Pipe Thread data sheet


External (pipe) Basic Thread Dimensions

For interpertations of the terms scroll down to the drawings below the table

Property Inch mm
Nominal Pipe Size (Ø) 1 1/2" ...
Pipe Outside Diameter (D) 1.9 48.26
Pitch (TPI) (P) 11.500 292.1
Pitch (Distance) (P) 0.08695652 2.209
Thread Tapper Angle (ß) 1.7893° 1.7893°
Thread V half Angle (α) 30° 30°
Height of sharp V (H) 0.075307 1.913
Thread height (h) 0.06957 1.767
Pitch Diameter at the Pipe's end (E0) 1.79609 45.621
Minor Diameter at the Pipe's end (K0) 1.7265 43.853
Hand-Tight Engagement Length (L1) 0.42 10.668
Pitch Diameter at L1 plane (E1) 1.82234 46.287
Length of Last Complete Thread (L5) 0.5496 13.96
Pitch Diameter at L5 plane (E5) 1.83043 46.493
Length of Last usefull Thread (L2) 0.7235 18.377
Pitch Diameter at L2 plane (E2) 1.8413 46.769
Overall Thread Length (L4) 1.0252 26.04
Length of Vanish threads (V) 0.3017 7.663

1 1/2-11.5 NPT - External (pipe) Drawing

Overview Drawing

Profile Drawing

1 1/2-11.5 NPT - Internal (Fitting) Basic Thread Dimensions

For interpertations of the terms scroll down to the drawings below the table

Property Inch mm
Nominal Pipe Size (Ø) 1 1/2" ...
Pipe Outside Diameter (D) 1.9 48.26
Pitch (TPI) (P) 11.500 292.1
Pitch (Distance) (P) 0.08695652 2.209
Thread Tapper Angle (ß) 1.7893° 1.7893°
Thread V half Angle (α) 30° 30°
Height of sharp V (H) 0.075307 1.913
Thread height (h) 0.06957 1.767
Pitch Diameter at the fitting's end (E1) 1.82234 46.287
Length of Hand-Tight Engagemen (L1) 0.42 10.668

Length of Wrenching Allowance (L3)

0.2609 6.627
Pitch Diameter at L3 plane (E3) 1.77978 45.206
Tap Drill Size (T) 1.7344 44.054

1 1/2-11.5 NPT - Internal (Fitting) Drawing

Overview Drawing

Profile Drawing

1 1/2-11.5 NPT - Tolerances

Property Minimum Maximum
Thread Height (h) 0.06261" (1.59 mm) 0.06957" (1.767 mm)
L1 gage Tolerance (+/- 1 Turn) (L1) ... 0.08696" (2.209 mm)
Thread Truncation (f) 0.0029" (0.074 mm) 0.0063" (0.16 mm)
Tapper angle Variation (ß) 1.641" ( ) 2.089" ( )
Thead V Half Angle (+/-) (α) ... 0.75" ( )
Thread Height (h) " (0 mm) " (0 mm)
L1 gage Tolerance (+/- 1 Turn) (L1) " ( ) " ( )
Thread Truncation (f) " (0 mm) " (0 mm)
Tapper angle Variation (ß) " ( ) " ( )
Thead V Half Angle (+/-) (α) " ( ) " ( )
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