11" × 3 TPI BUTT (pull type) External Thread Specifications

11-3 BUTT-2A · 11.0000-3 BUTT-2A

ASMESTD: ASME B1.9SOURCE: Table 3, Tables 1, 2, 5TYPE: External (bolt/screw)CLASS: 2AFLANKS 7° / 45°ROOT: roundTable 1 combination

Thread profile

11-3 BUTT-2A: solid = maximum material, dotted = minimum material, dashed = basic profile before the allowance. Flanks 7° (pressure) and 45° (clearance) from the radial line, 52° thread angle; drawn to scale.

Limits of size, class 2A

Dimension	Basic	Max	Min	Tolerance
Major diameter dCrest of the male thread, max = D − G	11.0000	10.9902	10.9755	0.0147
Pitch diameter EMax = D − h − G	10.8000	10.7902	10.7755	0.0147
Minor diameter KsRoot of the male thread; min is a reference value	10.6000	10.5484	10.5062ref.	0.0422ref.
Allowance GSpace below basic size; equals the Class 3 PD tolerance (Sec. 7)		0.0098
Root radius rRound root, male (Fig. 1a)		0.023803	0.011900
Thread engagement heh − G/2 at max, less the PD tolerance at min		0.195100	0.180400

Dimensions in inches. Values are those of the standard (ASME B1.9); 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 female thread, limits of size, class 2B

Dimension	Basic	Max	Min	Tolerance
Major diameter DnRoot of the female thread, min = D + 0.12542p; max for reference	11.0000	11.0840ref.	11.0418
Pitch diameter EMin = D − h	10.8000	10.8147	10.8000	0.0147
Minor diameter KnCrest of the female thread, min = D − 2h	10.6000	10.6147	10.6000	0.0147
Root radius rRound root, female (Fig. 1a)		0.023803	0.011900

Lead, flank angle and length of engagement

Lead + flank variation limit Σ: 0.01470 inPitch diameter equivalent of lead and flank errors together (Class 2: the PD tolerance; Class 3: half)
Lead variation alone ±δl: 0.00825 inAllowable lead error if there is no flank error
45° flank angle variation alone ±δα: 2.321 °Half-angle error of the clearance flank
7° flank angle variation alone ±δα: 4.900 °Half-angle error of the pressure flank

Gaging Sections 10, 11 · Tables 6, 7, 8, 11

Male thread 11-3 BUTT-2A

Gage pitch tolerance (W): 0.00040 in
Gage 7° flank angle tolerance: 5 min
Gage 45° flank angle tolerance: 4 min
Gage major / minor tolerance: 0.0020 in
Gage pitch diameter tolerance: 0.00050 in
PD equivalent of pitch and flank tolerance: 0.0014 in
GO pitch diameter limit: 10.7902 in
NOT GO pitch diameter limit: 10.7755 in
NOT GO truncated crest diameter: 10.6588 in
Setting plug truncated major diameter: 10.9235 in
Best-size wire: 0.18049 · C = 0.27288 in, C
Maximum wire: 0.20478 · C = 0.34959 in, C

Female thread 11-3 BUTT-2B

Gage pitch tolerance (X): 0.00060 in
Gage flank angle tolerance: 5 min
Gage major / minor tolerance: 0.0020 in
Gage pitch diameter tolerance: 0.00100 in
PD equivalent of pitch and flank tolerance: 0.0019 in
GO pitch diameter limit: 10.8000 in
NOT GO pitch diameter limit: 10.8147 in
NOT GO truncated crest diameter: 10.9314 in
Plain gage tolerance: 0.00040 in
Root relief width GO: 0.055667 in
Root relief width NOT GO: 0.083333 in

Notes

Class 2: no taper/roundness requirement (para. 6.6.1).

Mates

11-3 BUTT-2A screws into a thread of the same standard at the same size and pitch. The standard mating internal thread is class 2B. 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

→ 11" × 1.25 TPI → 11" × 1.5 TPI → 11" × 10 TPI → 11" × 2.5 TPI → 11" × 2 TPI → 11" × 4 TPI → 11" × 5 TPI → 11" × 6 TPI → 11" × 8 TPI → 10" × 8 TPI → 12" × 1.25 TPI → 11" × 3 TPI internal

All values for 11-3 BUTT-2Aevery column of the workbook row

All values of the workbook row 11-3 BUTT-2A
Designation	11-3 BUTT-2A
Decimal designation	11.0000-3 BUTT-2A
Threads per inch	3
Thread form	BUTT
Series (Table 1)	BUTT
Series name	Pull type, rounded root (default)
External / internal	External
Class	2A
Nominal size (in.)	11
Pitch P (in.)	0.33333333
Basic major dia D (in.)	11.0000
Size category	Table 1 combination
Source table	Table 3, Tables 1, 2, 5
Printed page	4, 5, 6, 10
Major dia max (in.)	10.9902
Major dia min (in.)	10.9755
Major dia tolerance (in.)	0.0147
Major dia status	Toleranced: D - G (max), minus the PD tolerance (min) (paras. 6.2, 7)
Allowance G (in.; internal: mating external value, reference)	0.0098
Tolerance range (Tables 3-5)	Over 10 thru 16
Range over (in.)	10.0
Range thru (in.)	16.0
Range mean dia for formula (in.)	13.000
Length of engagement Le = 10P (in.)	3.3333
Basic pitch dia E = D - h (in.)	10.8000
Pitch dia max (in.)	10.7902
Pitch dia min (in.)	10.7755
PD tolerance (in.)	0.0147
Basic minor dia K = D - 2h (in.)	10.6000
Minor dia max (in.)	10.5484
Minor dia min (in.)	10.5062
Minor dia tolerance (in.)	0.0422
Minor dia status	Max = D - 1.32542P - G; min is reference only = min PD - 0.80803P (para. 6.3, Sec. 4)
Root radius max (in.)	0.023803
Root radius min (in.)	0.011900
Root truncation s max (in.)	0.027533
Root truncation s min (in.)	0.013767
Engagement height he max (in.)	0.195100
Engagement height he min (in.)	0.180400
Lead + flank PD-equivalent limit (in.)	0.01470
Lead variation alone ± (in.)	0.00825
45° flank variation alone ± (deg)	2.321
7° flank variation alone ± (deg)	4.900
Lead angle at basic PD (deg)	0.5629
Lead angle (deg min)	0° 34′
Tensile stress area As (sq in.)	not given in the standard
Thread angle (deg)	52
Pressure (load) flank angle (deg)	7
Clearance flank angle (deg)	45
Flank orientation	Pull type (external thread pulls): 45° clearance flank leads, 7° load flank follows (Sec. 9)
Sharp V height H (in.)	0.296880
Basic thread engagement height h (in.)	0.200000
Thread height hs = hn (in.)	0.220903
Crest truncation f (in.)	0.048440
Crest width F (in.)	0.054387
Sweep cut: start diameter (in.)	10.990200
Sweep cut: tip diameter (in.)	10.548400
Sweep cut: depth (in.)	0.220903
Sweep cut: profile width at start diameter (in.)	0.278947
Sweep cut: tip width (root flat S max or radius r max) (in.)	0.023803
Constant c = 0.80803P (in.)	0.269343
PD tolerance component 0.00854√P (in.)	0.004931
W gage: pitch tolerance (in.)	0.00040
W gage: 7° flank tolerance (min)	5
W gage: 45° flank tolerance (min)	4
W gage: major/minor tolerance (in.)	0.0020
W gage: PD tolerance (in.)	0.00050
W gage: PD equivalent of pitch/flank tol. (in.)	0.0014
Z plain gage tolerance (in.)	0.00040
GO gage PD limit (in.)	10.7902
NOT GO gage PD limit (in.)	10.7755
NOT GO crest/minor truncated dia (in.)	10.6588
Setting plug truncated major dia (in.)	10.9235
Root relief width GO (0.167P) (in.)	0.055667
Root relief width NOT GO (0.25P) (in.)	0.083333
Best-size wire (in.)	0.18049
Measurement constant C, best wire (in.)	0.27288
Maximum wire (in.)	0.20478
Measurement constant C, max wire (in.)	0.34959
Check against formulas	OK
Notes	Class 2: no taper/roundness requirement (para. 6.6.1).

ASME B1.9: Buttress Inch Screw Threads. Source: workbook data (2026-10-10). Confirm against your licensed copy of the standard before use.