Understanding the Principle of Flow in Lean Manufacturing

Understanding the Principle of Flow in Lean Manufacturing

“Originally developed as a methodology to make production processes highly efficient, lean techniques have been adopted by more than 72 percent of machine shops across the country. For many of these, the techniques have helped them to dramatically increase their competitive edge, while continuing to remove wasteful practices and contribute to the bottom line.”

Lean techniques are not limited to machine shops, productions plants, or manufacturing companies. They can help any business motivated to produce products and deliver services using as few resources as possible, while eliminating as much waste as possible. No matter the type of business, whether  a restaurant, bakery, , small offices,or  large processing plants all follow the same five Principles of Lean from the Toyota Production System. These principles are:

  1. Understand value from the customer perspective
  2. Understand the Value Stream
  3. Make the Value Stream Flow
  4. Create Pull
  5. Continuously Improve

Each of these concepts is related to the others.The focus of this blog is on  flow, and the seven flows of manufacturing, barriers to flow in organizations, and how to improve flow.

Defining Flow

Flow is how work progresses through a system. When a system is working well, or having “good” flow, it tends to move steadily and predictably, whereas, “bad” flow means the work starts and stops. Every time there is a breakdown in the flow, chances of accumulating waste increase.  One goal is to Sstrive for a consistent flow which generates more reliable delivery, and greater value to customers, teams, and stakeholders.

Identifying the Seven Flows of Manufacturing

Mike Wroblewski, Senior Operations Consultant for Gemba Consulting,explains in his Reliable Plant blog, the Seven Flows of Manufacturing by his Japanese sensei, Nakao-san:

  1. The flow of raw material
  2. The flow of work-in-process
  3. The flow of finished goods
  4. The flow of operators
  5. The flow of machines
  6. The flow of information
  7. The flow of engineering

Companies who successfully integrate the principles of Lean Manufacturing understand that when each of these seven types of flows are working in harmony, they are increasing their odds of producing finished goods and services that require little to no corrective action. Keeping production running, in such a smooth fashion, also helps to ensure that a company is creating efficiencies.

There is a direct relationship between creating efficiencies that enhance overall business performance and increasing profitability. These are  just some of the ways that a company implementing lean manufacturing can put notable distance between themselves and their competitors.

Barriers to Flow

If you want to improve flow, first remove all barriers. Figliolino Venanzio, Founder of Lean Six Sigma University, outlines both physical and intangible barriers to flow:

Examples of Physical Barriers to Flow:

  1. Distance: Rather than transporting individual items, they are collected and shipped as a group
  2. Long Setup Times: When changing over tooling takes a long time, larger batches are run
  3. Batch-Oriented Machines: Some machines are designed to be most efficient with large runs.
  4. Poor Maintenance: Machines that break down frequently disrupt flow.

Examples of Intangible Barriers to Flow:

  1. Unreliable Deliveries: When there is no trust that parts will arrive on time, extras are kept on hand
  2. Unreliable Quality: If people think that many parts will be unsuitable or will require rework, extras will be kept on hand
  3. Approval Processes: The approver is seldom standing by, so work is piled up until the next opportunity to get the go-ahead
  4. Lack of Faith: Some people just don’t believe flow is possible, so don’t even try
  5. Resistance to Change: Some people think flow might work, but like things to stay the same.

Once companies identify and prioritize all of the barriers to flow, they are ready to implement the changes designed to improve the overall process of flow.

Improving Flow

Lee Candy, creator of Educational Business Articles, suggests  6 pointers to help companies develop flow within their processes:

  1. Map the process
  2. Identify and log all problems process owners experience
  3. Identify all waste in the current process
  4. Map an ideal state – the perfect process achieved in absence of all constraints
  5. Develop an action plan
  6. Actively monitor the new processes put into place by creating performance measures

A final point to make about improving flow is the necessity of training and educating employees. All employees must understand, and appreciate, how essential it is to keep a good flow going! Odds are that once changes are made to enhance the flow, employees will recognize these changes and begin to see that their jobs may have become physically and/or psychologically a bit easier to do!