Thread Parameters
in
tpi
%
in
Thread Specifications
Basic Geometry
Pitch:
0.0769 in
Lead:
0.0769 in
Lead Angle:
2.34° (2° 20')
Thread Angle:
60.0°
Thread Depths
External (Bolt) Single / Double:
0.0472 / 0.0944 in
Internal (Nut) Single / Double:
0.0416 / 0.0833 in
Radial Infeed (Single depth):
0.0472 in
Tool Profile Flats
External Crest Width:
0.0096 in
External Root Width:
0.0192 in
Internal Crest Width:
0.0192 in
Internal Root Width:
0.0096 in
ASME B1.1 Tolerance Limits
| Diameter | Basic | External Max / Min | Internal Min / Max |
|---|---|---|---|
| Major | 0.5000 | 0.4985 / 0.4876 | 0.5000 / Min |
| Pitch | 0.4500 | 0.4485 / 0.4435 | 0.4500 / 0.4552 |
| Minor | 0.4001 | 0.3986 / Max | 0.4172 / 0.4340 |
3-Wire Measurement
Suggested Best Wire:
0.0444 in
Measurement Over Wires (Max):
0.5168 in
Measurement Over Wires (Median):
0.5152 in
Measurement Over Wires (Min):
0.5118 in
Tapping & Die Preparation
Die Blank Outer Dia:
0.4923 in
Suggested Drill (Calculated):
0.4231 in
Standard Drills (8 Close):
Thread Depth Percentage:
75% thread
Pipe Thread Parameters
in
Pipe Thread Specifications
Thread Series Profile
Series:
NPSM
Standard Document:
ANSI/ASME B1.20.1
Thread Angle / Pitch:
60° / 0.0370 in (27 TPI)
Joint Sealing Method:
Non-pressure tight.
Dimensional Limits (Min / Max)
| Diameter | External (Male) Limits | Internal (Female) Limits |
|---|---|---|
| Major (OD) | - | - |
| Pitch (PD) | - | - |
| Minor (ID) | - | - |
Tapping Drill Suggestion
Suggested Drill Size:
-
Note: Parallel pipe threads use standard lookup drills rather than calculated percentages due to fixed standard envelope boundaries.
3-Wire Measurement Over Wires
Best Wire Size (Ideal):
-
Actual Wire Used:
-
Measurement Max:
-
Measurement Median:
-
Measurement Min:
-
Parallel Pipe Thread Reference Guide
Parallel (straight) pipe threads have a constant diameter along the entire length of the thread. Unlike tapered pipe threads (such as NPT or BSPT), parallel threads do not seal on the thread flanks (with the exception of NPSF fuel threads). Assembly relies on secondary seal features like gaskets, O-rings, or conical metal seats.
| Series | Standard | Thread Angle | Primary Sealing Interface | Machining Application |
|---|---|---|---|---|
| NPSM | ANSI/ASME B1.20.1 | 60° | 30° conical metal seat (swivel nut fittings) | Mechanical free-fitting ports |
| NPSL | ANSI/ASME B1.20.1 | 60° | Locknut mechanical compression with flat gasket | Loose locknut fastening joints |
| NPSH | ANSI/ASME B1.20.7 | 60° | Elastomeric compression washer inside coupling | Steam, air, and liquid hose couplings |
| NPSF | ANSI/ASME B1.20.3 | 60° | Crest-to-root interference crush with NPTF male | Dryseal fuel, oil, and gas ports |
| BSPP (G) | ISO 228-1 | 55° | O-ring chamfer gland or flat bonded washer seal | International hydraulics and fluid fittings |
Hydraulic Fitting Selector
%
in
Fitting Seal Profile
Seat Profile:
-
Working Pressure:
-
Thread Specification:
-
Thread Specifications
Basic Geometry
Pitch:
-
Lead:
-
Lead Angle:
-
Thread Angle:
-
Thread Depths
External (Bolt) Single / Double:
-
Internal (Nut) Single / Double:
-
Radial Infeed (Single depth):
-
Tool Profile Flats
External Crest Width:
-
External Root Width:
-
Internal Crest Width:
-
Internal Root Width:
-
Dimensional Limits (Min / Max)
| Diameter | Basic Size | External Min / Max | Internal Min / Max |
|---|---|---|---|
| Major (OD) | - | - | - |
| Pitch (PD) | - | - | - |
| Minor (ID) | - | - | - |
3-Wire Measurement
Best Wire Size (Ideal):
-
Measurement Over Wires (Max):
-
Measurement Over Wires (Median):
-
Measurement Over Wires (Min):
-
Tapping Drill Suggestions
Calculated Size (Target):
-
Closest standard drills:
Drill Thread Depth %:
-
Bi-Directional Wire Math
Calculation Result
Calculated Measurement (M)
0.5168
inches
Formula used:
M = E + W * (1 + csc(alpha)) - (P / 2) * cot(alpha)