The Toyota Production System (TPS), originally called as Just-in-Time (JIT) production system, was developed by Taiichi Ohno (Chief Engineer at Toyota) after World War II to make the system effective and efficient enough to meet the customer’s requirements satisfactorily.
Kaizen and Kanban are the two different terms used in the TPS. Both the terms are used interchangeably yet have a distinct meaning.
In this article, we will discuss these two terms individually and will try to find out the differences. Ok
Kaizen is originated from two Japanese words Kai and Zen. Kai means change and Zen means Good. Thus the literal meaning of Kaizen is Change for Good or Continuous Improvement.
Kaizen, a part of TPS, is being practised all over the industries with a common objective of continuous improvement.
The major questions are How does Kaizen works? and How to implement it?
The common answer to all the questions related to the Kaizen is the PDCA Cycle. Sometimes also known as OPDEACycle where O stands for Observation.
Now, What is this PDCA Cycle ???
A PDCA Cycle consists of the four steps which are sequenced logically.
These four steps are:-
Let’s check out these four steps individually.
Step 1. Plan
In this step, one has to define its objectives and plan the activities to achieve those objectives.
Step 2. Do
The second step is all about the actual implementation of the planned activities. Any changes required to ensure the implementation of these activities could be made.
Step 3. Check
In this step, the actual results are properly evaluated (comparison between actual and targeted results) and the errors (if any) are identified. Further opportunities for improvement are also identified.
Step 4. Act
This step is meant to inculcate all the changes, identified in the previous step, in the planning step.
The successful implementation of Kaizen through the PDCA cycle offers various advantages. Some of them are as:-
- Improved Productivity
- Improved Product Quality
- Enhanced Process Capabilities
- Reduction in Waste
- Increased Profitability and many more.
Kanban is a Japanese word that means Signboard/billboard.
Kanban system, sometimes, also known as a workflow management system or scheduling system or inventory control system.
In manufacturing, the Kanban system is used as a method to achieve the JIT production system. To understand the Kanban system, we must acquire knowledge about the JIT production system.
A JIT production system works on the manufacturing on demand. It means a JIT system maintains almost zero inventory in its pocket. That’s how JIT philosophy work to eliminate the inventory cost and delay caused by inventory.
The main objectives behind the use of Kanban System are:-
- To reduce the inventory waste
- To reduce the non-productive time
How a Kanban system work???
The working of Kanban System starts from putting the limit on the storage of any form of inventory like raw materials, work in process, final product, etc. If inventories go down below these limits, immediate information is sent to the concerned authorities to take appropriate action. The same thing happens in the case of inventories go up these limits.
Earlier the mode of communication was through Cards (that’s why it is known as kanban system) but the nowadays electronic medium is being used for this purpose.
The Kanban system mainly deals with two types of periods.
- Lead Time
- Cycle Time
Lead time is the duration of the period that starts from receiving the order and deliver the product to the customer. Whereas Cycle time is the duration of the period from work start on the product to the delivery of the product to the customer.
Hence, Somehow Lead time is always greater than the cycle time as it also includes the waiting time.
Lead Time > Cycle Time
Advantages of Kanban
The main benefits, a Kanban system offer, are:-
- Reduced inventory cost which further reduces the Product Cost.
- Reduction in the lead time.
To meet the customers’ demand timely and to control the inventory cost, Kaizen & Kanban are the two important weapons in the hand of manufacturers.