The Lean Thinker's Blog

The Lean Journey

Lean Tweets/Links of the Week 19.07.10

Well as I am currently travelling the world (currently in Adelaide, Australia) so my tweeting and blog updates have been few and far between. For this reason I have been unable to create my own blog posts, so will just post some links to other blogs and websites, which may prove interesting for the Lean enthusiasts out there.

As a side note if you aren’t already get following me on twitter, please do as I love being part of a growing network of Lean thinkers: TheLeanThinker. I always follow back Lean/management tweeters, so I may include your best tweets in future LTOTW.

So here goes:

1. Quite a long post, but its a good read, and even includes some videos to keep even those who lack concentration interested:
2. Lean culture is about “How”:
3. A great post from Chris Paulsen, a guy who has some great tweets:
4. Nissan – LAME or Lean:
5. A nice post regarding a playscape children’s outdoor toy assembly:

I hope these prove to be enjoyable reads, and if anyone finds some good articles, or other Lean posts feel free to tweet them @TheLeanThinker, or email them to I’ll try and include them in next weeks LTOTW.

Waste in the Office

Yesterday I was speaking to a fellow Lean enthusiast about waste, not waste from the factory floor, but waste in the office. He said that the company he worked for had several issues with office waste, before a Lean action plan was created and implemented.

One major waste which was immediately noted was inventory. As mentioned in a previous post, inventory is one of the 7 deadly wastes, and it is responsible for a whole host of consequences preventing Lean from being as effective as possible. So what was all this inventory waste? Paper, pens, files, and notepads you name it; almost everyone had multiples of these items. This was not through necessity, but purely because people felt the items in the store cupboard would diminish, therefore they must stock up with what they think they need, for weeks/months ahead.

To solve this problem, an amnesty was created, whereby all employees were asked to return all the non-used, non-essential items to the store cupboard. For future withdrawals, a short form had to be filled in, so that the usage levels could be quantified, and abnormal use would be more apparent. It has since been found that the ordering of office supplies has reduced dramatically, and significant cost savings have been made.

Along with the extra materials, it was found that 30% of staff printed out all emails, whether they read them or not. Even if the emails were just short messages like “OK Steve, I’ve updated the information, Thanks”. This was obviously a waste in terms of money, and also reduced the company efforts to be green, as well as Lean. To solve this problem, employees were asked to talk to each other, rather than send emails. This would be done either over the phone, or in person (this company is small, so in one office). As well as a clear reduction in paper usage, communication of ideas and information was much stronger. I can see some Lean thinkers screaming “Motion” or “Movement” with regards to employees walking around the office to chat to one another, however the office, as mentioned above, is small, and the benefits of improved communication counterbalanced this extra movement of staff. As a side note, the emails also had a default message attached to the bottom, explaining that people should “think before they print”.

Within the emailing system we found that the response to emails was not particularly prioritised. Due to the employees receiving a large amount of emails per day, we found that to help the recipient prioritise their mail, in the subject a deadline date should be included. This allowed staff to instantly identify more urgent emails, before they even opened them. To further the email waste reduction, we also said that all emails should have been read at least once before the end of the day. This meant that urgent emails were acted upon instantly, otherwise they were placed into folders such as: “By end of the day”, “By end of the week”. This meant that employees could organise their time and emails accordingly.

So to summaries, if you’re constantly reordering highlighters maybe it’s time to see where they’re all going. If you’re bogged down with emails, perhaps just go see the person you need to see, as a 5 minute discussion may save you 10 emails back and forth.

p.s. For 5 simple and quick email tips, I found a nice website here: 5 fast email productivity tips.


Jidoka, although no direct translation, it is thought of as autonomous defect control. A way in which the process can be developed to prevent defects happening, and if they do, stop them from propagating downstream.

As Shingo once said “Humans are animals that make mistakes”. This is absolutely true, therefore people cannot be assumed to spot or prevent all instances of defects. The need to create a self-assessing system is essential, especially when dealing with large scale production and products which must meet strict tolerances.

Jidoka helps reduce waste such as over-processing, over-production, and obviously defects, but not only does it reduce this, it also reduces the consequences of these wastes. These wastes introduce instability by disrupting the flow (Mura), and also stress the process, with the extra effort being (Muri). A Lean system cannot tolerate the consequences defects pose upon it.

In conventional approaches to defects, inspection would be the immediate answer. However 100% inspection is inefficient, costly, and simply not feasible in large scale production. Another typical answer would be SPC (statistical process control) however this also has it’s problems, and cannot prevent all defects from transpiring.

It is also possible to focus on the process, rather than inspecting parts, inspecting the process with techniques such as SixSigma. Jidoka does not discard these options, but it does offer an alternative approach to defect issues.

Jidoka aims to find the root-cause of problems, and make it impossible for them to return. It is an ongoing system of defect control, and therefore should not be thought of as a one-stop fix to problems.

Jidoka has three main areas:

  • Process control
    • A capable process will not create substandard parts
  • Containment
    • Early detection of errors, then preventing propagation
  • Feedback
    • Immediately taking corrective action, once an error is discovered

Jidoka is one of the main pillars in the “House of Lean” and within itself there are 6 main sections:

  • Auto-Stopping
    • Line MUST stop if defects are found. (Although management tend to be against this methodology).  The process should be designed to spot errors and stop automatically.
  • In-Station QC
    • This is simply applying QC within a station or work area, preventing incorrect parts being moved to the next station.
  • Solving Root Causes
    • Often the root cause isn’t obtained, so a method such as 5 Whys should be used here.
  • Person-Machine Separation
    • This allows people to notice abnormal situations,  which otherwise would be moved to the next machine without question.
  • Andon
    • Visual management allows clear and concise feedback information on defects and other relative information.
  • Error Proofing
    • Fool proofing doesn’t exist: fools can be employed, but it is possible to prevent them making errors.  Poka Yoke techniques are key to preventing the possibility of defects.

So what are the action to be taken if an error is found?

The line can either stop, giving sufficient time to solve the root cause, or there can be a warning that a substandard part/component has been produced.  In this case, the seriousness of the defect will command which action is best suited for the situation.

So in summary, we must prevent defects at the source, and if not possible to remove, we must prevent their propagation.  100% inspection is also our aim, but this should be autonomous, not NNVA, as in people inspecting products.  As a last note, use Poka Yoke extensively.

Lean Tweets/Links of the Week 06.07.10

Well, after having my blog chosen for a fellow bloggers Lean tweets of the week, I though I would also like to select my favourite tweets or links and share them here.  I am currently only following around 90 people on Twitter, so the selection of tweets to sift through is rather small, but I have found some great links and articles. Some links will be related to Lean aspects, but often I will include management articles, and other business related material.

Hopefully through this type of community sharing of links and articles, all of the people included will benefit.  If you aren’t already get following me on twitter TheLeanThinker. I often follow back too, so I may include your best tweets in future LTOTW.

So here goes:

1. A nice article showing that sometimes more features aren’t necessary, just a focused approach will prevail:
2. Yahoo sending blank cheques (or checks for those in the US). Have seen this RT a lot lately:
3. A great post about overcoming common problems when creating ‘buy-in’ within employees:
4. A slightly lighter blog post, which provides a more humorous way in which to implement Lean thinking:
5. Another great post from Robert Duckles on the importance of responsive reliable maintenance:

I hope these prove to be enjoyable reads, and if anyone finds some good articles, or other Lean posts feel free to tweet them @TheLeanThinker, or email them to I’ll no doubt include them in next weeks LTOTW.

OEE – Overall Equipment Effectiveness

OEE – Overall Equipment Effectiveness

As my previous blog post was about TPM, I feel that a good place to start for today’s post would be OEE.  OEE is one way to measure the “usefulness” of a machine or operation, and is one of the eight pillars of TPM.  It is used as a key performance indicator in many Lean organisations, and can be used as an indicator of process improvement.  OEE helps quantify the machine in terms of its capacity, against the available time it is scheduled to be running.

The object of calculating and monitoring OEE is to maximise the efficiency, by eliminating waste and manufacturing losses.  The manufacturing losses are:

  • Man
  • Machine
  • Method
  • Material

On top of these 4 manufacturing losses, there are also 6 machine losses (yes Lean has a lot of ‘3 this’, ‘4 of that’, ‘7 of these’):

  • Downtime Losses
    • Equipment failure – repair
    • Unplanned adjustment & setup
  • Speed Losses
    • Idling & minor stops
    • Reduced speed
  • Quality Losses
    • Process out of control (machine)
    • Poor process control (method)

OEE is calculated with the time expected to run, therefore planned stoppages or downtime does not negatively affect the OEE.

So how do we calculate OEE?

A breakdown of the OEE components can be seen in the diagram below:

Breakdown of OEE components

OEE = AF x PF x QF

Total Productivity = OEE x PF

AF = (time available for production – downtime) / time available for production

PF = theoretical time to produce output / actual operating time

QF = (total output – defects) / total output

I apologise now for the poor formatting of the above formulas, but it’s the best I can do on WordPress I’m afraid.

It has been said that if you can measure it, then you can manage it, be that true or not, OEE certainly provides the framework to measure the efficiency of processes, and therefore understand if improvements are being made.  Along with this there are many benefits to OEE:

  • Helps improve manufacturing productivity
  • Helps improve production quality
  • Improves machine utilisation
  • Communicates production status
  • Improves accuracy and efficiency
  • Reduces unproductive labour
  • Improves scheduling efficiency

TPM – Total Productive Maintenance

Lean Maintenance is a relatively new term, surfacing around the last 10-20 years.  However the foundations of this technique were already in place, as TPM (Total Productive Maintenance).  Lean maintenance builds upon the TPM to reduce wastes (Muda) within a system or process.

In manufacturing there are three “laws” which govern maintenance:

  • Correctly maintained machinery will produce more quality parts.
  • Incorrectly maintained machinery creates more parts of questionable quality.
  • Machines left to full degrade will produce no parts.

For a company wishing to implement a complete Lean philosophy it must have stable, reliable machinery.  Without this, processes become unpredictable, waste is created, and Lean principles are difficult to apply.  In Lean this instability or inconsistency is known as Mura.  By definition Lean means the best quality and value, at the least cost.  It stands to reason, that this is not possible if machinery is not running at maximum efficiency.  This is why TPM is a foundation of the “House of Lean”.

Total: This includes everyone in the workplace, aiming to reduce accidents, defects and breakdowns.

Productive: Actions performed whilst production continues.

Maintenance: Keeping in good condition, repairing, cleaning, lubricating.

There are various types of maintenance:

  • Planned (scheduled at intervals or pre-defined points)
  • Unplanned (aka. run to failure)
  • Corrective (returning a machine to correct running state)
  • Emergency (implementing corrective procedures to avoid serious consequences)

When a machine is critical to the overall process, the cost of unplanned maintenance can be significant.

Unplanned maintenance is only suitable when; the unscheduled stoppages cause minimal disruption to the system, or that they are less costly unplanned.  Due to the often random nature of machine failure, unplanned maintenance can’t be avoided, but can be reduced.

Planned maintenance is that which is carried out with forethought, control and the use of records to determine when maintenance is due.

There is also preventative maintenance, which as the name suggests is the application of maintenance at predetermined levels.  This maintenance is intended to reduce the probability of machine failure, or the products being produced at a lower grade.

Often there is the option of opportunistic maintenance, where by machines which are non-operational, or currently broken down can have additional maintenance.  To some extent this can offset the cost of the repair, as no supplementary costs are being incurred.

So what are the benefits of TPM?

  • Increase equipment productivity
  • Reduce downtime
  • Lower costs in maintenance and running
  • Increase plant capacity
  • Reduce amount of machine caused defects
  • Increased return on investment

Visual Management

Visual Management

What exactly is visual management?
Simply put it is a Lean technique which is used extensively to allow anyone entering a work environment (be them trained in the area, or not) to immediately understand the current state of said area.  It should be clear what is in control, and what is out of control.
Visual management (sometimes known as visual control) usually consists of pictures, diagrams, charts or other visual representations of ongoing processes.  These charts can quickly portray how the processes are running in that area/workstation, and therefore act upon any instances of processes deviating from “the norm”.  Many types of VM techniques exist, it is the ability to use the correct ones for each situation which is key.  Here are some examples of VM techniques:
  • Colour coding parts/sections
  • Graphics
  • Kanban cards (to be discussed in upcoming post)
  • Labels
  • Signs
  • Border outlines
  • Checklists
  • Area performance boards (Andon)
Visual management, when implemented correctly, is extremely useful in supporting other Lean efforts.  Here are some of the ways in which VM is useful:
  • Clearly shows correct way of working (thus helping standardisation)
  • Reduces the amount of training needed for tasks
  • Often identifies errors earlier than working without VM
  • Shows performance on monthly, weekly, or daily basis
  • Enables both managers and workers to see TRUE figures
  • Assists in the process being carried out safely
  • Highlights abnormalities in a process
  • Employee happiness, as they clearly understand what is expected of them
  • Increased efficiency due to speed of information transfer
Almost all places of work have some form of VM, although it may not go by that name.  Examples are: no smoking signs, on-site in-out boards etc.  We are more likely to notice these visual charts compared to extensive wordy explanations of correct working practices.
We must be careful to keep these VM techniques clear and concise, as too much irrelevant information can discourage workers from reading them.  This is clearly not ideal.
When using VM it is good practice to involve those within the work area, as they are often the most skilled and can provide the best insight into what VM tools will work best.  Within visual management there are two different categories, controls and displays.
Visual controls guide, or control the way in which an action or process is carried out.  Items such as STOP signs, No smoking, are good examples of visual controls.
No Smoking
Visual Displays are more to do with notifying workers of current states or performance figures.  Often shown graphically, or in charts, as this serves the information quickly and concisely.
In summary, VM is a good way to instigate standardised ways of working, in a way which would otherwise require extensive, tedious, or complicated training.  The usage of VM is almost limitless, and as most companies already unknowingly use some form of VM, they are pre-conditioned to understand the way in which it works.  As stated above, there are many reasons for the use of VM in the workplace, namely the benefits to the efficiency of data transfer.  The faster information can be accessed and dispersed, the quicker preventative, or fool proofing actions can be initiated.