This document provides information on various quality control techniques used in manufacturing including Just-in-Time (JIT), quality at source, inspection, quality circles, statistical quality control (SQC), quality control (QC), total quality management (TQM), and ISO 9000 standards. It describes how these techniques help ensure economic production and customer satisfaction through preventing defects, standardizing processes, enforcing problem-solving, and continually improving quality. The document also outlines the objectives, benefits, and key concepts of ISO 9000 certification for quality management systems.

1. CALCUTTA INSTITUTE OF
TECHNOLOGY
DEPARTMENT:-MECHANICAL ENGINEERING
SUBJECT NAME:- DESIGN OF MACHINE ELEMENTS
TOPIC: - QUALITY CONTROL
YEAR:-3RD SEMESTER:-6TH
ROLL NO:-17700721032

2. Quality control

3. Quality
• Quality refers to the sum of the attributes or
properties that describe a product
• These are generally expressed in terms of
specific product characteristics such as length,
width, colour, specific gravity and the like.
– Performance
• Conformity to performance standards

4. Definition
• ASQC – Quality means the totality of features
and characteristics of a product or service
that bear on its ability to satisfy given needs
• From customer’s perspective, quality of a
good or service is fitness for use of it
• Customer satisfaction for the price of the
product

5. • Quality is a blend of:
–Fitness of purpose, adequacy of functioning
and reliability, for the price paid
–Design and manufacturing characteristics
tailored to meet customer’s requirements
during service
–Availability when required

6. Quality control
• Quality control is a management system for
initiating and co ordinating:
– Quality development, quality maintenance and
quality improvement in the various departments
of design and manufacturing, for achieving the
twin objectives of:
Economical production and customer satisfaction

7. Objectives of Q C
• It is to provide products which are
dependable, satisfactory and economical
• To ensure economic production of
products of uniform quality acceptable to
the customer
• Aims at preventing the defects rather
than detecting the defects

8. Need for quality
• Increased productivity
• Reduced cost of repairs
• Increases loyal customer base
• Better profits

9. Quality creation
• Those activities involved in the selection of
the specific characteristics required to achieve
the desired quality and the processing or
fabrication of materials to conform to the
specific characteristics selected.
• Quality creation involves almost all
organisational elements of the enterprise and
is the basic objective towards which most
activity is directed

11. Quality control through Production systems
• Inputs – Raw materials – acceptance tests-
quality of inputs
• Conversion – production processes-control
charts- monitoring quality of partially
completed products
• Outputs- goods & services – acceptance tests-
quality of outputs

19. Quality control Techniques
• JIT
• Quality at source
• Inspection
• SQC
• QC
• TQM

20. JIT
• JIT helps achieve quality because it is a
philosophy that seeks to constantly improve
production processes and methods.
• JIT contributes to high product quality in the
following ways
– Production is highly standardised. Workers
perform standard tasks every day. They are
familiar with their tasks. Familiarity ensures high
quality

21. – In process inventories are drastically reduced by
cutting lot sizes. Any interruption, therefore
causes production to stop until the problem has
been solved. In this way, JIT has been called a
system of enforced problem solving. Now, this
stoppage in production forces everybody to solve
the quality problem so that the defect will not
repeat. Hence high product quality is ensured.
– Suppliers of materials, under JIT system, supply
materials of perfect quality. Many companies do
not even inspect suppliers’ deliveries of materials;
rather, the emphasis is on working with suppliers
to produce perfect parts and materials.

22. – JIT system envisages the use of automated
equipment and robots in production processes.
Use of such sophisticated machines will ensure
high product quality.
– JIT system also envisages the use of intensive
preventive maintenance programmes in order to
prevent any machine breakdown. This results in
machines producing parts of perfect quality.
– Workers are responsible for producing parts of
perfect quality or with zero defects before they are
passed on to the next production operation.

23. Quality at the source
• The worker is put in the driver’s seat in
controlling product quality. The principles
underlying quality at the source are:
– Every worker’s job becomes a quality control station.
The worker is responsible for inspecting his own
work, identifying any defects and reworking them in
to non-defectives, and correcting any causes of
defect.
– Statistical quality control techniques are used to
monitor the quality of parts produced at each work
station/ and easy-to-understand charts and graphs
are used to communicate progress to workers and
managers .

24. – Each worker is given the right to stop the
production line to avoid producing defective parts
– Workers and managers are organised into quality
circles- groupes of people who analyse quality
problems, work to solve the problems, and
implement programmes to improve product
quality.

25. Inspection
• The act of determining conformance or non-
conformance of the expected performance is
the function of inspection. By inspection, a
manager seeks to determine the acceptability
or non- acceptability of the parts, products or
services. The basis for inspection is usually a
specification which is called inspection
standard. Inspection is made by comparing
the quality of the product to the standard.

26. Frequency of inspection
• The challenge is to keep inspection costs
minimum, yet realise expected quality. In
certain cases every part is inspected, in which
case, it is called 100 percent inspection. When
it is less than 100 percent , it is called partial
or sampling inspection. Parts with high value
and those having tendency to run in to large
number of rejects are normally subject to
100% inspection.

27. When to inspect
• Inspection is desired at
– Finished products and parts to know that correct
parts are to be assembled or products are right
when shipped,
– Before an expensive processing,
– The out put of automatic machine periodically so
that possible errors are confined to small
quantities, and
– Before an operation that can’t be undone, for
example, in mixing paint.

28. Where to inspect
• Crib inspection
• On line inspection

29. Quality Circle
• It is a participative management concept
• Though it is in Japan that this was concretised
and demonstrated its potential, its
rudimentary origin is traced to USA, where
problem solving groups have existed since the
1930s.
• QC – Japan -1960s – Edward Deming & Joseph
Juran
• Dr. Ishikawa – Advisor with JUSE - 1962

30. Meaning & Nature
• QC is a voluntary group of people who meet
togethet on a regular basis to identify, analyse
and solve quality, productivity, cost reduction,
safety and other problems in their work area,
leading to improvement in their performance
and enrichment of their worklife.
• Ideal size of QC is around 10 memebers
• Employee problem solving groups

32. Objective or philosophy of QC
• Reduce errors and enhance quality and
productivity
• Inspire more effective teamwork
• Promote job involvement and participation
• Increase employee motivation
• Create problem solving capability
• Build an attitude of ‘problem prevention’
• Improve communication in the organisation

33. • Develop harmonious manager – worker
relationship
• Promote personla and leadership
development
• Develop a greater safety awareness
• Promote cost reduction
• Catalyse attitudinal changes for greater
cohesiveness and teamwork

34. Process of QC
• Identification of problem
• Problem selection
• Problem analysis
• Recommendation to the Top management

35. Deming’s 14 points
• Consistency of purpose is a must for continual
improvement of a product. Manager‘s have to
ensure that the company’s vision of quality is
understood by all the employees and that they
move continuously towards it.
• Continuous change and innovation is a must for
survival. In today’s complex business situations,
it is impossible for a small group of mangers to
identify and sort out quality problems. Thus all
the employees have to be involved in this
process.

36. • Quality cannot be achieved only by
inspection. Inspection wastes valuable time
and adds to the products cost without any
value addition. Inspections may not be
perfect, causing some defects to be passed on
to the customer. Defects are symptoms
removed by inspection, while the disease
(root cause) remains. Inspections create a gap
between the people and processes that
introduce defects and the people and
processes that detect defects

37. • Wastes should be eliminated in every
functional area, not just production. Even
processes in accounting, HRM, customer
service, and sales effect the quality of the
product and, thus, generate waste. Therefore,
the whole organisation should contribute
towards the enhancement of quality.

38. • The attitude of supervisors and managers
towards workers should be that of a facilitator.
Errors by workers should be treated by
supervisors as an opportunity to learn the
process and systems better. Teamwork should
be promoted and rewarded.

39. • The barriers between departments and
individuals should be removed. Problems
should not be handled within strict functional
limits and the concerns raised by related
functional areas should not be ignored.

40. • Posters and slogans should be eliminated.
These must not be used to tell the workers to
work harder. Instead, they should be provided
with tools and training so that they work
smarter leading to better quality.

41. • Remove obstacles in the good workmanship of
hourly workers to instill a sense of pride in
them.

42. • Vigorous programme of retraining and
education of employees are a must.
• Numerical targets and work standards may
affect quality. Reasonable numerical targets
make the workers complacent, while
excessively demanding ones may lead to a
compromise on quality in order to achieve the
targets. Such targets cannot be eliminated,
but can be set such that quality is not
compromised.

43. • Encourage workers to give quality
improvement ideas without fear. Workers
refrain from giving new ideas of change
because they may have to work with new and
unfamiliar methods in place of known and
comfortable, though inefficient, methods.
They also feel that if their ideas fail, it may
affect their performance appraisal, eventually
leading to job insecurity.

44. • Employees should be trained on the job.
Training on quality techniques should be
continual, as training never ends.

45. • The lowest price should not be the sole
criteria for selecting a supplier. Suppliers
asking for lowest prices often offer low quality
products, leading to an increase in the overall
cost to the buyer due to the increased
expenses of inspection, scrap, rework, and
inventory to replace defective items, etc. Thus,
the supplier offering the lowest total cost
should be selected.

46. • The top management’s commitment for ever
improving quality is a must.

47. ISO
• International Organisation for Standardisation
– Geneva
– 140 members
– 1979 – Genesis of ISO 9000

48. ISO 9000
• ISO 9000 standard represents an international
consensus on good management practices
with the aim of ensuring that the organisation
can time and again deliver the product or
services that meet the client’s quality
requirements. These good practices have been
distilled into a set of system, regardless of
what the organisation does, its size, or
whether it is private or public sector.

49. ISO
• Objective:
– To promote the development of standardiastion
and related activities in the world with a view to
facilitating international exchange of goods and
services, and to developing cooperation in the
spheres of intellectual, scientific, technological
and economic activity.

50. Principal concepts
• Demonstrate ability to consistently provide
product to meet customer and applicable
regulatory requirements
• Enhance customer satisfaction
• Improve the quality of its own operations
• Provide confidence to internal management
and interested parties that the requirements
of a quality management system are being
effectively implemented.

51. Benefits
• ISO 9000 certification has become the de facto
minimum requirement for entering into global
markets
• It provides an opportunity to increase value to
the activities of the organisation, by
streamlining quality management system.
• Improves the performance of processes/
activities continually thereby reducing the cost
of production

52. • It gives importance to customer satisfaction
• It helps to improve customer relations by
providing quality product or service
• It also acts as an incentive to develop
employee relations, employee empowerment
and organisational development