3/4-11.5 NHR NHR (hose coupling, reduced) External Thread Specifications
3/4-11.5NHR EXT
ASMESTD: ASME B1.20.7SOURCE: Table 2 · p. 5TYPE: External (bolt/screw)CLASS: StdSERIES: NHR (hose coupling, reduced)
Major diameter
1.0520 – 1.0350
max – min
Pitch diameter
0.0100 – 0.9930
max – min
Minor diameter
0.9495 – not given in the standard
max – min
Pitch
0.08696
11.5 threads per inch
Thread profile
No standard mating class is given for this pitch.
: 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 | 1.0680 | 1.0520 | 1.0350 | 0.0170 |
| Pitch diameter d2 | 1.0160 | 0.0100 | 0.9930 | 0.0170 |
| Minor diameter d1Max printed; min is a reference value | 0.9720 | 0.9495 | not given in the standardref. | not given in the standardref. |
| Allowance es | 0.0160 |
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.
Mating, gaging and dimensions
Mating member and fit at the limits
- Service
- Garden hose formed thread
- Mating group (compatible designations)
- GH-3/4-11.5
- Mating member of the same designation
- 3/4-11.5NHR INT
- Other designations in the mating group
- 3/4-11.5NH
- Minimum PD clearance (coupling min − nipple max)
- 1.0060 in
- Maximum PD clearance (coupling max − nipple min)
- 0.0350 in
- Minimum major dia clearance
- 0.0160 in
- Minimum minor dia clearance
- 0.0225 in
- Fit at the limits (PD)
- clearance (always)
Lead, flank and profile
- Lead variation ± (Table 5) ±δP
- 0.0049 in
- Half-angle variation ± (Table 5) ±δα
- 3° 44′
- 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
- 1.0100 / 1.0097 in
- GO minor max / min
- 0.9720 / 0.9726 in
- NOT GO pitch max / min
- 0.9933 / 0.9930 in
- NOT GO minor max / min
- 0.9748 / 0.9742 in
- Z GO major max / min
- 1.05200 / 1.05188 in
- Z NOT GO major max / min
- 1.03512 / 1.03500 in
Setting plugs (Table 8) and plug gages (Table 7)
- GO truncated major max / min
- 1.0387 / 1.0381 in
- GO full major max / min
- 1.0526 / 1.0520 in
- GO pitch max / min
- 1.0100 / 1.0097 in
- NOT GO truncated major max / min
- 1.0307 / 1.0301 in
- NOT GO pitch max / min
- 0.9933 / 0.9930 in
Notes
- Printed value kept. Misprint: Table 1 col 7 (p. 4), 3/4-11.5NHR, printed allowance 0.0160; expected 0.0060 (coupling PD min 1.0160 - nipple PD max 1.0100). Printed value kept. Misprint: Table 2 col 10 (p. 5), 3/4-11.5NHR, printed nipple pitch dia max 0.0100; expected 1.0100 (Table 1 col 9 and Table 6 col 5 print 1.0100). Printed value kept. Misprint: Table 6 col 6 (p. 9), 3/4-11.5NHR, printed GO minor-dia ring gage max 0.9720 / min 0.9726; expected min 0.9714 (min must be below max for a minus tolerance). NHR (formed thread) is excluded from paras. 3.1 and 3.2: tolerances and minimum/maximum values are the printed table values. 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.
- Allowance (coupling min PD - nipple max PD): printed 0.0160, formula 0.0060 | PD tolerance = max - min: printed 0.0170, formula -0.9830 | Table 1 col 7 (p. 4), 3/4-11.5NHR: printed allowance 0.0160; expected 0.0060 (coupling PD min 1.0160 - nipple PD max 1.0100) | Table 2 col 10 (p. 5), 3/4-11.5NHR: printed nipple pitch dia max 0.0100; expected 1.0100 (Table 1 col 9 and Table 6 col 5 print 1.0100) | Table 6 col 6 (p. 9), 3/4-11.5NHR: printed GO minor-dia ring gage max 0.9720 / min 0.9726; expected min 0.9714 (min must be below max for a minus tolerance) | NHR is excluded from paras. 3.1 and 3.2, so its basic/limit values are the table values and differ from D - h, D - 2h by definition (Basic pitch diameter (D - h) printed 1.0160 vs 1.0115; Basic minor diameter (D - 2h) printed 0.9720 vs 0.9550)
Mates
3/4-11.5NHR 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 3/4-11.5NHR EXTevery column of the workbook row
| Designation | 3/4-11.5NHR EXT |
|---|---|
| Decimal / alternate designation | 0.7500-11.5NHR EXT |
| Threads per inch | 11.5 |
| Thread form | NHR |
| 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.) | 1.0680 |
| Size category | Standard sizes (Tables 1-8) |
| Source table | Table 2 |
| Printed page | 5 |
| Major dia max (in.) | 1.0520 |
| Major dia min (in.) | 1.0350 |
| Major dia tolerance (in.) | 0.0170 |
| Allowance es (in.) | 0.0160 |
| Basic pitch dia D2 (in.) | 1.0160 |
| Pitch dia max (in.) | 0.0100 |
| Pitch dia min (in.) | 0.9930 |
| PD tolerance (in.) | 0.0170 |
| Basic minor dia D1 (in.) | 0.9720 |
| Minor dia max (in.) | 0.9495 |
| Minor dia min (in.) | not given in the standard |
| Minor dia tolerance (in.) | not given in the standard |
| Major dia status | Toleranced (Table 2; NHR excluded from para. 3.1) |
| Minor dia status | Maximum printed (Table 2); minimum not given in the standard (NHR) |
| Root radius max (in.) | not given in the standard |
| Root radius min (in.) | not given in the standard |
| Lead variation ± (in.) (Table 5) | 0.0049 |
| Half-angle variation ± (Table 5) | 3° 44′ |
| Lead variation from PD tol (calc) (in.) | 0.0049 |
| Half-angle variation from PD tol (calc) | 3° 44′ |
| 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.) | 1.052000 |
| Sweep cut: tip diameter (in.) | 0.949500 |
| Sweep cut: depth (in.) | 0.051250 |
| Sweep cut: profile width at start diameter (in.) | 0.070048 |
| Crest flat as modelled (in.) | 0.016909 |
| Taper | none (straight thread) |
| Service | Garden hose formed thread |
| Mating group (compatible designations) | GH-3/4-11.5 |
| Mating member of the same designation | 3/4-11.5NHR INT |
| Other designations in the mating group | 3/4-11.5NH |
| Min PD clearance: coupling min PD - nipple max PD (in.) | 1.0060 |
| Max PD clearance: coupling max PD - nipple min PD (in.) | 0.0350 |
| Min major dia clearance: coupling min - nipple max (in.) | 0.0160 |
| Min minor dia clearance: coupling min - nipple max (in.) | 0.0225 |
| 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.) | 1.0100 |
| Table 6 ring gage: GO pitch min (in.) | 1.0097 |
| Table 6 ring gage: GO minor max (in.) | 0.9720 |
| Table 6 ring gage: GO minor min (in.) | 0.9726 |
| Table 6 ring gage: NOT GO pitch max (in.) | 0.9933 |
| Table 6 ring gage: NOT GO pitch min (in.) | 0.9930 |
| Table 6 ring gage: NOT GO minor max (in.) | 0.9748 |
| Table 6 ring gage: NOT GO minor min (in.) | 0.9742 |
| Table 6 ring gage: Z GO major max (in.) | 1.05200 |
| Table 6 ring gage: Z GO major min (in.) | 1.05188 |
| Table 6 ring gage: Z NOT GO major max (in.) | 1.03512 |
| Table 6 ring gage: Z NOT GO major min (in.) | 1.03500 |
| Table 8 setting plug: GO truncated major max (in.) | 1.0387 |
| Table 8 setting plug: GO truncated major min (in.) | 1.0381 |
| Table 8 setting plug: GO full major max (in.) | 1.0526 |
| Table 8 setting plug: GO full major min (in.) | 1.0520 |
| Table 8 setting plug: GO pitch max (in.) | 1.0100 |
| Table 8 setting plug: GO pitch min (in.) | 1.0097 |
| Table 8 setting plug: NOT GO truncated major max (in.) | 1.0307 |
| Table 8 setting plug: NOT GO truncated major min (in.) | 1.0301 |
| Table 8 setting plug: NOT GO full major max (in.) | 1.0526 |
| Table 8 setting plug: NOT GO full major min (in.) | 1.0520 |
| Table 8 setting plug: NOT GO pitch max (in.) | 0.9933 |
| Table 8 setting plug: NOT GO pitch min (in.) | 0.9930 |
| Table 8 setting plug: Full-form GO major max (in.) | 1.0526 |
| Table 8 setting plug: Full-form GO major min (in.) | 1.0520 |
| Table 8 setting plug: Full-form NOT GO major max (in.) | 1.0526 |
| Table 8 setting plug: Full-form NOT GO major min (in.) | 1.0520 |
| Check against formulas | Allowance (coupling min PD - nipple max PD): printed 0.0160, formula 0.0060 | PD tolerance = max - min: printed 0.0170, formula -0.9830 | Table 1 col 7 (p. 4), 3/4-11.5NHR: printed allowance 0.0160; expected 0.0060 (coupling PD min 1.0160 - nipple PD max 1.0100) | Table 2 col 10 (p. 5), 3/4-11.5NHR: printed nipple pitch dia max 0.0100; expected 1.0100 (Table 1 col 9 and Table 6 col 5 print 1.0100) | Table 6 col 6 (p. 9), 3/4-11.5NHR: printed GO minor-dia ring gage max 0.9720 / min 0.9726; expected min 0.9714 (min must be below max for a minus tolerance) | NHR is excluded from paras. 3.1 and 3.2, so its basic/limit values are the table values and differ from D - h, D - 2h by definition (Basic pitch diameter (D - h) printed 1.0160 vs 1.0115; Basic minor diameter (D - 2h) printed 0.9720 vs 0.9550) |
| Notes | Printed value kept. Misprint: Table 1 col 7 (p. 4), 3/4-11.5NHR, printed allowance 0.0160; expected 0.0060 (coupling PD min 1.0160 - nipple PD max 1.0100). Printed value kept. Misprint: Table 2 col 10 (p. 5), 3/4-11.5NHR, printed nipple pitch dia max 0.0100; expected 1.0100 (Table 1 col 9 and Table 6 col 5 print 1.0100). Printed value kept. Misprint: Table 6 col 6 (p. 9), 3/4-11.5NHR, printed GO minor-dia ring gage max 0.9720 / min 0.9726; expected min 0.9714 (min must be below max for a minus tolerance). NHR (formed thread) is excluded from paras. 3.1 and 3.2: tolerances and minimum/maximum values are the printed table values. 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.