Spot facing

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منظور محل قرارگیری Head پیچ است

2.1 U.S. Customary (Inch-Series) Bolting 

2.1.1 The dimensions for spot facing apply  to the use of hexagon head bolts or hexagon  nuts in accordance with ASME B18.2.1 and  ASME B18.2.2 (heavy series). For bolt sizes 1/2 and 5/8, the minimum diameter of spot facing is sufficient for regular square head  bolts, in accordance with ASME B18.2.1.

2.1.2 The minimum spot facing diameters  illustrated in Figure 1, are listed in Table 1  for bolt sizes 1/2 inch through 31⁄2 inches.

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