Statistical Process Control (SPC) Tools - 7 Basic Tools

Statistical Process Control (SPC) Tools - 7 Basic Tools

1. 2013.10.22
By ML
SPC - 7 BASIC TOOLS

2. STATISTICAL PROCESS
CONTROL (SPC)-7 BASIC TOOLS
1.Check Sheet
2.Stratification
3.Scatter Diagram
4.Histogram
5.Pareto Chart
6.Control Chart
7.Cause and Effect
Diagram

3. CHECK SHEET
Data record
Develop a matrix
for data collection.
Checklist
To list all necessary
items and their
status.

4. STRATIFICATION ANALYSIS
Stratification
Variables
Stratification
Tables
Graph chart
Advanced
chart
To group your
data by a
stratification
variable.
Summary
Statistics by
Groups or Levels
of an Output. „
Common
Summary
Statistics include:
„ Mean, Standard
Deviation, Sums,
Counts
Bar Graphs /
Pie Charts /
Flow Chart /
Contingency
table.
Stratify
distributions
using multiple
histograms or
multiple box
plots

5. …X and Y
EXPLAIN THE RELATIONSHIP
BETWEEN..
SCATTER DIAGRAM

6. HISTOGRAM
Normal manufacturing
process, normal quality
Data from
difference sources.
Limitation

7. HISTOGRAM VS. BAR GRAPH
Histogram





Bar chart (bar graph)

Normal manufacturing
process, normal quality
Size, shape and
the density of
interval.
Height

The distribution of
research subject.

8. CREATING HISTOGRAM
1.Collecting input data (n>50).
2.Define K (base on sampling size, density of the bin, narrow the
interval)
Either the experience or use the formula K=1+3.32*log(n)
3.Define I
the Range : R=Xmax – Xmin
i= R/ K (take the odd number)
4. Bin range
L = Xmin-(unit/2), U=L+I …apply to other number, till > Xmax
5. On the Tools menu, click Data Analysis.
6. In the Analysis Tools box, click Histogram, and then click OK.

9. Check Sheet A systematic and constantly, data record
collection.
Stratification Category the cause of variation, distinct the
difference.
Scatter
Diagram
To find out the relationship of two variables.
Histogram Represent tabulated frequency, often for
density estimation.
Problem identification
Cause and effect
relationship
Problem
identification
Cause and effect
relationship
Cause and effect
relationship
Problem
identification
we found the process in red circle is
the major problem.
we noticed that its not a normal
distribution thru histogram chart.
Clarify with the issue ‘X’, does it
associate with factor ‘Y’;
the other way is to stratify the process
which in red circle.
REVIEW THE 4 BASIC TOOLS

10. CAUSE AND EFFECT DIAGRAM
Measurement Materials Method
Analytical procedure
Sampling

11. REVIEW THE OTHER 3 BASIC TOOLS
Pareto Chart 80-20 rule.
Control Chart With comparing lines, to find and correct
the process variation when unpredictable
(out of control).
Cause and Effect
Diagram
The fishbone diagram identifies many
possible causes for an effect or problem. It
can be used to structure a brainstorming
session. It immediately sorts ideas into useful
categories.

12. ADDRESS YOUR CONCLUSION
Follow MECE Principle
mutually exclusive and collectively exhaustive


East West South North
direction

East West North

East
South
West
North
Blue
Seattle
East ←
South ↓
West→
North ↑
Blue
Seattle
Summarizing
East west south north
Find what’ve been missing
Grouping
← → ↑