Tag: SMED

The Final Stages of our Quick Changeover Implementation

SMED Stages 5 to 7

I will deal with the final stages of SMED in one single post as these stages are fairly simple and related. We have already by now significantly reduced our Setup, hopefully already down to single minutes. The aim of SMED or Single Minute Exchange of Die is to get the changeover down to less than 10 minute.

SMED Stage 5;

Improve External Activities

You will probably be at a stage now where the activities that are performed while the process is still running take longer than the actual quick setup process that you now have. This should be worked on using the same ideas that you have already used for your internal activities to ensure that you reduce the time that is spent on these external activities;

• Look at 5S principles on your external setups
• Look at who is performing the activities
• Look at where the activities are being done
• Look at easier ways to actually perform the activity

Once you have reduced your external activities once again ensure that your process if fully documented to ensure that everyone follows best practice at all times. You do not want to have differences between different operators or shifts.

Use 5S principles to improve your external changeover time

SMED Stage 6

Automate Change Over

Automation is rarely a cheap option which is why this is one of the final steps of your SMED implementation. In most cases you will be able to reduce a setup to less than 10 minutes without the use of any form of automation.

Before embarking on any form of automation you should very carefully consider the cost benefits of what you will do as well as the final step of our quick change over program which is to actually eliminate the changeover completely. If the cost benefits are not going to justify using automation you should revisit the previous steps of your Single Minute Exchange of Die program to see if you can achieve any additional changes.

The other reason for Automation is of course safety is you are handling heavy or hazardous materials in which case automation is a very valid way of moving forward.

I have rarely seen the need for a changeover to be automated, the few times that it has been automated it has come with automated loading and unloading of components so people have actually been freed from the process to conduct other work within the process.

SMED Stage 7

Eliminate The Changeover

The ultimate changeover reduction is of course to eliminate the entire setup. If there is no need for a changeover then you will waste no time. This can be achieved through the following simple ways;

Have dedicated machines; often it is cheaper to have many smaller dedicated machines than one all singing all dancing super machine that does everything.

Design Modifications; remove the need for multiple components through the design process

Modify tooling to produce multiple parts; consider an “airfix” style injection molding tool that produces a whole set of components rather than multiple sets of one component.

Like automation eliminating the setup can be an expensive and often time consuming option so it is something that will require a cost benefit analysis.

Feedback your SMED Learning Into Your Design Process

It is always best to try and include members of your design teams into your SMED implementations so that they fully understand the results of some of their choices and are able to feedback what they learn into future designs. Far better to be able to start a new product with no changeovers or changeovers that are already in single minutes.

Help With Your SMED Implementation

If you are having any problems with your quick changeover process feel free to contact us here for help and advice in ensuring that you achieve your setup goals. If you feel that any of the information here is unclear or you would like to add anything then feel free to use the contact page to get in touch.

Improving the Internal Setup Activities

The Fourth Stage of SMED

In the previous stages of our SMED implementation we have identified and separated the internal and external activities of our changeover, internal activities being those that have to be done while the machine is shut down and external being those that can be safely completed while the machine is still running. We have then gone through the internal setup activities to convert them to external activities. At this point we have probably managed to save around 75% of our setup time.

Why do we need to improve the internal setup time

Having managed to make significant improvements for our quick changeover we now need to look at improving those activities that must be performed while the process is actually idle. This is the point that most engineers want to jump to straight from the start; but if they did they would lose out on all of the savings that we have already made.
This stage will see us look at and begin to improve those activities that have to be undertaken while the machine is stopped, this will be the controlling factor in reducing our time further. This means looking at every stage of what we do and asking ourselves why we are doing it and if we can do it better.

Reduce Setup by reducing time spent on the internal setup

How do we improve our internal changeover activities?

We already have our breakdown of the process from our previous steps; we now need to look at each individual step and ask ourselves firstly why are we doing it? Maybe we can skip the step or it should be part of our external setup and we have overlooked it within the previous stage.
If we have to do it as part of the internal setup we should ask ourselves who, where and when it needs to be done before we look at how.

• Is this the right stage of the setup to do it?
  • Can it be done easier or quicker earlier or later in the process?
• Is this person the right one to undertake the activity?
  • Is there scope for more than one person to conduct the changeover?
• Is it being done in the right place?
  • Can it be done quicker from elsewhere?
• Then we need to ask ourselves are we doing it in the right way?
  • Is there a quicker more efficient way to do this?

Examples of SMED improvements

One of the commonest things that delays all setups is the use of bolts and screws to fix jigs and fixtures, as Shigeo Shingo once said; “only the last turn of the bolt tightens, the rest is motion (waste).” How often have you seen a setter struggling with an spanner to tighten a bold for a minute or more and then repeating it a dozen more times.
To eliminate the waste of tightening bolts there are a number of options that we can implement; these can range from boltless clamping using toggle clamps or offset cam levers through to pear shaped holes that can be slid over bolts and then only need a single turn to tighten.
The pictures below shows several options that you could use;

Quick release clamping using a single turn of a bolt.

Pear Shaped Holes Enable Quick Release

Many setups also require the use of measurement or careful adjustment to set things such as guides or to position tools just right; these should instead be done through physical pinned locations or by using setting jigs or spacers so that there is no need to use measurements.

Standardized Clamping Heights to Reduce Setup Time

Standardize Your Internal Setup Activities

Machine and process settings should also be recorded so that you have a set baseline from which to start the process each time rather than relying on the memory of the setters. You will often find that different operators or setters will have different settings that they use and these should be standardized. Again update your operating and changeover instructions at the end of this stage to ensure that everyone understands what they should do and that the time savings you have gained are maintained.

Rinse and Repeat

We are aiming here for a quick changeover that is less than 10 minutes in length, if we have not yet achieved this then before we look at the later stages we should repeat this process until the team feels that they have exhausted all possible solutions. If necessary bring in new team members to provide a fresh set of eyes on your setup process.

Improve External Activities

We should now have improved the internal setup activities significantly compared to where we were when we first started our SMED implementation. However we now need to go and take another look at our external setup activities as we will probably find now that they are more time consuming than the rest of the setup. You will find the next stage of our single Minute Exchange of Die implementation by clicking the link to our final SMED Stages to improve external setup, implement automation and eliminate changeover completely.

Converting Internal Changeover Activities into External Changeover Activities

Third Stage of our SMED Implementation

If you have got this far with your SMED implementation then you will have probably shaved at least 50% off of your changeover and will be eager to achieve more. In the first stage we separated our internal and external changeover activities allowing us to ensure that all of the external activities were already completed prior to us actually stopping the process. This included things as simple as finding tooling and having everything to hand before we actually started the quick changeover, things that many would say should be common sense but still failed to implement before.

The second stage saw us standardize external setup elements ensuring that not only do we have a quicker changeover but that it is done repeatably and also preventing the creep back to where we were before; something that always tends to occur if we don’t document our new ways of working.

The next step is to look at all of the internal setup activities and consider how we can convert them into external activities allowing us to further reduce the actual down time of the process while we setup.

Why do we need to convert internal setup activities into external?

(Why Improve Something if you Don’t Need to do it!)

The Internal activities have to be done while the process is at a standstill, so obviously we are seeking to minimize this time. The engineers amongst you will be keen at this point to jump in and to try to make every stage of our changeover easier and quicker but you need to ask yourself first does this step even need to be done as an internal step? Is there a way that we can convert this step into an external activity that can be done while the process is still running? We need to see if we can remove some of these internal changeover steps rather than just trying to make them quicker. Often by the time we get to the end of this third stage it is not unusual to have eliminated 75% or more of the original setup time.

SMED Stage 3, Convert Internal to External

What sort of activities can be converted?

The following is a list of common activities that could be modified in some way so that they can be done while the process is still running;

• Preset cutters within a tool using fixtures so that they are ready to use
• Use intermediate jigs allowing dies and fixtures to be mounted and adjusted prior to fitting
• Preheating of Dies /materials (Formula one tires are heated to race temperature before fitting)
• Additional set of changeover parts available pre-cleaned rather than having to clean and re-use what is currently in use.

If you find something that is not on the list then do it and let us know.

Standardize your new external activities

Once you have your new external activities ensure that you add them to your check sheets and standardized ways of working that you produced in the second stage of our SMED implementation. Far too often people get carried away with the success of making so many improvements that they forget to document everything and six months later things have drifted right back to where you started.

Create Simple Instructions for your Changeovers

Improving Internal Changeover Time

The next stage of SMED is to look at improving the internal changeover activities themselves and to see what can be improved to further reduce the time for our quick changeover. So our next stage is to improve internal setup activities for SMED.

 Standardizing the External Activities

The Second Stage of SMED

In the first stage of our quick changeover process we used videos and flow charts to identify all of those activities within our setup that can be conducted as external activities; that is they can be done while the process is still running. So these are things such as fetching tooling and instructions. This enables us to have all of these activities prepared before we stop the process and begin the main part of our quick changeover. By this point we will often have put everything in place to save at least 50% of the downtime caused by our changeover.

In this second stage of our SMED implementation we will look at organizing and standardizing these external activities to ensure that they are done quickly and efficiently. Failure to do this will result in us still searching for tooling and other items when the machines are at a standstill giving us a longer than necessary changeover.

Standardizing External Activities can reduce the amount of time spent on them.

What do we mean by standardize this process?

I am sure that within the videos that you watched of the setup that there were times when the people doing the setting had to wander off to find something or were searching for something in a draw or some other wasteful and time consuming activity. If you videoed more than one shift or different setups performed by different people I am sure that you also saw things done in a different order or even using completely different methods.
The idea of this step of the process is to get organized and to define exactly how everything should be done so as to eliminate some of the waste and to ensure that things are done in the best (safest, efficient) way.

Lean 5S and SMED

Getting Organized

Another Lean tool known as 5S is very helpful at this stage. 5S is a technique that is used to organize a work space so that everything is there and in the right place to be used efficiently. It is also used to produce standardized processes and to create a highly visual workplace which makes elimination of problems very easy.
You can read a step by step guide for 5S through this link; 5S Guide

Using the analysis from the first stage we can produce a simple checklist for all of the information, tools and materials that should be available, this should cover everything such as;

• Documentation
  • Production orders
  • Standard Operating Instructions
  • Engineering Drawings
• Production Dies, Jigs and Fixtures
  • List of what is required
  • Check all clean and in working order
  • All components and fixings (list them all)

• Tools
  • List all tools (screwdrivers, Allen keys, etc)
  • Check all clean and working order

• Measurement Inspection Tools
  • List all (calipers, scales, measures etc.)
  • Inspection instructions
  • Check all clean and working

• Materials
  • List all (Type, size, grade etc.)
  • Right quality, quantity and right location

Standardize the External Activities using checklists and improving layout

For those items that are used on a regular basis (often called “runners”) we can find locations where or very close to where they are actually used so that they are at hand when we need them. The use of tooling shadows or clearly labeled shelves can make it very obvious if these items are missing so they can be found long before we start the changeover.
Part specific tools and equipment can be gathered on a trolley prepared before we start the actual changeover. Again a well labeled trolley with tooling shadows and the like can ensure that everything that we need is there before we start.

Organize using 5S principles

Documenting the external activities

Good organization itself can ensure that your external activities are conducted properly and that all tools and equipment are gathered and in place. The checklist however can be utilized as an extra check to confirm that all is where it should be before the main part of the changeover begins. Using 5S principles however where everything has a place and everything should be in that place will help to ensure that anything missing stands out clearly.
For actual processes that need to be conducted such as cleaning tooling or physically setting up more complicated equipment you should create specific work instructions detailing out the best methods for conducting it so that they are done in the most efficient ways possible to prevent problems during the setup itself. Using a digital camera and simple word processing packages it very easy to design and print easy to follow instructions, they do not need to be overly complicated.

Create Simple Instructions for your Changeovers

This stage of SMED may not in itself appear to shave any time off the changeover, however by having everything organized and documented you will avoid the problems that would otherwise occur. Without clear instructions, organization and a clear work space you ca guarantee you would regularly hit delays within your setups.

The Next Stage of SMED

The next step for our quick changeover is converting internal activities into external activities. This is where we take another look at the internal setup activities and try to find ways to do them while the process is still running allowing us to further reduce the machine downtime and providing us with a much quicker changeover.

Separate Internal and External Setup Activities

The First Stage of SMED

If Someone told you that you could easily reduce your changeover times by as much as 50% without spending any money or even having to work very hard you would probably tell them that they are talking rubbish. But that is what most companies achieve just through this initial analysis of the setup when implementing SMED. We often spend well over half of our changeover doing things that we could have had prepared before hand; so why do we do it – because we have always done it that way!

What are Internal and External Setup Activities?

When you conduct a setup on a process or a machine there are some parts of your setup that can be conducted while the machine is running and others that require that the equipment is stopped. Internal setup activities are those that require the process to be at a standstill before you can conduct them safely while external activities can be done while the process is still running.

Examples of External Setup activities

• Fetching new tooling
• Returning the old tooling
• Finding tools for the setup
• Finding correct paperwork
• Fetching raw materials

Examples of Internal Setup activities

• Removal of guarding from equipment
• Removal of the old tool
• Placing the new tool
• Connecting services such as air to new tool
• Clearing hoppers / material feeders

The Aim of separating external and Internal setup activities

Because all of your external activities can be done whilst the process is still running you can ensure that everything is done before you get to the point of the last part of the current batch. It is common that tools, equipment, paperwork and materials for instance are collected while the machine is already inactive. If everything is already prepared before you begin the “Internal” part of your setup then you will automatically eliminate all of this time from your setup. This first stage of your quick changeover will often save around 50% of your setup.

Separating the External and Internal Activities

Identifying internal and External setup information

Video recording equipment is no longer something that is expensive nor difficult to use, so being able to video the setup from more than one angle is going to be relatively simple. Ensure that the lighting for your recording is adequate and have the person doing the recording talk through the process as it is being done. It is far better to do any analysis from a video as it allows the whole team to be able to review the stages of the setup together. The video of course can be paused and process times taken direct from the footage itself if times are required.
From the video recording use the entire team to identify each step of the changeover either using post-it notes as a flow chart or on the worksheet below. For each and every stage identified the team needs to decide if the step is either “I” internal or “E” external which should be recorded on the sheet or on each post-it.
At this stage depending on the experience and capability of your team you may also want to identify those steps that are also Waste. The seven wastes of lean are those steps within the process that you are observing that do not add any value whatever to the product or process. So moving and fetching would be considered as waste.
If you have more than one shift then it is always worth videoing each shift and repeating the exercise for each. You can then compare the different shifts to see what they do differently.

Download the Quick Changeover worksheet to use in mapping your changeover process steps

Free SMED worksheet download

Click the link below to download and use the quick changeover work sheet

Quick Changeover Worksheet

SMED Worksheet Example

Example of a Quick Changeover Form in use

Using Post Its to Map your Changeover Process

Flowchart your Changeover using post its.

Separate Internal and External activities for the next setup

Next we use the changeover analysis to fully separate the two lists of activities so that all of the external activities such as fetching tooling and information can be conducted before the machine is stopped for changeover. This step without any form of optimization will often result in at least 50% reduction in machine downtime.

Separate Internal and External SMED Activities

Separate all Internal (“I”) and External (“E”) activities so that external activities can be conducted while the machine is still running.

SMED Stage 2

The next stage of our SMED implementation is to look at the external activities that we have separated and to standardize them so that they are done efficiently for each set up. Click the link to discover how to standardize external activities.