This file introduces the principle of Kanban and pull system. In the rest of the file, we concentrate on Kanban and introduce the types of Kanban, six rules for an effective kanban system, the number of Kanban card and kanban circulation.
2. This file introduces the principle of Kanban and pull system. In the rest of the file, we
concentrate on Kanban and introduce the types of Kanban, six rules for an effective kanban
system, the number of Kanban card and kanban circulation.
About this file
3. Lean manufacturing
One of the important concepts in lean manufacturing and kaizen philosophy
is just in time (JIT) manufacturing.
In fact one of the pillar of lean manufacturing is JIT.
4. Lean manufacturing
lean manufacturing has focused on muda (waste).
As you can see in the following picture, there are seven types of waste.
5. Lean manufacturing
One of the types of waste is over-production. over-production is the worst type
of waste.
6. Pull system Vs. push system
The push system involves forecasting inventory needs to meet customer demand.
In fact the workstations complete that parts which are delivered from previous
workstation.
7. Pull system Vs. push system
Disadvantages of the push system
forecasts are often inaccurate as sales can be unpredictable and vary from one
year to the next.
Another problem with push inventory control systems is that if too much
product is left in inventory. This increases the company's costs for storing these
goods.
Advantage to the push system
the company is fairly assured it will have enough product on hand to complete
customer orders.
8. Pull system Vs. push system
The pull system begins with a customer's order. With this strategy, companies only
make enough product to fulfill customer's orders.
Advantage to the push system
there will be no excess of inventory that needs to be stored, thus reducing inventory
levels and the cost of carrying and storing goods.
Disadvantages of the push system
it is highly possible to run into ordering dilemmas, such as a supplier not being able
to get a shipment out on time. This leaves the company unable to fulfill the order and
contributes to customer dissatisfaction.
9. JIT
• JIT reduces the inventory level. In fact this inventory level is like a buffer against
Fluctuations in demand and problem for our system.
• Following Problems will be revealed With inventory reduction.
10. Kanban
• Kanban is a scheduling system for lean manufacturing and just-in-time manufacturing (JIT).
看板
Signboard
• Kanban is one method to achieve JIT.
• Kanban is a visual control system that provides some information about the raw materials,
finish product and etc .
11. Kanban
Is kanban suitable for all facturies?
• Kanban is suitable for factories with low fluctuations in demand.
• In fact, Kanban is not suitable for factories with high
fluctuations in demand or factories that manufacture
Seasonal products.
12. Kanban
Types of Kanbans
The two most common types of Kanbans used are:
1. Withdrawal (Conveyance) Kanban :
Specifies the number of pieces downstream process should withdraw from the upstream
Processes.
2. Production Kanban :
allow to upstream process to produce.
13. Kanban
six rules for an effective kanban system
Customer (downstream) processes withdraw items in the precise amounts specified by the Kanban.
Supplier (upstream) produces items in the precise amounts and sequences specified by the
Kanban.
No items are made or moved without a Kanban.
A Kanban should accompany each item, every time.
Defects and incorrect amounts are never sent to the next downstream process.
The number of Kanbans is reduced carefully to lower inventories and to reveal problems
14. Kanban
How many Kanban cards are needed?
N=
𝐷𝑇(1+𝑥)
𝐶
Where,
Y: number of cards
D: demand per unit of time
T: lead time
C: container capacity
X: buffer, or safety factor
suppose that hourly demand was 200 unit
s, lead time was 12 hours, and the container capacity
was 144 units. Assume that there was variation in le
ad time or demand, then we can set the safety factor
to 15%:
N=
200∗12(1+0.15)
144
=20
15. kanban
Some terms
Water beetle: are an operators that convey Kanban cards and pallets between workstation.
Kanban station: is a place for putting Kanban cards.
16. Kanban
kanbancirculation
1
• When the downstream process uses all parts, he/she puts the Withdrawal kanban cards into
Withdrawal Kanban stations.
2
• Water beetle takes withdrawal kanban from Kanban station and convey that to upstream
process.
3
•Water beetle separates production kanban from the parts in the pallet and put in the Kanban
station and attach withdrawal Kanban to the pallet then carries the pallet to downstream process.
4
• Upstream process uses the production Kanban in the Kanban station as a
production order.
5
• Empty pallets should be placed in the certain places.
6
• upstream process should places the parts in the certain places.
