๐Ÿ”ฉ Thread Standards Reference

ISO Metric (DIN 13)  |  Trapezoidal Tr (DIN 103)  |  Whitworth BSW  |  Pipe G (ISO 228)

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dโ‚‚ = pitch diameter = d โˆ’ 0.6495ยทp  |  dโ‚ = minor diameter = d โˆ’ 1.2269ยทp  |  As = ฯ€/4ยท(d โˆ’ 0.9382ยทp)ยฒ  |  Standard: ISO 261 / DIN 13-1 to 13-11  |  60ยฐ thread angle

ISO Metric thread dimensions

Thread d (mm) Pitch (mm) dโ‚‚ (mm) dโ‚ (mm) As (mmยฒ) Hex AF (mm) Allen (mm)
dโ‚‚ = d โˆ’ 0.5ยทp  |  dโ‚ƒ = d โˆ’ p (screw minor โˆ…)  |  As = ฯ€/4ยท((dโ‚‚ + dโ‚ƒ)/2)ยฒ  |  Standard: DIN 103 / ISO 2901โ€“2905  |  30ยฐ thread angle

Trapezoidal thread dimensions (DIN 103)

Thread d (mm) Pitch (mm) dโ‚‚ (mm) dโ‚ƒ (mm) As (mmยฒ)
dโ‚‚ = d โˆ’ 0.6403ยทp  |  dโ‚ = d โˆ’ 1.2806ยทp  |  As = ฯ€/4ยท((dโ‚‚ + dโ‚)/2)ยฒ  |  Standard: BS 84 / ISO 228 (form)  |  55ยฐ thread angle  |  p = 25.4/TPI mm

Whitworth BSW thread dimensions

Thread d (mm) TPI Pitch (mm) dโ‚‚ (mm) dโ‚ (mm) As (mmยฒ)
Cylindrical (parallel) pipe thread  |  55ยฐ Whitworth thread form  |  dโ‚‚ = d โˆ’ 0.6403ยทp  |  dโ‚ = d โˆ’ 1.2806ยทp  |  Standard: ISO 228-1 / DIN ISO 228  |  Nominal size โ‰  actual diameter

Pipe G thread dimensions (ISO 228)

Thread d (mm) TPI Pitch (mm) dโ‚‚ (mm) dโ‚ (mm) As (mmยฒ)
Note: d is the actual outside diameter of the threaded part, not the nominal pipe bore size. G1 means nominally 1" pipe, but OD = 33.249 mm.