Definicja long-lead item

A material where the elapsed time from order to delivery is so large that special planning and often contractual provisions are required to ensure the availability to a given schedule. In project-based manufacturing, the procurement of long lead items is initiated in an early project phase prior to completion of the final product design. These materials can be complicated assemblies requiring design or engineering effort, e.g an aircraft wing, or raw materials that require sophisticated manufacture e.g. specialist metals.They are generally procured as make-to-order items and are not generally held as in stock material.