NPT threaded coupling,NPT threaded half coupling,Aluminum threaded Coupling,Stainless steel couplings
American National Standard Pipe Thread standards, often called national pipe thread standards for short, are U.S. national technical standards for screw threads used on threaded pipes and pipe fittings. They include both tapered and straight thread series for various purposes, including rigidity, pressure-tight sealing, or both.The types are named with a symbol and a full name. Examples of the symbols include NPT, NPS, NPTF, NPSC
National Standard Taper Pipe Threads Size NPT Chart – Includes both External and internal Pipe Thread Data. The taper rate for all NPT threads is 1⁄16 (3⁄4 inch per foot) measured by the change of diameter (of the pipe thread) over distance. The angle between the taper and the center axis of the pipe is 1° 47’′ 24″″ (1.7899°). Commonly-used sizes are 1/⁄8, 1/⁄4, 3/⁄8, 1⁄/2, 3⁄/4, 1, 1 1⁄/4, 1 1⁄/2, and 2 inch, appearing on pipes and fittings by most U.S. suppliers. Sizes smaller than 1/⁄8 inch are occasionally used for compressed air, while sizes larger than 2 inches are uncommon, due to the use of alternative methods of joining that are used with these larger sizes. NPT is defined by ANSI/ASME standard B1.20.1.
Nominal Pipe Size is loosely related to the inside diameter of Schedule 40 pipe. Because of the pipe wall thickness, the actual diameter of the threads is larger than the NPS, considerably so for small NPS. Other schedules of pipe have different wall thickness but the OD (outer diameter) and thread profile remain the same, so the inside diameter of the pipe is therefore different from the nominal diameter.
Related:
- Basic Dimensions, American National Standard Taper Pipe Threads, NPT
- Pitch Diameter Formulas and Calculator NPT American National Standard Taper Pipe Threads
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Notes: Reference ANSI/ASME B1.20.1-1983 (R1992) All units are in inches. |
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Outside Diameter D
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Nominal Pipe Size
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Threads per Inch (Pitch)
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Thread Pitch Length, P
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Pitch Diameter at External Thread Start E0
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Hand Tight Thread Engagement
Length, L1
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Diameter E1
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Maximum Thread Engagement L2
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Diameter E2
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0.3125
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1⁄16
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27
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0.03704
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0.27118
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0.160
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0.28118
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0.2611
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0.28750
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0.405
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1⁄8
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27
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0.03704
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0.36351
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0.1615
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0.37360
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0.2639
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0.38000
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0.540
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1⁄4
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18
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0.05556
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0.47739
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0.2278
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0.49163
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0.4018
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0.50250
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0.675
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3⁄8
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18
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0.05556
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0.61201
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0.240
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0.62701
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0.4078
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0.63750
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0.840
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1⁄2
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14
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0.07143
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0.75843
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0.320
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0.77843
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0.5337
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0.79179
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1.050
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3⁄4
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14
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0.07143
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0.96768
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0.339
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0.98887
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0.5457
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1.00179
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1.315
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1
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11 1⁄2
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0.08696
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1.21363
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0.400
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1.23863
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0.6828
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1.25630
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1.660
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1 1⁄4
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11 1⁄2
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0.08696
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1.55713
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0.420
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1.58338
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0.7068
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1.60130
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1.900
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1 1⁄2
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11 1⁄2
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0.08696
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1.79609
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0.420
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1.82234
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0.7235
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1.84130
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2.375
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2
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11 1⁄2
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0.08696
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2.26902
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0.436
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2.29627
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0.7565
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2.31630
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2.875
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2 1⁄2
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8
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0.12500
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2.71953
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0.682
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2.76216
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1.1375
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2.79062
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3.500
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3
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8
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0.12500
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3.34062
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0.766
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3.38850
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1.2000
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3.41562
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4.000
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3 1⁄2
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8
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0.12500
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3.83750
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0.821
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3.88881
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1.2500
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3.91562
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4.500
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4
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8
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0.12500
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4.33438
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0.844
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4.38712
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1.3000
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4.41562
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|
5.563
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5
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8
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0.12500
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5.39073
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0.937
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5.44929
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1.4063
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5.47862
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6.625
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6
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8
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0.12500
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6.44609
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0.958
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6.50597
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1.5125
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6.54062
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|
8.625
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8
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8
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0.12500
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8.43359
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1.063
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8.50003
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1.7125
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8.54062
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|
10.750
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10
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8
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0.12500
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10.54531
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1.210
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10.62094
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1.9250
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10.66562
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|
12.750
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12
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8
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0.12500
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12.53281
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1.360
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12.61781
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2.1250
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12.66562
|
|
14.000
|
14
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8
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0.12500
|
13.77500
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1.562
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13.87262
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2.2500
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13.91562
|
|
16.000
|
16
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8
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0.12500
|
15.76250
|
1.812
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15.87575
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2.4500
|
15.91562
|
|
18.000
|
18
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8
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0.12500
|
17.75000
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2.000
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17.87500
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2.6500
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17.91562
|
|
20.000
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20
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8
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0.12500
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19.73750
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2.125
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19.87031
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2.8500
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19.91562
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|
24.000
|
24
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8
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0.12500
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23.71250
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2.375
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23.86094
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3.2500
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23.91562
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Pipe Coupling is a very short length of pipe or tube. It has socket or female pipe threads at one or both ends. Pipe coupling allows two pipes or tubes of equal or different sizes to be joined together to make a long pipe run.
We supply the threaded pipe couplings in Aluminum and stainless steel materials.
Aluminum threaded coupling,
Stainless steel threaded couplings
Standard: ASME/ANSI B16.11, BS3799, EN ISO 4144
Size: 1/8″, 1/4″, 3/8″, 1/2″, 3/4″, 1″, 1 1/4″, 1 1/2″, 2″, 2 1/2″, 3″, 4″
Pressure Ratings: 3000 LB, 6000 LB
- NPT threaded fittings are produced to BS3799, ASTM A182 & ANSI B16.11 as applicable.
- The thread form is parallel National Pipe Thread (NPT), also know as API (American Petroleum Industry)
- They are available in four pressure ratings: 2000lb, 3000lb, 6000lb & 9000lb.
- The same range of high pressure fittings is also available with socket weld ends.
Threaded Full Couplings – 150# NPT Threaded Pipe Fittings
Class 150 full couplings are stainless steel 304 or 316 pipe fitting or aluminum with female National Pipe Taper (NPT) threads for connecting and/or extending pipes going in the same direction. These full couplings have NPT threads for creating tighter seals than straight threads.
- Use with air, water, oil, natural gas, steam
- NPT and FNPT threads conform to ASME B1.20.1
- Maximum Pressure: 300 psi @ 72 F;150 psi @ 366 F for steam
- Maximum Steam Pressure: 150 psi
