Engineering Drawing Abbreviations and Symbols – Technical & Mechanical Design Symbols | CNCLATHING


You may easily identify the abbreviation KG and CM, do you know the meaning of CYL and EQUI SP on a CNC design? These abbreviations used in engineering drawings along with symbols to specify the details and characteristics of the drawing instead of the full word, which terms are commonly used? Here we collected the standard engineering drawing abbreviations and symbols to provide help for users.

Why Use Abbreviations and Symbols in Engineering Drawings

A good design drawing can indicate all the details needed to produce a mechanical CNC milling part in an easy way. Because there is no large space on a drawing to contain all the text to illustrate the image, abbreviations, and symbols are often used in engineering drawings to communicate the characteristics of the product to be manufactured. Engineering drawing abbreviations and symbols are concise and easy to understand for people from any country, also save space and make the drawing looks more pleasing to the eye.

Technical standards are made to define and provide glossaries of abbreviations, acronyms, and symbols that may be found on engineering drawings. There are different types of International Engineering Standards applied, including International (ISO), Australia (AS), France (AFNOR), Germany (DIN, WR), Italy (UNI), Japan (JIS), Korea (KS), Sweden (SS), UK (BS), USA (AISI, ANSI, ASTM, SAE, AMS). Please note that the same abbreviation may have different meanings in different categories. 

Common Engineering Drawing Abbreviations

The technical engineering drawing abbreviations we outline here are the terms used in the manufacturing and inspection of parts and assemblies. You can find the list of common engineering drawing abbreviations. 

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

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. You can also check out the GD&T symbols and terms on our site.