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) | 12" | ... |
Pipe Outside Diameter (D) | 12.75 | 323.85 |
Pitch (TPI) (P) | 8.000 | 203.2 |
Pitch (Distance) (P) | 0.125 | 3.175 |
Thread Tapper Angle (ß) | 1.7893° | 1.7893° |
Thread V half Angle (α) | 30° | 30° |
Height of sharp V (H) | 0.108253 | 2.75 |
Thread height (h) | 0.1 | 2.54 |
Pitch Diameter at the Pipe's end (E0) | 12.53281 | 318.333 |
Minor Diameter at the Pipe's end (K0) | 12.4328 | 315.793 |
Hand-Tight Engagement Length (L1) | 1.36 | 34.544 |
Pitch Diameter at L1 plane (E1) | 12.61781 | 320.492 |
Length of Last Complete Thread (L5) | 1.875 | 47.625 |
Pitch Diameter at L5 plane (E5) | 12.65 | 321.31 |
Length of Last usefull Thread (L2) | 2.125 | 53.975 |
Pitch Diameter at L2 plane (E2) | 12.66563 | 321.707 |
Overall Thread Length (L4) | 2.5587 | 64.991 |
Length of Vanish threads (V) | 0.4338 | 11.019 |
12-8 NPT - External (pipe) Drawing
Overview Drawing
Profile Drawing
12-8 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) | 12" | ... |
Pipe Outside Diameter (D) | 12.75 | 323.85 |
Pitch (TPI) (P) | 8.000 | 203.2 |
Pitch (Distance) (P) | 0.125 | 3.175 |
Thread Tapper Angle (ß) | 1.7893° | 1.7893° |
Thread V half Angle (α) | 30° | 30° |
Height of sharp V (H) | 0.108253 | 2.75 |
Thread height (h) | 0.1 | 2.54 |
Pitch Diameter at the fitting's end (E1) | 12.61781 | 320.492 |
Length of Hand-Tight Engagemen (L1) | 1.36 | 34.544 |
Length of Wrenching Allowance (L3) |
0.25 | 6.35 |
Pitch Diameter at L3 plane (E3) | 12.51719 | 317.937 |
Tap Drill Size (T) | N/A | N/A |
12-8 NPT - Internal (Fitting) Drawing
Overview Drawing
Profile Drawing
12-8 NPT - Tolerances
Property | Minimum | Maximum |
---|---|---|
Thread Height (h) | 0.09275" (2.356 mm) | 0.1" (2.54 mm) |
L1 gage Tolerance (+/- 1 Turn) (L1) | ... | 0.125" (3.175 mm) |
Thread Truncation (f) | 0.0041" (0.104 mm) | 0.0078" (0.198 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) | " ( ) | " ( ) |