The first stage of implementing the JIT manufacturing techniques is to rearrange the factory floor away from the batch production functional layout towards a production layout using low lines with a functional plant layout production through a No. of special departments that normally contain a group of similar machines.
Products are processed in stage batches so as to minimize the set times when machine settings are changed between processing batches of different products. Batches move via different and complex routes through the various departments, traveling over much of the factory floor before they are complete.
Each process normally involves a considerable amount of waiting time and which much time is taken transporting items from one process to another.
A further problem is that it is not easy at any point in time to determine what progress has been made on individual batches and therefore detailed cost accumulation records are necessary to track work in progress. This results in long manufacturing cycles and high work in progress levels.
The JIT solution is to reorganize the production process by dividing the many different products that an organization makes into families of similar products or component. All the products is a in a particular group will have similar production requirement and routing. Production is necessary used so that each production family is manufactured in a well-defined production cell based on flow line principles. In a production how lines specialist department containing similar markets no longer exist. Instead groups of dissimilar markets are organized into products or component family flow lines that function like an assembly line.
For each production lines the market are placed close together in the order in which they are required by the group of products to be processed. The items in each product family can now shift one at time from process to process more easily, thereby reducing wip, and lead time.
The aim is to produce products or component from start to finish without returning to the stock room or stores