SMED: The Lean Technique That Can Transform Manufacturing Efficiency

In today's competitive manufacturing environment, companies are constantly searching for ways to increase flexibility, reduce costs, and respond more quickly to customer demand. One of the most powerful Lean Manufacturing techniques for achieving these goals is SMED, which stands for Single-Minute Exchange of Dies.

Despite its name, SMED is not limited to changing dies in a press machine. It is a systematic methodology for reducing setup or changeover times in any manufacturing process. Whether switching between product models, adjusting machine settings, or preparing production lines, SMED helps organizations minimize downtime and maximize productivity.

What is SMED?

SMED was developed in the 1950s and 1960s by Japanese industrial engineer Shigeo Shingo as part of the Toyota Production System. The primary objective is to reduce setup times to less than ten minutes or at least make them dramatically shorter than before.

Long changeovers force manufacturers to produce large batches in order to justify the downtime. While this may seem efficient, it often results in excessive inventory, longer lead times, and reduced flexibility. SMED addresses this challenge by making changeovers so quick that smaller production batches become economically viable.

The SMED methodology follows three main steps:

1. Separate Internal and External Activities

Internal activities can only be performed while the machine is stopped, whereas external activities can be completed while the machine is still running. The first step is to identify each activity and determine whether it truly requires production to stop.

2. Convert Internal Activities into External Ones

Many tasks traditionally performed during downtime can actually be completed beforehand. Preparing tools, preheating equipment, organizing materials, or verifying settings before shutdown significantly reduces idle time.

3. Streamline Remaining Internal Activities

For the tasks that must occur during the changeover, the goal is to simplify and standardize every step. Quick-release fasteners, standardized tooling, parallel operations, and visual work instructions all contribute to faster and more consistent setups.

Reducing setup times delivers benefits that extend far beyond the production floor. Faster changeovers enable manufacturers to produce smaller batches without sacrificing efficiency, leading to lower inventory levels and improved responsiveness to customer demand.

Let´s see a simple example to illustrate this technique.

Imagine a packaging line that requires 90 minutes to switch from one product size to another. By analyzing the setup process, the team discovers that many tools are collected only after the machine stops, settings are adjusted manually, and operators perform tasks sequentially.

After applying SMED principles, tools are prepared in advance, machine settings are standardized, and two operators perform different tasks simultaneously. The result? The changeover time drops from 90 minutes to just 15 minutes. The company can now produce smaller batches, reduce inventory, and respond more quickly to changing customer orders.

SMED is more than a technique for speeding up machine setups, it is a mindset focused on eliminating waste and improving operational agility.

In a world where customer expectations continue to evolve and product lifecycles become shorter, the ability to change production quickly is a significant competitive advantage.

Whether you manage a large manufacturing facility or a small production line, implementing SMED can unlock hidden capacity, improve efficiency, and support a more responsive and resilient supply chain. Sometimes, the biggest improvements come not from working harder, but from making every minute count.

Lean 8 wastes

  

Before we dive into the eight types of wastes, it is important to understand what waste is.

Waste is any action or step in a process that does not add value to the customer.

Originally seven wastes (Muda) were identified, and a methodology was developed by Toyota, as part of the Toyota Production System (TPS).

The seven wastes were; Transportation, Inventory, Motion, Waiting, Overproduction, Overprocessing and Defects. They are often referred to by the acronym ‘TIMWOOD’.

The 8th waste of non-utilized talent or ‘Skills’ of workers was later introduced in the 1990s when the Toyota Production System was adopted in the Western world. As a result, the 8 wastes are commonly referred to as ‘TIMWOODS’.

We can now deep dive into each of these eight wastes and understand how we can reduce or eliminate them as part of a leaner and more efficient operations.

Kaizen: All you need to know

 

Kaizen is a business philosophy that focuses on continuous improvement across the entire organization. The pursue of the kaizen model is to help companies focus on gradually and consistently increasing efficiency and reducing waste within processes. That doesn't mean alterations happen slowly. The kaizen process simply recognizes that small changes now can have huge impacts in the future.

To achieve all this, kaizen encourages input from any employee, from the factory floor to the most senior management.

The kaizen method became popular in Japan, at manufacturers like Toyota. Kaizen can broadly be translated as means continuous improvement in Japanese.

There are five fundamental Kaizen principles that are embedded in every tool and behaviour:

1. Know your customer

2. Let it Flow

3. Go to Gemba

4. Empower People

5. Be Transparent

Traditionally, kaizen has been known for its events, usually a three- to five-day team workshop in which employees, managers, and sometimes C-suite executives make an actionable plan to improve an existing process. Kaizen events often follow Gemba Walks or the discovery of an inefficiency. We have spoken about Gemba Walks in the past, these are visits to workplaces where management teams can witness processes, talk to employees, gather insights, and identify any issues. You can read more about Gemba Walks in here.

After you’ve identified problems or bottlenecks in a process, start making small, continuous improvements. During the kaizen event, team members collaborate and think of solutions. The ideal outcome of these events is an actionable plan that is ready for implementation.

Kaizen events can take many forms to best serve their business application.

1. Focused-improvement kaizen. A focused-improvement event is a kaizen event centred on a single, known issue. Prioritize your most important losses and develop solutions to eliminate them.

2. Waste kaizen. This type of event focuses on eliminating waste in your processes, as opposed to improving systems that are currently working.

3. Error-proofing kaizen. Use this type of event to reduce human error by improving processes. This could be as simple as standardizing checklists, automating parts of a system or using Poka Yoke which we talked about here.

4. Lead-time kaizen. This kind of event is suitable when you realize one of your processes is taking too long. The event aims to reduce the amount of time it takes to complete a process, like the time from processing an order to the customer receiving their goods.

How to run a Kaizen event:

There is not a unique way to conduct a kaizen event but the plan-do-check-act (PDCA) framework is common and often recommended method.

1. Plan

The Gemba Walk, mapping your value stream, and identifying the problems in your processes are part of the planning stage in a PDCA cycle. Follow these steps to get started.

• Speak to employees. They’re the people who know the daily process better than anyone, so find out what problems or issues they're aware of.
• Define and analyse the problem. When you’ve decided which issue to tackle, break it down and find the bottleneck in the process.
• Establish the metrics you’ll use to measure success. Without this data it’s impossible to analyse the results after you’ve tested the solution.
• Decide on a goal. You should have one goal that is achievable within the event time frame.
• Work as a team to find solutions to the problem. There should be no limits on the kind of solutions encouraged. Allow employees to use their creativity. Choose one with potential to start with.

2. Do

Run a small-scale test of your chosen solution. Make sure every team member involved is aware of the change and let it run long enough to gather meaningful data and feedback.

3. Check

Collect data from your test and assess its success.

4. Act or adjust

If the test was a success, scale, implement your improved process company-wide or as a permanent update. However, if you found issues, or if the solution didn’t work, refine the process, and run further tests or choose a different solution and try again.

This should be a cyclical process. The kaizen event might be a one-time event but the process of improving never stops. To keep the continuous loop going, repeat the cycle. Find more processes to improve or try out other solutions.

Hoshin Kanri: translating strategic plans into actionable items

Many companies struggle with translating strategic plans into actionable items on a daily process, luckily, among the most powerful tools in the Lean arsenal for effective strategic management we can find Hoshin Kanri.

Similar Jidoka or Just in Time, Hoshin Kanri has its roots in the Toyota Production System and as a tool, it can be very helpful, when implemented properly, in bridging the gap between strategy and execution.

Hoshin Kanri has a Matrix shape with four quadrants each devoted to a specific task.

1-     Set the strategic vision & goals (3-5 year breakthrough objectives):

 

The long-term goals is the starting point In Hoshin Kanri, normally in the frame between 3 and 5 years.

 

List them at the bottom quadrant of the matrix template and have in mind that every initiative will have many smaller tasks that will need to process before achieving the goal.

 

2-     Define key mid-term objectives (annual objectives)

After your long-term goals are all set, prepare the most important objectives that you aim to achieve in a shorter time frame and put them in the left quadrant of the Hoshin matrix.

 

3-     Set short-term actions and metrics (improvement priorities)

 

You will need to fill the top quadrant with the most important activities that need to be completed to achieve the short-term goals, this is basically the to-do list for the upcoming months.

 

4-     Agree on key performance indicators (targets to improve)

Agree on the most crucial metrics that need to be improved and list them on the diagram.

 

Following this line of thought, right next to the key metrics, you need to list the key stakeholders responsible for leading the completion of the activities in the matrix's top quadrant.

 

Finally, you should complete the picture by specifying the dependencies between every listing in your matrix.

Logistionary: Kaizen

Kaizen is a Japanese word that means “change ofr better” but it´s also a philosophy that refere to continuously improve; instead of encouraging large, radical changes to achieve desired goals, Kaizen philosophy recommends that organizations introduce small improvements, preferably ones that could be implemented on the same day.

In Supply Chain Kaizen is an on going process and its purpose goes beyond simple productivity improvement. It is also a process that, when done correctly, humanizes the workplace and teaches people how to eliminate waste.

While Kaizen usually delivers small improvements, the culture of continual small improvements and standardization yields large results in terms of overall improvement in productivity.

The following video, although in Spanish compliments the abobe information in an easier and approachable way!

The Dabbawalas

This post will be devoted to explore one of the many sets of tools for process improvement, six sigma. 

But don’t worry about a tedious post with lots of theory and boring stuff. Just a very quick overview to have some context before travelling to India to discover one of the very few businesses that have been able to comply with the six sigma principles!

Introduced by Motorola in 1986, today, it is used in many industrial sectors. Six sigma seek to improve quality by identifying and removing causes of defects or errors and minimizing variability in manufacturing processes

A Six sigma process is one in which 99, 99966% of the products manufactured are free of defects, that is an error rate of 3.4 per million units manufactured, quite an ambitious challenge!

Now we know what six sigma is, allow me to take you to India, where there is a business that has achieved 99.9966% of effectiveness, but before that, I want you to stop thinking about bleeding edge technology, Harvard master minds or bright recently created companies, because most of the people that have achieved what today is the goal of the most cutting edge companies can barely read and most of them probably never have had a computer anywhere around their working facilities.

If you think this is not possible, let me introduce you to the Dabbawalas. A Dabbawala is a person in India, generally in Mumbai, who collects hot food in lunch boxes from the residences of workers in the late morning, delivers the lunches to the workplace utilizing various modes of transport, predominantly bicycles and the railway trains, and returns the empty boxes back to the customer's residence that afternoon.

There are approximately 5000 Dabbawalas in Mumbai that deliver around 200.000 tiffin boxes every day.

A typical day for a Dabbawala starts when the cylindrical metal tiffin boxes are collected from homes and taken to the nearest railway station where they are loaded onto crates and transported by train to downtown Mumbai where the boxed will be loaded onto hand carts or carried on long trays balanced on top of heads. 

On average one tiffin box will change hands four times in its journey from a home kitchen to a hungry office worker. So far, so simple, however, the majority of the Dabbawalas are illiterate and the sorting is done mostly by a system of color coding that has hardly changed since the first tiffin was delivered in 1890.

Lunch boxes are usually marked in several ways:

      - Abbreviations for collection points.

      - Colour code for starting station.

      - Number for destination station.

      - Markings for handling Dabbawala at destination, building and floor.

And here it comes the impressive fact; it is frequently claimed that Dabbawalasmake less than one mistake in every six million deliveries, equivalent of Six Sigma or better, proving to be more efficient than the most renewed companies in the world.

If you want to know more about the Dabbawalas, I would recommend to watch the next video, an image is worth more than a thousand words!