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.

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