How
is quality achieved? ( Top down approach)
A lot people thought that quality is achieved thru
inspection and this is not true at all. As stated earlier in “who owns quality” section, quality can only be attained through design of the product with the customer in mind and manufacturing product with all correct control of process input such as operator, equipment, method and material which impact
product quality . An example of correct control of process
would be if a machine is needed to cut a product to specific size, then machine parameter such as type of
cutting knife and cutting distance and
pressure must be set to get all parts
being cut clean (no burrs) and to customer specific size. The cutting process must done by properly
trained operator with step by step documented work instruction for the operator to
follow. Then it will follow with proper
testing and inspection to check the product quality.
There are 3 types of approach to accomplish a quality
product :-
Type
|
Method adopted
|
Best
-1
|
Quality is attain
through design, planning and build into the product.
|
Good
-2
|
Some deficiencies
in design and manufacturing of product,
there are quality improvement to address the deficiencies through
corrective and preventive action
|
Average
- 3
|
Ignorant of the
design and plan quality into product, lack of quality improvement activities
only continue to inspect and test to screen product meet customer requirement and defective parts
|
Quality is achieved by design and building quality into the
product and NOT thru inspection.
Inspection is conducted on finished or semi finished product to screen
out defect and compliance part. It is
too late for any real action to correct
the process or design of a finished product .
Most of the company thought that inspection is the only way to
achieve quality product which will fullfill customers' requirements. No doubt inspection is the fastest way to
deliver product which comply to the customers' requirements, however it is the most expensive way, as you
might need to reject more that 50% of
the product to screen out parts which do not comply to specification or customer requirement . The non compliance part need to be
reworked or worst scrapped which involve
cost. Hence inspection to get
‘quality” part should NOT be a long term
solution. Figure 3 below show the differences between
good design and well controlled process with poor design and badly controlled process which stress on the point
quality is design and build in.
From figure 3a above, you will notice an organization
with less than 50% compliance product (< 50% yield rate) have go to thru the
reworked or scrapped cycle 50 times more than an organization with yield rate
99% good parts in figure 3b.
Most companys' top management failed to recognize this fact
or some company who have some knowledge,
however failed to drive their design and engineering team to work
towards good quality product and manufacturing process design thus have to bear the cost of poor
quality.
Top 4 reasons why most company are unable to build quality
into product could be
Top management does have any knowledge
on quality engineering and only thought quality is achieved through inspection
Top management does not want to invest
in good quality engineering infrastructure which include qualified or certified quality engineer/manager
Top management does not realize that everybody including they
themselves are the one who contributed to
quality of the product and put the blame of poor quality on quality department
Top management has a “just do it”
attitude with no patience for proper planning,
not recognizing that they would
have to put in more time and money in inspecting quality and suffer from poor product and process design.
You will notice that I have faulted the top management, as Dr. Edward Deming (1900-1993), a famous
quality guru of past century had stated that management actually contribute
almost 85% of quality problem. Top
management is the major culprit of poor quality.
Therefore quality can only be achieved by having an
educated top management team in quality engineering and then proliferate it
down to the whole organization on the importance everyone in organization play
a role from quality product creation to finished goods.
Different
aspect of Quality management and quality engineering
There are many components within quality management and engineering function starting from the
most basic quality control to higher
level quality engineering and management.
I shall go thru each of them briefly for
the benefit of reader who had just being introduced to quality
engineering
Function
|
Focus
|
Description
|
Quality
control
|
Process
output (finished product)
|
the
most basic quality management function which focus on finished product inspection according to
customer requirement
|
Quality
assurance
|
Process
input (process steps)
|
Ensure
the all procedure or process steps need to make a product to ensure all
process step meets preset specification to produce good parts for customer
assurance
|
Quality
management system
|
Planning, design Process input , output and improve
|
Management
system is a set policies or guideline which company follows to ensure their
product or services consistently meet customer quality
requirement. The most universal quality
management system used is ISO
9001. There are four components in
quality management systems quality planning, quality control and quality
assurance and quality improvement
|
Quality
Planning
|
Establish
document plan
|
Developing plan which the organization has to adopt in
order to achieve a product which full fill customer requirement with fitness
for use
|
Quality
improvement
|
Program
|
A
program which use systematic methodology
well known models such as Advance product quality planning (APQP) six
sigma, 7 QC tools, PDCA model with the purpose of achieving quality
improvement objectively.
(you
can google those terms as there are many website which give detail explanation
& I shall cover in my future blog)
|
Quality
engineering
|
All aspect of plan, manage, execute, monitor
quality
|
Quality
engineering would encompasses (according to American Society of Quality :
·
Quality management and leadership – philosophies,
management system, leadership
principles, communication, customer relations and supplier management
·
Quality system – quality standards and audit, cost of
quality, quality training
·
Product and process design- product drawing, life cycle reliability
·
Product and process control - material control,
measurement system analysis
·
Continuous improvement using statistical tools six
sigma
|
I have reached the last
part of "introduction to quality" section of this blog. I hope
that my readers would have a better understanding on product quality
definition, ownership of quality, quality in every steps of product creation
and various function of quality. In the future I shall share details on
quality methodologies related to six sigma, case studies, statistical techniques in
quality engineering and of course my expertise in supplier quality management.
