Lean manufacturing, mind tools

Lean Manufacturing
Working More Efficiently
Cut waste, increase quality and add value.
© iStockphoto/fotomy
How much waste does your organization
produce?
For example, do you ever have to wait for
someone else to finish a task before you can
get on with your own work? Do you have a
large inventory of unsold stock? Do you have
more workstations that you need? Or do you
order materials months in advance of when
they are needed?
How about flexibility? If consumers want a
modification to your product, can you quickly
change your processes to meet their needs?
Waste costs you and your customers money.
And if your customers have to pay more
because of it, they might go elsewhere. Being
competitive also requires a lot of flexibility.
You must be able to meet the changing
demands of your customers quickly and
effectively, and adapt to a rapidly changing
business environment.
So, how can you reduce waste and do things
more efficiently? And how can you keep up
with the changing demands of consumers?
First mentioned in James Womack's 1990 book,
"The Machine That Changed the World," lean
manufacturing is a theory that can help you
to simplify and organize your working
environment so that you can reduce waste,
and keep your people, equipment, and
workspace responsive to what's needed right
now.
Tip:
The idea of lean manufacturing is just as
applicable to offices and other work
environments as it is to manufacturing plants.
It's helpful to relate words like "inventory,"
"customers," and "production" to whatever
you're processing - data, documents,
knowledge, services, and so on.
A Brief History of Lean Manufacturing
Henry Ford was one of the first people to
develop the ideas behind lean manufacturing.
He used the idea of "continuous flow" on the
assembly line for his Model T automobile,
where he kept production standards extremely
tight, so each stage of the process fitted
together with each other stage, perfectly. This
resulted in little waste.
But Ford's process wasn't flexible. His
assembly lines produced the same thing, again
and again, and the process didn't easily allow
for any modifications or changes to the end
product – a Model T assembly line produced
only the Model T. It was also a "push" process,
where Ford set the level of production, instead
of a "pull" process led by consumer demand.
This led to large inventories of unsold
automobiles, ultimately resulting in lots of
wasted money.
Other manufacturers began to use Ford's
ideas, but many realized that the inflexibility
of his system was a problem. Taiichi Ohno of
Toyota then developed the Toyota Production
System (TPS), which used Just In Time
manufacturing methods to increase efficiency.
As Womack reported in his book, Toyota used
this process successfully and, as a result,
eventually emerged as one the most profitable
manufacturing companies in the world.
Lean Manufacturing Basics
Lean manufacturing is based on finding
efficiencies and removing wasteful steps that
don't add value to the end product. There's no
need to reduce quality with lean
manufacturing – the cuts are a result of
finding better, more efficient ways of
accomplishing the same tasks.
To find the efficiencies, lean manufacturing
adopts a customer-value focus, asking "What
is the customer willing to pay for?" Customers
want value, and they'll pay only if you can
meet their needs. They shouldn't pay for
defects, or for the extra cost of having large
inventories. In other words, they shouldn't pay
for your waste.
Waste is anything that doesn't add value to
the end product. In lean manufacturing, there
are eight categories of waste that you should
monitor:
1. Overproduction – Are you producing
more than consumers demand?
2. Waiting – How much lag time is there
between production steps?
3. Inventory (work in progress) – Are your
supply levels and work in progress
inventories too high?
4. Transportation – Do you move materials
efficiently?
5. Over-processing – Do you work on the
product too many times, or otherwise
work inefficiently?
6. Motion – Do people and equipment
move between tasks efficiently?
7. Defects – How much time do you spend
finding and fixing production mistakes?
8. Workforce – Do you use workers
efficiently?
Note:
The first seven sources of waste were
originally outlined in the Toyota production
system, and were called "muda." Lean
manufacturing often adds the eighth
"workforce" category.
Lean manufacturing gives priority to simple,
small, and continuous improvement such as
changing the placement of a tool, or putting
two workstations closer together. As these
small improvements are added together, they
can lead to a higher level of efficiency
throughout the whole system. (Note that this
emphasis on small improvements doesn't
mean that you cannot make larger
improvements if they are required!)
Note:
Although the aim of lean manufacturing is to
remove as much waste as possible by
continuously refining your processes, you
probably won't eliminate waste completely.
Lean Manufacturing Process
The lean manufacturing process has three key
stages:
Stage 1 – Identify waste
According to the lean manufacturing
philosophy, waste always exists, and no
matter how good your process is right now, it
can always be better. Lean manufacturing
relies on this fundamental philosophy of
continuous improvement, known as Kaizen.
One of the key tools used to find this waste is
a Value Stream Map (VSM). This shows how
materials and processes flow through your
organization to bring your product or service
to the consumer. It looks at how actions and
departments are connected, and it highlights
the waste. As you analyze the VSM, you'll see
the processes that add value and those that
don't. You can then create a "future state"
VSM that includes as few non-value-adding
activities as possible.
Stage 2 – Analyze the waste, and find the
root cause
For each waste you identified in the first
stage, figure out what's causing it by using
Root Cause Analysis. If a machine is
constantly breaking down, you might think the
problem is mechanical and decide to purchase
a new machine. But Root Cause Analysis could
show that the real problem is poorly trained
operators who don't use the machine properly.
Other effective tools for finding a root cause
include Brainstorming and Cause and Effect
Diagrams.
Stage 3 – Solve the root cause, and repeat
the cycle
Using an appropriate problem-solving
process, decide what you must do to fix the
issue to create more efficiency.
Tools to Reduce Waste
Once you have identified wastes using the
three key stages above, you can then apply
this next set of tools to help you reduce waste
further:
Just in Time – This is the core idea of lean
manufacturing and is based on the "pull"
model. To minimize stock and resources,
you only purchase materials, and produce
and distribute products when required. You
also produce small, continuous batches of
products to help production run smoothly
and efficiently. By reducing batch size, you
can also monitor quality and correct any
defects as you go. This reduces the
likelihood of quality being poor in future
batches.
(In manufacturing, a key way of doing this
is to use Kanban, below.)
Kanban – This is one of the key ways to
involve people in the lean manufacturing
process. Here, you support the Just In Time
model by developing cues in the system to
signal that you need to replace, order, or
locate something. The focus is on reducing
overproduction, so that you have what you
need, only when you need it.
Zero Defects – This system focuses on
getting the product right the first time,
rather than spending extra time and money
fixing poor-quality products. By using the
Zero Defects system, you'll reinforce the
notion that no defect is acceptable, and
encourage people to do things right the
first time that they do something.
Single Minute Exchange of Die (SMED) –
This helps you build flexibility into your
production. For example, in the automotive
industry, it could take days to change a line
to produce a different car model. With
SMED, the assembly process and machinery
are designed to support quick and efficient
changeovers. (Here, a "die" is a tool used
to shape an object or material.)
The 5S Philosophy – Lean manufacturing
depends on standardization. You want your
tools, processes, and workplace
arrangements to be as simple and as
standard as possible. This creates fewer
places for things to go wrong, and reduces
the inventory of replacement parts that you
need to hold. To accomplish a good level of
standardization, use the 5S System.
Tip:
These techniques offer proven solutions for
fixing waste within your organization.
However, remember first to apply the three-
stage lean manufacturing process, and to deal
with any issues that this raises.
Key Points
Lean manufacturing focuses on optimizing
your processes and eliminating waste. This
helps you cut costs and deliver what the
customer wants and is willing to pay for.
With a lean philosophy, you enjoy the benefit
of continuous improvement. So, rather than
making rapid, irregular changes that are
disruptive to the workplace, you make small
and sustainable changes that the people who
actually work with the processes, equipment,
and materials will take forward.
This systematic and simple approach is very
effective across all types of industries. What's
more, ultimately, a process without waste is
much more sustainable.
Apply This to Your Life
1. Overproduction – Do you provide more
data or information than is needed? Do
you create reports more often than
required for example? Or do you spend
unnecessary amounts of time formatting
these reports?
2. Waiting – Do you spend too much time
waiting for information or data from
others, before you can do your work?
What can you do about this?
3. Inventory (work in progress) – Do you
have a large stock of materials? Are your
supply levels and work-in-process
inventory too high?
4. Transportation – Do things flow
efficiently? Could you combine deliveries,
or deliver things more quickly?
5. Overprocessing – Do you needlessly
work on something more than once?
6. Motion – How is work passed along in
your team? Do people understand what
they're required to do at each step? Do
people and equipment move between
tasks efficiently?
7. Defects – How often do you find
mistakes? Do you make the same
mistakes on a regular basis?
8. Workforce – Do you use your time
wisely? Do you spend most of your time
on activities that add value and are a
high priority?
This is just one of hundreds of skill-building
tools and resources on this site. Click here for
more articles, subscrib