Quality control is a process used to ensure a certain level of quality in products and services. It aims to ensure products and services meet specific requirements for being dependable, satisfactory, safe, and financially sound. Quality control occurs at various stages of production including when raw materials are received, during production, and when finished products are inspected before shipping to customers. It also involves evaluating service quality. Common quality control methods include product testing, inspections of manufacturing processes, and using tools like check sheets, control charts, histograms, flow charts, Pareto charts, and scatter diagrams.

1. QUALITY CONTROL
PRODUCTION AND OPERATIONS CONTROL
UNIT -5
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2. What is Quality Control?
Quality control is a process that is used to ensure a certain
level of quality in a product or service.
The basic goal of this process is to ensure that the products
or services that are provided meet specific requirements
and characteristics, such as being dependable, satisfactory,
safe and fiscally sound.
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3. Basic examples of Quality
Control:
Manufacturers of food products often have employees
who test the finished products for taste and other
qualities.
Clothing manufacturers have workers inspect garments
to ensure that they are properly sewn.
Service-oriented companies often have representatives
who observe the services being performed or who do
follow-up checks to ensure that everything was done
properly.
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4. When does Quality Control
occur?
1. When raw materials are received prior to entering
production.
2. Whilst products are going through the production process.
3. When products are finished - inspection or testing takes place
before products are despatched to customers.
4. Evaluating people. (Applicable with service-oriented
companies.)
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5. 7 Basic Tools of Quality.
1. Check sheet - is a form used to collect data in real time at the
location where the data are generated. The data it captures can be
quantitative or qualitative. When the information is quantitative, the
check sheet is sometimes called a tally sheet.
2. Control chart - also known as Shewhart charts or process-behavior
charts, in statistical process control are tools used to determine if a
manufacturing or business process is in a state of statistical control.
3. Histogram - is a graphical representation showing a visual impression
of the distribution of data.
4. Ishikawa Diagram - Common uses of the Ishikawa diagram
are product design and quality defect prevention, to identify
potential factors causing an overall effect. Each cause or reason for
imperfection is a source of variation. Causes are usually grouped into
major categories to identify these sources of variation.
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6. 5. Pareto Chart - is a type of chart that contains
both bars and a line graph, where individual values
are represented in descending order by bars, and
the cumulative total is represented by the line.
6. Scatter diagram - is a type of mathematical
diagram using Cartesian coordinates to display
values for two variables for a set of data.
7. Flow chart - is a type of diagram that represents
an algorithm or process, showing the steps as boxes
of various kinds, and their order by connecting them
with arrows
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