Spare parts reorder & stock coverage

Reorder point = ceil(daily usage × lead time + safety stock). Inventory position = on hand + incoming − reserved/backordered. Target = ceil(daily usage × (lead time + coverage period) + safety stock). Suggested replenishment = max(0, target − inventory position).

This simple policy assumes reasonably steady demand and manually chosen safety stock. Intermittent critical spares need equipment-risk and failure-history review. Incoming orders count toward inventory position but not physical days of cover; check their promised dates separately. Reserved and backordered quantities should not overlap. Reorder trigger uses inventory position at or below the reorder point.