultaneously require higher amount of safety inventory. On the other hand, the longer lead time will also yields higher amount of safety inventory. Hence, it is necessary for GELI to conduct proper measurement of demand and supply uncertainty to attain better planning production.

Kata Kunci : Supply Chain Management,Safety Inventory, supply chain management, safety inventory, Fill Rate (fr), Cycle Service Level (CSL), lead time.