Lean Manufacturing is the term our country uses to describe the Toyota
Production System (TPS). Thousands of U.S. executives, engineers, and
manufacturing technicians have traveled to Japan to visit Toyota to learn how to
achieve very high quality while maintaining competitive prices and a very well
andon - a system of flashing lights used to indicate production status
in one or more work centers; the number of lights and their possible colors
can vary, even by work center within a plant; however, the traditional colors
and their meanings are:
green - no problems
autonomation - in Toyota parlance, automation with a human touch;
English translation of jidoka.
yellow - situation requires attention
red - production stopped; attention urgently needed
baka-yoke - a manufacturing technique of preventing mistakes
(error-proofing) by designing the manufacturing process, equipment, and tools
so that an operation literally cannot be performed incorrectly; an attempt to
perform incorrectly, as well as being prevented, is usually met with a warning
signal of some sort; the term poka-yoke is sometimes referred to as a
system where only a warning is provided.
cellular manufacturing - an approach in which manufacturing work
centers [cells] have the total capabilities needed to produce an item or group
of similar items; contrasts to setting up work centers on the basis of similar
equipment or capabilities, in which case items must move among multiple work
centers before they are completed; the term group technology is sometimes used
to distinguish cells that produce a relatively large family [group] of similar
cycle time - the normal time to complete an operation on a product.
This in NOT the same as takt time, which is the allowable time to
produce one product at the rate customers are demanding it.
error-proofing - a manufacturing technique of preventing mistakes (baka-yoke)
by designing the manufacturing process, equipment, and tools so that an
operation literally cannot be performed incorrectly; an attempt to perform
incorrectly, as well as being prevented, is usually met with a warning signal
of some sort; the term poka-yoke is sometimes referred to as a system
where only a warning is provided.
flexible manufacturing system - an integrated manufacturing capability
to produce small numbers of a great variety of items at low unit cost; an FMS
is also characterized by low changeover time and rapid response time.
heijunka - A production scheduling/leveling tool, essentially to
distribute kanban cards in an efficient manner.
jidoka - a Japanese word which translates as autonomation; a form of
automation in which machinery automatically inspects each item after producing
it, ceasing production and notifying humans if a defect is detected; Toyota
expands the meaning of jidoka to include the responsibility of all workers to
function similarly, i.e. to check every item produced and to make no more if a
defect is detected, until the cause of the defect has been identified and
jishu kanri - self-management, or voluntary participation.
just-in-time - a production scheduling concept that calls for any item
needed at a production operation - whether raw material, finished item, or
anything in between, to be produced and available precisely when needed,
neither a moment earlier nor a moment later.
jutsu - to talk, or ‘the art of’ (i.e., 'leanjutsu: the art of lean
kaikaku - A rapid and radical change process, sometimes used as a
precursor to kaizen activities.
kaizen - the philosophy of continual improvement, that every process
can and should be continually evaluated and improved in terms of time
required, resources used, resultant quality, and other aspects relevant to the
kanban - a card or sheet used to authorize production or movement of an
item; when fully implemented, kanban (the plural is the same as the singular)
operates according to the following rules:
- All production and movement of parts and material take place only as
required by a downstream operation, i.e. all manufacturing and procurement
are ultimately driven by the requirements of final assembly or the
- The specific tool which authorizes production or movement is called a kanban.
The word literally means card or sign, but it can legitimately refer to a
container or other authorizing device. Kanban have various formats
and content as appropriate for their usage; for example, a kanban
for a vendor is different than a kanban for an internal machining
- The quantity authorized per individual kanban is minimal, ideally
one. The number of circulating or available kanban for an item is
determined by the demand rate for the item and the time required to
produce or acquire more. This number generally is established and remains
unchanged unless demand or other circumstances are altered dramatically;
in this way inventory is kept under control while production is forced to
keep pace with shipment volume. A routine exception to this rule is that
managers and workers are continually exhorted to improve their processes
and thereby reduce the number of kanban required.
karoshi - death from overwork.
lean manufacturing or lean production - the philosophy of
continually reducing waste in all areas and in all forms; an English phrase
coined to summarize Japanese manufacturing techniques (specifically, the
Toyota Production System).
line balancing - equalizing cycle times [productive capacity,
assuming 100% capacity utilization] for relatively small units of the
manufacturing process, through proper assignment of workers and machines;
ensures smooth production flow. [Back
mixed-model production - capability to produce a variety of models,
that in fact differ in labor and material content, on the same production
line; allows for efficient utilization of resources while providing rapid
response to marketplace demands.
mizusumashi - the classic 'water spider', who performs a wide range of
tasks which allow workers to perform 'value-added' tasks.
mokeru - the Japanese term for the industrial engineering, more
properly translated as ‘profit-making I.E.’.
muda (waste) - activities and results to be eliminated; within
manufacturing, categories of waste, according to Shigeo Shingo, include:
- Excess production and early production
- Movement and transport
- Poor process design
- Inefficient performance of a process
- Making defective items
mura - inconsistency
muri - unreasonablness
nagara - smooth production flow, ideally one piece at a time,
characterized by synchronization [balancing] of production processes and
maximum utilization of available time, including overlapping of operations
ninjutsu - the art of invisibility (applies to management)
poka-yoke - a means of providing a visual or other signal as to the
location or condition of a part characteristic. Often referred to as
'error-proofing', poke-yoke is actually the first step in truly error-proofing
a system (see baka-yoke).
pull system - a manufacturing planning system based on communication of
actual real-time needs from downstream operations ultimately final assembly or
the equivalent - as opposed to a push system which schedules upstream
operations according to theoretical downstream results based on a plan which
may not be current.
5S - refers to the five words seiri, seiton, seison,
seiketsu, shitsuke. These words are shorthand expressions for
principles of maintaining an effective, efficient workplace
(Like many concepts, the 5S can be interpreted narrowly or broadly,
depending on circumstances of their use.)
- seiri - eliminating everything not required for the work being
- seiton - efficient placement and arrangement of equipment and
- seison - tidiness and cleanliness
- seiketsu - ongoing, standardized, continually improving seiri,
- shitsuke - discipline with leadership
seiban - Seiban is the name of a Japanese management practice taken
from the Japanese words "sei", which means manufacturing, and
"ban", which means number. A Seiban number is assigned to all parts,
materials, and purchase orders associated with a particular customer job, or
with a project, or anything else. This enables a manufacturer to track
everything related with a particular product, project, or customer. It also
facilitates setting aside inventory for specific projects or priorities. That
makes it great for project and build-to-order manufacturing.
sensei - one who provides information; a teacher, instructor, or rabbi.
setup time - work required to change over a machine or process from one
item or operation to the next item or operation; can be divided into two
- internal: setup work that can be done only when the machine or
process is not actively engaged in production; OR
- external: setup work that can be done concurrently with the
machine or process performing production duties.
saki - a rice wine, preferrably served warmed.
shojinka - continually optimizing the number of workers in a work
center to meet the type and volume of demand imposed on the work center;
shojinka requires workers trained in multiple disciplines; work center layout,
such as U-shaped or circular, that supports a variable number of workers
performing the tasks in the layout; the capability to vary the manufacturing
process as appropriate to fit the demand profile.
SMED - abbreviation for Single Minute Exchange of Die; literally,
changing a die on a forming or stamping machine in a minute or less; broadly,
the ability to perform any setup activity in a minute or less of machine or
process downtime; the key to doing this is frequently the capability to
convert internal setup time to external setup time; variations on SMED
sushi - raw fish, particularly good for your health and heart, and
available in wide variety.
- Single-digit setup: performing a setup activity in a single-digit
number of minutes, i.e. fewer than ten.
- OTED: One touch exchange of die; literally, changing a die with
one physical motion such as pushing a button; broadly, an extremely simple
procedure for performing a setup activity.
takt time - takt, is a German term for rhythm. Takt time is the
allowable time to produce one product at the rate customers are demanding it.
This is NOT the same as cycle time, which is the normal time to complete an
operation on a product (which should be less than or equal to takt
teian - a proposal, proposition, or suggestion. A teian system
can be likened to a system which allows and encourages workers to actively
propose process and product improvements.
Toyota - changed from the true form, Toyoda, meaning abundant
rice field, by the Toyota marketing department. Toyoda is the family name of
the founders of the Toyota Motor Company.
water spider - one who performs a wide range of tasks which allow
workers to perform 'value-added' tasks.
WCM - world class manufacturing is the philosophy of being the best,
the fastest, and the lowest cost producer of a product or service. It implies
the constant improvement of products , processes, and services to remain an
industry leader and provide the best choice for customers, regardless of where
they are in the process.