Dimensional Tolerances (ASME)
ASME B16.9, B16.28
Pipe Size All Fittings 90 & 45 Elbows and Tees Reducers and Lap Joint Stub ends Caps
Outside Diameter at Bevel, D (1) Inside Diameter at End (1) Wall                Thickness        t  Center-to-End Dimensions  A,B,C,M Overall Length,                    F,H
Overall Length, E
IN MM IN MM   IN MM IN MM IN MM
½ ~ 2½ +0.06 +1.6 ±0.03 ±0.8 Not Less Than 87.5% of Nominal Thickness ±0.06 ±2 ±0.06 ±2 ±0.12 ±3
-0.03 -0.8
3 ~ 2½ ±0.06 ±1.6 ±0.06 ±1.6
4
5 ~ 8 +0.09 +2.4 ±0.25 ±6
-0.06 -1.6
10 ~ 18 +0.16 +4.0 ±0.12 ±3.2 ±0.09 ±0.09
-0.12 -3.2
20 ~ 24 +0.25    -0.19 +6.4         -4.8 ±0.19 ±4.8
26 ~ 30 ±0.12 ±3 ±0.19 ±5 ±0.38 ±10
32 ~ 48 ±0.19 ±5
Pipe Size Lap Joint Stub Ends (2) 180 Return Bends
Outside Diameter of Lap, G Lap Thickness Fillet Radius of Lap, R Center-to-Center Dimension, O Back-to- Face Dimension, K Alignment of Ends, U
IN MM IN MM IN MM IN MM IN MM IN MM
½ ~ 2½ +0           -0.03 +0                -1 +0.06                -0 +1.6                -0 +0           -0.03 +0                -1 ±0.25 ±6 ±0.25 ±6 ±0.03 ±1
3 ~ 2½
4 +0            -0.06 +0                -2
5 ~ 8
10 ~ 18 +0            -0.06 +0                -2 +0.12                -0 +3.2                -0 ±0.38 ±10 ±0.06 ±2
20 ~ 24
Pipe Size Off Angle, Q Off Plane, P
IN MM IN MM
½ ~ 4 ± 0.03 ± 1 ± 0.06 ± 2
5 ~ 8 ± 0.06 ± 2 ± 0.12 ± 4 NOTES: 
10 ~ 12 ± 0.09 ± 0.19 ± 5 (1) Out-of-round is the sum of absolute
14 ~ 16 ± 3 ± 0.25 ± 6 values of plus and minus tolerances.
18 ~ 24 ± 0.12 ± 4 ± 0.38 ± 10 (2) Outside diameter of barrel see the table 
26 ~ 30 ± 0.19 ± 5 on page 15.
32 ~ 42 ± 0.50 ± 13
44 ~ 48 ± 0.75 ± 19