Today, another group of five Children's leaders is heading out to Japan with a new mission: to learn about "lean" methods for pulling resources through our various processes (supplies, equipment, etc). It's all about making sure our staff have exactly what they need when they need it, at the right place, in the right quantity, and at the right cost.

The Power of Visual Signals

One of the first lessons learned is that Kanban means visual signal. As our delegation spent our first full day (Sunday) in Tokyo we discovered a common sense of empathy with Children’s families. Families arrive at the hospital doorstep even less prepared for the language, culture, and rules of the hospital than our group in our first day in Japan.

In downtown Tokyo we found that simple things can be confounding if you do not understand the language. At a buffet line we were challenged to open the lid on the electronic rice cooker when all the buttons were labeled in Kanji. We abandoned the rice option feeling child-like in our inability.

Our team discovered the magic of symbols and pictures paired with willing, helpful people. With these aides we were able to take subways, buy items and for the most part order what we wanted for dinner.

We plan to take this experience back to Seattle and hopefully see the world of Children’s a little more through the eyes of the Spanish speaking family from Yakima, or the Alaskan mom and daughter that in the day prior were in the clinic of their remote Aleut village. Based on this experience we will be looking for evidence of signs, symbols and helpful people that will translate and assist these families in the foreign land and experience at Children’s.

In the days ahead will we be working through simulations featuring the different types of Kanban systems. After the simulations and lectures we will be visiting factories such as Yamatake, a supplier of bathrooms to the Boeing 737, to actually work through the process of extending the number of kanbans used in their plant.

The challenge ahead is first to thoroughly understand the Kanban process and then start to dream about the applications. We look forward to sessions involving quite a bit of math and hoping that in the instruction we will have plenty of signs and symbols.

Tuesday was all theory. Lectures on the Kanban applications, simulations, and case studies. Kanban involves looking at demand looking at stable level loaded processes, establishing Takt time and making calculations on the number of Kanban cards and reorder points.

We started our day at Yokohama Bay and had a chance to see many of the Kanban applications we have been taught and seen simulated in the two day prior. Yesterday’s progression had us on the factory floor at Yamatake. Yamatake is a manufacturer of control valves, flow and pressure meters. In business for thirty years, the company has embraced Lean manufacturing but admit that they have much to improve in their Kanban application. We broke into three teams mixed with members from Children’s, Park Nicolet, and Genie Industries, and hit the manufacturing floor. We studied our assigned line operations. We looked at the supplies and activities in an attempt to make recommendations to improve flow through the use of Kanban and Heijunka. We adjusted operating start times, expanded the supply distribution role (Water Strider) and recommended that the operations move from box Kanban to a Kanban/Heijunka Production board. We presented how our models would improve efficiency and were happy with our breakthrough work. After the presentation, Sensei Niwa thanked us for our efforts and saw fit to give us a C- for our recommendations. Sensei Niwa emphasized; “Reduce the number of Kanbans. Kanban should be the express train through the factory. The important lesson is to keep the operator at the station, use water striders to move materials. “Continuous refinement of the process is essential.”

Yamatake managers were not as critical in their closing remarks, quite the contrary. Our gracious hosts walked us back to our bus and waived continuously until we were out of sight. The next morning had us back on the bus headed to Yokohama Rubber company. Yokohama is famous for it’s tires and hoses, which count for 70% of their revenue, but they also produce products you would not expect from a rubber company. The line we visited at Yokohama manufactures lavatories for the Renton built Boeing 737’s. Yokohama uses moving assembly lines and has employed an elaborate Kanban system to move parts from their vendor community through their super market (central stores- like parts warehouse) to their assembly line.

There were obvious maturing improvements in the Yokohama line that we did not see at Yamatake, the management at Yokohama stated clearly that they have a lot to learn with many more iterations of Kanban ahead. Their Takt time is currently at 110 minutes which results in 90 minutes of overtime each day. Their Kanban supply board revealed that several part deliveries expected from their vendors were 2 - 4 days late. An obvious needed for improvement, at least the problem is visible and being managed.

All these companies showed a journey with Kanban development which parallels the entire lean experience. Tomorrow we will be visiting Toyota, the un paralleled senior organization in Kanban.
Later in this week we will be looking at the Supply Chain Value Stream to discovery the various applications of Kanban at Children’s. We know that Kanbans will be a journey of trials and constant refinement requiring that we look hard at establishing predictable and leveled demand.

Kanban - A system that ensures the required parts are received when they are needed in the volumes they are needed.

At the end of this Kanban instructional journey are the Black Belts of Kanban, the Toyota plant and one of its primary suppliers, Toyota Boschoku. Toyota Boschoku started in 1914 as a spinning and weaving company. The production line of the Toyota Tsutsumi plant (making the Camry and Prius) communicates to the Boschoku via e-Kanban in a continuous fashion during the working day. This kanban notification to Bobuschoku set their paper Kanbans into motion. Boschoku is the supermarket for the Car assembly line and they have various production lines within their factory.

Boshoku make 610,000 pieces monthly, for 23 different customers. Boschoku has 180 inventory turns per year. This means that they deplete and replenish their inventory every 18 hours. In order to do this they must be completely in sync with their customers demand on a moment by moment basis. Kanban helps them make this connection. Each day they handle 20,000 kanbans.

One application of the kanban was in support of one of the assembly cells. This was a one person work cell. A kanban card was swiped by the operator and the materials were provided to him. The materials were perfectly positioned for his work and included the standard work instruction for the piece he was assembling, appearing on a monitor directly in front of him. To his right the correct tool tray was automatically unlocked for use to make sure he had the right tools (poke-yoke).

The plant has all the lean elements to perform significant manufacturing. They focused on flow, die turnover and making sure that they meet customer demand. A strange similarity is that the Toyota Boschoku plant building has a serrated roof line that looks exactly like the symbol for “supplier” in our Value Stream Maps.

The main event was shown in the Toyota Tsutsumi plant. Receiving shipments every hour during the workday, they quickly use and refill the 30,000 parts required to build a Prius or Camry. They build 34,000 cars per month at the plant in two shifts. The goal for the line we observed was 288 cars. They were running at 97% of this goal as we observed the process in the afternoon. The takt time for the line has a car finishing every 3.3 minutes. Their lead time is 20 hours.

Dollies holding parts and tools accompanied the body down the line. Just like in the one-person cell each station had an instruction sheet for the particular car at the station. Kanbans were so integrated in the flow of materials that it was hard to see any differentiation between the kanban and the arrival of the materials.

One place where they did not use kanban cards was in final door installation. Each door was perfectly matched to the main vehicle body. The doors were removed after painting to allow improved access for installation and to avoid cosmetic damages. The removed doors continued along at exactly the same rate as the body and they arrived in the precise order needed at exactly the right time. The kanbans are unnecessary.

Tomorrow we will be discussing lessons learned and steps for Kanban at Children’s

Kanban - A system that ensures the required parts are received when they are needed in the volumes they are needed.

At the end of this Kanban instructional journey are the Black Belts of Kanban, the Toyota plant and one of its primary suppliers, Toyota Boschoku. Toyota Boschoku started in 1914 as a spinning and weaving company. The production line of the Toyota Tsutsumi plant (making the Camry and Prius) communicates to the Boschoku via e-Kanban in a continuous fashion during the working day. This kanban notification to Bobuschoku set their paper Kanbans into motion. Boschoku is the supermarket for the Car assembly line and they have various production lines within their factory.

Boshoku make 610,000 pieces monthly, for 23 different customers. Boschoku has 180 inventory turns per year. This means that they deplete and replenish their inventory every 18 hours. In order to do this they must be completely in sync with their customers demand on a moment by moment basis. Kanban helps them make this connection. Each day they handle 20,000 kanbans.

One application of the kanban was in support of one of the assembly cells. This was a one person work cell. A kanban card was swiped by the operator and the materials were provided to him. The materials were perfectly positioned for his work and included the standard work instruction for the piece he was assembling, appearing on a monitor directly in front of him. To his right the correct tool tray was automatically unlocked for use to make sure he had the right tools (poke-yoke).

The plant has all the lean elements to perform significant manufacturing. They focused on flow, die turnover and making sure that they meet customer demand. A strange similarity is that the Toyota Boschoku plant building has a serrated roof line that looks exactly like the symbol for “supplier” in our Value Stream Maps.

The main event was shown in the Toyota Tsutsumi plant. Receiving shipments every hour during the workday, they quickly use and refill the 30,000 parts required to build a Prius or Camry. They build 34,000 cars per month at the plant in two shifts. The goal for the line we observed was 288 cars. They were running at 97% of this goal as we observed the process in the afternoon. The takt time for the line has a car finishing every 3.3 minutes. Their lead time is 20 hours.

Dollies holding parts and tools accompanied the body down the line. Just like in the one-person cell each station had an instruction sheet for the particular car at the station. Kanbans were so integrated in the flow of materials that it was hard to see any differentiation between the kanban and the arrival of the materials.

One place where they did not use kanban cards was in final door installation. Each door was perfectly matched to the main vehicle body. The doors were removed after painting to allow improved access for installation and to avoid cosmetic damages. The removed doors continued along at exactly the same rate as the body and they arrived in the precise order needed at exactly the right time. The kanbans are unnecessary.

Tomorrow we will be discussing lessons learned and steps for Kanban at Children’s

Today was a day of reflection from this week of Kanban immersion training. While there are many information nuggets (such as using flexible PVC pipe to construct inventory racks) some of our most significant learnings are listed below:

There must be a stable process to have an effective Kanban system. If processes are highly variable/unpredictable a pure visual signal such as kanban is not effective. This is because the kanban is set on one cycle. The cycle works in a loop, so the loop must be in the same rotation over and over.

The role of the water strider (materials handler moving from station to station). This position allows the operator to focus on their core role/activites, while a resource dedicated to distributing supplies and equipment works around the operator to ensure they have what they need, when they need it.

Kanban at its core is visual. Everything about the kanban system is visually triggered. From the simple information on the card, to the limited flow pattern, everything about the process is easy to follow. The simplier the better.

A kanban should have a single purpose. The kanban triggers resources from point A to point B. It then returns to A for redeployment. It should be considered a round trip non-stop ticket.

Do not start work until a kanban is received and only produce what is requested. Kanban is a vehicle for standard work. If you start work prior to the signal, or work beyond what is required, you are contributing to the waste of overproduction (mira).

Placement of supermarket is key. Systems need supermarkets (inventory hold locations) to maintain flow between supplier and production points. It is critical to understand where the supermarkets are, what they hold, how resources flow through them, and how they are maintained.

Kanbans require continuous refinement. After implementation, assessments of performance become key. It is critical to ensure kanbans flow is controlled. Kanban replenishments should never be too “hot” (requiring many replenishments ) or “stale”, but should always be in synch with customer demand.

Establishing Buffer (safety) stock requires diligent study. Levels of buffer stock accommodate processes variability. However buffer stock should be defined with quantitative tools, reviewed with frequency, and established with purpose recognizing criticality and severity of the item.

Kanban does not create standardization, but it does rely upon standardized processes. Customer orders can be diverse (ie: different models and accessories on cars coming down an assembly line) but the items delivered to support the assembly process should come the same way every time.

Kanban is not a universal tool or solution. It does not fit all applications. It is a vehicle for flow but not always applicable. Sensei Niwa asked the question “Do you need a kanban card to tell you that you are hungry?” You want to develop systems that automatically pull the right supplies. Until you reach the point of innate pull within the system, the kanban can be the right answer.

The Supply Chain team has discussed plans for piloting a simple kanban system based on these learnings that can be started within the hospital and rolled out to the outpatient clinics. The goal is to remove the clinical staff from the supply replenishment process. This can be an iterative improvement on some of the early kanban systems that have been established.

This spring we will be working with our Tauber Institute (industrial engineering graduate students) interns to apply kanban approaches to some supplies in the OR core area and to the case cart process. Included in this work is possibly changing from the notion of case carts to case “kits” meaning that the OR is provided with exactly what is needed, for a case as it is needed. This would be a true kanban application.