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A Systematic Approach to Part Shortages – Part 2

For kanban to work well, there has to be a solid foundation under it. That foundation is production leveling or heijunka.

Before I get to far into this, though, I would like to point something out: At the mention of leveling, people who are only just learning about kanban will point out all of the good reasons why leveling is difficult. Here is a key point: The problems caused by running kanban without good leveling pale in comparison to the total chaos that ensues if you try to run MRP without leveling. I’ll stay out of that little rabbit hole until another day though.

Production leveling has two parts.

  1. Leveling the production volume.
  2. Leveling the production mix.

The operation I described in Part 1 was relatively small, so it was a simple matter to set up a totally manual system to do this. By small I mean they had two major assembly lines running at a rates on the order of 10 units / day. The product was about the size and complexity of a medium to large-sized photocopier (though not a photocopier). The assembly lines had about half a dozen positions each. There were several hundred parts from about as many suppliers. (Different story.)

The objective in leveling volume is for the production line to see demand as an image of the takt time, and to protect that signal from variation in actual orders and shipping. At the same time, the shipping dock was to see deliveries to the finished goods buffer at takt time, regardless of minor and medium problems in production.

To accomplish this they separated the “big lump” of inventory that typically existed in shipping into two physically separate buffers.

The Withdrawal Loop

Customers, unfortunately, rarely order at takt time. The purpose of the buffer in shipping was to absorb this variation and make the actual demand appear as if it arrived exactly at takt. The organization also tried to take out some of the bigger spikes in customer orders by working with dealers to get more transparency into actual customer order patterns; as well as trying to level actual promise-to-ship dates at least weekly if they couldn’t get it to daily. That helped a lot. A more sophisticated order entry system would have worked better, but that luxury wasn’t in place yet.

Back to the buffers. Each unit in shipping had a withdrawal kanban card attached to it. As orders were released, a unit would be pulled from this buffer and shipped. The withdrawal card went back to the production control department. Those cards were placed in the inventory management box. This box had series of slots that indicated authorized inventory levels. A card in one of the slots indicated inventory we didn’t have, an empty slot indicated inventory on-hand.

There were limit markers at near each end of the row of slots. As long a the end of the row of cards stayed between those limit markers, everything was regarded as OK. They did not try to chase a particular level of inventory with production.

The scheduled production rate was 10 units / day.

Each morning Production Control would take 10 cards from their box and put them into the leveling box in shipping. That box had slots that corresponded to times of day. The cards were evenly distributed at the takt-time interval. As that time came up, shipping would take the withdrawal card from the box, go to the end of the production line, attach their card to a unit, and move it to the shipping buffer.

This seemed like a lot of trouble, but it served a purpose. It was to hide the irregularities of shipping schedules and actual order dates from assembly. They saw a clean, paced signal exactly at takt time. The process was designed so that assembly saw a perfect customer, even if the customers were far from perfect.

If management didn’t like the size of the shipping buffer, they knew exactly what problem(s) must be solved to reduce it – they needed to improve the dealer ordering and management processes so dealers would stop using deep reorder points and ordering weeks worth of product at once.

The Production Loop

When units were withdrawn from the end of the line, they were actual pulled from a FIFO buffer. In this case, the buffer held about 4 hours of production. Why? Most problems in production were cleared within that time. Only a bigger problem would starve the buffer and affect the withdrawal loop. Thus the purpose of this buffer was to make assembly appear as a perfect supplier to their perfect customer. They could supply exactly at the agreed-upon takt time.

Each of these units had a production kanban card attached to it. When shipping came to pull a unit, they would pull the production card and leave it in a kanban post. They would attach their withdrawal card and take the unit. Thus switching the cards transfers ownership of the product from one loop to the next. Since a kanban card authorizes a specific quantity to be in a specific location, if someone wants to take something somewhere else they need to attach a card authorizing them to do so. That was the case here.

The production cards went to the front of the assembly line. There were three slots there. One green, one yellow, one red. If everything was running smoothly, the card would go into the green slot, and when the next unit was started, the card would be pulled from the box and attached to the unit.

If the line were a little bit behind, there might still be a card in the green slot. Then the next card would go into the yellow slot. This would automatically signal the assembly manager that there was something that needed some attention.

The next card would end up in the red slot. This was the point when, if they weren’t already there for a known problem, they were in “line stop” mode. Anyone who could be helping to clear the problem should be helping to clear the problem. Why? The money machine has stopped running. Everyone is now being paid only because the shareholders are lending them money. The idea is to get the money machine running as quickly as possible, and it is the most important thing. This was a simple phased escalation process, and was part of their overall andon / escalation system.

Did it work?

All I can say is that it worked a hell of a lot better than what they were doing before. It took two or three serious tries to get this into place and keep it working, and they probably fell off the wagon a couple of times after that. There were always immense pressures to “reduce inventory” at the end of the quarter, for example, which would have management directing to starve out the shipping buffer, or push it out early. But, in general, when it was working, overtime was lower, things were more predictable, problems were identified very quickly.

But…

Yes, it looks like a lot of manual work involved. But I want to be really clear – the total time spent moving all of these cards around was a fraction of the time that had previously been spent investigating status, working action messages, making calls to find out what was happening, etc, etc. For some reason people seem to think that deliberate activities raise the total amount of labor involved, and that somehow, the time spent running after information and chasing problems is free.

Setting a standard and following it injects an element of stability and calm into an otherwise chaotic workplace. Once this basic foundation is in place it is far easier to improve overall efficiency because now there is an actual process to improve.

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A Systematic Approach to Part Shortages – Part 1

The short story of assembly problems is lack of parts. Part shortages drive all kinds of waste, including: juggling the schedule; expediting; bigger lots or batches – and all of these things end up causing shortages later on in a self-reinforcing death spiral.

So how did an assembly shop which built about 10 units / day, and suffered between a dozen and 20 line-stopping part shortages a day end up eliminating all but a few (3-5) a week?

Three things, more or less at the same time. This post talks about the first:

Implement a kanban system to replace MRP ordering. They systematically studied how kanban is supposed to work, and, over a few months, put in a kanban system which I am proud to say was really pretty good. The assembly line was fed by kit carts which were picked at takt time from a small supermarket on the shop floor. The supermarket held a day or two of parts. The parts with local suppliers were replenished right from the receiving dock. Parts which had to still be purchased in larger quantities were stored in a warehouse area, and the shop floor supermarket was replenished from the warehouse daily.

The daily warehouse replenishment established the concept of isolating the problem. Their daily replenishment allowed them to set up the shop floor supermarket as if all of their suppliers were delivering daily.

All parts in the shop-floor supermarket and the warehouse were under kanban control. This means they had kanban cards physically attached to the parts (if they were separate) or the containers.

Some things they learned over time:

  • The rules of kanban state that the card should be pulled and placed in the post when the first part is removed from the container. The quickly learned this was far more likely to happen if they secured the card in a place where it was in the way of either opening the container (over the folding lid, for example) or had to be moved (e.g. picked up) to get the first part out. At that point the card is in the person’s hand and he has to put it somewhere.
  • The number 1 reason for lost cards was that “put it somewhere” was a pocket.
  • The number 1 reason why the card ended up in a pocket was that the kanban post was more than a step away from the place where the card was pulled. That meant the person put it in the pocket “for a second” while he got the parts.

In the above case the countermeasure was simple. Put kanban collection points everywhere where parts are handled.

  • The first time they tried putting a pull system in for parts ordering they hadn’t put in heijunka (production volume and mix leveling) first. That was a problem, and “problem” is an understatement.

The countermeasure was (obviously) to simultaneously implement a schedule leveling system to drive the upstream system at takt. More about that in Part 2.

  • They invariably had some parts where they had more than they needed.

The countermeasure was “black cards” (though I would have preferred bright orange cards) that signified “excess inventory.” These cards allowed them to maintain kanban control of all inventory, but they did not signal replenishment.

When a card was pulled, the shop floor coordinator would scan a barcode on the card. This scan triggered an order release to the supplier, and authorized the supplier to ship the indicated quantity.

Actual card from this organization being scanned.
Actual card from this organization being scanned.

They had agreements with the suppliers that there would be an email acknowledgment of the order within 2 hours. When the card was scanned, it was placed in a slot labeled with the time when the acknowledgment was expected. When (if) that time passed and the acknowledgment had not been received, the card went to the buyer who phoned the supplier. “Did you get my order? I need the acknowledgment within 2 hours like we agreed.”

This served two purposes. First, it verified receipt of the order and eliminated a known cause of shortages. Second it “trained” the suppliers that this time the customer actually expected them to honor the agreement. They really didn’t want that call from the buyer who had better things to do.

Once the acknowledgment was received, the card went to the receiving dock. Here it was placed in a slot that indicated the day (and later on, the time window) when those parts were supposed to arrive.

Like the above case, if the time passed, the card went to our poor hapless buyer. He phoned the supplier with a simple question: “Where’s my parts?”

This reinforced that, once again, there was an expectation to honor agreements. They really didn’t care that much (at this point) what the supplier’s lead time was. Only that it was honored. The main objective when starting out was simple consistent execution.

When the parts came in, the card was retrieved, matched with the order to verify, then scanned again to trigger a receipt transaction. If there were exceptions – guess what – another phone call.

The card was then attached to the container. Since the card specified the storage location, put-away was fairly straight forward. No location lookups required.

The previous condition had been that there was no matching of receipts against expectations. Thus if parts were late, or didn’t show up at all, no one noticed until they ran out. Big problem. By trapping and surfacing problems at the two main failure points in the system, most of those problems went away after a few months.

For the purists who are reading – yes, this process has some compromises and probably is a bit obsessive on checks. Call those training wheels until there is a sense of balance. All I can say is that it worked and, in the long run, ended up to be a lot less work than chasing down and expediting shortages all day.

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Team Preparation for a Shingijutsu Seminar

If you are planning on attending (or sending people to) a Shingijutsu Seminar, I have a word of wisdom: Prepare.

Just sending people cold and expecting great things from the experience will, at best, give you a fraction of the potential learning. At worst it can turn people off completely. Here is a little advice:

Read my post on “Getting a Plant Tour“

Everything there applies here. Don’t be “industrial tourists.”

Groups are Better than Individuals

Even two people together are better than one alone. Not to say that an individual is going to get nothing, but when there are others to debrief the day and share learnings I think that interaction contributes a great deal to quality of the experience. It also provides a degree of insurance against the possibility of being assigned alone, or with a handful of “singles” to a large team composed of people from the same company. While that is by no means a disaster, it is probably a little easier if there is some assured mutual support rather than counting on finding it there with people you just met – and who may have their own rigorous agendas.

The Basics

It is important to have an certain level of comfort with the basics:

  1. Understand the fundamentals of standard work.
  2. Know how to use a stopwatch and a time observation sheet.
  3. Know how to build a standard work combination sheet, and what it is for.
  4. Understand what takt time is, what cycle time is (and the difference).
  5. Know how to build a work balance chart.

They teach all of these things in the first day lecture, but (trust me) the more you know before you get there, the better you will be able to follow what they are teaching.

A Theoretical Base

Once again, the more you know before you go, the better. Even if you are working a complete implementation, it works well if your team is focused on a specific aspect of learning. Since everything in the system is inter-connected anyway, this does not limit your experience, it just focuses it.

Whatever your chosen topic, have the team members to some research and study, make presentations, and generally gain a level of understanding. This will help everyone make sense of what they see and hear in Japan since they will at least have a context for it.

Touring Toyota

Generally, one of the features of these trips is a tour of a Toyota plant. The tour is the same 50 minute tour everyone gets, there is nothing special. In fact, on this last trip, we were asked to leave our Shingijutsu name tags and any Shingijutsu-specific materials on the bus – not sure why, but I can speculate.

Rather than everyone just getting the tour, here is how to make the most of it.

Assign four sub-teams. Each one is focusing on a specific aspect of what you will see.

  1. Standard work / the flow of people.
  2. Pull and the flow of materials.
  3. Tools and gadgets that make the work easier, assure quality (poka-yoke) – technical kaizens
  4. The flow of problems – the andon system and the response.

It is good to get the theoretical base in these things before you depart, so people have some idea what to expect. This is the Plan of Plan-Do-Check-Act. They are establishing a “should be happening” in their minds. Doing so will focus their observations. Whatever they see will either confirm what they think should be happening, or will contradict it. Either way, they will remember much better.

After the tour, each sub-team should debrief themselves, then report to the larger group what they saw and what they learned.

Note that this doesn’t mean that people focused on, say, kanban would ignore andon and line stops. Quite the contrary. The system is highly inter-connected. But having focus helps people see.

Get a Custom Experience

This is a bit of an advanced topic, and perhaps is a little redundant. I say that because if you know how to arrange this, you already know what I am going to say here. The boilerplate seminars are probably not the best solution if you know what you want. If you have a client relationship with either of the Shingijutsu’s, they have proven agreeable to setting up a custom experience. This is especially true for top-level leadership teams and advanced topical training.

Shingijutsu is not the end-all

It is true – Shingijutsu, especially some senior individuals, can be a challenge to deal with. There are other consultants today who have the connections and contacts to arrange the “Japan” experience. I have no personal experience, so cannot specifically advise, but some have quite good reputations. Still, I would strongly advise performing your due-diligence, and ensuring you still have good preparation. I would also advise having someone on your staff, or someone you trust, who knows the business do some of the vetting for you.

Another option is that there are independent consultancies who have relationships with Shingijutsu. Frankly, mere association with Shingijutsu, and even using “Shingijutsu” in the name does not assure quality or competency, but they are out there, have the relationships, and might be able to get you started.

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Thoughts from Nagoya: Japan, Toyota, Shingijutsu

Nagoya Castle

This last road trip was 3+ weeks in China, then a week at the Shingijutsu seminar in Japan. It was a little fortunate for me since I was the only member on our team who was not suffering from 8-12 hours of jet lag.

As I noted at the start of the Shingijutsu Seminar series, Shingijutsu Co. split along factional lines a few years ago. I did not get an opportunity to get into details with anyone I know who would tell me, maybe I will inquire about the juicy details later on through correspondence. Anyone who does know is welcome to comment below.

Nakao-sensei’s group is now based in Nagoya and has a USA office in Portland, Oregon. They call themselves “Shingijutsu USA.” The other Shingijutsu goes by “Shingijutsu Global Consulting” and is headed up by Niwa-Sensei. Although I have no personal experience with this organization, I have some reliable second-hand information that they are a little much better at organizing the seminars and training activities. I also get anecdotal information that there remains a great deal of bad blood between the two groups, though some of that is egos and personalities of certain individuals who need not be named as if you care, you know who they are.

One of the interesting things we did on Thursday after the report-out was visit to the Nagoya office. The feature is stand-up desks made from the modular tube structure available under several different names. The same material is used to make racks and carts at Toyota as well as many other companies, but this is the first time I have seen it used to make office furniture. I will let the photos speak for themselves.

Shingijutsu Office Tour Shingijutsu office

This is obviously not for everyone, but it works for them, and that is what is important.

The opposite side of the office is floor covered with a tatami mat and a traditional table.

Toyota Museum

I mentioned the Toyota Museum a couple of days ago. If you plan on visiting, plan on about 4 hours. We did not have enough time on the planned itinerary. I have been there before and still would have liked to spend another hour on the site. Good museums are like that.

Japan

The last time I was in Japan (except for stopovers at Narita) was 2000 on a similar seminar. That time we had two weeks in-country, and more time to get out and about. Still, eight years is more than enough time to get a sense of where a country is going. The mid- and late- teens of 2000 are well into the workforce now. While it is still clearly Japan, I also got a sense that things have continued to loosen up a bit, for better or worse. There are also more people on the streets with a few extra pounds than before.

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Assessing Results vs. Reflection

As we near the end of 2007, most of our respective organizations are looking at what we are going to do in 2008.

Part of that is usually to take a look at this year and look at where we are right now. There are a couple of ways to go about this, and I want to contrast them. This is based only on my own personal experience and, of course, your mileage will vary.

All too often I think this process consists of reviewing results vs. goals. The emphasis is almost solely on targets and actuals. The target was hit or not hit. Top leaders are not interested in “excuses.” I have seen particularly destructive forms of this that included going so far as to re-define success to match what had been achieved. The baseline was re-set at the beginning of the next year, and everything in the past forgotten. Managers took full credit for cost reductions which were “achieved,” not through their own actions, but due to fluctuations in commodity prices of raw materials. Likewise, managers were assigned blame for not hitting targets for the same reason if those prices went up.

There was no review of progress of activities which were predicted to achieve specific results, nor was there a prediction that specific activities would lead to specific results. Instead there was a general high-level target, then a list of actions. Since none of those actions was tied to a verifiable outcome or target, there was no way to know what worked and what didn’t.

Even worse, it really didn’t matter. As long as the targets were achieved, that was what counted. There were great negotiations about exactly how targets would be measured (this company measures everything, and measures nothing). Then, for example, if inventory reductions were to be achieved over the year the actions taken were: (1) Shut down production processes to starve the system. (2) Pull 1Q orders in to 4Q to book the sales. Ships were loaded and sent early because the inventory cleared from the books – even though this was intra-company shipment. They had a LIFO system, so the deeper they could reach into inventory for sales the higher profit they could make since the older the inventory the “lower the cost” associated with it.

All of these games were driven by a “hit the targets and don’t ask about how” mentality. By the way, when 1Q results rolled around things were dismal because they had pulled orders forward PLUS starved the system by shutting down production in 4Q.

This management system is designed intended to deliver results to Wall Street, though it really doesn’t Such is the corrosive nature of trying to manage to “shareholder value” using traditional cost accounting methods. Yes, shareholder value is important, but you can’t manage to it and expect to get the kinds of results that customer and processed focused companies do.

Reflection

Reflection is a learning process. It is designed to incorporate what was learned into shifts in approach for the future. Without it, learning is, at best, an individual action. At worst, the learning is how to survive in the system, not how to do better.

The three key questions are:

  1. What did we intend or plan to accomplish?
  2. What was actually accomplished?
  3. Why the difference?

At a deeper level:

  • Did you accomplished the actions you intended to accomplish? If so, how did that go? What obstacles did you have to overcome? If not, what got in your way that you could not clear?
  • Did each of those actions deliver the expected or planned result? Are you sure? It is just as important to understand why you succeeded as it is to understand why you failed. The commodity price example above is an example of the opposite. They succeeded, but didn’t acknowledge that it wasn’t through anything they did or didn’t do. If an action did not deliver the anticipated result, why not? What did you learn?

Planned? Actual? Please explain.

This is nothing more than the application of PDCA and the Scientific Method. Your plan for the year consisted of a designed experiment. “If we do these things, we expect this results.” Then do that thing, and check that you actually did it. Compare your actual result with the expected result. Explain any difference. Learn.

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Toyota Museum Display: Universal Design

One of the displays in the Toyota Museum in Nagoya was an exhibition on “Universal Design.” This exhibition runs through December 2.

Rather than trying to interpret and articulate the concepts, I just want to list some of the key words. I think they stand for themselves, and provide a good baseline for evaluating the design of anything which must interact with humans.

  • Easy to see
  • Easy to hear
  • Easy to use
  • Easy to understand
  • You don’t have to be strong
  • Comfortable posture
  • OK for almost everyone
  • Equitable use
  • Flexible in use
  • Simple and intuitive
  • Perceptible information
  • Tolerance for error
  • Low physical effort
  • Size and space for approach and use

The exhibition highlights design concepts and features that make products (particularly automobiles, obviously) .

They talk about the physiological value of the product, in addition to the physical value. This is the linkage between the things which provide physical comfort and accessibility through the things which provide “comfort and peace of mind” – the things which assure the user (driver) that things are OK.

Things which people must see include special attention to the view through aging eyes. I can personally attest that things look different through the eyes of a 50+ year old than they do to a 20 year old. Contrast is reduced, as is resolution. Choices of fonts, sizes, colors are more important.

Even outside of automotive, if you are designing anything which needs humans to pay attention and interpret information, it is important to apply a little thinking into what they (humans) actually see, and what sorts of things penetrate consciousness and get the attention of someone who isn’t that attentive right now.

This carries back to the concepts I outlined in an earlier post “Sticky Visual Controls.” Of course a “visual control” is (or should be) also audible if you want someone who is otherwise distracted (or looking in another direction) to see it.

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Shingijutsu Kaizen Seminar Day 5 – Toyota Museum, Toyota Tour

Friday was a visit to the Toyota Museum in the morning and the “1 hour tour” of the Tsutsumi assembly plant in the afternoon.

Toyota Museum

If you ever get to Nagoya, the Toyota Museum is superb and definitely worth a visit. Even if you have no interest at all in lean manufacturing (so why are you reading this??) you get a really good look at over 100 years of technology development in the weaving industry, as well as their automotive history.

Sakichi Toyoda was one of Japan’s greatest inventors. Starting at the end of the 19th century he started incorporating mechanical assist and then automation into weaving looms. Remarkably his inventions were the first significant advance in weaving technology since John Kay invented the flying shuttle in 1733. Most of Sakichi’s principles remain today. There have been engineering advancements, but the basics are all still there. It was patent licensing of his first fully-automated loom with auto shut-off (jidoka) — the Model G in 1924 — that capitalized his start into the automobile business.

But I have to give credit to Gregg, one of my team-mates here, who summed it all up in one profound sentence:

“… all of this started with a son trying to make life easier for his mother.”

Wow. and Yeah. That insight really got to the core of what kaizen is about – a passion for making the work easier, because people’s burden matters.

Tsutsumi Plant Tour

Just to be clear, this is exactly the same tour that any group gets. There is nothing particularly special. The bus is boarded at the gate by the Public Relations girl (they are always young women), and she starts the spiel. We are on the catwalk over the line following a specific route.

So what did I see?

Wow. And that is not just because it was a Toyota plant, been on this tour before. The “Wow” is that they have made a significant change in their material conveyance. This may be old news to you, but I was last in this plant in 2000, so it was new to me. Previously they had line side racks with stocks of parts for the various models and options. The assembler looked at the manifest for the part code, and picked the appropriate parts for that car from the bins and installed them.

Later on I know they placed RFID on the car roofs which tell the various poka-yokes in the work station what the car needs, but the pick method was not fundamentally different. Kanban replenished the parts are they were used. (more about the RFID in a little bit.)

Now they are kitting car-specific collections of parts and sequencing them to the assembly stations. This is significant because I am a big fan of picking kits and delivering them to assembly at takt. There are a lot of possible problems which are mitigated or eliminated when this is done. But I had always conceded that at some point, takt time was so quick that it might not be practical.

I stand corrected. Here is an operation picking and delivering kits to many hundreds of assembly positions, one-by-one, at a takt of just under 60 seconds. Wow. The picking process is, well, superb, I am not sure what else I can say about it here. I am going to assemble my thoughts over the next couple of days.

RFID – the Car as Customer

The other really interesting bit was the use of an RFID box on top of every car. The box has that particular car’s configuration and options coded in it. (I suppose it could be a serial number linked to an option list in a data base too, but knowing some basic tenants of Toyota’s philosophy regarding information flow, I would not be surprised if the data were actually carried on the car.)

As the car moves through the processes, each work station basically asks the car “What are you? What do you need?” and the “car” responds through the RFID. The work stations’ poka-yokes and other configuration dependent things then adjust to help the assembler give the car what it needs.

So why not just put the sequence list in the computer and have each one called up as it goes by?

What happens if (inevitably) some small variation causes the list to not be accurate. There are thousands of things that can cause small changes. The second that computer sequence list is inaccurate, the entire system breaks down. And inaccurate it will be. Anyone who has tried to run their factory on detailed MRP blowdown knows what I am talking about.

No, in this case, each car “pulls” the work it requires, when it requires it. The information in each work station is delivered just-in-time, and not one second earlier. Thus the information is always the latest. Note that this is really not a fundamental change philosophically. The car has always carried its configuration information with it on the paper manifest. What is different here is that the computer system is facilitating better kaizen, but the information flow philosophy has not changed. The information travels with the car, not ahead of it.

What about that picking and kitting process? Well – and maybe one of you Toyota guys out there can answer this for me – and I will update this accordingly – but I would speculate that it too is driven by the RFID tags rather than a production sequence list. It is a very simple matter to know how many takt-times of lead time are required to pick the kit and get it to the appropriate station. (Well, it is simple for Toyota who is so takt-pulse driven, it may not be as simple for the rest of us – a kaizen opportunity here – basic stability.)

If it takes 10 takt times to pick and get a kit to the line, then 10 positions upstream of the delivery point the RFID is queried. “What are you?” That tells the system what is needed in +10 positions, and the pick list is sent to the picking area. The parts are pulled, kanban cards posted for replenishment, and the kit-cart sent on its way.. first in, first out, one-by-one to the assembly line.

No calculated lead-time offset. No sequenced pick list created in the morning. No sequenced pick list that will be wrong 5 minutes after it is printed. Robust, problem-tolerant, and simple.

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Shingijutsu Kaizen Seminar – Day 4

Today was the final report-out. In these events this is quite ritualized. Each team has a takt time, and must present a standard work combination sheet that shows the flow of their presentation. Everyone must participate in the presentation. There is a general set sequence for what is shown first, second, third, etc.

Because we only had two days on the shop floor (plus the fact that the host company really wasn’t set up with the background support logistics for rapid idea implementation), a lot of the “kaizens” presented were actually results from simulations. While there is still some learning value, I think that the participants missed something in not seeing what really good kaizen response looks like.

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Shingijutsu Gemba Kaizen Seminar – Kaizen Key Points

The last post was a bit of a narrative, and I think it is appropriate to call out a few key points and express them succinctly.

  • The theoretical stuff all emphasizes “initial process stability” as a requirement for progress. Ohno said “without standards there can be no kaizen.” Mark says – “Without parts there can be no assembly.” Everyone knows this, then goes ahead and tries to implement standard work in the assembly areas. Bzzzzzzzt. Wrong answer. You simply can’t if they are blocked from performing to the standard.
  • Key Point: Stability is often implemented from the outside in. If you have unreliable suppliers, or an unreliable or inconsistent conveyance process, you are going to have to stock the inventory you think is necessary (DO THE MATH!) to buffer you supplier’s issues from assembly operations.
  • Once we started even going through the limited motions of establishing stability in three operations, it was clear that there was available cycle time for the waster strider (mizusmashi).
  • Key Point: Adding a water strider (if done correctly) does not add cycle time etc, to the supported process. There simply isn’t any reason NOT to do it.
  • Once again the standard work combination sheet proved to be one of the most valuable, least understood, and least used tools in the kit.

One of the features, if you can call it that, of attending these seminars is that you go home with a nice stopwatch. In this instance, the stopwatches have a lap-time recording feature. You can leave the watch running, click the left button, and it records the elapsed time for each sub-event.

Intuitively this is useful for cycle time studies, however I found a few disadvantages from the old way of recording the continuously running time on the sheet and breaking down the individual times later.

  1. If the work cycle never varies you can happily click away at each observation point and you will get great cycle times. But if there is variation in the work cycle itself, you are hosed. The stopwatch only records times for “LAP-002; LAP-003” etc. Taking times on a sheet of paper allows you to record what was actually happening even if it varied from the work sequence you originally wrote down.
  2. Press the wrong button at the wrong time and you lose it all – the stopwatch clears. Actually I think the lap times remain in memory, but still, I am not comfortable with this. Make a mistake on a paper time observation sheet and you can recover. Even if you accidentally stop and clear the watch, it is easy to recover by re-starting the total elapsed time baseline.
  3. Maybe I am old school here, and I admit that I have lots of practice, but by the time they were finished explaining how to get the lap times out of the stopwatch and write them down, I had already calculated all of the component task times, total cycle times, and was finished.

The bottom line with the stopwatch bit is that I believe they would better serve their clients’ education needs by teaching the running-time method. Anyone who gets a lapping stopwatch can figure out how to do it the other way. The running time approach does require practice to get down. But I think it is more robust. YMMV, that is just my opinion.

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Shingijutsu Kaizen Seminar – Day 3

Yesterday I told you the plan for today. Here is what really happened.

We got the even pitch going for a while. I was at the front of the line releasing units down the line as the pre-build Team Member was done with them. I was watching distance (since distance = time on a moving line). As the previous unit hit the pitch first pitch line, I launched the next. One of the little discoveries was that the conveyor has a “slow spot” that really changes the speed. Oh – and that happens to be when we measured the speed yesterday. Net result? The units were actually fired down line about 10% faster than they should have been. Oops.

Next discovery? Nobody noticed. So much for this great labor bottleneck. There were line stops, but they had nothing to do with this.

In the first position, our experiment to actually present parts at the point of use cut the team members’ work cycle. How much depends on the situation. His work cycle previously varied all over the place – easily by 100% or more when he had to go look for parts and wasn’t sure where they were.

By simply stabilizing his work, we cut his cycle time to well under the takt.

We ended up not recording line stops, but on the other hand, there weren’t any actual andon calls today. That is both good news – nothing we did really disrupted things – and bad news – their system has serious issues, and none of them trigger andon calls.

The kaizen team members studying the semi-automated test operation designed and proved a work sequence that not only handled this bottleneck process, they cut it nearly in half. It can be done well under the takt time if the Team Member and supervisor don’t panic and try to work ahead. If they do, it disrupts everything for two or three units. To “pay” for this improvement, the kaizen team members shifted a (very) small amount of work to the next position down line. All he has to do is disconnect the test equipment. That gives our team member of focus the time to start the next unit right away. Disconnection takes only a few seconds, and easily fits into the work cycle of this team member.

Another sub-team worked on the sub-assembly process with similar results to the first team. By actually making sure all of the parts are present and presented well, the terrifically unstable cycle started to get consistent. There is a lot of work here, and honestly I think the best solution is to break up the sub-assembly cell and get these processes operating right next to the assembly line. There are huge advantages in information flow (they could just look upline by two units and see what they needed to start next). There are huge advantages in material conveyance – there isn’t any. Quality issues would be spotted immediately and could be addressed immediately. Lots of other advantages as well.

This evening we worked on the final report-out. Since this is a Shingijutsu event, there is a fairly rigid pattern for how these report-outs should go. The team spent until about 10:30 working on it and having it reviewed by sensei. I think we got off pretty clean in that department since I already knew the drill, coached the team on what was important plus sensei knows me from past events. I have seen draft report-outs thrown across the room in the past – not especially effective communication in the details, but the big picture, “this is not acceptable,” gets across fairly clearly. That didn’t happen this time. I think Shingijutsu as a company, is mellowing out a little. It is too hard to actually say, but time will tell.