What is SMED (Single-Minute Exchange of Die)?

What is SMED (Single-Minute Exchange of Die)

A company’s efficiency is one of the best indicators of its viability and chances of financial success. Broadly speaking, every business’ ultimate goal is to create as much output (products or services) at as little resource cost (money, time, materials) as possible.

There have been many strategies developed to try and help achieve that goal by streamlining processes and simplifying tasks. But few are as well known and loved as the Single-Minute Exchange of Die (SMED) approach.

In this article, we’ll discuss the what, who, why, when, and how of SMED. More specifically:

  • What is SMED?
  • Why is SMED so popular?
  • When should you consider SMED?
  • How can you use SMED for your business?

What is SMED?

As mentioned above, the abbreviation stands for “Single-Minute Exchange of Die”. In the context of this phrase, “die” means a specialized tool for manufacturing a specific product. Factories that want to use a single assembly line for producing multiple items often need to change dies, which is a hard and time-consuming process.

Shigeo Shingo, a Japanese engineer working at Toyota, noticed the issue and wanted to do something about it. In 1969, he came up with a set of processes that could shorten the time needed to change dies to under 10 minutes – in other words, a single digit. The practice spread overseas and became known as Single-Minute Exchange of Die, or SMED for short.

However, despite the language used, SMED did not stay confined to the manufacturing sphere for long. Nowadays, companies in the service industries (health, hospitality, etc.) also use SMED to boost their output and performance.

The 3 basic principles of SMED consist of:

  • Dividing processes into “internal” and “external” elements
    By Shingo’s definition, internal elements are processes that can only be completed while the machines are stopped. External elements on the other hand are steps that can be fulfilled even while production is running.
  • Converting internal elements into external ones
    This can be done either via change in procedure or alterations made to the machinery.
  • Streamlining remaining internal elements
    Some actions can’t be transformed into external elements, and can only ever be completed during machine downtime. These must be optimized to achieve the best possible results.

Why is SMED so popular?

One of the reasons why SMED became so popular is that Shingo was supposedly able to use it to boost companies’ efficiency on average by 94%. Combined with its other benefits, it’s clear why so many businesses sought to replicate Shingo’s success.
SMED’s benefits include:

  • lower manufacturing costs
  • higher efficiency
  • smaller lot sizes
  • lower inventory levels
  • improved responsiveness to customer demands
  • smoother operation startups
  • and more

However, despite all of these advantages, SMED does not fit every company. You should carefully consider if it is right for you, especially if you’re a business operating outside the realms of manufacturing.

Explanation of what is SMED

When should you consider SMED?

In spite of its many benefits, SMED is not a magical wand. It has its limitations, which can make or break it for your company’s use-case. So, before you settle on onboarding it into your operations, you should consider the following:

  • Do you have processes SMED can improve?
    As mentioned, SMED works best for manufacturing. It’s primarily focused on large assets, and recurring or one-time work orders.
  • Do you have the means to keep to the standardized processes?
    SMED only works efficiently when all work requirements are fully and perfectly completed. This makes SMED particularly difficult to achieve due to the human element. Negligence, mistakes, and unfamiliarity with the processes all affect the outcomes you’ll see.

If you answered “yes” to both these questions, then you can start looking at incorporating SMED into your company activities.

How can you use SMED for your business?

Once you’re settled on improving your work processes with SMED, you’ll need to create your strategy. This can be broken down into 5 distinct steps:

How is possible to use SMED infographic

  1. Identify the process(es) that need SMED the most
    Not all processes are equal. If you want to make noticeable improvements to your operations, you’ll need to target processes where SMED can realistically make a change. However, a word of warning – do not set your goals too high to begin with.
    If one of your processes takes on average 10 hours, it’s not realistic to cut it down to 9 minutes. Temper your expectations and strive for the best.[Text Wrapping Break]
  2. Separate internal and external activities
    As mentioned before, SMED divides parts of your process into internal and external activities. Write down everything that needs to happen for your process to be completed. Then, start looking for activities your workers can achieve even while the machinery is running.
  3. Convert internal activities into external ones
    Next, consider the internal activities you identified in the previous step. Can any of them be transformed into external ones? Keep in mind every action you convert will significantly improve your efficiency.
  4. Create a standardized process
    Once there are no more improvements to be made, write down everything you’ve learned. Create a guide on how to complete this new and improved process and couch your employees on it.
  5. Train your team and continue improving
    Continue working with your employees to erase any mistakes, unnecessary delays, and more. Review your standardized process periodically and see if you can’t make any further improvements.


SMED is an effective and historically significant way of improving your company’s efficiency. However, incorporating it into your operations can be sometimes difficult. So, before you jump head first into this endeavour, assess the state of your equipment with Resco’s Machine Maintenance Checklist. You may find that the issue you’re experiencing stems from a malfunction, rather than a lack of efficiency.