OK Adi,
Maintenance section would be defined Reorder point and safety stock level according to criticality of spares.
The reorder point should cover the average material requirements expected during the replenishment lead time.
The safety stock exists to cover both excess material consumption within the replenishment lead time and any additional requirements that may occur due to delivery delays. Therefore, the safety stock is included in the reorder level.
The following values are important for defining the reorder point:
- Safety stock
- Average consumption
- Replenishment lead time
The following values are important for defining the safety stock:
- Past consumption values (historical data) or future requirements
- Vendor/production delivery timelines
- Service level to be achieved
- Forecast error, that is, the deviation from the expected requirements
And on the behalf of spares requirement you can decide it how you schedule of running MRP.
As per my Experience run two days MRP in weekly for better procurement process.