Kanban: A Lean Production Tool, Statistical Quality Control (SQC)

Lean production, WCM, agile manufacturing and other terms are essentially different names for the same manufacturing management philosophy. The origins of this philosophy can be traced to the Toyota Production System (though the creators of this system themselves state that they were inspired by Henry Ford). But today, most of its best practices are accepted as sound propositions worldwide. The essence of the philosophy is that manufacturers work towards continuously shortening two key processes-the order fulfillment process and the new product development process-through the elimination of activities that do not add value to the product. This results in an organization that can respond with agility to market changes.

The most famous lean production tool is the kanban-is Japanese for signal. The purpose of kanban is to signal a demand for items at an operation centre to an upstream operation centre.

What executives must understand is that there is nothing great about a ‘kanban system’ per se. A plant can implement a kanban system without quitting down .on inventories by simply using a larger number of kanbans.

As discussed in earlier the challengelies in creating the organizational climate in which the kanban serves as a useful information tool for the shop floor. A pull system can, in fact, be implemented electronically, without paper kanbans being used.

Statistical Quality Control (SQC)

The idea behind SQC is continuo interesting actionable results. In a famous case, quality expert J.M. Juran recalls how a Pareto analysis of defects in a brand of photocopiers revealed that nothing had changed significantly in 10 years. It took Juran to point out to the company that this indicated a singular of market sensitivity. Operationally, the most common SQC tool used is the control chart. The purpose of a control chart is to sound an alert when a process starts producing an output outside the acceptable range it is capable of adhering to. This range is measured and specified in terms of upper and lower control limits.

The output from the process is continuously monitored and plotted on a chart that indicates the control limits. Any abnormality in the output-such as a point outside or close to the control limits, or a trend towards either of the limits-serves as a trigger to the person operating the process that corrective action has to be taken.

The use of statistical tools was initiated by Shewhart in the 1930s, and later popularised by Deming and Juran. Their contribution to the emergence of Japan as a global manufacturing powerhouse is widely recognized.

However, some leading Japanese practitioners are skeptical about these tools. They strongly advocate an effort towards zero defects through the use of Poka Yoke, practical tools for mistake-proofing operations.