Nominal Pipe  Size 

(NPS)

DN

Outside  Diameter at Bevel

Center- to-Center  P

Back-to-Face

K

1

25

33.4

51

41

1-1/4

32

42.2

64

52

1-1/2

404

8.3

76

62

2

50

60.3

102

81

2-1/2

65

73

127

100

3

80

88.9

152

121

3-1/2

90

101.6

178

140

4

100

114.3

203

159

5

125

141.3

254

197

6

150

168.3

305

237

8

200

219.1

406

313

10

250

273

508

391

12

300

323.8

610

467

14

350

355.6

711

533

16

400

406.4

813

610

18

450

457

914

686

20

500

508

1016

762

22

550

559

1118

838

24

600

610

1219

914