• SIX SIGMA BELTS
What is six sigma?
•Sigma is a measure of “goodness: the capability
of a process to produce perfect work.
• A “defect” is any mistake that results in customer
• Sigma indicates how often defects are likely to occur.
• The higher the sigma level, the lower the defect rate.
• The lower the defect rate, the higher the quality.
The Six Sigma Evolutionary Timeline
1818: Gauss uses the normal curve 1924: Walter A. Shewhart introduces
to explore the mathematics of error the control chart and the distinction of
analysis for measurement, probability special vs. common cause variation as
analysis, and hypothesis testing. contributors to process problems.
1736: French 1896: Italian sociologist Vilfredo
mathematician Alfredo Pareto introduces the 80/20
Abraham de rule and the Pareto distribution in
Moivre publishes Cours d’Economie Politique.
1949: U. S. DOD issues Military
Procedure MIL-P-1629, Procedures
1960: Kaoru Ishikawa
for Performing a Failure Mode Effects
introduces his now famous
and Criticality Analysis.
1941: Alex Osborn, head of 1970s: Dr. Noriaki Kano
BBDO Advertising, fathers a introduces his two-dimensional
widely-adopted set of rules for quality model and the three
“brainstorming”. types of quality.
1986: Bill Smith, a senior
engineer and scientist introduces 1995: Jack Welch
the concept of Six Sigma at launches Six Sigma at GE.
1994: Larry Bossidy launches
Six Sigma at Allied Signal.
Why six sigma?
• Sigma allows comparison of products and services
of varying complexity
• Also, it provides a common basis for benchmarking
(competitors and non-competitors).
• The higher the sigma level, the better your operation
• Sigma measures how well you’re doing in getting
to zero defects.
Cost of poor quality.
Traditional Costs Real but Overlooked
Long Cycle Time
Cost of Capital
Idle Time Lost Sales
Rework Lost Customer Loyalty
Is it a Goal, a Measure, a Process, or a Tool?
Our Performance Compared to Competitors
• Quality • OTD
Importance to Customers
• Complaints to-’Low’
We’re Better They’re Better
Operational Excellence Training
(Distribution Shifted ± 1.5)
Process Defects per Million
•Human Resources: reduce the number of requisitions
unfilled after 30 days.
•Customer Service: measure the number of calls answered
on the first ring.
•Order Fulfillment: eliminate Customer returns because of
incorrect parts or product being shipped.
•Finance: reduce the instances of accounts being paid
after a specified time limit has elapsed.
How Six sigma is calculated???.....
• SIX SIGMA BELTS
it is an approach undertaken to improve existing business
Six sigma acronym of 5 interconnected phases of a process
improvement project.following are the phases:
1.Define high-level project goals and the current process.
2.Measure key aspects of the current process and collect relevant data.
3.Analyze the data to verify cause-and-effect relationships. Determine
what the relationships are, and attempt to ensure that all factors have been
4.Improve or optimize the process based upon data analysis using various
5.Control to ensure that any deviations from target are corrected before
they result in defects.
Tools used for dmaic
1. Stakeholders analysis
2. VOC 1.FMEA
3. Surveys Improve 2.Pareto analysis
4. CTQ’s 3.Data collection
5. Benchmarking 4.PDSA cycle
5. Run charts
(PDSA) Cycle Control
Cause and Effect Chart Team
Plan, Do, Study,
Act (PDSA) Cycle
This approach is undertaken when there is a
need to create new design or product:
5 steps in DMADV approach-
Define design goals that are consistent with customer demands and the
Measure and identify CTQs (characteristics that are Critical To
Quality), product capabilities, production process capability, and risks.
Analyze to develop and design alternatives, create a high-level design
and evaluate design capability to select the best design.
Design details, optimize the design, and plan for design verification.
This phase may require simulations.
Verify the design, set up pilot runs, implement the production process
and hand it over to the process owners.
DMADV is also known as DFSS, an abbreviation of "Design For Six
1.Defines a 2.Measure
business process customer needs
current process 3.Analyze options
to meet customer
cause of the V/S satisfaction
designed to meet
4.Improvements customer needs
made to reduce
defects 5.Model put
5. Keep check on simulation tests
future for verification
• SIX SIGMA BELTS
The six sigma organization.
The six sigma team has five levels of
What is a BELT?
Belt refers to the level or the position, of a person in an
organization at the time of performing a work or at the
time of implementation of a project.
There are four “Belt” levels :-
2. Master black belt(MBB)
3. Black belt(BB)
4. Green belt(GB)
5. Yellow belt(YB)
•Lay down policies and guidelines regarding
functioning of six sigma teams
•Approves six sigma projects
•Removes road blocks in the path of six sigma
•Make available necessary resources
•Sort out conflicts
Master black belts
The highest level of Six Sigma expertise;
All duties involve implementation of Six
Sigma, including statistical
analysis, strategic and policy planning and
implementation, and training and mentoring
of Black Belts.
a Six Sigma-trained professional who has usually
completed an examination and been certified in its
all job duties include implementation of Six
Sigma methodology throughout all levels of the
leading teams and projects, and providing Six
Sigma training and mentoring to Green and Yellow
In many organizations, Six Sigma's "entry
a Six Sigma-trained professional who does
not work on Six Sigma projects exclusively,
but whose duties include leading projects
and teams and implementing Six Sigma
methodology at the project level
The lowest level of Six Sigma expertise;
applies to a professional who has a basic working
knowledge and who may manage smaller process
but who does not function as a project or team
Number game In hierarchy
15 - 20
• SIX SIGMA BELTS
Principles underlying six sigma
•Variability is necessary.
•Total variability is the result of two types of
causes : chance causes and assignable causes .
chance causes cant be identified and hence can
not b e eliminated while assignable causes can
be identified and immediately eliminated.
•Process means in real life can shift from the
nominal mean by 1.5 times of standard
•Defects are randomly distributed throughout
the units, and parts and processes are
6.For execution of any operation certain standard is
specified for the output and some variations are allowed
from the ideal measure.
These requirements are usually stated in terms of
USL=upper specification limit
LSL=lower specification limit
Defects are randomly distributed throughout the units
and parts and processes are individual. since measured
values follow a normal distribution with mean and
standard deviation, the process capability of the process
will be equal to mean.
•Since process mean in real life can shift from
nominal by 1.5 times the standard deviation
due to gradual drift or as a result of sudden
drift, defects rates in practice expected at a
different sigma levels are higher than in the
mean centered process.
•Measurements are the key elements
How six sigma can reduce defects?
•By reducing the value of
variation (standard deviation).
•Increasing the design width.
Defects in six sigma.
•Six sigma is extracting but not
•Detraction from creativity
•Six sigma not for small business