Lean manufacturing
- TAKT time
Lean manufacturing systems work on a rhythm.
Whole organization works on the rhythm provided by the customer.
This rhythm is known as the TAKT time of the system. This is the
ultimate pull scheduling
system anyone can think about.
The TAKT Time can be calculated using simple
formula given below.
TAKT
time = Net Time Available for production / Customer Demand |
For an example think you work 8 hrs a day for
5 days a week. For a week you have a demand of 100Pcs. Then your
calculation will be as follows.
Takt = 8 x 5 x 60 minutes
/ 100 Pcs
= 24 minutes
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What is the meaning of this? This means that
you have to produce a finished product in every 24th minute. No
this does not mean that you should produce 2Pcs in every 48 Minutes.
It doesn’t mean that the system should produce an item in
less than 24 minutes. Both these scenarios can lead to inefficiencies
and wastes in the system.
If we aim to produce 20Pcs a day we have no need
to produce an item in every 24th minute. In this case system may
not run smoothly. For an example it might produce 12Pcs in first
7 hours and the remaining 8Pcs in the last hour (of cause if they
have enough capacity). This is not the aim of a lean manufacturing
system. So you can understand that not only the work, but also
the way the work is carried out is important in lean manufacturing
context.
If we produce a piece of that particular product
in 20 minutes what will be the end result. You will either produce
quantities greater than required or you might have an idle time.
Over production and waiting are wastes in lean manufacturing.
Both will lead to higher WIP accumulation and related problems.
I believe the greatest problem of implementing
this kind of manufacturing concept is the mentality of the people.
If you tell your finance guys “I worked on takt principle
and I produced a part in every 24th minute, although I could have
produced a piece in 20 minutes” I am sure that guy will
go mad. Only very little number of people understand that we should
only produce to the customer demand not extra.
So what are the advantages of sticking to the
takt time?
1. It will give you the rhythm in which the system
should operate
2. Production is smoothly planned and operations will be carried
out without interruptions
3. The system is in synchronization with customer requirement
4. Pull scheduling is enabled
5. No over production
6. No rush hours in work
7. WIP reduced and problems in the system will be reveled
Takt time principle will work very well in cases
where the demand can be traced easily. In a system where there
is a fluctuating demand the takt will change continuously on the
customer demand.
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