2. Contents
Introduction to Quality management
Statistical Quality control (SQC)
Terms in SQC
Control charts
Sampling procedure
Quality Circles
ISO and TQM
3. Introduction to QM
Quality management can be
defined as the process that
includes all activities of the
performing organization that
determines the quality policies,
objectives and responsibilities so
that the project will satisfy the
need for which it has been
undertaken.
4. Statistical Quality Control (SQC)
SQC is the application of
statistical techniques to accept
of rejects products already
produced (Acceptance
sampling) or to control the
process and therefore ensuring
product quality ( Process
control)
5. Terms in SQC
Variables – Indicate the permissible limits of
deviation away from standard parameters
Attributes – Indicate whether the lot is good
or bad.
Chance Cause – are those reasons in the
process that contribute to minor variations in
quality
Assignable Cause – are large variations from
the set quality parameters, that is not
acceptable.
6. Terms in SQC
Type 1 error – Error in sampling inspection,
where the process is normal yet samples
are inferred defective.
This is called as Producers Risk - Alpha
Type 2 error – this happens when the
process is erroneous, however the sample
turns out to be misread as good.
This is called as Consumers Risk - Beta
7. Control Charts
Control charts are of two types
a) variable charts and
b) attributes charts.
Variable charts – Control chart for variables are
used to control the quality of a product,
quantitatively measureable and expressed in
specific units of measurements such as
diameter, length, tensile strength etc.
Attributes charts – the quality of the product is
measured qualitatively on the basis of
classification such as presence or absence of a
character.
8. Sampling Procedure
Single Sampling – A sampling plan for single
sample is specified by two numbers n and c,
where n = sample size and c= maximum number
of defectives
Double sampling – One sample is drawn initially.
Two acceptance numbers c1 and c2 (c2>c1) are
selected. If the number of defectives in the first
sample lot is less than c1, then the lot is accepted.
Sequential sampling – it is a continuous sampling
decision where the samples are selected
randomly from various batches to determine
consistency.
9. Quality Circles
Quality circles is a part of the kaizen quality
management program.
It consist of 5 to 15 volunteers from the group
of workers to sit weekly or biweekly for an
hour to identify, analyze and search for
solutions to work related problems and ways
of implementing a solution.
10. ISO and TQM
ISO – stands for International standards for Organization.
Founded on the 23rd February,1947. Has 150 member
countries and head quartered at Geneva, Switzerland.
ISOS is a Greek word that mean equal or homogenous.
Objective of ISO is to promote development of
standardization and related activities in the world
ISO 1 to ISO 39,999 documents are available covering
various aspects from steel to software.
ISO 900 is related to the production, where ISO 14000 is
related to environment management in production set
up.
ISO certificates are valid for three years, with concurrent
audits done once every year.
11. ISO and TQM
TQM stands for Total quality
management. TQM was initiated by
Deming and Juran soon after the
world war 2.
TQM deals with addressing systems
that leads to defective products.
TQM is based on holistic well being of
all system; in order the delivered good
is confirmed to meet the quality
standards
12. Assess yourself
Have you understood the idea of SQC
What is the purpose of control charts
Differentiate type 1 versus type 2 error
Are quality circles still useful in businesses
Do you know the concept of Kaizen quality
management program