The best known Lean term – Just in Time

Just in time is one of the best known Lean terms but how does it apply to you and your business?

Today we will review the basics of Just in Time (or JIT as it is commonly known)

The Automotive industry in famous for it’s just in time approach to delivery by it’s suppliers. The basic principle is to have the right amount of products, where we need it and when we need it. And, of course, to the acceptable quality level. Sounds like a simple enough concept.

The auto industry has refined and refined their processes along with their suppliers to make the JIT process work. Then they have decreased the deliver intervals into a measure of hours, not days or weeks. While this is all very well for a car company with high volumes and obedience suppliers, but how does this apply to you?

The basics of just in time are along the same lines as the previous articles on kanban and two bin systems. You may even need a kanban or two bin system to control your just in time deliveries.

First we need to understand the main value stream – the backbone of your manufacturing process or the one that would be run done a moving line, with everything else feeding into it, rather like a fishbone diagram. Then we need to understand the feeder lines and the parts that are needed to be fed into the main manufacturing process.

Once we have a list of parts and we know where they are needed in the build process, we need to determine the right amount and when they are needed. To do this we need to gather information for each part number or line item:
– amount used per assembly
– how quickly we use them
– how quickly can our supplier resupply them
– how reliable is our supplier

This data should look familiar; it’s the same information we need when figuring out a kanban system. With this information we can begin to build the picture of how we need our parts to be delivered into our main manufacturing process. So with the basic principle of having the right amount of products, where we need it and when we need it, and some basic information about our manufacturing processes and parts supply, we can start to get an idea of what a Just in Time system would look like in your business. Next we will look at the considerations for implementing a Just in Time system.