Bảng tra kích thước ren hệ inch - tiêu chuẩn NPT

Nominal Diameter

Major Diameter
mm

Tapping
Drill Size
mm

TPI

Pitch
mm

1/16" - 27 NPT

7.895

6.00

27

0.941

1/8" - 27 NPT

10.242

8.25

27

0.941

1/4" - 18 NPT

13.616

10.70

18

1.411

3/8" - 18 NPT

17.055

14.10

18

1.411

1/2" - 14 NPT

21.223

17.40

14

1.814

3/4" - 14 NPT

26.568

22.60

14

1.814

1" - 11 1/2 NPT

33.228

28.50

11.5

2.209

1 1/4" - 11 1/2 NPT

41.985

37.00

11.5

2.209

1 1/2" - 11 1/2 NPT

48.054

43.50

11.5

2.209

2" - 11 1/2 NPT

60.092

55.00

11.5

2.209

2 1/2" - 8 NPT

72.699

65.50

8

3.175

3" - 8 NPT

88.608

81.50

8

3.175

3 1/2" - 8 NPT

101.316

94.30

8

3.175

4" - 8 NPT

113.973

107.00

8

3.175

5" - 8 NPT

141.300

134.384

8

3.175

6" - 8 NPT

168.275

161.191

8

3.175

8" - 8 NPT

219.075

211.673

8

3.175

10" - 8 NPT

273.050

265.311

8

3.175

12" - 8 NPT

323.850

315.793

8

3.175