[object Object]Engineering Information, Conversions and Calculations

Thread Designations

Charts giving ISO and ANSI Thread Designations and Common Thread Names and Abbreviations.

ISO or ANSI

Designation

DESCRIPTIONRef. ANSI, BS, ISO
ACME CAcme Threads, CentralizingB1.5
ACME GAcme Threads, General PurposeB1.5
AMOAmerican Standard Microscope Objective ThreadsB1.11
ANPTDryseal Special Taper Pipe ThreadsB1.20.3
AWWAUnderground Service Line Valves and FittingsC800-84
BABritish Screw ThreadsBS.57
BSFBritish Parallel Screw ThreadsBS.84
BSWBritish Parallel Screw ThreadsBS.84
BUTTButtress Threads, Pull TypeB1.9
DINGerman Specifications-
F-PTFDryseal Fine Taper Threads SeriesB1.20.3
GStraight Pipe ThreadsBS.2779
ISOInternational Standard Organization-
JISJapanese Industrial Standard-
MMetric Screw Threads-M Profile with Basic ISO 68 ProfileB1.13M B1.18M
MJMetric Screw Threads-MJ Profile with Rounded Root of Radius 0.15011P to 0.18042PB1.21M
MJSMetric Screw Threads-MJ Profile Special SeriesB1.21M
NC5Class 5 Interference Fit External ThreadsB1.12
NC5Class 5 Interference Fit Internal ThreadsB1.12
NC5 IFEntire Ferrous Material RangeB1.12
NC5CSFFor Driving Copper Alloy and Soft Ferrous Material of 160 Bhn or LessB1.12
NC5HFFor Driving in Hard Ferrous Material of Hardness over 160 BhnB1.12
NC5ONFFor Driving in Other NonFerrous Material (Nonferrous Materials Other Than

Copper Alloys, Any Hardness

B1.12
NCF INFEntire Nonferrous Material RangeB1.12
NFPA 1963Fire Hose Threads-
NGONational Gas Outlet ThreadsCGA V-1
NGSNational Gas Straight ThreadsCGA V-1
NGTNational Gas Taper Threads (See Also SGT)CGA V-1
NHAmerican Standard Hose Coupling Threads of Full FormB1.20.7
NHRAmerican Standard Hose Coupling Threads for Garden Hose ApplicationsB1.20.7
NPSCAmerican Standard Straight Pipe Threads in Pipe CouplingsB1.20.1
NPSFDryseal American Standard Fuel Internal Straight Pipe ThreadsB1.20.3
NPSHDryseal American Standard for Hose Coupling Joints with Straight Internal

External Loose Fitting Thread

B1.20.7
NPSIDryseal American Standard Intermediate Internal Straight Pipe ThreadsB1.20.3
NPSLAeronautical National Form Taper Pipe ThreadsMIL P-7105B
NPSMAmerican Standard Straight Pipe Threads for Free-Fitting Mechanical

Joints for Fixtures

B1.20.1
NPTAmerican Standard Taper Pipe Threads for General UseB1.20.3
NPTFDryseal American Standard Taper Pipe ThreadsB1.20.3B
PTF SAEDryseal SAE Short Taper Pipe ThreadsB1.20.3
PTF SPLDryseal Special Short Taper Pipe ThreadsB1.20.3
PUCH BUTTButtress Threads , Push TypeB1.9
RBritish Taper Pipe ThreadsBS.21
Rc RpBritish Taper Pipe ThreadsBS.21
SGTSpecial Gage Taper ThreadsBS.21
SPL PTFDryseal Special Short Taper Pipe ThreadsB1.20.3
STUB ACMEStub Acme ThreadsB1.8
UNUnified Inch Screw Thread, Constant-Pitch SeriesB1.1
UNCUnified Inch Screw Thread, Coarse-Pitch SeriesB1.1
UNEFUnified Inch Screw Thread, Extra-Fine SeriesB1.1
UNFUnified Inch Screw Thread, Fine-Pitch SeriesB1.1
UNJUnified Inch Screw Thread, Constant-Pitch Series with Rounded Root of Radius

0.15011P to 0.18042P

B1.15
UNJEFUnified Inch Screw Thread, Fine-Pitch Series, with Rounded Root of Radius

0.15011P to 0.18042P

B1.15
UNJFUnified Inch Screw Thread, Coarse-Pitch Series, with Rounded Root of Radius

0.15011P to 0.18042P

B1.15
UNMUnified Miniature Thread SeriesB1.10
UNRUnified Inch Screw Thread, Constant-Pitch Series, with Rounded Root of Radius

Not Less Than 0.108P

B1.1
UNRCUnified Inch Screw Thread, Coarse-Pitch Series, with Rounded Root of Radius

Not Less Than 0.108P

B1.1
UNREUnified Inch Screw Thread, Extra-Fine Pitch Series, with Rounded Root of Radius

0.15011P to 0.18042P

B1.15
UNREFUnified Inch Screw Thread, Extra-Fine Pitch Series, with Rounded Root of Radius

Not Less Than 0.108P

B1.1
UNRFUnified Inch Screw Thread, Fine-Pitch Series, with Rounded Root of Radius

Not Less Than 0.108P

B1.1
UNSUnified Inch Screw Thread, Special Diameter Pitch, or Length of EngagementB1.1

COMMON THREAD NAMES AND ABBREVIATIONS

THREAD DESIGNATIONS

THREAD DESIGNATIONS
DESIGNATIONDESCRIPTION
ACME 60° STUB60° Stub thread form
ACME STUBStub Acme thread form
ACME-CAcme thread - centralizing
ACME-GAcme thread, general purpose
ANArmy and Navy thread
ANPTAeronautical National Form taper pipe thread
AWWAAmerican Water Works Association
BABritish Association Standard thread form
BSBBritish Standard Brass thread
BSCBritish Standard Cycle thread
BSFBritish Standard Fine thread series
BSPPBritish Standard Pipe Parallel
BSPTBritish Standard Pipe Taper
BSWBritish Standard Whitworth
CEICycle Engineers Institute Thread
CHTChemical Hose thread
GHTGarden Hose thread
GPIGlass Packing Institute Thread
MMISO Metric thread form
MJMetric Aerospace thread
N BUTTAmerican Buttress screw thread
NCAmerican National Coarse thread series
NEFAmerican National Extra-Fine thread series
NFAmerican National Fine thread series
NGOAmerican National gas outlet threads
NGTAmerican National gas taper threads
NHAmerican National hose & fire hose coupling
NMNational Miniature thread series
NPSAmerican Standard straight pipe thread
NPSCAmerican Standard straight pipe thread in couplings
NPSFAmerican Standard internal straight pipe thread (dryseal)
NPSHAmerican Standard straight pipe thread for hose couplings & nipples
NPSIAmerican Standard intermediate straight pipe thread (dryseal)
NPSLAmerican Standard straight pipe thread for locknuts
NPSMAmerican Standard straight pipe thread for mechanical joints
NPTAmerican Standard taper pipe thread
NPTFDryseal American Standard taper pipe thread
NPTRAmerican Standard taper pipe thread for rail fittings
NSSpecial threads of American National Form
PgPanzergewinde thread
PTFDryseal SAE Short Taper pipe thread
RMSRoyal Microscopical Society thread
SGTSpecial Gas Taper thread form
SPL-PTFDryseal Short Taper Pipe thread
STISpecial Threads for Helical Coil Wire Screw Thread Inserts
UNUnified and American thread series
UNCUnified and American Coarse thread series
UNEFUnified and American Extra-Fine thread series
UNFUnified and American Fine thread series
UNIVUnified Miniature Thread Series
UNJUnified Thread Series with Controlled Root Radius
UNJCUnified Coarse Thread Series with Controlled Root Radius
UNJFUnified Fine Thread Series with Controlled Root Radius
UNRUnified Constant Pitch thread series with Controlled Root Radius
UNRCUnified Coarse Thread Series with Controlled Root Radius
UNRFUnified Fine Thread Series with Controlled Root Radius
UNSUnified and American threads of selected special diameters and pitches
VTyre Valve thread

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