Expendables are parts that are not repaired and scrapped whenever they fail and replaced with a new working unit. These parts are generally cheaper parts and are ordered in batches or available only in boxes and not individually. When to place the order and how much to order is important to determine as there will be a lead time between when the order is placed and when the order is received. Other factors such as expected demand and warehouse replenishment policies also affect this decision.
The Revision of Expendables Settings function in D-SIMSPAIR calculates the Economic Order Quantity (EOQ) and the Reorder Point (ROP) automatically from the available part and supplier data. As the demand for the expendable part may change over time due to change in reliability or flight network, it is required to adjust the EOQ and ROP on a regular basis. This also applies in case there are changes in the supply chain of the part.
Please also see Expendables Setting Analyser