Thread Fittings
Thread may be the first connection method of piping system, it is similar to Socket Weld Pipe Fittings. ASME B16.11 NPT Fittings is usually used in nominal diameter of DN100 and below.
The vertebral tube thread is stipulated the threads per inch, the pitch diameter and screw length in the ASME B1.20.1.
Threaded steel pipe fittings are usually used for low cost and less demand. For example: domestic water, fire fighting pipeline and industrial cooling system.
Free Download: ASME B16.11-2011 Standard (Full Text PDF)
Steel Fittings Material
The materials are usually include gray cast iron or malleable irons, cast brass or bronze, forged alloys, carbon steel or stainless steel materials. Like 3/4” Threaded Coupling SS316, 1” Threaded Cap A105N, 1 1/2” Threaded Pipe Elbow A350 LF2 CL1 and so on.
ASME Steel Fitting Pressure
There are three pressure rate of ASME B16.11 NPT Fittings, Class 2000, Class 3000, Class 6000.
What are called Threaded Fittings
We called 45 Deg Threaded Elbow, 90 Deg Threaded Elbow, Threaded Tee, Threaded Coupling, Threaded Cap, Square Head Plug, Hex Head Plug, Round Head Bushing, Hex Head Bushing, Flushing Bushing, Hexagonal Nipple and Swaged Nipple as ASME B16.11 NPT Fittings.
ASME B16.11 NPT Fittings
It uses NTP in the ASME B16.11 standard. That means the vertebral tube thread in the ASME B1.20.1, which is the most commonly used mechanical connection and hydraulic seal thread. The NPT female and male threads are tapered with PTFE or sealant seals
|
DN-NPT |
Pipe Diameter |
Diameter of Tapping mm |
Threads per Inch TPI |
Pitch |
|---|---|---|---|---|
|
mm |
mm | |||
|
1/16″ | 7.895 | 6 | 27 | 0.941 |
| 1/8″ | 10.242 | 8.25 | 27 |
0.941 |
|
1/4″ | 13.616 | 10.7 | 18 | 1.411 |
|
3/8″ | 17.055 | 14.1 | 18 | 1.411 |
| 1/2″ | 21.223 | 17.4 | 14 |
1.814 |
| 3/4″ | 26.568 | 22.6 | 14 |
1.814 |
|
1″ | 33.228 | 28.5 | 11.5 | 2.209 |
| 1.1/4″ | 41.985 | 37 | 11.5 |
2.209 |
|
1.1/2″ | 48.054 | 43.5 | 11.5 | 2.209 |
| 2″ | 60.092 | 55 | 11.5 |
2.209 |
|
2.1/2″ | 72.699 | 65.5 | 8 | 3.175 |
| 3″ | 88.608 | 81.5 | 8 |
3.175 |
|
3.1/2″ | 101.316 | 94.3 | 8 | 3.175 |
| 4″ | 113.973 | 107 | 8 |
3.175 |
|
5″ | 141.3 | 134.384 | 8 | 3.175 |
| 6″ | 168.275 | 161.191 | 8 |
3.175 |
|
8″ | 219.075 | 211.673 | 8 | 3.175 |
| 10″ | 273.05 | 265.311 | 8 |
3.175 |
|
12″ | 323.85 | 315.793 | 8 |
3.175 |

90 Deg Threaded Elbow
Threaded Tee
Screwed Cross Tee
45 Deg Threaded Elbow

Threaded Coupling
Threaded Cap
Square Head Plug
Hex Head Plug
Round Head Bushing

Hex Head Bushing
Threaded Union
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