What is Just In Time?

Just in Time is one of the elements that determines a supplier’s ability to be flexible to customer orders. It means being ready to produce and deliver a given product to the customer in a small quantity within a short time. This prevents the creation of stock that is actually a loss (MUDA in Japanese). It forces the production of so-called short runs. The introduction of short production runs is currently the direction of development for most manufacturing companies – it allows for the individualization of customer orders, an increase in the number of variances on production lines and greater competitiveness of entrepreneurs.

Changing the production process from long run to short run cycles is not an easy task for a resource manager on a production line. Changes are difficult to implement and often time consuming. One of the main reasons for unwillingness to change is the increased number of so-called changeovers. In order to overcome the resistance and aversion to change, one should optimize the part of the process which is changeover. One should use a tool known as SMED – Single Minute Exchange of Die – in order to effectively reduce set-up time.

Benefits of introducing the SMED concept:

• Increased machine utilization,
• Increased flexibility in customer order fulfillment capabilities,
• Reduced number of incorrect changeovers,
• Reduced number of defects due to machine start-up,
• Increased operator safety at the workplace,
• Decrease set-up costs (amount of consumables and components used) by reducing set-up complexity,
• Increasing the versatility of machine operators.

Remember, however, that not all processes can achieve a single-digit changeover time. The name of the method (Single Minute Exchange of Die) is due to its author – a Japanese engineer – Shigeo Shingo. The engineer managed to reduce the press changeover time at Toyota from 1 hour 40 minutes to 3 minutes. The success of changeovers prompted Shigeo Shingo to develop a systematic method, the application of which has made it possible to significantly reduce changeover times in other processes as well.

The SMED tool is based on 3 main steps. The first step consists of discovering changeover losses, the second step involves analyzing the losses observed, and the third step involves preparing proposals for technical and organizational changes.

The SMED approach is characterized by:

• Consistency,
• A sense of observation combined with innovation,
• Openness to any changes.

Changes should be implemented on a step-by-step basis – starting with the least costly ones and ending with major organizational changes and technological solutions. Implementing SMED on production lines allows you to believe in the success of the JIT approach, as it is the first element that will fundamentally facilitate its use. Changes in the organization of production processes will be noticeable not only to employees, but also to external customers.