Machine Drawing

210 Machine Drawing

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d:\N-Design\Des15-1.pm5

Fig. 15.2

Degree of accuracy expected of manufacturing process

16 15 14 13 12 11 10 9 8 7 6 5 4 3 2 1

25

50

75

100

2500 1250 500 250

50 25 5 0

m Tolerance, m

Diameters (mm)

Tolerance

grades

16 Sand casting (approximately);

flame cutting

15 Stamping (approximately)14 Die casting or moulding; rubber

moulding

13 Press work; tube rolling12 Light press work; tube drawing11 Drilling, rough turning and boring;

precision tube drawing

10 Milling, slotting, planing, metal

rolling or extrusion

9

Worn capstan or automatic,horizontal, or vertical boringmachine

8

Centre lathe turning and boring,reaming, capstan or automatic ingood condition

7

High quality turning, broaching,honing

6

Grinding, fine honing

5

Ball bearings, machine lapping,diamond or fine boring, finegrinding

4

Gauges, fits of extreme precision,produced by lapping

3

Good quality gauges, gap gauges

2

High quality gauges, plug gauges

1

Slip blocks, reference gauges