Implementation of Inventory System by P (R, T) Model with Differenced Time of Known Priced Increase at PT Inti Vulkatama
ABSTRACT: PT IntiVulkatama
is a manufacturing
company forthe tire
retreading. The demand of the
product is probabilistic causing the PT IntiVulkatama often experience shortages
of raw material inventory (backorder) that could produce the company to lose the
trust of its customers. Currently, PT IntiVulkatama address this problem using a
forecasting method by looking at the demand of the past. PT IntiVulkatama must have
a better inventory system that can minimize the expected total cost especially when
facing the condition of differenced time of known priced increase for some of the
raw materials.
It is suggested
that a good
method for solving
the problem is
fixed order interval system. With
this system, PT IntiVulkatama can perform a joint order with a certain time
interval and the order size
is adjusted to
the difference between
the maximum inventory and the amount of stock that is available when the
order is made. In addition, PT IntiVulkatama should able to determine the size
of special order when one or some
of raw materials
experiencing the differenced
time of known
priced increase. Study has derived a model that can be used when the
company experienced the priced increase for two raw materials.
Based on data, PT IntiVulkatama should make a joint order for its six raw
materials with a time
interval of 1.12
weekwith each order
size reaches the
maximum of the inventory. The result of the price
increase problem is a method of the differenced time of known priced increase
with the savings value greater than zero. The study results in a recommendation
that not to perform a special order due to the saving is less than the total
cost.
Author: Y M Kinley Aritonang,
Ph.D
Journal Code: jptindustrigg140002
