3/4-11.5 NHR NHR (hose coupling, reduced) Internal Thread Specifications

3/4-11.5NHR INT

ASMESTD: ASME B1.20.7SOURCE: Table 3 · p. 6TYPE: Internal (nut/tapped hole)CLASS: StdSERIES: NHR (hose coupling, reduced)
Major diameter
not given in the standard – 1.0680
max – min
Pitch diameter
1.0280 – 1.0160
max – min
Minor diameter
0.9930 – 0.9720
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

DimensionBasicMaxMinTolerance
Major diameter DPara. 3.1: tolerance = 2 × PD tolerance1.0680not given in the standardref.1.0680not given in the standardref.
Pitch diameter D21.01601.02801.01600.0120
Minor diameter D10.97200.99300.97200.0210
Allowance es—

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 EXT
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
0.0035 in
Half-angle variation ± (Table 5) ±δα
2° 38′
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
H 17/32; T 3/8; n 4 1/4
Depth of the coupling H
0.53125 in
Thread length of the coupling T
0.37500 in

Setting plugs (Table 8) and plug gages (Table 7)

Plug gage GO major max / min
1.0686 / 1.0680 in
Plug gage GO pitch max / min
1.0163 / 1.0160 in
Plug gage NOT GO pitch max / min
1.0280 / 1.0277 in

Notes

  • 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. Maximum major diameter, major diameter tolerance (internal) are reference values from para. 3.2; root radius and stress area are not given in the standard.
  • 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 (Minor dia min = D - 2h printed 0.9720 vs 0.9550; Pitch dia min = D - h printed 1.0160 vs 1.0115)

Mates

3/4-11.5NHR INT takes a thread of the same standard at the same size and pitch. The standard mating external 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 INTevery column of the workbook row
All values of the workbook row 3/4-11.5NHR INT
Designation3/4-11.5NHR INT
Decimal / alternate designation0.7500-11.5NHR INT
Threads per inch11.5
Thread formNHR
SeriesGH
Series nameGarden hose
External / internalInternal
ClassStd
Nominal size of hose1/2, 5/8, 3/4
Pitch P (in.)0.08696
Basic major dia D (in.)1.0680
Size categoryStandard sizes (Tables 1-8)
Source tableTable 3
Printed page6
Major dia max (in.)not given in the standard
Major dia min (in.)1.0680
Major dia tolerance (in.)not given in the standard
Basic pitch dia D2 (in.)1.0160
Pitch dia max (in.)1.0280
Pitch dia min (in.)1.0160
PD tolerance (in.)0.0120
Basic minor dia D1 (in.)0.9720
Minor dia max (in.)0.9930
Minor dia min (in.)0.9720
Minor dia tolerance (in.)0.0210
Major dia statusMinimum printed (Table 3); maximum not given in the standard (NHR)
Minor dia statusToleranced (Table 3; NHR excluded from para. 3.2)
Root radius max (in.)not given in the standard
Root radius min (in.)not given in the standard
Lead variation ± (in.) (Table 5)0.0035
Half-angle variation ± (Table 5)2° 38′
Lead variation from PD tol (calc) (in.)0.0035
Half-angle variation from PD tol (calc)2° 38′
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.)0.972000
Sweep cut: tip diameter (in.)1.068000
Sweep cut: depth (in.)0.048000
Sweep cut: profile width at start diameter (in.)0.066295
Crest flat as modelled (in.)0.020662
Tapernone (straight thread)
ServiceGarden hose formed thread
Mating group (compatible designations)GH-3/4-11.5
Mating member of the same designation3/4-11.5NHR EXT
Other designations in the mating group3/4-11.5NH
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 printedH 17/32; T 3/8; n 4 1/4
Table 4: H depth of coupling (in.)0.53125
Table 4: T thread length of coupling (in.)0.37500
Table 4: approx number of threads in T4.25000
Table 7 plug gage: GO major max (in.)1.0686
Table 7 plug gage: GO major min (in.)1.0680
Table 7 plug gage: GO pitch max (in.)1.0163
Table 7 plug gage: GO pitch min (in.)1.0160
Table 7 plug gage: NOT GO major max (in.)1.0657
Table 7 plug gage: NOT GO major min (in.)1.0651
Table 7 plug gage: NOT GO pitch max (in.)1.0280
Table 7 plug gage: NOT GO pitch min (in.)1.0277
Table 7 plug gage: Z GO minor max (in.)0.97212
Table 7 plug gage: Z GO minor min (in.)0.97200
Table 7 plug gage: Z NOT GO minor max (in.)0.99300
Table 7 plug gage: Z NOT GO minor min (in.)0.99288
Check against formulasNHR 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 (Minor dia min = D - 2h printed 0.9720 vs 0.9550; Pitch dia min = D - h printed 1.0160 vs 1.0115)
NotesNHR (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. Maximum major diameter, major diameter tolerance (internal) are reference values from para. 3.2; root radius and stress area are not given in the standard.

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.