quality control and assurance

Statistical
Process Control 6.2



© 2014
© 2018
Pearson
Pearson
Education,
Education,
Inc.Inc. S6 - 1

, Learning Objectives
When you complete this supplement you
should be able to :
1. Explain the purpose of a control chart
2. Explain the role of the central limit theorem in
SPC
3. Build -charts and R-charts
4. List the five steps involved in building control
charts
x
5. Build p-charts and c-charts
6. Explain process capability and compute Cp and
Cpk
7. Explain acceptance sampling
© 2014 Pearson Education, Inc. S6 - 2

, Statistical Process Control

The objective of a process control
system is to provide a statistical
signal when assignable causes of
variation are present




© 2014 Pearson Education, Inc. S6 - 3

, Statistical Process Control
(SPC)
► Variability is inherent
in every process
► Natural or common
causes
► Special or assignable
causes
► Provides a statistical signal when assignable
causes are present
► Detect and eliminate assignable causes of
variation
© 2014 Pearson Education, Inc. S6 - 4