3/4-11.5 NH NH (hose coupling) External Thread Specifications
3/4-11.5NH EXT
ASMESTD: ASME B1.20.7SOURCE: Table 2 · p. 5TYPE: External (bolt/screw)CLASS: StdSERIES: NH (hose coupling)
Major diameter
1.0625 – 1.0455
max – min
Pitch diameter
1.0060 – 0.9975
max – min
Minor diameter
0.9495 – 0.9285
max – min
Pitch
0.08696
11.5 threads per inch
Thread profile
3/4-11.5NH EXT: solid line = maximum material profile, dashed = minimum material, hatched = tolerance zone, grey dashed = basic profile. Drawn to scale; values in inches, diameters shortened.
Limits of size, class Std
| Dimension | Basic | Max | Min | Tolerance |
|---|---|---|---|---|
| Major diameter dPara. 3.1: tolerance = 2 × PD tolerance | 1.0725 | 1.0625 | 1.0455 | 0.0170 |
| Pitch diameter d2 | 1.0160 | 1.0060 | 0.9975 | 0.0085 |
| Minor diameter d1Max printed; min is a reference value | 0.9595 | 0.9495 | 0.9285ref. | 0.0211ref. |
| Allowance es | 0.0100 |
Dimensions in inches. Values are those of the standard (ASME B1.20.7); calculated cells follow the standard’s formulas. Where the standard prints a value that differs from its formula, the printed value is shown with a note.
Tolerance zones relative to the basic size, inches
Mating, gaging and dimensions
Mating member and fit at the limits
- Service
- Garden hose
- Mating group (compatible designations)
- GH-3/4-11.5
- Mating member of the same designation
- 3/4-11.5NH INT
- Other designations in the mating group
- 3/4-11.5NHR
- Minimum PD clearance (coupling min − nipple max)
- 0.0100 in
- Maximum PD clearance (coupling max − nipple min)
- 0.0270 in
- Minimum major dia clearance
- 0.0100 in
- Minimum minor dia clearance
- 0.0100 in
- Fit at the limits (PD)
- clearance (always)
Lead, flank and profile
- Lead variation ± (Table 5) ±δP
- 0.0025 in
- Half-angle variation ± (Table 5) ±δα
- 1° 52′
- Lead angle at the basic PD λ
- 1° 34′
- Crest flat (basic P/8)
- 0.010870 in
- Root flat (basic P/8)
- 0.010870 in
- Extreme flat P/24 at minimum PD
- 0.003623 in
- Root radius for the model (worn tool) r
- 0.009413 in
Table 4 dimensions (nipple and coupling)
- As printed
- C 25/32; OD 1 1/16; L 9/16; l 1/8
- Inside diameter of the nipple C
- 0.78125 in
- Approximate OD of the external thread OD
- 1.06250 in
- Length of the nipple L
- 0.56250 in
- Pilot length l
- 0.12500 in
Ring gages (Table 6)
- GO pitch max / min
- 1.0060 / 1.0057 in
- GO minor max / min
- 0.9595 / 0.9589 in
- NOT GO pitch max / min
- 0.9978 / 0.9975 in
- NOT GO minor max / min
- 0.9793 / 0.9787 in
- Z GO major max / min
- 1.06250 / 1.06238 in
- Z NOT GO major max / min
- 1.04562 / 1.04550 in
Setting plugs (Table 8) and plug gages (Table 7)
- GO truncated major max / min
- 1.0492 / 1.0486 in
- GO full major max / min
- 1.0631 / 1.0625 in
- GO pitch max / min
- 1.0060 / 1.0057 in
- NOT GO truncated major max / min
- 1.0352 / 1.0346 in
- NOT GO pitch max / min
- 0.9978 / 0.9975 in
Notes
- Garden hose sizes 1/2, 5/8 and 3/4 use this thread. Root radius and tensile stress area are not given in the standard.
Mates
3/4-11.5NH EXT screws into a thread of the same standard at the same size and pitch. The standard mating internal thread is class Std. Check the fit with the standard pair →
Working out the mating options…
Different pitch or a different thread family never mate; the fit check runs over both tolerance zones.
Related thread sizes
Same diameter other pitch, and neighbouring sizes
All values for 3/4-11.5NH EXTevery column of the workbook row
| Designation | 3/4-11.5NH EXT |
|---|---|
| Decimal / alternate designation | 0.7500-11.5NH EXT |
| Threads per inch | 11.5 |
| Thread form | NH |
| Series | GH |
| Series name | Garden hose |
| External / internal | External |
| Class | Std |
| Nominal size of hose | 1/2, 5/8, 3/4 |
| Pitch P (in.) | 0.08696 |
| Basic major dia D (in.) | 1.0725 |
| Size category | Standard sizes (Tables 1-8) |
| Source table | Table 2 |
| Printed page | 5 |
| Major dia max (in.) | 1.0625 |
| Major dia min (in.) | 1.0455 |
| Major dia tolerance (in.) | 0.0170 |
| Allowance es (in.) | 0.0100 |
| Basic pitch dia D2 (in.) | 1.0160 |
| Pitch dia max (in.) | 1.0060 |
| Pitch dia min (in.) | 0.9975 |
| PD tolerance (in.) | 0.0085 |
| Basic minor dia D1 (in.) | 0.9595 |
| Minor dia max (in.) | 0.9495 |
| Minor dia min (in.) | 0.9285 |
| Minor dia tolerance (in.) | 0.0211 |
| Major dia status | Toleranced (para. 3.1: tolerance = 2 x PD tolerance) |
| Minor dia status | Maximum printed; minimum is a reference value (para. 3.1: P/24 flat at min PD) |
| Root radius max (in.) | not given in the standard |
| Root radius min (in.) | not given in the standard |
| Lead variation ± (in.) (Table 5) | 0.0025 |
| Half-angle variation ± (Table 5) | 1° 52′ |
| Lead variation from PD tol (calc) (in.) | 0.0025 |
| Half-angle variation from PD tol (calc) | 1° 52′ |
| Lead angle at basic PD (deg) | 1.5605 |
| Lead angle (deg min) | 1° 34′ |
| Tensile stress area As (sq in.) | not given in the standard |
| Thread angle (deg) | 60 |
| Flank angle (deg) | 30 |
| Sharp V height H (in.) | 0.075307 |
| Thread height h (in.) | 0.056480 |
| Crest flat, basic P/8 (in.) | 0.010870 |
| Root flat, basic P/8 (in.) | 0.010870 |
| Extreme flat P/24 at minimum PD (in.) | 0.003623 |
| Truncation of the P/8 flat from the sharp V, f = h/6 (in.) | 0.009413 |
| Root radius for model (worn tool) (in.) | 0.009413 |
| Sweep cut: start diameter (in.) | 1.062500 |
| Sweep cut: tip diameter (in.) | 0.949500 |
| Sweep cut: depth (in.) | 0.056500 |
| Sweep cut: profile width at start diameter (in.) | 0.076110 |
| Crest flat as modelled (in.) | 0.010847 |
| Taper | none (straight thread) |
| Service | Garden hose |
| Mating group (compatible designations) | GH-3/4-11.5 |
| Mating member of the same designation | 3/4-11.5NH INT |
| Other designations in the mating group | 3/4-11.5NHR |
| Min PD clearance: coupling min PD - nipple max PD (in.) | 0.0100 |
| Max PD clearance: coupling max PD - nipple min PD (in.) | 0.0270 |
| Min major dia clearance: coupling min - nipple max (in.) | 0.0100 |
| Min minor dia clearance: coupling min - nipple max (in.) | 0.0100 |
| Fit at the limits (PD) | clearance (always) |
| Table 4 lengths as printed | C 25/32; OD 1 1/16; L 9/16; l 1/8 |
| Table 4: C inside dia of nipple (in.) | 0.78125 |
| Table 4: approx OD of external thread (in.) | 1.06250 |
| Table 4: L length of nipple (in.) | 0.56250 |
| Table 4: l pilot length (in.) | 0.12500 |
| Table 6 ring gage: GO pitch max (in.) | 1.0060 |
| Table 6 ring gage: GO pitch min (in.) | 1.0057 |
| Table 6 ring gage: GO minor max (in.) | 0.9595 |
| Table 6 ring gage: GO minor min (in.) | 0.9589 |
| Table 6 ring gage: NOT GO pitch max (in.) | 0.9978 |
| Table 6 ring gage: NOT GO pitch min (in.) | 0.9975 |
| Table 6 ring gage: NOT GO minor max (in.) | 0.9793 |
| Table 6 ring gage: NOT GO minor min (in.) | 0.9787 |
| Table 6 ring gage: Z GO major max (in.) | 1.06250 |
| Table 6 ring gage: Z GO major min (in.) | 1.06238 |
| Table 6 ring gage: Z NOT GO major max (in.) | 1.04562 |
| Table 6 ring gage: Z NOT GO major min (in.) | 1.04550 |
| Table 8 setting plug: GO truncated major max (in.) | 1.0492 |
| Table 8 setting plug: GO truncated major min (in.) | 1.0486 |
| Table 8 setting plug: GO full major max (in.) | 1.0631 |
| Table 8 setting plug: GO full major min (in.) | 1.0625 |
| Table 8 setting plug: GO pitch max (in.) | 1.0060 |
| Table 8 setting plug: GO pitch min (in.) | 1.0057 |
| Table 8 setting plug: NOT GO truncated major max (in.) | 1.0352 |
| Table 8 setting plug: NOT GO truncated major min (in.) | 1.0346 |
| Table 8 setting plug: NOT GO full major max (in.) | 1.0631 |
| Table 8 setting plug: NOT GO full major min (in.) | 1.0625 |
| Table 8 setting plug: NOT GO pitch max (in.) | 0.9978 |
| Table 8 setting plug: NOT GO pitch min (in.) | 0.9975 |
| Table 8 setting plug: Full-form GO major max (in.) | 1.0631 |
| Table 8 setting plug: Full-form GO major min (in.) | 1.0625 |
| Table 8 setting plug: Full-form NOT GO major max (in.) | 1.0631 |
| Table 8 setting plug: Full-form NOT GO major min (in.) | 1.0625 |
| Check against formulas | OK |
| Notes | Garden hose sizes 1/2, 5/8 and 3/4 use this thread. Root radius and tensile stress area are not given in the standard. |
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ASME B1.20.7: Hose Coupling Screw Threads, Inch. Source: workbook data (2026-10-10). Confirm against your licensed copy of the standard before use.