Page 270 - Aeronautical Engineer Data Book

216 Aeronautical Engineer’s Data Book
Table 12.1 Engineering abbreviations: USA
Abbreviation Meaning

ANSI American National Standards Institute
ASA American Standards Association
ASME American Society of Mechanical Engineers
AVG average
CBORE counterbore
CDRILL counterdrill
CL center line
CSK countersink
FIM full indicator movement
FIR full indicator reading
GD&T geometric dimensioning and tolerancing
ISO International Standards Organization
LMC least material condition
MAX maximum
MDD master dimension definition
MDS master dimension surface
MIN minimum
mm millimeter
MMC maximum material condition
PORM plus or minus
R radius
REF reference
REQD required
RFS regardless of feature size
SEP REQT separate requirement
SI Système International (the metric system)
SR spherical radius
SURF surface
THRU through
TIR total indicator reading
TOL tolerance

1 (1.5) (6)
1.6 2.5 4 6.3 10
R5: 5 10
0
0
R10: 10 10
1 251.6 2 2.5 3.15 4 5 6.3 8 10
(1.2) (1.5) (3) (6)

'Rounding' of the R5 and R10 series numbers
(shown in brackets) gives seies of preferred sizes
Fig. 12.2 The R5 and R10 series