DN to INCHI

NPS - 'Nominal Pipe Size' and DN - 'Diametre Nominal' The size of pipes, fittings, flanges and valves are often given in inches as NPS - Nominal Pipe Size, or in metric units as DN - 'Diametre Nominal' Pipe is made of a wide variety of materials - like galvanized steel, black steel, copper, cast iron, concrete, and various plastics such as ABS, PVC, CPVC, polyethylene, polybutylene and more. Pipes are identified by "nominal" or "trade" names that are loosely related to the actual dimensions. For instance, a 2-inch galvanized steel pipe has an inside diameter of about 2 1/8 inches and an outside diameter of about 2 5/8 inches. In plumbing pipe size is referred to as nominal pipe size - NPS, or "Nominal Pipe Size". The metric equivalent is called DN or "diametre nominel". The metric designations conform to International Standards Organization (ISO) usage and apply to all plumbing, natural gas, heating oil, and miscellaneous piping used in buildings. The use of NPS does not conform to American Standard pipe designations where the term NPS means "National Pipe Thread Straight". Diameter Nominal DN (mm)

Nominal Pipe Size NPS (inches)

Diameter Nominal DN (mm) 700

Nominal Pipe Size NPS (inches) 28

6

1/8

8

1/4

750

30

10

3/8

800

32

15

1/2

900

36

20

3/4

1000

40

25

1

1050

42

32

1 1/4

1100

44

40

1 1/2

1200

48

50

2

1300

52

65

2 1/2

1400

56

80

3

1500

60

100

4

1600

64

150

6

1700

68

200

8

1800

72

250

10

1900

76

300

12

2000

80

350

14

2200

88

400

16

Diameter Nominal DN (mm)

Nominal Pipe Size NPS (inches)

450

18

500

20

550

22

600

24 26

650

Diameter Nominal DN (mm)

Nominal Pipe Size NPS (inches)