b11 tolerance (shaft, IT11)

Shaft tolerance class b11 per ISO 286-1:2010: fundamental deviation es −140 … −840, grade IT11 (60 µm at ≤ 3 mm to 400 µm at 400–500 mm). For an exact size, open the calculator with b11 selected.

Type
Shaft
Grade
IT11
Tolerance
60 … 400 µm
Fund. deviation
es −140 … −840 µm

b11 limits by size range

Size (mm)Upper (µm)Lower (µm)Ø max (mm)Ø min (mm)
≤ 3−140−2002.8602.800
3 – 6−140−2155.8605.785
6 – 10−150−2409.8509.760
10 – 14−150−26013.85013.740
14 – 18−150−26017.85017.740
18 – 24−160−29023.84023.710
24 – 30−160−29029.84029.710
30 – 40−170−33039.83039.670
40 – 50−180−34049.82049.660
50 – 65−190−38064.81064.620
65 – 80−200−39079.80079.610
80 – 100−220−44099.78099.560
100 – 120−240−460119.760119.540
120 – 140−260−510139.740139.490
140 – 160−280−530159.720159.470
160 – 180−310−560179.690179.440
180 – 200−340−630199.660199.370
200 – 225−380−670224.620224.330
225 – 250−420−710249.580249.290
250 – 280−480−800279.520279.200
280 – 315−540−860314.460314.140
315 – 355−600−960354.400354.040
355 – 400−680−1040399.320398.960
400 – 450−760−1160449.240448.840
450 – 500−840−1240499.160498.760

Deviations at the upper end of each range (Ø columns use that size); use the calculator for the exact size. — : not defined by ISO 286 for that size. Upper/Lower (mm) and inch columns are shown on wider screens.

About b11

b11 denotes a shaft tolerance zone with large clearance deviation in the ISO 286 system.

At Ø25 mm b11 is −0.160 / −0.290 mm, i.e. 24.710 to 24.840 mm.

How the limits are calculated

b11 uses grade IT11 (a standard tolerance of 130 µm at 18–30 mm). Fundamental deviation: es is tabulated directly by ISO 286-1 Table 2; ei = es − IT11. See the fundamental deviation table for every letter. Values per ISO 286-1:2010.

Related classes

B11