How SMED – Single Minute Exchange of Dies – Reduces Changeovers

The Lean East website has a page in our “About” section titled What is Lean? in which we introduce some basic Lean concepts, tools, and principles we use to help organizations improve customer value and grow profits. One of the tools we haven’t posted about is the Single Minute Exchange of Dies (SMED) focus on changeover reduction. While the Single Minute Exchange of Dies was developed in manufacturing, we are going to explain how SMED can help in service organizations and personal improvement as well.

The Origin of SMED

Single Minute Exchange of Die (SMED) is a core concept in Lean Manufacturing, focused on drastically reducing the time it takes to change over equipment from producing one product to another. The driving force behind SMED was Shigeo Shingo, a Japanese industrial engineer and consultant who worked with Toyota in the late 1950s and early 1960s.

Shingo participated in Quick Die Change (QDC) workshops at Toyota and used a structured approach to analyzing and optimizing changeover processes. He famously coined the term “Single Minute Exchange of Dies,” where “single minute” refers to a single-digit number of minutes (i.e., less than 10 minutes), not necessarily one minute exactly. Shingo and Toyota often reduced exchange time by 95%, allowing for smaller production lots, reduced inventory, increased flexibility, and supporting Just-in-Time in the Toyota Production System.

Why is Reducing Changeover Time Important?

It is rare today to spend all of your time on a single task. Most of us run around jumping from one priority to the next. Frequent task switching is sub-optimal, with some estimates suggesting that task switching can reduce productivity by as much as 40%.

Here are a few areas outside of a manufacturing process that can suffer from task switching:

1. Healthcare clinic – moving between patients or turning over rooms between patients
2. Restaurant kitchen – switching back-and-forth between meals being cooked
3. Software development process – switching between coding, testing, and releasing steps
4. Hair salon – moving between clients while receiving payment
5. On-line customer support – answering a new request while waiting for another client to provide answers to questions
6. Your brain – maintaining focus and not forgetting steps when “multi-tasking”

The Toyota Method for Reducing Changeover Time

The concept of SMED can be useful in helping us changeover between tasks. Shingo’s SMED methods at Toyota involved systematically identifying and separating “external” setup activities that can be done while the process is running and “internal” activities that can only be done when the process is stopped.

Once internal and external activities were separated, Shingo then worked hard to:

1. Standardize the process and convert the internal activities to external activities wherever possible
2. Streamline and remove the waste from the external (prework) activities
3. Remove the waste from any remaining internal activities. For example, Shingo converted hardware requiring tools to simple hand-operated clamps.

Using SMED in your Work Process

Here are a few examples that use SMED thinking to become more effective in some of the service processes we shared earlier. Each service process has example solutions using Shingo’s three-step process above.

1. Healthcare clinic – moving between patients or turning over rooms between patients
   • Pre-assembling patient kits or trays, preparing patient charts/electronic records ahead of time, having examination tools organized and charged in a ready cart, pre-filling prescription orders
   • Color-coded supply carts, quick-disinfecting wipes/solutions
   • Using pre-packaged sterile kits, optimized anesthesia, medical history checked using AI
2. Restaurant kitchen – switching back-and-forth between meals being cooked
   • Pre-chopping vegetables for the dinner menu during lunch downtime, preparing sauces, pre-heating ovens, staging all necessary dinner ingredients at the workstations
   • Adding chopping tools, creating meal kits
   • Quick-release connections for kitchen equipment, standardized “mise en place” (everything in its place) systems, specialized cleaning tools
3. Hair salon – moving between clients while receiving payment
   • Pre-mixing hair color for the next client while the current client’s color is processing, sweeping hair while the client pays
   • Clients pre-pay on-line in advance, organizing and auto-sterilizing tools, preparing the next client’s cape and towels
   • Designated cleaning stations with quick access to sanitizers, mobile tool carts, efficient waste disposal systems right at the chair, or a “next client ready” signal system

Using SMED for Personal Productivity

Here are a few ideas on how you can use SMED thinking to become more effective in your own day-to-day life.

1.Switching Between Projects/Tasks:

• Prepare task-specific folders/tabs in your browser
• Have a “next action” list for each project
• Create “templates” for recurring tasks
• Dedicate specific blocks of time to “email answering,” “report writing,” “meeting preparation,” or “phone calls.”

2.Morning Routine (Getting Ready for Work/School):

• Create a standardized morning routine
• Use smart home devices to automate tasks (lights, thermostat, etc.)
• Have a dedicated place for everything (keys, wallet, purse, bills, etc.)
• Lay out your clothes for the next day the night before
• Pack your lunch the night before
• Pre-set the coffee maker on a timer

3.Meal Preparation:

• Create a meal plan for the week then a shopping list
• Plan meals to optimize ingredient use (e.g. two different sauces that both go with the same pasta)
• Make several larger meals that can be reheated during the week
• Cook these meals back-to-back while the oven is already warm
• Use meal prep containers
• Have a quick-access spice rack
• Use only easy-to-clean kitchen tools

4.Packing your bags:

• Have a pre-made packing checklist for trips
• Store travel-sized toiletries permanently packed in the quart-sized bag
• Have a dedicated drawer or bin for travel essentials (adaptors, chargers)
• Use packing cubes to organize items
• Roll clothes to save space
• Setup bags for separate purposes (work, running, gym, overnight trip, shopping, etc.)

Summary

We hope you found this short post on how SMED – Single Minute Exchange of Dies –methods can reduce setup times helpful! Please leave your comments and questions below.