|
Eliminate
Non-Value Added Effort Through Lean Manufacturing
By: Art Davis
Changing customer requirements are shifting many manufacturing
companies from mass production of standard products to small-lot
production of customized products, with even greater focus on
quality. Many companies continue to produce large lots
based on a forecast, with batches pushed from department to
department and with people trained in limited, repetitive tasks.
But it's becoming clear that this approach causes excessive
inventory, too much movement and waiting and wasted resources in
people; plant and equipment, all of which result in highly
inflated costs.
Lean manufacturing
is a systematic approach to identifying and
eliminating waste (non-value added activities) through
continuous improvement to allow product flow at the pull of the
customer in pursuit of perfection. It focuses on eliminating
non-value added activities from your company's processes while
streamlining value-added activities. A people-oriented approach
that empowers a team to take action to achieve improvements,
lean is the best way to effectively use a company's most
valuable resource — its people. Any activity that doesn't add to
the market form or function of the product (things for which the
customer is willing to pay) is a non-value added activity, or
the "wastes" that lean seeks to eliminate. Interestingly, many
manufacturers don't even recognize some of these as "wastes,"
but simply necessary evils of doing business.
Lean manufacturing focuses on eight specific major wastes:
1. Overproduction
This is probably the most deceptive waste. It simply is making
more products earlier and faster than the next process requires.
In all cases, overproduction leads to unneeded inventory.
Overproduction usually is deliberate to cover up quality
deficiencies, equipment breakdowns, and inadequate employee
training, long process setup and unbalanced workload.
2. Inventory
This waste is any supply in excess of a one-piece flow through
the process, including work in process and finished goods.
Holding inventory costs money — roughly 25 percent of the value
of the inventory if held for a year.
3. Defects
This is a major waste that includes material, labor, machine
hours, inspecting, sorting or rework. Its causes can be
inadequate training, weak process control, deficient maintenance
and/or incomplete engineering specifications.
4. Processing
This waste is effort that adds no value from the customer's
viewpoint. It can include extra or incorrect inspections, extra
copies of paperwork and over or redundant processing
"just-in-case." Expediting processing because of failing to meet
schedule also is a waste.
5. Transportation
Moving materials in the manufacturing process can add costs, but
no value. Not only does the act of transporting add to costs, it
also typically involves using expensive equipment. Further costs
are space, racking and the people and systems needed to
track the material.
6. Waiting
This includes all idle time, such as waiting
for parts from up-stream operations and waiting for tooling,
set-ups and instructions. Waiting for workers generally is of
greater concern than machine use.
7. Motion
Any people and/or machine activity that doesn't add value to the
product is considered waste. Its symptoms include time looking
for tools, extra product handling, walking and product
arrangement, stacking, etc. Causes include poor plant layout and
workplace design, inadequate training, weak processing and
constant schedule changes to reduce on-time delivery problems.
8. People
Factors such as company culture, hiring practices, management
styles, turnover rates and morale all contribute to this waste —
not using your employees' abilities to their fullest potential.
Do A Self-Assessment
The best way to get started down the road to becoming lean is
doing a simple "self-assessment" walk. Go to the shop floor, the
engineering area, the production control and order management
department and pick a product family from the customer end of
the value stream. Consider these as opportunities — long lead
times, frequent set-ups, long set-ups, significant
work-in-progress dollars, critical work centers, flow
bottlenecks, capacity constraints, key customers, large
inventories and competitive products.
Look for products that
pass through similar processing steps, and over common
equipment, in your downstream processes. Selecting the product
family based on upstream fabrication steps that serve many
product lines in a batch mode won't give you what you need.
Once
you've picked a product family, put yourself in your customers'
position and trace the design, order and physical product from
launch
back to original concept, from delivery back to the sale and
from finished product back to raw materials. Include distances,
stops and their duration, and the number of functions handling
the product or its components.
Ask yourself these questions:
- Does this product provide the precise value sought by
the customer?
- Do the design, order and product flow continuously
through the necessary activities to reach your customers?
- Can your customers pull the product from the value
stream, i.e., can they get just what they want, when they
want it and without your company holding a mountain of
finished goods "just in case?"
- Is the value stream's performance steadily improving?
- Can your plant's overall lead-time be measured in hours
instead of days or weeks?
If your answer to each of these questions is yes, then you
don't need to think further about lean enterprise — you're lean
already. If you still aren't getting an adequate return on
assets or sales, the problem must lie elsewhere, such as
structural problems in your industry, slipping customer need for
your category of products, etc.
But if your answer to most of these questions was no, it's time
to think about getting lean.
Lean manufacturing as a form of continuous improvement isn't a
destination, but rather a journey; an ongoing process. So the
first step to getting lean is to learn as much as you can about
lean manufacturing through examples of other companies and
existing literature.
By identifying various types of waste in your operation,
determine each waste's root causes and lead your team in a
systematic lean manufacturing approach to removing the wastes.
Typical improvement projects supporting lean might include:
- Value stream mapping
- Flow/cellular manufacturing
- Visual controls and work place organization (5S
concepts)
- Standardized operations
- Pull/Kanban production methods
- Set-up reduction
- Total preventive maintenance
- Mistake-proofing
- Plant layout
- Kaizen event facilitation
Effective implementation of lean manufacturing techniques can
generate significant benefits:
- Reduce work in process up to 90%
- Reduce lead time up to 95%
- Improve productivity 10-40%
- Improve quality 25-75%
- Enhance teamwork and communication
- Multiple other benefits related to improved product flow
Art Davis
Principal
The Davis Group
About the Author

Art Davis is principal of The Davis Group, a Chicago area
consultancy specializing in business process improvement and
total quality. He has delivered many training programs in Six
Sigma for Motorola, Caterpillar, ITW, Litelfuse and other firms.
For more information call: 800-959-0632.
Comment on this article
 |