For an efficient implementation, the application of Just In Time is done in a methodical way.
Introduction
Just In Time requires a rigorous and methodical implementation. Below is an implementation template detailing the steps for a robust application.
1 – Choose the product or product family
The first step is to determine the product (s) we will be processing. This choice will be based on strategic criteria of the company or simply using the ABC method :
- A : 20% of articles represent 80% of volumes, sales or stock value.
- B : 30% of articles represent 15% of volume, sales, or stock value.
- C : 50% of items represent 5% of volume, sales, or inventory value.
2 – Choose the perimeter
Each improvement made to a work area will have an impact on another area of the company. For example, if we set up a Kanban on one line, this will impact the design of line edges, mizusumashi, of the warehouse, standards of supply…
Putting Just In Time in place eventually impacts the entire business. But we can not improve everything right now.
We must start with small perimeters and gradually expand it to the whole of society and then to the supplier..
To select the perimeter, we use the matrice profit/cost by measuring potential gains on inventory levels, the rate of delays…
3 – Choose the flow strategy
Depending on our market and the specificity of our products, we choose the best of 4 flow strategies. As a reminder :
- Make To Stock (MTS) : Products are made on the basis of sales forecasts.
- Assembly To Order (ATO) : the supply of the raw material is based on the forecasts, but the final assembly is started upon receipt of the sales order.
- Make To Order (MTO) : the entire value chain is driven by customer orders. Raw material is supplied according to consumption history and forecasts.
- Engineering To Order (ETO) : din this case, the products are “ custom-made “, the entire value chain only starts when the sales order is received.
3 – Set up a first level of leveling
When we want to set up Just In Time, we start with smooth a minimum production. We will have to reach a first level of leveling where the production is constant over a period of several weeks.
F. CHO Toyota’s president was saying :
“Once the level of production is more or less constant for a month, it is possible to implement systems drawn and balance the work on the chain“.
4 – Set up the tools
Depending on the chosen strategy, the workflow will not be the same. We are not going, for example, to set up Kanban for an Engineering To Order strategy.
The table below gives the tools and the order in which they will be implemented.
|
Make To Stock / Assembly To Order |
Make To Order |
Engineering To Order |
||
|
Step 1 Reduce the variability of production times |
1 |
1 |
1 |
|
|
2 |
2 |
2 |
||
|
Step 2 Redesign the workflow |
3 |
3 |
3 |
|
|
4 |
6 |
|||
|
5 |
4 |
5 |
||
|
6 |
5 |
4 |
||
|
7 |
7 |
6 |
||
|
8 |
8 |
7 |
||
|
Step 3 Set up the fired flow |
9 |
– |
– |
|
|
10 |
9 |
– |
||
|
11 |
– |
– |
||
|
12 |
10 |
– |
||
|
Step 4 Establish the total flow |
13 |
11 |
8 |
|
|
14 |
12 |
9 |
||
|
15 |
13 |
10 |
||
Source
M. Marton, I. Paulova (2006) – One piece flow
E. A. Coimbra (2009) – Total Flow Management : Achieving excellence with Kaizen and Lean Supply Chains
