ANSI Thread Series Designation
- (1) All threads, except NGO, are right hand, unless otherwise designated. For NGO threads, designations RH or LH are required.
- (2) As published in SAE A571051
- (3) As published in Military Specification MIL-S8879, ISO 3161 and ASME B1.15.
|
| Designation |
Thread Series |
ANSI Reference |
| ACME-C |
Acme Threads, centralizing |
ASME B1.5 |
| ACME-G |
Acme threads, general purpose (see also Stub Acme) |
ASME B1.5 |
| AMO |
American Standard microscope objective threads |
ASME B1.11 |
| ANPT |
Aeronautical National Form taper pipe threads (2) |
|
| BUTT |
Buttress threads, pull type |
ASME B1.9 |
| PUSH-BUTT |
Buttress threads, push type |
ASME B1.9 |
| F-PTF |
Dryseal fine taper pipe thread series |
ASME B1.20.3 (Appendix C) |
| M |
Metric screw threads - M profile with basic ISO 68 Profile |
ASME B1.13M, ASME B1.18M |
| MJ |
Metric screw threads - MJ profile with rounded root of radius (0.15011P to 0.18042P) |
ASME B1.21M |
| MJS |
Metric screw threads - MJ profile special series |
ASME B1.21M |
| |
Class 5 interference fit external threads |
|
| NC5HF |
For driving in hard ferrous material of hardness over 160 Bhn |
ASME B1.21M |
| NC5 CSF |
For driving in copper alloy and soft ferrous material of 160 Bhn or less |
ASME B1.21M |
| NC5 ONF |
For driving in other nonferrous material (Nonferrous materials other than copper alloys), any hardness |
ASME B1.21M |
| |
Class 5 interference fit internal threads |
|
| NC5 IF |
Entire ferrous material range |
ASME B1.21M |
| NC5 INF |
Entire nonferrous material range |
ASME B1.21M |
| NGO |
National gas outlet threads (1) |
ANSI/CGA V-1 (ASME B57.1) |
| NGS |
National gas straight threads |
ANSI/CGA V-1 (ASME B57.1) |
| NGT |
National gas taper threads (see also SGT) |
ANSI/CGA-V1 (ASME B57.1) |
| NH |
American Standard hose coupling threads of full form |
ASME B2.4 (ASME B1.20.7) |
| NHR |
American Standard hose coupling threads for garden hose applications |
ASME B2.4 (ASME B1.20.7) |
| NPSC |
American Standard Straight pipe threads in pipe couplings |
ASME B1.20.1 |
| NPSF |
Dryseal American Standard fuel internal straight pipe threads |
ASME B1.20.3 |
| NPSH |
American Standard straight hose coupling threads for joining to American Standard taper pipe threads |
ASME B2.4 |
| NPSI |
Dryseal American Standard intermediate internal straight pipe threads |
ASME B1.20.3 |
| NPSL |
American Standard straight pipe threads for loose-fitting mechanical joints with locknuts |
ASME B1.20.1 |
| NPSM |
American Standard straight pipe threads for free-fitting mechanical joints with fixtures |
ASME B1.20.1 |
| NPT |
American Standard taper pipe threads for general use |
ASME B1.20.1 |
| NPTF |
Dryseal American Standard taper pipe threads |
ASME B1.20.3 |
| PTF-SAE Short |
Dryseal SAE short taper pipe threads |
ASME B1.20.3 |
| PTF-SPL Short |
Dryseal special short taper pipe threads |
ASME B1.20.3 (Appendix C) |
| S |
SO miniture screw threads .25 to 1.4mm, inclusive |
|
| SGT |
Special gas taper threads |
ANSI/CGA V-1 (ASME B57.1) |
| SPL-PTF |
Dryseal special taper pipe threads |
ASME B1.20.3 (Appendix C) |
| Stub Acme |
United inch screw thread, constant-pitch series |
ASME B1.8 |
| UN |
Unified inch screw thread, constant pitch series |
ASME B1.1 |
| UNC |
Unified inch screw thread, coarse pitch series |
ASME B1.1 |
| UNF |
Unified inch screw thread, fine pitch series |
ASME B1.1 |
| UNEF |
Unified inch screw thread, extra-fine pitch series |
ASME B1.1 |
| UNJ |
Unified inch screw thread, constant pitch series, with rounded root of radius 0.15011P to 0.18042P (3) |
|
| UNJC |
Unified inch screw thread, coarse pitch series, with rounded root of radius 0.15011P to 0.18042P (3) |
|
| UNJF |
Unified inch screw thread, fine pitch series, with rounded root of radius 0.15011P to 0.18042P (3) |
|
| UNJEF |
Unified inch screw thread, extra-fine pitch series, with rounded root of radius 0.15011P to 0.18042P (3) |
|
| UNJS |
Unified inch screw thread, special diameter, pitch or length, of engagement with rounded root radius of 0.15011P to 0.18042P (3) |
|
| UNR |
Unified inch screw thread, constant pitch series, with rounded root of radius not less than 0.108P |
ASME B1.1 |
| UNRC |
Unified inch screw thread, coarse pitch series, with rounded root of radius not less than 0.108P |
ASME B1.1 |
| UNRF |
Unified inch screw thread, fine pitch series, with rounded root of radius not less than 0.108P |
ASME B1.1 |
| UNREF |
Unified inch screw thread, extra-fine pitch series, with rounded root of radius not less than 0.108P |
ASME B1.1 |
| UNM |
Unified miniature thread series |
ASME B1.10M |
| UNS |
Unified inch screw thread, special diameter pitch or length of engagement |
ASME B1.1 |
