Abbreviation	Description
AARH	Arithmetic Average Roughness Height
AG	Above Ground
AL	Aluminum
ATM	Atmosphere
AVG	Average
B&S	Bell & Spigot
BB	Bolted Bonnet
BBE	Bevel Both Ends
BC	Bolt Circle
BD	Blow Down
BE	Beveled End
BF	Blind Flange
BHN	Brinell Hardness Number
BL	Battery Limit
BLD	Blind
BLE	Bevel Large End
BOE	Bevel One End
BOM	Bill of Material
BOP	Bottom of Pipe
BR	Bronze
BSE	Bevel Small End
BTM	Bottom
BW	Butt Weld
BYP	Bypass
C	Centigrade; Celsius
C-C	Center to Center
CA	Corrosion Allowance
CALC	Calculated
CC	Chemical Cleanout
CI	Cast Iron
CL	Centerline
CLR	Centerline Radius
CM	Centimeter
CO	Cleanout
CONC	Concentric
CONN	Connection
CPLG	Coupling
CPM	Computational Pipeline Monitoring
CPVC	Chlorinated Polyvinyl Chloride
CR	Chromium
CS	Carbon Steel
CSC	Car Seal Closed
CSO	Car Seal Open
CTR	Center
CU	Copper
CVN	Charpy V-notch
CW	Continuous Welded
CWO	Chain Wheel Operator
CWP	Cold Working Pressure
DEG	Degree
DES	Design
DF	Design Factor
D/P	Differential Pressure
DI	Ductile Iron
DIA	Diameter
DIM	Dimension
DIN	Deutsches Institut für Normung
DN	Diameter Nominal (Metric)
DP	Design Pressure
DRN	Drain
DSAW	Double Submerged Arc Welding
DT	Design Temperature
DWG	Drawing
DWT	Drop Weight Tear
DWTDWG	Drop Weight Tear Drawing
EA	Each
EB	Extended Bonnet
EC	Eddy Current Testing (Examination)
ECC	Eccentric
ECDS	External Corrosion Direct Assessment
EFRD	Emergency Flow Restricting Device
EFW	Electric Fusion Welded
EL	Elevation
ELL	Elbow
ELLIP	Elliptical
EMI	Electro-Magnetic Inspection
EOL	Elbolet
EPDM	Ethylene-Propylene-Diene Terpolymer/EP Rubber
EQ	Equal
ERW	Electric Resistance Welded
ESD	Emergency Shutdown
EW	Electric Welded Process
F	Fahrenheit
F-F	Face-to-Face
FBE	Flange Both Ends
FCAW	Flux Cored Arc Welding
FEP	Perfluoro (Ethylene-Propylene) Copolymer
FF	Flat Face
FFW	Field Fit Weld
FIG	Figure
FIN	Finish
FLE	Flange Large End
FLEX	Flexible
FLG	Flange
FMU	Fitting Make Up
FNPT	Female National (Taper) Pipe Threads
FOB	Flat on Bottom
FOE	Flange One End
FOF	Face of Flange
FOT	Flat on Top
FP	Full Port
FRP	Fiberglass Reinforced Plastic
FS	Forged Steel
FSE	Flange Small End
FT	Foot; Feet
FTG	Fitting
FV	Full Vacuum
FW	Field Weld
G	Gram
GA	Gauge
GALV	Galvanized
GBE	Groove Both Ends
GE	Groove End
GJ	Ground Joint
GLE	Groove Large End
GMAW	Gas Metal Arc Welding
GO	Gear Operator
GOE	Groove One End
GR	Grade
GRND	Ground(ed)
GRP	Glass Reinforced Plastic
GSE	Groove Small End
GSKT	Gasket
GTAW	Gas Tungsten Arc Welding
H	Horizontal
HAZ	Heat Affected Zone
HB	Hardness Brinell Scale
HD	Head
HDPE	High Density Polyethylene
HB	Hardness Brinell Scale
HDR	Header
HEX	Hexagonal
HF	Hard Faced
HFW	High Frequency Welding
HK	Hardness Knoop Scale
HIC	Hydrogen Induced Cracking
HP	High Pressure
HPT	High Point
HR15N	Hardness Rockwell 15N Scale
HRB	Hardness Rockwell B Scale
HRC	Hardness Rockwell C Scale
HT	Heat Treatment
HV	Hardness Vickers Scale
HVL	Highly Volatile Liquid
HW	Handwheel
IBBM	Iron Body Bronze Mounted
ICDIA	Internal Corrosion Direct Assessment
ID	Inside Diameter
ILI	In-Line Inspection
IN	Inch
INS	Insulation
ISBL	Inside Battery Limits
ISO	Isometric Drawing
ISRS	Inside Screw Rising Stem
ITCS	Impact Tested Carbon Steel
JE	Joint Efficiency
KCS	Killed Carbon Steel
KG	Kilogram
KPA	Kilopascals (Pressure = psig x 6.895)
LB	Large Bore
LDPE	Low Density Polyethylene
LFW	Low Frequency Welding
LJ	Lap Joint
LP	Low Pressure
LPG	Liquefied Petroleum Gas
LPT	Low Po int
LR	Long Radius
LTE	Long Tangent Elbow
LW	Laser Welded Process
LWN	Long Welding Neck
M	Meter
MxF	Male by Female
MAOP	Maximum Allowable Operating Pressure
MAWP	Maximum Allowable Working Pressure
MAX	Maximum
MDMT	Minimum Design Metal Temperature
MFG	Manufacturer
MI	Malleable Iron
MIC	Microbiologically Induced Corrosion
MIN	Minimum
MISC	Miscellaneous
MJ	Mechanical Joint
MNPT	Male National (Taper) Pipe Threads
MO	Molybdenum
MOP	Maximum Operating Pressure
MPQ	Manufacturing Procedure Qualification
MPQT	Manufacturing Procedure Qualification Testing
MPS	Manufacturing Procedure Specification
MT	Magnetic Particle Testing (Exam)
MTL	Material
MTO	Material Take Off
MTR	Material Test Report
N	Normalized
N/A	Not Applicable
NBR	Nitrile-Butadiene/Nitrile or Buna N Rubber
NDE	Nondestructive Examination
NI	Nickel
NIPP	Nipple
NOZ	Nozzle
NPS	Nominal Pipe Size
NPT	National (Taper) Pipe Thread
NRS	Non-Rising Stern
NTS	Not to Scale
OD	Outside Diameter
ORIF	Orifice
OS&Y	Outside Screw & Yoke
OSBL	Outside Battery Limits
OVHD	Overhead
P&ID	Piping and Instrumentation Diagram
P-T	Pressure Temperature
PARA	Paragraph
PAW	Plasma Arc Welding
PBE	Plain Both Ends
PE	Polyethylene; Plain End
PFA	Perfluoro (Alkoxyalkane) Copolymer
PFD	Process Flow Diagram
PIG	Pipeline Inspection Gauge
PIV	Post Indicator Valve
PL	Plate
PPL	Pipeline
PLE	Plain Large End
PLR	Pig Launcher and Receiver
PLS	Pipeline Specification
PMI	Positive Material Identification
PMS	Piping Material Specification
PO	Pushed On
POE	Plain One End
POS	Point of Support
PP	Polypropylene
PPB	Parts per Billion
PPM	Parts per Million
PQR	Procedure Qualification Record
PRESS	Pressure
PS	Pipe Support
PSE	Plain Small End
PSI	Pounds per Square Inch
PSIA	Pounds per Square Inch Absolute
PSIG	Pounds per Square Inch Gauge
PSL	Product Specification Level
PT	Liquid Penetrant Testing (Exam)
PTFE	Polytetrafluoroethylene
PVC	Polyvinyl Chloride
PVDC	Polyvinylidene Chloride
PVDF	Polyvinylidene Fluoride
PWHT	Postweld Heat Treatment
QCP	Quality Control Procedure
RA	Roughness Average (Replaced AARH)
RAD	Radius
RAT	Rating
RCV	Remote Control Valve
RED	Reducer; Reducing
REF	Reference
REINF	Reinforced
REPAD	Reinforcing Pad
REQD	Required
REV	Revision
RF	Raised Face
RJ	Ring Joint
ROE	Radius of Exposure
RP	Reduced Port
RPO	Restrained Push On
RS	Rising Stem
RT	Radiographic Testing (Exam)
RTFE	Reinforced TFE
RTP	Reinforced Thermosetting Plastic
RTR	Reinforced Thermoset Resin
SAW	Submerged Arc Welding
SAWH	Submerged Arc Helical Welding
SAWL	Submerged Arc Longitudinal Welding
SB	Small Bore
SCADA	Supervisory Control and Data Acquisition System
SCC	Stress Corrosion Cracking
SCCDIA	Stress Corrosion Cracking Direct
SCH	Schedule
SD	Shutdown
SDR	Standard Dimensional Ratio
SG	Specific Gravity
SI	Silicon
SMAW	Shielded Metal Arc Welding
SMLS	Seamless
SMYS	Specified Minimum Yield Strength
SO	Slip On
SOL	Sockolet
SP-WD	Spiral Wound
SPA	Spacer
SPEC	Specification
SQ	Square
SR	Short Radius
SS	Stainless Steel
SSC	Sulfide Stress Cracking
ST	Seat
STD	Standard
STL	Steel
STM	Steam
SVC	Service
SW	Socket Weld (preferred)
SWG	Swage
T&C	Threaded and Coupled
T&G	Tongue and Groove
T-T	Tangent-to-Tangent
T/SW	Threaded by Socketweld
TAN	Tangent
TBE	Thread Both Ends
TDH	Total Differential Head
TEMP	Temperature
TFE	Tetrafluoroethylene
TFL	Through Flowline
THK	Thick
THRD	Thread; Threaded
TI	Titanium
TL	Tangent Line
TLE	Thread Large End
TOC	Top of Concrete
TOE	Thread One End
TOG	Top of Grout
TOL	Thredolet
TOP	Top of Pipe
TOS	Top of Steel; Top of Support
TP	Test Pressure
TSE	Thread Small End
TW	Thermowell
TYP	Typical
UB	Union Bonnet
UG	Underground
UNC	Unified National Coarse Thread
UNF	Unified National Fine Thread
UNS	Unified Numbering System
UT	Ultrasonic Testing (Exam)
V	Vertical
VAC	Vacuum
V/D	Vents and Drains
VT	Visual Testing (Exam)
W/	With
W/O	Without
WB	Welded Bonnet