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