×
INTELLIGENT WORK FORUMS
FOR ENGINEERING PROFESSIONALS

Are you an
Engineering professional?
Join Eng-Tips Forums!
• Talk With Other Members
• Be Notified Of Responses
• Keyword Search
Favorite Forums
• Automated Signatures
• Best Of All, It's Free!

*Eng-Tips's functionality depends on members receiving e-mail. By joining you are opting in to receive e-mail.

#### Posting Guidelines

Promoting, selling, recruiting, coursework and thesis posting is forbidden.

# How to understand extrernalt micrometer CERTIFICATE of INSPECTION

## How to understand extrernalt micrometer CERTIFICATE of INSPECTION

(OP)
Hello,

Im trying to make some sense out of a Mitutoyo external micrometer CERTIFICATE of INSPECTION. Maybe someone smarter can comment my thougths.

So the way I understand it:

1) The process of inspection is set up in accordance to Mitutoyo Corp. internal standtard which is based on several international standards (violet lines).

2) According to Mitut. standard the permissible value of measuring faces flatness is 0,3 µm. The actual measured value is 0,0 µm for both the anvil and spindle (the actual value could have been <=0,04 µm, but they round it to one decimal place). And the permissible value for parallelism of measuring faces is 1 µm, the actual measured value is 0,3 µm. (red circle)

3) They have measured the lengths of some precision gauge blocks (25,00; 32,70...50,00 mm). For other gauge blocks the error was zero (actual error could have been <=0,04 µm, but they propably rounded it to one decimal point), but only for the 50,00 mm block the error was +1 µm, which is permissible.
(green box).

4) The uncertainty of measurement is U=1,4 µm. So this means, that if we don`t take operator, environment and workpiece uncertainty components into account, we can trust the measuring result to be correct with a possible deviation of +/-1,4µm . (yellow box)

BR

### RE: How to understand extrernalt micrometer CERTIFICATE of INSPECTION

You may want to post to "Measurement & control instrumentation engineering"

"For every expert there is an equal and opposite expert"
Arthur C. Clarke Profiles of the future

#### Red Flag This Post

Please let us know here why this post is inappropriate. Reasons such as off-topic, duplicates, flames, illegal, vulgar, or students posting their homework.

#### Red Flag Submitted

Thank you for helping keep Eng-Tips Forums free from inappropriate posts.
The Eng-Tips staff will check this out and take appropriate action.

Close Box

# Join Eng-Tips® Today!

Join your peers on the Internet's largest technical engineering professional community.
It's easy to join and it's free.

Here's Why Members Love Eng-Tips Forums:

• Talk To Other Members
• Notification Of Responses To Questions
• Favorite Forums One Click Access
• Keyword Search Of All Posts, And More...

Register now while it's still free!