The
Kanban
& Supermarket Sizing
form answers the following questions.
- How much inventory should be
maintained at a process?
- How many kanbans should be
used?
- What size should the kanbans
be?
How-to
Single Unit
is the most common and traditional kanban system.
- From
Kanban Type,
choose the type of kanban.
- Single Unit
- Each container of a fixed size has a kanban. When the container
is removed from the supermarket, the kanban is removed and returned to the
supplier operation to signal the need to produce an additional kanban quantity.
This the most common and traditional kanban system.
- Two Bin
- Two bins, or containers, are used. Each container of a fixed size
contains a quantity equal to the production demand rate multiplied by the
replenishment time. When a container is empty, it is returned to the supplier
operation to signal the need to replenish it.
Note
Because there are only two containers in this system, the
maximum inventory is twice the container quantity.
- Multi-bin
- This is similar to the two bin system because reordering is based
on a certain level of inventory, instead of individual container kanban.
However, unlike the two bin system, containers can be of any constant size
smaller than the reorder quantity. The reorder point specifies the number of
containers to reorder.
- Enter the following data.
-
Demand Rate (units
per):
Rate at which inventory is consumed.
- Replenishment Time:
The time required to restock a bin, or container, once the request is made.
-
Safety Stock (%):
The percent of inventory that exists to protect against downtime.
- For
Single Unit
and
Multi-bin,
enter the container size.
- Add any action items or
comments.
For more information, go to
Add and complete a form.
Calculations
- Calculations for the
Single Unit
kanbans.
- Supermarket Size (units)
- Supermarket Size (units) = Demand Rate * Replenishment Time * (1
+ Safety Stock)
Units are rounded up to the next integer.
- Supermarket Size (containers)
- Supermarket Size (containers) = Supermarket Size (units) /
Container Size (units)
Containers are rounded up to the next integer.
- Number of kanban cards in supermarket
- Number of kanban cards in supermarket = Supermarket Size
(containers)
- Calculations for the
Two Bin
kanbans.
- Number of units in bin
- Number of units in bin = Demand Rate * Replenishment Time * (1 +
Safety Stock)
Units are rounded up to the next integer.
- Number of bins
- Number of bins = 2
- Total number of units in supermarket
- Total number of units in supermarket = 2 * (Number of units in
bin)
- Calculations for the
Multi-bin
kanbans.
- Trigger Point (units)
- Trigger Point (units) = Demand Rate * Replenishment Time * (1 +
Safety Stock)
Units are rounded up to the next integer.
- Trigger Point (containers)
- Trigger Point (containers) = Supermarket Size (units) / Container
Size (units)
Containers are rounded up to the next integer.
- Total number of containers in supermarket
- Total number of containers in supermarket = 2 * Trigger Point
(containers)