What is the OD of 1/8 NPT pipe?

0.405
Basic Dimensions, American National Standard Taper Pipe Threads, NPT, (ANSI B2. 1-1968)

Nominal Pipe Size Outside Diameter of Pipe Threads per Inch
1/16 0.313 27
1/8 0.405 27
1/4 0.540 18
3/8 0.675 18

What is the difference between NPT and BSP?

NPT/NPS threads have a 60° angle and have flattened peaks and valleys (Sellers thread form) where as BSP threads have a 55° angle and have rounded peaks and valleys (Whitworth thread form).

How do you measure BSP fittings?

Once you have the thread size, you then need to determine the number of threads per inch to verify that it is a BSP fitting. You can do this by counting the number of thread crests over a 1/4″ length and then multiply this by 4 to get the number of threads per inch.

What is the diameter of 1/8 BSP?

9.7 mm
British Standard Pipe Thread (BSPT)

BSP Thread Size Outside Diameter mm / inch TPI
1/8 Inch BSP 9.7 mm / 0.383″ 28
1/4 Inch BSP 13.16 mm / 0.518″ 19
3/8 Inch BSP 16.66 mm / 0.656″ 19
1/2 Inch BSP 20.99 mm / 0.825″ 14

Can you use NPT with BSP?

NPT/NPS and BSP threads are not compatible due to the differences in their thread forms, and not just the fact that most sizes have a different pitch.

What is the correct BSP inch size for a dash size?

How to Measure Your BSP Fittings

BSP Thread Size Outside Diameter mm / inch TPI
1 Inch BSP 33.25 mm / 1.309″ 11
1-1/4 Inch BSP 41.91 mm / 1.650″ 11
1-1/2 Inch BSP 47.80 mm / 1.882″ 11
2 Inch BSP 59.61 mm / 2.347″ 11

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