Just-in-Time Management System

Introduction Phase
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Introduction Phase for Just in Time

According to Hirano, the introductory phases of JIT involves 5 steps. (14)

 

Step 1: Awareness Revolution

It means giving up old concept of managing and adopting JIT way of thinking. There are 10 principles for improvement:

1. Abolish old tradition concepts. 
2. Assume that new method will work.
3. No excuses is accepted.
4. It is not seeking for perfection, absolutely zero-defect process, few defects is acceptable.
5. Correct mistakes immediately.
6. Do not spend money on improvement.
7. Use you brain to solve problem.
8. Repeat to ask yourself 5 times before any decision.
9. Gather information from several people, more is better!
10. Remember that improvement has no limits. (Hirano, 18)

The idea of giving up old concept was especially for the large lot production, The lot production was felt that "having fewer changeover was better", but it was no longer true. Whereas JIT is a one-piece flow manufacturing. To compare the two, Hirano had this idea:

Lot production: "Unneeded goods...In unneeded quantities...At unneeded times..." (20) JIT: "Needed goods...In needed quantities...At needed times..." (21)

The main point here is to have an awareness of the need of throwing out old system and adopting a new one.

Step 2: 5S’s For Workplace Improvement (Hirano, 28-58)

 

Reference:JIT Factory Revolution P.29

The 5S’s stand for:

Seiri - Proper Arrangement
Seiton - Orderliness
Seiso - Cleanliness
Seiketsu - Cleanup
Shitsuke - Discipline

This 5S’s should be implemented company-wide and this should be part of a total improvement program.

Seiri - Proper Arrangement means sorting what you have, identifying the needs and throwing out those unnecessary.

One example is using red-tags. This is a little red-bordered paper saying what the production is, how many are accumulated and then stick these red tags onto every box of inventory . It enhances the easiness to know the inventory status and can reduce cost.

Seiton - Orderliness means making thing in order. Examples include keeping shelves in order, keeping storage areas in order, keeping workplace in order, keeping worktables in order and keeping the office in order.

Seiso - Cleanliness means having a clean workplace, equipment, etc.

Seiketsu - Cleanup mean maintaining equipment and tools.

Shitsuke - Discipline means following the rules and making them a habit.

Step 3: Flow Manufacturing (Hirano, 64-66)

 

Reference:JIT Factory Revolution P.65

Flow manufacturing means producing one single piece of product at a time but multi-handling which follows the process sequence.

There are several main points concerning flow manufacturing:

1. Arrange machines in sequence.
2. U-shaped production line (Cellular Manufacturing).

 

Reference:JIT Factory Revolution P.69

3. Produce one-piece at a time.
4. Train workers to be multi-skilled.
5. Follow the cycle time.
6. Let the workers standing and walking around while working.
7. Use small and dedicated machines.

·  Step 4: Standard Operations (Hirano, 102)

Standard Operation means to produce quality safely and less expensively through efficient rules and methods of arranging people, products and machines.

The basis of standard operations are:

1. Cycle time It means how long it would take to "carry out part all the way through the cell". (Hirano, 79) Following are the equations for calculating cycle time. (Hirano, 79)

Daily Quantity Required = Monthly Quantity Needed / Working Days per month

Cycle Time = Working Hours per day / Daily Quantity Required

2. Work sequence
3. Standard stock-on-hand
4. Use operation charts

 

Reference:JIT Factory Revolution P.104

 

Step 5: Multi-Process Handling

Multi-process handling means one worker is responsible for several processes in a cell. (Hirano, 110)

 

Some points that should be aware: (Hirano, 110)

· Clearly assign jobs to machines and workers.
· Make a good use of U-shaped cell manufacturing.
· Multi-skilled workers
· Operation should be able to perform multi-machine handling and multi process handling.

Multi-machine handling - a worker should handle several machines at once, this is also called "horizontal handling". (Hirano, 112)

Multi-process handling - a worker should handle several different processes at once, this is also called "vertical handling" and this is the basis for JIT production. (Hirano, 113)

· Uses casters extensively As author written, "Floor bolts are our enemies! Machines must be movable." (Hirano, 119)

The above 5 steps are the basis for introducing JIT. Only after these are completed can JIT be implemented.