ISO OR ANSI THREAD DESIGNATIONS

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

ISO or ANSI
Designation
DESCRIPTION Ref. ANSI, BS, ISO
ACME C Acme Threads, Centralizing B1.5
ACME G Acme Threads, General Purpose B1.5
AMO American Standard Microscope Objective Threads B1.11
ANPT Dryseal Special Taper Pipe Threads B1.20.3
AWWA Underground Service Line Valves and Fittings C800-84
BA British Screw Threads BS.57
BSF British Parallel Screw Threads BS.84
BSW British Parallel Screw Threads BS.84
BUTT Buttress Threads, Pull Type B1.9
DIN German Specifications -
F-PTF Dryseal Fine Taper Threads Series B1.20.3
G Straight Pipe Threads BS.2779
ISO International Standard Organization -
JIS Japanese Industrial Standard -
M Metric Screw Threads-M Profile with Basic ISO 68 Profile B1.13M B1.18M
MJ Metric Screw Threads-MJ Profile with Rounded Root of Radius 0.15011P to 0.18042P B1.21M
MJS Metric Screw Threads-MJ Profile Special Series B1.21M
NC5 Class 5 Interference Fit External Threads B1.12
NC5 Class 5 Interference Fit Internal Threads B1.12
NC5 IF Entire Ferrous Material Range B1.12
NC5CSF For Driving Copper Alloy and Soft Ferrous Material of 160 Bhn or Less B1.12
NC5HF For Driving in Hard Ferrous Material of Hardness over 160 Bhn B1.12
NC5ONF For Driving in Other NonFerrous Material (Nonferrous Materials Other Than
Copper Alloys, Any Hardness
B1.12
NCF INF Entire Nonferrous Material Range B1.12
NFPA 1963 Fire Hose Threads -
NGO National Gas Outlet Threads CGA V-1
NGS National Gas Straight Threads CGA V-1
NGT National Gas Taper Threads (See Also SGT) CGA V-1
NH American Standard Hose Coupling Threads of Full Form B1.20.7
NHR American Standard Hose Coupling Threads for Garden Hose Applications B1.20.7
NPSC American Standard Straight Pipe Threads in Pipe Couplings B1.20.1
NPSF Dryseal American Standard Fuel Internal Straight Pipe Threads B1.20.3
NPSH Dryseal American Standard for Hose Coupling Joints with Straight Internal
External Loose Fitting Thread
B1.20.7
NPSI Dryseal American Standard Intermediate Internal Straight Pipe Threads B1.20.3
NPSL Aeronautical National Form Taper Pipe Threads MIL P-7105B
NPSM American Standard Straight Pipe Threads for Free-Fitting Mechanical
Joints for Fixtures
B1.20.1
NPT American Standard Taper Pipe Threads for General Use B1.20.3
NPTF Dryseal American Standard Taper Pipe Threads B1.20.3B
PTF SAE Dryseal SAE Short Taper Pipe Threads B1.20.3
PTF SPL Dryseal Special Short Taper Pipe Threads B1.20.3
PUCH BUTT Buttress Threads , Push Type B1.9
R British Taper Pipe Threads BS.21
Rc Rp British Taper Pipe Threads BS.21
SGT Special Gage Taper Threads BS.21
SPL PTF Dryseal Special Short Taper Pipe Threads B1.20.3
STUB ACME Stub Acme Threads B1.8
UN Unified Inch Screw Thread, Constant-Pitch Series B1.1
UNC Unified Inch Screw Thread, Coarse-Pitch Series B1.1
UNEF Unified Inch Screw Thread, Extra-Fine Series B1.1
UNF Unified Inch Screw Thread, Fine-Pitch Series B1.1
UNJ Unified Inch Screw Thread, Constant-Pitch Series with Rounded Root of Radius
0.15011P to 0.18042P
B1.15
UNJEF Unified Inch Screw Thread, Fine-Pitch Series, with Rounded Root of Radius
0.15011P to 0.18042P
B1.15
UNJF Unified Inch Screw Thread, Coarse-Pitch Series, with Rounded Root of Radius
0.15011P to 0.18042P
B1.15
UNM Unified Miniature Thread Series B1.10
UNR Unified Inch Screw Thread, Constant-Pitch Series, with Rounded Root of Radius
Not Less Than 0.108P
B1.1
UNRC Unified Inch Screw Thread, Coarse-Pitch Series, with Rounded Root of Radius
Not Less Than 0.108P
B1.1
UNRE Unified Inch Screw Thread, Extra-Fine Pitch Series, with Rounded Root of Radius
0.15011P to 0.18042P
B1.15
UNREF Unified Inch Screw Thread, Extra-Fine Pitch Series, with Rounded Root of Radius
Not Less Than 0.108P
B1.1
UNRF Unified Inch Screw Thread, Fine-Pitch Series, with Rounded Root of Radius
Not Less Than 0.108P
B1.1
UNS Unified Inch Screw Thread, Special Diameter Pitch, or Length of Engagement B1.1

COMMON THREAD NAMES AND ABBREVIATIONS

THREAD DESIGNATIONS

THREAD DESIGNATIONS
DESIGNATION DESCRIPTION
ACME 60° STUB 60° Stub thread form
ACME STUB Stub Acme thread form
ACME-C Acme thread - centralizing
ACME-G Acme thread, general purpose
AN Army and Navy thread
ANPT Aeronautical National Form taper pipe thread
AWWA American Water Works Association
BA British Association Standard thread form
BSB British Standard Brass thread
BSC British Standard Cycle thread
BSF British Standard Fine thread series
BSPP British Standard Pipe Parallel
BSPT British Standard Pipe Taper
BSW British Standard Whitworth
CEI Cycle Engineers Institute Thread
CHT Chemical Hose thread
GHT Garden Hose thread
GPI Glass Packing Institute Thread
MM ISO Metric thread form
MJ Metric Aerospace thread
N BUTT American Buttress screw thread
NC American National Coarse thread series
NEF American National Extra-Fine thread series
NF American National Fine thread series
NGO American National gas outlet threads
NGT American National gas taper threads
NH American National hose & fire hose coupling
NM National Miniature thread series
NPS American Standard straight pipe thread
NPSC American Standard straight pipe thread in couplings
NPSF American Standard internal straight pipe thread (dryseal)
NPSH American Standard straight pipe thread for hose couplings & nipples
NPSI American Standard intermediate straight pipe thread (dryseal)
NPSL American Standard straight pipe thread for locknuts
NPSM American Standard straight pipe thread for mechanical joints
NPT American Standard taper pipe thread
NPTF Dryseal American Standard taper pipe thread
NPTR American Standard taper pipe thread for rail fittings
NS Special threads of American National Form
Pg Panzergewinde thread
PTF Dryseal SAE Short Taper pipe thread
RMS Royal Microscopical Society thread
SGT Special Gas Taper thread form
SPL-PTF Dryseal Short Taper Pipe thread
STI Special Threads for Helical Coil Wire Screw Thread Inserts
UN Unified and American thread series
UNC Unified and American Coarse thread series
UNEF Unified and American Extra-Fine thread series
UNF Unified and American Fine thread series
UNIV Unified Miniature Thread Series
UNJ Unified Thread Series with Controlled Root Radius
UNJC Unified Coarse Thread Series with Controlled Root Radius
UNJF Unified Fine Thread Series with Controlled Root Radius
UNR Unified Constant Pitch thread series with Controlled Root Radius
UNRC Unified Coarse Thread Series with Controlled Root Radius
UNRF Unified Fine Thread Series with Controlled Root Radius
UNS Unified and American threads of selected special diameters and pitches
V Tyre Valve thread