Tek-Tips is the largest IT community on the Internet today!

Members share and learn making Tek-Tips Forums the best source of peer-reviewed technical information on the Internet!

  • Congratulations cowski on being selected by the Eng-Tips community for having the most helpful posts in the forums last week. Way to Go!

circularity / diameter tolerance

Status
Not open for further replies.

cervantes

Mechanical
Joined
Aug 3, 2006
Messages
85
Location
PL
hello one more time,

well, haven't found exact answer anywhere yet so I am asking:

1) if there is a hole, with diameter let's say 50 and tolerance M6 and no form and position tolerance (circularity) is given on the drawing (and default workshop circularity is let's say 0.1mm) so then I can not exceed tolerance diameter range anyway, isn't true? otherwise it does not have sense in my opinion

in other words: DO I NEED to specify circularity for drawing with diameter 50M6?...

2) If statement above is true and circularity is specified, but with higer range, then M6 tolerance has priority anyway?

thanks in advance
 
You are right, unless the required circularity is better than the restriction given by M6. Therefore, if circularity tolerance is given, it should always be less than the dimensional tolerance.
 
For circularity to be a valid specification it needs to be a refinement of the size specification.

----------------------------------------

The Help for this program was created in Windows Help format, which depends on a feature that isn't included in this version of Windows.
 
" DO I NEED to specify circularity for drawing with diameter 50M6 "

I'd say it could depend on the situation, notably the part function.

50 mm M6 = -4/-20 um.

If this is a high performance connecting rod journal (not the bore) the recommended roundness and taper should be 0.0002" or 0.0001" (5 um or 3 um) measured as a diameter.
 
Status
Not open for further replies.

Part and Inventory Search

Sponsor

Back
Top