What is Lean Manufacturing?

What is Lean Manufacturing?
What is Lean Manufacturing?
What is Lean Manufacturing?

What is Lean Manufacturing?

The concept of Lean manufacturing has been around for centuries. It can be traced back to King Henry III watching galley ship production in 1574, Eli Whitney and the idea of interchangeable parts used to manufacture muskets during the late 1700s, and Henry Ford’s Model T assembly line. It wasn’t until after World War II that Toyota introduced modern Lean production methods.

It would be several decades after Toyota employed modern Lean manufacturing principles that the phrase “Lean Manufacturing” was coined in the book, “The Machine That Changed the World”. Based on the largest and most thorough study ever undertaken of any industry – MIT's five-year, 14-country International Motor Vehicle Program – this book describes the entire managerial system of Lean production.

The three issues of Lean.

In the book, James P. Womack  and Daniel T. Jones describe Lean manufacturing principles and how companies can mimic Toyota’s success “to transform traditional enterprises into exemplars of lean success.” According to the authors, three issues are at the heart of Lean success – purpose, process and people. Purpose is the understanding of the company’s goals. Process is the understanding of the steps the company will take to achieve its goals. People is the understanding that every member’s contribution matters.

Lean’s four goals.

  1. Improve quality.
  2. Eliminate waste.
  3. Reduce time.
  4. Reduce total costs.

The seven categories of waste.

Removing waste both inside and outside of a company is fundamental to a Lean system. Below are the seven common categories of waste. (Six Sigma includes “skills” as the eighth waste – "underutilizing capabilities and delegating tasks with inadequate training"):

  1. Transport
  2. Inventory
  3. Motion
  4. Waiting
  5. Overproduction
  6. Over-processing
  7. Defects

The five Lean principles.

  1. Specify what does and does not create value from the customer’s perspective. An activity for which a customer is happy to pay is defined as a value add. On the other hand, a non-value-adding activity is one in which the customer sees no benefit. Non-value-adding activities are wasteful and should be targets for elimination.
  2. Identify the value stream. 
  3. Make the actions that create value flow – without interruption.
  4. Only make what is pulled by the customer. Pull includes all activities being undertaken according to and at the rate of actual customer demands.
  5. Strive for perfection by continually removing successive layers of waste as they are uncovered.

Organizations cannot pick and choose which of the five Lean principles to employ. All five processes are required to be successful. Additionally, the five-step process is an iterative process. Companies cannot be content with one pass through the process. They need to attack different areas until a satisfactory amount of waste has been eliminated and a satisfactory amount of value has been created for the customer.

How to launch Lean initiatives in your company.

Not everyone at your company will actively embrace new Lean manufacturing principles. Often, employees are introduced to these desired Lean events by senior leaders who are not involved in the nitty-gritty of manufacturing processes. This disconnect can lead to skilled employees actively or passively refusing to comply with new methodologies being imposed by senior leadership. If you manage employees who have been asked to embrace a new Lean journey, here are some tips to help you encourage compliance.

According to Industry Week, you must do three things when embarking on a Lean journey to address skilled employees who refuse to embrace new continual improvement initiatives.

  1. Train immediately. For Lean manufacturing success, everyone – at every level of the business – should be trained on new initiatives within seven to 10 days of introduction. According to Larry Fast of Industry Week, “This helps to educate the masses very quickly as well as eliminates any excuses for non-conforming behaviors going forward.”
  2. Meet with noncompliant employees. Skilled employees who exhibit active noncompliance are those who vocalize their refusal to participate; these employees may try to recruit others in their movement. The best course of action is to meet with these individuals to remind them of the new Lean protocol and what’s expected of them. Passive employees – those who use excuses such as, “I haven’t had time” – should also be addressed. Passive employees are often more difficult to root out, but these individuals can be just as detrimental to Lean success as active, noncompliant personnel.
  3. Reward compliance. Reward employees who have adapted quickly to new Lean initiatives. Acknowledge these employees in front of their peers for their specific accomplishments, but make sure these public acknowledgments focus on what their peers can directly affect. This way, you are both rewarding and inspiring others to achieve Lean manufacturing success.

Want to learn even more about Lean manufacturing? Kettering University's Lean Manufacturing online master's degree program delivers the skills you need to improve quality output, streamline processes and reduce waste. Learn more.