ANSI Standard Tolerances ANSI B4.1-1967 (R1987)

630

Table 1. ANSI Standard Tolerances ANSI B4.1-1967 (R1987)

Table 2. Relation of Machining Processes to Tolerance Grades

Nominal Size,Inches Grade

4

5

6

7

8

9

10

11

12

13

Over

To Tolerances in thousandths of an inch a

a All tolerances above heavy line are in accordance with American-British-Canadian (ABC) agree-

ments.

00.120.120.150.250.40.6 1.0 1.6 2.5460.120.240.150.200.30.50.7 1.2 1.8 3.0570.240.400.150.250.40.60.9 1.4 2.2 3.5690.400.710.20.30.40.7 1.0 1.6 2.8 4.07100.71 1.190.250.40.50.8 1.2 2.0 3.5 5.08121.19 1.970.30.40.6 1.0 1.6 2.5 4.0610161.97 3.150.30.50.7 1.2 1.8 3.0 4.5712183.15 4.730.40.60.9 1.4 2.2 3.55914224.737.090.50.7 1.0 1.6 2.5 4.061016257.099.850.60.8 1.2 1.8 2.8 4.5712182.8512.410.60.9 1.2 2.0 3.0 5.0812203012.4115.750.7 1.0 1.4 2.2 3.56914223515.7519.690.8 1.0 1.6 2.5461016254019.6930.090.9 1.2 2.03581220305030.0941.49 1.0 1.6 2.546101625406041.4956.19 1.2 2.0358122030508056.1976.39 1.6 2.546101625406010076.39100.9 2.03581220305080125100.9131.9 2.5461016254060100160131.9

171.9

3581220305080125200171.9200

4

6

10

16

25

40

60

100

160

250

MACHINING OPERATION TOLERANCE GRADES

456710111213

This chart may be used as a general guide to determine the machining processes that will under normal conditions, pro-duce work withen the toler-ance grades indicated.

(See also Relation of Surface Roughness to Tolerances start-ing on page 702.

Lapping & Honing Cylindrical Grinding

Surface Grinding Diamond Turning Diamond Boring Broaching Reaming Turning Boring Milling

Planing & Shaping Drilling