Tag Archive | Statistical Process Control

Statistical Process Control (SPC)

Introduction :1. Statistical Process Control (SPC) is a technique pioneered by Dr Walter Shewhart in the 1920’s.  Dr Shewhart found that in any variation, there are two distinct sources
– Common or random cause
– Assignable or non random cause.
2.SPC control charts are useful in providing information to Process owner to advise them when and when not to adjust a process.
3.SPC was not fully utilised until after the 2nd  World War when Dr Deming introduced it to the Japanese Industry.
4.One of the key factors that have enabled Japanese companies to produced extremely high quality is the use of SPC.
5.It was not until the late 70’s that the American multinationals started to use SPC widely

Introduction:Some definition about SPC:
a)A statistical technique that is widely used to ensure that the process is meeting standards.
b)A technique using charts and graphs to check a production process to see if any way not functioning properly which could lead to poor quality.
c)An application of scientific method to control and improve manufacturing process.
d)A term used to describe the concept of using statistical tool to assist in controlling the quality of a process.

Benefits of SPC

  • Lower manufacturing costs
  • Correct standards
  • Stable processes
  • Realistic Specification
  • Less inspection
  • Decreased problem – to – solution lead time
  • Better customer relations
  • Reliable measures of capability
  • Improved forecasting
  • Improved product quality
  • Decreased cycle time

What is Statistical Process Control?

Statistical Process Control Explained
Statistical Process Control (SPC) is a set of tools designed to help reduce variation by identifying the source of variation, taking appropriate corrective action, and verifying the results.

  • Dr. Walter Shewhart of Bell Labs developed a theory of Statistical Process Control in 1924.
  • During the ’20’s Dr. Shewhart presented his theories in a series of lectures that were published in a book , Economic Control of Quality Manufactured Product (1931).
  • SPC came into wide use during the 1940’s as a result of war production efforts.