Chapter 14 Just In Time Systems. Final Exam . A total of 33 questions. Chapter 11 Chapter 12 Chapter 13 Chapter 14 ( 3 blank filling qualitative questions) 30 quantitative multiple choice questions on Ch 11, 12, 13. Just In Time (JIT).
Just In Time
handling costs, extra WIP
requires space--no value added
of equipment and manpower, scrap
Suppose the only difference between two parts is an extra
operation on one of them. Postpone this operation as much as you can. Then up to the last minute you have a standard part that can serve two different purposes
Since there is only a small inventory, production
must cease until the problem is fixed
Therefore low quality has
extreme high cost of No Production.
The ideal lot size in JIT is 1. But usually it is not technically and economically possible. The goal is to have small lots. Small batches at each run.
Benefits of small lot sizes
Less inventory ==> less carrying costs, less space
When there is quality problem, it hits a small number of parts ==> less rework
Flexibility : we can easily switch from one product to another and fulfill customer orders. Example; Suppose 50% of our production time is devoted to product A,25% to B and 25% to C.
In conventional system we may produce product A for 6 months, then switch to B for 3 months and then to C.
In JIT, we may produce A for 4 hours, then B for 2 hours, then C. A lot of flexibility and quick response to any change in customer demand.
We can not achieve this flexibility, if we do not have short setup and changeover time.
identify tractable costs and assign
them to specific activities
level capacity loading; rate based production schedule
Production based on forecast
Production based on customer orders
First Tier Supplier
Second Tier Supplier
Third Tier Supplier
Some companies prefer to work with local suppliers.
Vendor Score Sheet
Periodic audit of suppliers to ensure of supplier performance, quality and delivery.If audit reveals problem areas, the buyer can address these, before they result in a serious problem.
Factors typically covered in supplier audit
A detailed examination of the policies and capabilities of a supplier.
Verifies whether the supplier meets or exceeds the requirements of the buyer.
This is particularly important when the buyer is seeking to establish long term relationships with the supplier.
Certified suppliers are also referred to as world class suppliers.
When a supplier is certified, much or all of the inspections are eliminated.
Aspect Partner Adversary
# of suppliers one or few many; playoff one against the other
Length of long term may be brief
Low price moderately major consideration
Reliability high may not be high
Openness high low
Quality at source inspection
Volume of high may be low due to many
Location proximity is stressed widely dispersed
for short lead time
Flexibility relatively high relatively low
and lead times
Make the system flexible
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