Just-In-Time is one of the lean manufacturing methods that are being used by manufacturer. This method of lean manufacturing tends to reduce the burden of storing excess production and eventually it will improve the cash flows of the manufacturer. There are tools used for this kind of lean manufacturing such as Heijunka, Takt Time, and Kanban, which is also the main focus of the topic.
Before getting into Kanban, there are two type of production for manufacturing which is the pull and push production.
Generally, if you’re a manufacturer and you’re reading this now, you’ll typically be using either a push, pull or combination of both.
Are you able to relate to this? I hope you do.
In the past, most of the manufacture used push production system where they will continuously produce their products send them to buyers that made orders and store the remained production until they receive the next order.
On the other hand, manufactures who uses the pull production system only produce when they receive order from the buyers which is the opposite of the push production system. Kanban is one of many tools that are utilized by manufacturer for their pull production system.
The word Kanban comes from the Japanese Kanji 看板, which means signboards or signs. It was first developed by Taiichi Ohno(大野耐一) a Japanese engineer who worked in Toyota in the 1940s.
The main reason of developing Kanban is to boost the overall efficiency of their manufacturing process. The idea of Kanban was generated from the supermarket, where they restock products that are needed or at least on a specific time for their customer no more or less. However, the similar concept was being used by the UK in during the World War 2 where the 2 bin system was being used for producing one of their fighter aircrafts; it is a straight forward stock refill system.
So, What Is Kanban?
Kanban is essentially a kind of tool that used by manufacture to increase the efficiency of their production line. And this is done by producing the required amount of product based on the supplies demand and also forecast to reduce unnecessary stock holding pressure. Since Kanban is using the pull system, manufacturer will only produce upon request received and stop immediately after completing it.
Within Kanban, there are Kanban Card and Kanban Bin. Both of them work similarly which is to act as a signal to either request for items or send items.
Kanban Card is basically a tangible card with information such as item’s description, order date, due date, quantity, location, supplier, lead time and so forth. Manufacturer will send request for items using Kanban card to their supplier, supplier will then prepare the items based on the information on the card and send the requested items along with the Kanban card back to the manufacturer.
Similar to the Kanban Card, Kanban Bin is a tangible bin that used to store materials or items that are used for manufacturing. The Bin itself could be labeled with the name of the items or come along with a Kanban card.
Types of Bin
Let’s break this down further. There are 3 types of Kanban Bin system, single, 2-bin-system and 3-bin-system.
Single bin is where the bin itself is split into 2 levels. For example, if your first level’s materials is used up, a request for stock replenishment should be sent to the supplier and manufacturer will be continuing its production process with the second level’s materials.
2-bin-system is similar to the single bin, but using two bins instead of one. For an instance, say there is bin A and Bin B, while Bin A was sent to the supplier for stock replenishment, Bin B will be replaced while Bin A is refilling so that the manufacturing process will not be delay.
3-bin-system is using three different bins as the name itself shown. The main difference between 2 and 3-bin-system is store. Rather than the supplier sends you the materials while replenishing the first bin, the materials will be sent to you through the third bin from the stores. The second bin will be sent to the stores from the supplier. For illustration it will be first bin from manufacturer to supplier, second bin from supplier to store, and the third bin from the store back to the manufacturer.
As we continue to evolve in the digital space, E-Kanban has already been developed and have been adopted by many.
These software assist to dispose of common issues, for example, manual section mistakes and loss of cards. E-kanban frameworks can be coordinated into Enterprise Resource Planning (ERP) system, empowering ongoing interest motioning over the store network and improved perceivability. With that, you can pull information from E-kanban frameworks may be utilized to maintain stock levels by better tracking of supplier lead and refill times.
E-kanban typically uses barcode (read more here) or even QR code where it could be widely use along the processing line through simple scanning to generate signals. However, it requires internet access and might need other types of IoT to be efficient.
Note: Find out more about SmartB’s ERP system here.
There are six Kanban Rules that have been constructed by Toyota.
- Each and every demand of product, should issue production request to the manufacturer. E.g. When 10 items are bought, 10 production requests should be sent to the manufacturer.
- Production quantity should be indicated by the approaching request.
- Product should only be made or sent upon request.
- All defect product should not be send, to ensure defect-free product.
- Restricting the quantity of pending request makes the procedure progressively delicate and uncovers wasteful aspects.
- Every product produced should be attached with its request.
Advantage and Disadvantage of Kanban
There’s quite a lot to digest, so let’s summarise them a little.
|Reduces waste and scrap||An issues appear in the process of Kanban could affect the whole line|
|Provides Flexibility in production||Sudden demand rise or spike could cause significant loss.|
|Increase Output as if there are any problem faced, it could be noticed immediately and lower the amount of defective items.||It is difficult for forecasting the demand needed in the future|
|Reduce Total Cost||Requires up to date information for every Kanban|
|Improves Overall Flow||Kanban constructed could be high in complexity|
|Prevents overproduction||Tangible type of Kanban could be misplaced, damaged, or lost|
|Minimize lead time|
Implementing Kanban System
Kanban is actually versatile and doesn’t require a lot, assuming any, planning will be it. That can be both a favorable position and a drawback. It could be a favorable since it is simple to execute and doesn’t require a lot of planning to start. It could be a weakness if the idea of the task requires some degree of planning and Kanban will not be suitable.
In short, if done correctly, you’ll have lots to gain. With that, it’s importantly to note that there are few ideal environments to implement Kanban, the more you are able to fulfill the better it will be.
- Having regular amount of demand from your customer is important for avoiding stock holding. If you have to hold on to the stock it breaks the purpose of using Kanban.
- Having low variation of products will decrease the possibility of stock holding.
- Machine used should be able to perform the same task repeatedly.
- Having reliable suppliers that could always fulfill your request in time and not causing any delay in the production process.
- NOT having only one large machine that used for all kind of production. If there’s any defect on the particular machine, the whole production line will be affected. Hence, instead of having just one large machine, having multiple small sized machines could help to diversify the risk.
In addition, your workforce is one of the important key for successful Kanban implementation. After all, they are the one who will be executing these plans. They should be able to communicate well between each role, and of course having the proper knowledge to perform their assigned tasks.
Conclusion: The Adoption of Kanban
The concept of Kanban has moved beyond manufacturing. These days, other industries also apply this method especially in the digital world. Nevertheless, organizations from different scale uses Kanban to lean their business process or project to have more agility. These are commonly applied in sales, marketing, human resource, engineering project and so on. You could simply use it for business that only provides services, and required regularly from their customers.
Overall, Kanban system has been implemented in various aspect for different kind of businesses with success, and will be no exception in the future.
Last but not least, sufficient planning and preparation could avoid tragedy. Make sure to construct proper plans before execute Kanban in to your manufacturing or other business.