| Written by Mark Buzinkay
What is the Toyota Production System?
As described by Takahiro Fujimoto (1), the Toyota Production System (TPS) is not the result of a grand design but instead emerged over time as Toyota people devised countermeasures and solutions to a succession of crises. In other words, the way Toyota produces is always a work in progress, and learning it is a never-ending process as the content keeps changing.
TPS works in many facets and implements different strategies. Some elements are:
- Just-in-time: Delivering the right items in the right quantities at the right time without relying on inventory to do it.
- Jidoka: Making production machinery progressively easier for operators to use through incremental automation and stopping it automatically when it malfunctions.
- Flow: Removing interruptions in the movements of materials and information from the supplier, through the plant, and to the customer.
- Kaizen: Working every day to make operations better. It means continuous, incremental improvement constantly pursued.
Lean manufacturing principles, including the Toyota Production System (TPS), have been widely adopted across various industries worldwide. A 2011 study by Compdata found that 71.6% of 1,100 surveyed manufacturing companies had implemented Lean practices in their operations. Additionally, 58.2% reported using Six Sigma methodologies, with a significant overlap between the two approaches. (7) Another survey from 2010 indicated that 69.7% of manufacturing companies utilized Lean manufacturing practices, with specific methodologies such as 5S programs (69.2%), Six Sigma (58.6%), and Kaizen (55.7%) being particularly prevalent. (8)
While these studies highlight substantial adoption rates within the manufacturing sector, comprehensive and up-to-date global statistics encompassing all industries are limited. Nonetheless, the available data underscores the significant penetration of Lean and TPS methodologies in manufacturing operations worldwide.
What is Gemba in the TPS?
Gemba is a Japanese word meaning "the actual place". In manufacturing, it is the factory floor. Market prices for products and the costs of materials, energy, and outside services are largely outside manufacturers' control. The TPS approach is to pursue profitability by improving work on the production floor instead of raising prices, pressuring suppliers for concessions, or buying new technology.
As everything happens on the factory floor, it is the place where to look for improvements. First of all, understanding a process is crucial before any improvements can be applied. A deep understanding comes from participation in and observation of the process, not by studying the process in a theoretical way. Process documentation such as charts differ very often from the factory floor reality and don't reveal the details necessary for a deep understanding of the process.
A Gemba walk is a (daily) exercise to observe the manufacturing process to happen. A Gemba walk is a continuous study of the production steps, offering insights into the minor details of transformation and handling (read more: the Gemba walk meaning).
Observing a process is combined with asking the right questions to the people involved in the process, such as:
- What are you responsible for?
- How does this task align with company goals?
- What is the standard for this task?
- How did you learn to complete this task?
- Why do you do this specific task like that?
- If you had it your way, how would you do this task?
- What happens if equipment, tools, or materials are unavailable?
In preparation of a Gemba walk, create a Gemba walk checklist and a Gemba walk template.
Now that we know what a Gemba walk is, let's head to some Gemba walk examples...
Gemba Walk Examples: Hidden practices
Gemba walks offer a valuable opportunity to uncover hidden factory issues that might remain unnoticed within a plant. The term "hidden factory" refers to informal, undocumented processes that workers rely on, which can significantly impact quality and safety. By directly observing operations and engaging in conversations with operators, leaders can identify these hidden processes, understand why they are being used, and determine what changes might be necessary.
For example, one plant was moulding coolant recovery bottles with a small tab on the bottom designed to help position the bottle on the vehicle fender during installation. When an injector pin in the mould broke, the tabs began to eject unevenly, often bent from the warm plastic mould. An operator noticed this issue and started manually straightening the tabs with his thumb to ensure they conformed to specifications. However, this informal process posed a hidden risk. When the operator was absent, his replacement did not bend the tabs back into position, resulting in multiple boxes of defective bottles being shipped to customers. The supplier had to invest significant resources to resolve the issue.
A Gemba walk could have helped prevent this problem. The broken pin and the resulting crooked tabs would have been identified by asking the operator whether anything had changed recently. This direct feedback could have prompted corrective action, ensuring a consistent process and avoiding costly errors.
Gemba Walk Examples: Production boards
Every morning at 9 am, the most senior leader in a facility, typically a Vice President, embarks on a Gemba Walk accompanied by a diverse group of key personnel, including the National Sales Director, Manufacturing Manager, Production Managers, Shipping Manager, Production Planner, Purchasing Manager, HR Manager, and the in-house Lean team. The walk involves stopping at designated "production boards," where discussions focus on current operational issues. If any conversation extends beyond three minutes, a specific individual is assigned to organize a follow-up meeting or initiate a review to address the matter effectively.
This practice fosters direct communication across the organization, as operators at each station actively participate in the discussions, ensuring that every company layer stays informed and engaged. Employees gain insight into organizational priorities and challenges while witnessing senior management's commitment to resolving problems. The daily interaction improves the flow of information and demonstrates the leadership's genuine interest in their teams and their work, enhancing morale and creating a stronger connection between staff and management. (4)
Gemba Walk Examples: Poka Yoke fails
In a manufacturing plant, a pin dispensing machine was installed as a poka yoke to ensure the assembly process used precisely four pins. The design aimed to prevent missing pins by dispensing them into a tray, allowing the operator to use precisely what was needed for each task. However, the system had a critical flaw: the tray beneath the dispenser was too flat, causing pins to slide off onto the floor. This forced the operator to press the button again to dispense more pins, leaving some pins in the tray and others scattered on the floor, ultimately defeating the purpose of the poka yoke.
A Gemba walk focusing on 5S principles could have highlighted this issue by drawing attention to loose components on the floor of the workstation. Through observation and dialogue, the operator suggested a simple yet effective solution: replacing the flat tray with a deeper dish. This adjustment would securely hold the screws, allowing the dispensing machine to function as intended and eliminating unnecessary waste and inefficiency. (5)
FAQ
What is the main purpose of a Gemba walk?
The primary purpose of a Gemba walk is to observe work processes directly where they happen, engage with employees, and gain insights into operations. It allows leaders to understand what is working, identify areas for improvement, and foster open communication between management and staff. Gemba walks aim to promote problem-solving and continuous improvement while building stronger relationships within the organization.
How do Gemba walks benefit employees?
Gemba walks benefit employees by providing them with an opportunity to share their insights, challenges, and suggestions directly with leadership. This interaction demonstrates that management values their input and efforts, which can boost morale and engagement. Employees also gain clarity on organizational goals and feel more connected to the problem-solving process when their perspectives are actively considered.
What should leaders focus on during a Gemba walk?
During a Gemba walk, leaders should focus on observing work processes, listening to employees, and asking questions to understand challenges and workflows. The goal is not to criticize or micromanage but to gather information and collaborate on solutions. Leaders should also look for inefficiencies, waste, or safety concerns and involve employees in identifying opportunities for improvement.
Takeaway
The primary goal of Gemba walks is to observe, listen, learn, and offer support. This method allows leaders to immerse themselves in the daily operations on the floor, gaining a clear understanding of what is functioning effectively and what is not. By engaging directly with workers, leaders can better understand their approaches to problem-solving and continuous improvement in their routines.
Beyond observation, Gemba walks serve several critical purposes. They help identify issues and provide insights into how these can be addressed. Leaders can pinpoint and work to eliminate waste, such as redundancies, bottlenecks, non-value-added steps, or safety hazards while uncovering opportunities for continuous improvement. Additionally, these walks facilitate meaningful discussions with employees about goals and objectives, fostering collaboration. By building stable and trusting relationships with those who perform the work and create value, leaders strengthen the foundation for organizational growth and innovation, one essential ingredient of the future factory.
Delve deeper into one of our core topics: Real time location systems
Glossary
Poka Yoke - Poka-yoke (ポカヨケ, [poka joke]) is a Japanese term meaning "mistake-proofing" or "error prevention." It is sometimes described as a forcing function or a behavior-shaping constraint.
Poka-yoke refers to any mechanism within a process designed to help equipment operators prevent errors, correct them, or highlight potential issues as they arise. This approach minimizes defects and human errors during production. The concept was formalized by Shigeo Shingo and became a key component of the Toyota Production System. (6)
Sources:
(1) Fujimoto, T. (1999): The evolution of a manufacturing system at Toyota. Oxford University Press
(2) Monden, Y. (2010): Toyota Production System: An integrated approach to just-in-time. Productivity Press
(3) Suzaki, K. (1987): New Manufacturing Challenge: Techniques for Continuous Improvement. Free Press
(4) https://www.leanblog.org/2007/08/gemba-walk-example/
(5) https://www.ease.io/blog/gemba-walk-examples/
(6) https://en.wikipedia.org/wiki/Poka-yoke
(7) https://www.isixsigma.com/press-releases/manufacturing-survey-finds-widespread-use-lean-six-sigma-5s-kaizen/
(8) https://supplychainminded.com/most-companies-are-using-lean-but-not-always-so-well/
