Lean Principles Can Be Counter-Intuitive

Lean Principles Can Be Counter-Intuitive

  • Posted by admin
  • On January 30, 2015
  • Comments

Lean Principles Can Be Counter-Intuitive


Lean is a method of production that you may be familiar with already. Simply put, it’s a system by which waste is reduced and production is focused on providing exactly what the customers need using a minimum amount of both resources and time.


Some of the principles of Lean make sense and are intuitive. For example, the concept of error-proofing makes sense to the majority of us. However, one Lean concept that is consistently difficult for many business people to understand is the philosophy regarding machine utilization.


Many business owners, operations managers, and controllers would be quick to assume that their businesses will profit by constantly running all of their machines to produce the maximum number of parts. However, the concept of customer demand has to be considered. So does the concept of bottlenecking, or the backing up of the production process because one process is faster than another in producing parts.


In a business or manufacturing plant that uses the Lean system of maximizing efficiency, it is rarely advisable to overwork employees or machinery. In order to understand why, let’s examine how one piece flow works. Included in implementing one piece flow is producing to takt. Takt time is defined as the average unit production time that must be achieved in order to meet customer demand. As a simple example, if a work day is eight hours long and the customer needs 24 parts per day, the takt time is 1/3 of an hour, or 20 minutes.


Conventional wisdom suggested that machines should be run at full capacity in order to decrease the fixed cost per part. However, Lean suggests otherwise. The Lean system would indicate that producing at a rate greater than takt time is a form of waste because excess parts pile up, sometimes at an alarming rate.


As an example, let’s consider the CNC machining department of a small manufacturer. The CNC machines were running at full speed independent of customer demand or the capacity of up or downstream processes. Due to this, significant inventory was building up between the CNC department and the next process. Excess inventory led to wasted products and idle workers.


When the backup of excess products was discovered, the problem became how to address the issue. It was a matter that led to a major debate between the company president, controller, engineering manager, and even outside consultants. The suggested solution was to shut down the machinery for several days. That may seem like a loss of profits but, according to the Lean system, it was actually preventing waste. Still, it was a counter-intuitive move, which wasn’t easily agreed upon.


The situation described above is very common. It is easy to say that your company believes in using Lean to maximize production efficiency. However, it is not always easy to fight your basic instincts and follow the Lean system. Nevertheless, the positive results are clearly proven when the system is implemented properly.


Leave Reply

Your email address will not be published. Required fields are marked *