Just in Time Manufacturing
Just in Time Manufacturing (JIT) - also known as “lean manufacturing” refers to a system of manufacturing in which products are not built until the product is ordered and paid for. Some companies that have successfully implemented JIT include Toyota, Dell and Harley Davidson.
JIT’s main philosophy is to eliminate waste - wasted inventory, wasted stock and wasted time. By creating and deliverying products quickly when consumers request them excess inventory is eliminated, customers receive their orders quicker and the manufacturer doesn’t need to keep a large inventory of stock parts.
Below are just a few examples of successful JIT implementations.
Toyota is considered by many to be the poster child for JIT success. The Toyota production strategy is highlighted by the fact that raw materials are not brought to the production floor until an order is received and this product is ready to be built. No parts are allowed at a node unless they are required for the next node, or they are part of an assembly for the next node. This philosophy has allowed Toyota to keep a minimum amount of inventory which means lower costs. This also means that Toyota can adapt quickly to changes in demand without having to worry about disposing of expensive inventory.
Important Factors to Toyota Success:
- Small amounts of raw material inventory must be kept at each node in production, so that production can take place for any product. These parts are then replenished when they are used.
- Accuracy of forecasting is important so the correct amount of raw materials can be stocked.
Dell has also leveraged JIT principles to make its manufacturing process a success. Dell’s approach to JIT is different in that they leverage their suppliers to achieve the JIT goal. They are also unique in that Dell is able to provide exceptionally short lead times to their customers, by forcing their suppliers to carry inventory instead of carrying it themselves and then demanding (and receiving) short lead times on components so that products can be simply assembled by Dell quickly and then shipped to the customer.
Important Factors to Dell’s Success:
- Dependable suppliers with the ability to meet Dell’s demanding lead time requirements.
- A seamless system that allows Dell to transmit its component requirements so that they will arrive at Dell in time to fulfill its lead times.
- A willingness of suppliers to keep inventory on hand allowing Dell to be free of this responsibility.
Harley Davidson’s use of JIT is mostly characterized by its transformation in the late World War 2 era from an inefficient manufacturer that solved all of its problems with extra inventory to a nimble manufacturer able to meet demand and provide short lead times.
Results of Harley Davidson’s JIT Implementation:
- Inventory levels decreased 75 percent.
- Increased productivity.
Harley Davidson’s success with the implementation of JIT had a lot to do with the fact that when JIT was put into practice, process problems could no longer be hidden by costly inventory that helped to meet ship dates. The inefficiencies in the processes were quickly identified and solved.