Learn How Kanban Systems are Used in a Lean Manufacturing Environment

Summary

This module from Gemba Academy introduces the concept of Kanban in manufacturing, explaining its origin from Toyota's Just-In-Time production system. Kanban, a Japanese term for 'sign board,' serves as a visual signal for production or movement of items, aiming to prevent overproduction and inventory waste. The video discusses various types of Kanban systems, including the 2-card, 1-card, and 2-bin systems, highlighting their functions in setting production limits, linking material and information flow, and making abnormalities visible. The course promises further exploration into calculating Kanban quantities and managing the system effectively.

Takeaways

• 📚 Kanban is a Japanese term meaning 'sign board' or 'sign', used in production control to authorize the production or movement of items.
• 🚀 The Kanban system is likened to the nervous system in a lean production system, connecting information flow with material flow.
• 🔧 Developed by Taiichi Ohno of Toyota, Kanban was initially designed to prevent overproduction and reduce inventory costs.
• 🛒 Inspired by American supermarkets, the system mimics the 'pull' method of restocking shelves only after products are consumed.
• 📉 Kanban is a foundational tool in the Just in Time (JIT) system, aiming to produce or move items only when required.
• 🔄 The system contrasts with 'push' systems by maintaining a tight chain of production, ensuring the right inventory at the right time.
• ⚖️ Kanban sets production limits, using cards or signals as a form of currency that must be present for production or movement of items.
• 🔗 Kanban physically links material and information flow, making abnormalities visible by ensuring materials are always accompanied by a signal.
• 📊 The classic 2-card system uses production and withdrawal cards to signal the need for product replenishment.
• 📦 The 1-card system and 2-bin system are variations of Kanban that use alternative signals, such as empty containers or bins, to indicate the need for restocking.

Q & A

What does the term 'Kanban' literally mean in Japanese?

The term 'Kanban' literally means 'sign board' or 'sign' in Japanese.

In the context of production control, what does Kanban refer to?

In the context of production control, Kanban refers to the visual signals that authorize the production or movement of items.

Who developed the Kanban system and for what company?

The Kanban system was developed by Taiichi Ohno of the Toyota Motor Corporation.

What was Taiichi Ohno's original aim in creating the Kanban system?

Ohno's original aim was to stop overproduction in his machine shop, which was creating large inventories and costing a lot of money.

What inspired Ohno to create the Kanban system?

Ohno was inspired by the product replenishment methods he observed in American supermarkets, particularly the way shelves were restocked only after products were consumed by customers.

How does a Kanban system connect information flow with material flow?

A Kanban system connects information flow with material flow by attaching Kanban cards to the actual goods.

What is the basic function of a Kanban in a production system?

At the most basic level, a Kanban is a signal that authorizes the production or movement of items.

What is the main difference between a push system and a Kanban pull-based system?

In a push system, production is not based on demand, leading to uneven inventory levels. In contrast, a Kanban pull-based system produces only when required, resulting in a tight, efficient inventory.

What are some of the wastes that a Kanban system can be full of?

A Kanban system can be full of wastes such as excessive handling, inventory, and processing.

What is the ideal Just-in-Time production system according to the script?

The ideal Just-in-Time production system would use no Kanban at all, producing what the customer wants, when they want it, in the quantity they want.

What are the three main functions of Kanban mentioned in the script?

The three main functions of Kanban are: setting limits within a production system, physically linking material and information flow, and making abnormalities visible.

What is the information typically contained on a Kanban card?

A Kanban card normally contains information such as the Part name and number, the Supplier process name, the quantity per container, the Delivery address, the Storage address, and the number of cards in the system.

How does the 2-card system in Kanban work?

In the 2-card system, a withdrawal Kanban signals the need for product from shipping to the supermarket, and a production Kanban signals the assembly department to replenish the item in the supermarket.

What is the concept behind the '1-card' Kanban system?

The '1-card' system uses a signal such as empty containers, carts, or colored balls to indicate the need for replenishment, rather than a traditional card.

How does the 2-bin system function in Kanban?

In the 2-bin system, two bins with equal amounts of goods are used. When the first bin is empty, it signals to replenish two more bins, and the second bin slides forward into position.

Outlines

00:00

📚 Introduction to Kanban in Manufacturing

Ron Pereira introduces the concept of Kanban within a manufacturing context, explaining its function as a visual signal for production authorization and movement of items. The origin of Kanban is traced back to Taiichi Ohno of Toyota, who aimed to eliminate overproduction and high inventory costs by adopting the 'pull' system observed in American supermarkets. The Kanban system is likened to the nervous system of a lean production system, connecting information flow with material flow through attached cards. The module outlines the goal of achieving a true one-piece flow, emphasizing that the ideal Just-in-Time system would ideally not use any Kanban. The functions of Kanban are also highlighted, including setting production limits, linking material and information flow, and making abnormalities visible.

05:02

🔍 Exploring Different Kanban Systems

This paragraph delves into the various types of Kanban systems, starting with the classic 2-card system, which uses production and withdrawal Kanban cards to signal the need for replenishment based on customer requests. The 1-card system is then introduced, which may not use cards but relies on other signals such as empty containers or lights to convey the need for production. The 2-bin system is explained as a method where standardized bins act as Kanban, with an empty bin signaling the need for more parts. The paragraph also mentions the importance of time-based standard work for material supply reliability. The summary concludes with a note on upcoming modules that will cover the calculation of Kanban quantities and the implementation and management of Kanban systems, with a specific focus on the 2-card system in the next module.

Keywords

💡Kanban

Kanban is a Japanese term that translates to 'sign board' or 'sign'. In the context of manufacturing and production control, it refers to visual signals that authorize the production or movement of items. It is central to the video's theme as it is the main subject of the course and the system's foundation. The script explains that kanban cards are attached to goods, connecting information flow with material flow, and are likened to the nervous system of a lean production system.

💡Just In Time (JIT)

Just In Time is a production philosophy developed by Taiichi Ohno of Toyota, aiming to minimize waste by producing only what is needed, when it is needed, and in the quantity needed. The video discusses how the kanban system was created to realize JIT manufacturing on the production floor, emphasizing the importance of producing items only after they are 'pulled' by customer demand.

💡Pull System

A pull system is a method of production where items are only produced or replenished after they have been 'pulled' or requested by the next process. The video uses the analogy of a chain to illustrate the difference between a push system and a pull system, with the latter resulting in a more efficient and waste-free production flow.

💡Overproduction

Overproduction is the production of more items than are needed or can be sold, leading to excess inventory and waste. The video mentions that Taiichi Ohno's original aim for creating the kanban system was to stop overproduction in his machine shop, which was causing large inventories and high costs.

💡Kanban System

A kanban system is a production control method that uses kanban cards or signals to manage the flow of materials and information within a manufacturing process. The video explains that the system gives production control instructions to each work area, making it an integral part of lean manufacturing.

💡Waste

In the context of the video, waste refers to any activity or product that does not add value to the final product but consumes resources. The script mentions that kanban systems can contain wastes such as excessive handling, inventory, and processing, which need to be minimized for an ideal Just-in-Time production system.

💡Kanban Card

A kanban card is a physical or digital card that contains information about the item it is attached to, such as part name, quantity, and delivery address. The video describes how these cards are used to signal the need for production or movement of items, serving as a crucial component of the kanban system.

💡Two-Card System

The two-card system is a type of kanban system that uses both production and withdrawal kanban cards. The video provides an example of how a shaded withdrawal kanban signals the need for product from the supermarket, which then triggers a production kanban to replenish the missing item.

💡One-Card System

The one-card system is another type of kanban system that may not use a traditional card but instead uses other signals like empty containers or lights to indicate the need for production or replenishment. The video gives the example of a mailbox flag as a practical example of a one-card kanban system.

💡Two-Bin System

The two-bin system is a kanban system that uses standardized bins or containers as the signal for replenishment. An empty bin signifies the need for more parts. The video explains how this system works, with one bin being consumed and the signal to replenish two more bins when it is empty.

💡Heijunka

Heijunka is a Japanese term for leveling or smoothing out the production process to avoid large fluctuations in the volume of production. The video mentions the heijunka board, which is a tool used in conjunction with kanban systems to manage the production schedule and ensure a steady flow of work.

Highlights

Introduction to the course on implementing Kanban in a manufacturing environment.

Definition of Kanban as a Japanese term for 'sign board' used for production control.

Kanban's role as a visual signal authorizing production or movement of items in a lean production system.

The origin of the Kanban system by Taiichi Ohno to address overproduction issues at Toyota.

Inspiration from American supermarkets' product replenishment methods for the Kanban system.

Kanban as a tool within the Just in Time system at its most basic level.

Demonstration of the difference between Kanban pull-based system and traditional push system using a chain analogy.

Potential wastes within Kanban systems, such as excessive handling and inventory.

The ideal Just-in-Time production system's goal of producing without the need for Kanban.

Functions of Kanban: setting limits within a production system and acting as a type of currency.

Kanban's role in linking material and information flow through cards or barcode scans.

Making abnormalities visible through the proper use and placement of Kanban cards.

Overview of common types of Kanban, including the classic 2-card system.

Details of the 2-card system with examples of production and withdrawal Kanban cards.

Information contained in a Kanban card, such as part name, quantity, and delivery address.

Introduction to the '1-card' system and its alternative signals to traditional Kanban cards.

Explanation of the 2-bin system where bins act as Kanban signals for replenishment.

How the 2-bin system works with the consumption of goods and signal for replenishment.

Upcoming modules on calculating Kanban quantities and managing a Kanban system.

Next module's focus on the 2 card Kanban system for deeper understanding.

Transcripts

Hi there, my name is Ron Pereira and I'm excited to welcome you to this first overview module

of Gemba Academy's course focused entirely on implementing kanban in a manufacturing

environment.

Specifically, by the end of this module you'll know what a kanban and kanban system are as

well as the different functions kanban can serve.

And finally, by the end of this module you'll understand the many different types of kanban

used today.

So let's get things started by answering the questionů what is a kanban.

Kanban is a Japanese word that literally means sign board or sign.

In the context of production control, kanban refers to the visual signals that authorize

the production or movement of items.

Kanban are sometimes referred to as the nervous system of a lean production system.

Just like our human brains send instructions to our various body parts, a kanban system

gives production control instructions to each and every work area.

It does this by connecting Information flow with material flow by attaching kanban cards

to the actual goods.

The Kanban system was developed by Taiichi Ohno of the Toyota Motor Corporation as a

way to make Toyota's vision of Just In Time manufacturing a reality on the production

floor.

Ohno's original aim was to stop overproduction in his machine shop which was creating large

inventories and costing a lot of money.

Mr. Ohno was inspired to create the kanban system by the product replenishment methods

he observed in American supermarkets.

What caught his attention was the way shelves were restocked with goods only after products

were consumed - in other words "pulled" - by customers.

In the broadest context, kanban is a tool of the Just in Time system.

At the most basic level a kanban is a signal that authorizes the production or movement

of items.

We often use a chain laying on the ground to visually demonstrate the difference between

a kanban, pull based system, and the traditional push system that doesn't use kanban.

When we attempt to move the chain by pushing it we end up with this type of situation.

Just as the chain is uneven and looseů push production systems often create uneven inventory

levels resulting is having too much of the wrong inventory and not enough of the correct

inventory.

But when we pull production through the system, meaning we only produce product when it's

required, the chain is tight resulting in all processes having the right inventory when

they need it.

With this said, kanban systems are far from perfect.

You see, the kanban system can be full of wastes such as excessive handling, inventory

and processing.

In fact, the ideal Just-in-Time production system would use no kanban at all so long

as it produces what the customer wants, when they want it, in the quantity they want.

In other words, our goal shouldn't be to implement a kanban system.

Instead, our goal should be to true, one piece, flow.

OK, let's now move our attention to the different functions of kanban.

First of all, a kanban sets limits within a production system.

You might think of a kanban card as a type of currency that's exchanged for an item much

like money is used to buy parts or materials.

If there's no kanban - no items get moved or produced.

When a kanban system functions correctly, nothing is ever made or moved without a kanban

signal of some kind.

This enables companies to limit the extremely deadly waste of overproduction since things

are NOT produced until they're needed.

In addition to setting limits, kanban also physically link material and information flow

through a card or, as we often see today through a bar code scan.

And finally, kanban makes abnormalities visible since no material should be without a kanban

and no kanban on the shop floor should be found anywhere but attached to the material,

in the heijunka board or in the kanban post box which we'll learn all about later in the

course.

Alright, to wrap up this first overview module let's learn about some of the most common

types of kanban.

The first type of kanban is the classic 2 card system where production and withdrawal

kanban cards are used.

In this example, we see a shaded withdrawal kanban going from shipping to the supermarket.

This is a signal from shipping to the supermarket that it needs product to meet a customer request.

Once the shipping clerk removes product from the supermarket a production kanban will be

sent to the assembly department signaling there's an item missing in the supermarket

that needs to be replenished.

Now, we'll get into this in more detail later in the course but a kanban card normally contains

information such as the Part name and number, the Supplier process name, the quantity per

container, the Delivery address, the Storage address and the number of cards in the system.

A kanban system using cards differs most significantly from the two bin system, which we'll discuss

shortly, in that the card is pulled as soon as the first part is taken.

The next type of kanban system is referred to as the "1-card" system.

And while we refer to it as 1-card there may not be a card used at all.

Instead, we might use empty containers, or carts, or colored golf balls, or ping pong

balls, a light, or really any kind of signal that conveys information.

One of the most practical examples of a one card kanban system is the mailbox flag.

When the flag is up, a signal is sent to the postal worker that there's something inside

the mailbox we wish to mail.

Another system that doesn't rely on traditional kanban cards is the 2-bin system.

In the 2-bin system, standardized bins or containers perform the role of the kanban

card.

An empty bin signals that more parts are required.

The collection of empty bins should follow time-based standard work whenever possible

so that one person can supply the materials reliably for a department or section.

Here's an example of how a 2 bin system works.

It uses two bins with an equal amount of goods inside and the same information on the outside

about the contained goods such as name, location, and quantity within each bin.

Parts are then consumed from the first bin as shown here.

When the first bin is empty this is the signal to bring or replenish two more bins.

The second bin then slides forward into position while two more bins are being prepared.

Finally, a Material handler replenishes two bins within the agreed lead-time which will

obviously be before all the parts are consumed from the second bin.

And while there are other kanban systems, these are some of the most common.

Throughout the rest of this course we'll go on a much deeper journey including how to

calculate kanban quantities.

We'll also discuss how to implement and manage a kanban system.

In our next module we're going to take a closer look at the 2 card kanban systemů so we'll

speak to you soon!