1. Metrology Lab – Slide 1ME313 – Metals Processing - Lab Last Modified by PAN 2/19/05
Introduction to Metrology
ME 313 Manufacturing Processes
2. Metrology Lab – Slide 2ME313 – Metals Processing - Lab
Introduction
• Definition : The science that deals with
measurements and their units
• Basic Terminology:
• Reliability : The probability of achieving desired
results . ( To increase reliability,
accuracy and precision must
also be increased.)
• Resolution : The smallest graduation that a
measuring device possesses
3. Metrology Lab – Slide 3ME313 – Metals Processing - Lab
Accuracy vs. Precision
• Accuracy : Correctness (exactness) to the
actual value.
• Precision : Reproducibility / consistency of
measurements
In a dart game
one needs to utilize
both of these
in-order to win
Is this Accurate or Precise???
AccuratePrecise Accurate and Precise
4. Metrology Lab – Slide 4ME313 – Metals Processing - Lab
Micrometer
Divisions of 0.025”
Divisions of 0.100”
Divisions of 0.001”
Resolution is 0.001”
Reading Line
5. Metrology Lab – Slide 5ME313 – Metals Processing - Lab
How to Read a Micrometer
Vernier scale ***Resolution 0.0001” ***
Reading B
2 x 0.1000 = 0.2000
2 x 0.0250 = 0.0500
Final Reading = 0.2500
Reading C
2 x 0.1000 = 0.2000
2 x 0.0250 = 0.0500
7 x 0.0001 = 0.0007
= 0.2507Final Reading
6. Metrology Lab – Slide 6ME313 – Metals Processing - Lab
QUIZ TIME
A
B
Reading A
2 x 0.1000 = 0.2000
3 x 0.0250 = 0.0750
24 x 0.0010 = 0.0240
= 0.2991Final Reading
1 x 0.0001 = 0.0001
Reading B
3 x 0.1000 = 0.3000
0 x 0.0250 = 0.0000
= 0.3001Final Reading
1 x 0.0001 = 0.0001
0 x 0.0010 = 0.0000
What is the Resolution???
8. Metrology Lab – Slide 8ME313 – Metals Processing - Lab
Homework
Small Block
Short Plate
Long Plate
Small Cylinder
Large Cylinder
Edge Thickness
Edge Thickness
Diameter
Edge Thickness
Diameter
Vernier
Micrometer
Vernier
Caliper
0.0001” 0.001”Resolution :
*Should be included in the lab report*
Editor's Notes
1) Students are responsible for the terminology and their definitions
1) Data re**** must take in account the resolution of the measuring device.