A drawing is a visual representation of an object which can be interpreted by someone else. Engineering drawings are a type of technical drawing, which is used to document the design and manufacturing process. Engineering drawings are also known as technical drawings or mechanical drawings.
In order to create an engineering drawing, symbols and abbreviations are used. These symbols and abbreviations are called engineering drawing abbreviations or engineering symbols. The most common types of engineering symbols include: arrows, circles, lines, shapes, numbers, letters and words.
Why Use Abbreviations and Symbols in Engineering Drawings
Engineers use abbreviations and symbols to quickly communicate their ideas to other engineers. These symbols are often used in engineering drawings to shorten the time it takes to draw them.
Engineers use abbreviations and symbols because they are more efficient than writing out the whole word or sentence. Symbols are often used in engineering drawings because they take less time for an engineer to draw than writing out the whole word or sentence.
Common Engineering Drawing Abbreviations
Engineers use a lot of abbreviations in their drawings. This makes it difficult for the non-engineer to read them. In order to make the drawings more readable, engineers need to be aware of the following abbreviations and their meanings:
AF: Across Flats
ASSY: Assembly
CM: Centimeters
CL: Center line
CHAM: Chamfered
CH HD: Cheese Head
CSK: Countersink
CSK HD: Countersink Head
C’BORE or CBORE: Counterbore
CYL: Cylinder or Cylindrical
DATUM: Datum System
“: Degree (of angle)
DIA: Diameter
DIM: Dimension
DRG: Drawing
ENG: Engine, engineering
EQUI SP: Equally Spaced
EXT: External
FIG: Figure
FT: Foot
GAL: Gallon
GALV: Galvanized
HRA: Hardness Rockwell A scale
HRB: Hardness Rockwell B scale
HRC: Hardness Rockwell C scale
HRD: Hardness Rockwell D scale
HRE: Hardness Rockwell E scale
HB: Hardness Brinell
HV: Hardness Vickers
HEX: Hexagon
HEX HD: Hexagon head
HYD: Hydraulic
IN: Inch
INSUL: Insulated, insulation
INT: Internal
I/D: Internal diameter
JT: Joint
KG: Kilogram
LH: Left hand
LG: Long
M/C: Machine
MATL: Material
MAX: Maximum
M: Meter
MM: Millimeter
MIN: Minimum, Minute
NTS: Not to scale
NO.: Number
O/D: Outside diameter
PCD: Pitch circle diameter
QTY: Quantity
LB: Pound
RAD or R: Radius
RPM: Revolutions per minute
RH: Right hand
RD HD: Round head
SCR: Screwed
SK: Sketch
SPEC: Specification
SPH: Spherical
SQ: Square
STD: Standard
SWG: Standard wire gauge
THD: Thread
TPI: Thread per inch
VOL: Volume
WT: Weight
More engineering drawing abbreviations can be used in CNC manufacturing:
AC: Across corners
ALY: Aluminum
ANN: Anneal
AQL: Acceptable quality level
AR: As required
AVG: Average
BASIC or BSC: Basic dimension
BC or B.C.: Bolt circle
BHC: Bolt hole circle
BRZ: Bronze
CAD: Computer-aided design
CERT: Certification
CI: Cast iron
CNC: Computer Numerical Control
CRES: Corrosion-resistant
DIM: Dimension
ED: Edge distance
IAW: In accordance with
LMC: Least material condition
MBP: Measurement between pins
MBW: Measurement between wires
MFD: Manufactured
MFG: Manufacturing
MFR: Manufacturer
MMC: Maximum material condition
OAL: Overall length
PC: Piece
PD: Pitch diameter
PL: Parts list
PMI: Product and manufacturing information
REF: Reference
RZ: Roughness, mean depth
SFACE: Spotface
SN: Serial number
STD: Standard
UNC: Unified National Coarse
UNS: Unified National Special
YS: Yield Strength
Engineering Drawing Symbols
The common Engineering Drawing Symbols are used for various purposes. They are used to convey information about the drawing, such as the type of drawing, the size and scale of the drawing, and other relevant information. The following is a list of symbols that are commonly found in engineering drawings:
Basic types of symbols used in engineering drawings are countersink, counterbore, spotface, depth, radius, and diameter. Here are more commonly used engineering drawing symbols and design elements as below.
