• Facebook
  • ins
  • twitter
  • youtube
  • instagram-fill

Stainless Steel Tube & Pipe Sizes: NPS, Pipe Schedule, DN

There are several common methods for describing pipe and tube dimension used in tubular piping system, we should calculate exact sizes without confusion, usually tube and pipe sizes is defined by outside diameter, wall thickness and length, inside diameter is also mentioned for tube sizes, these parameters are basic to dimensions concept.

news-3 (1)

Nominal Pipe Size

The North American ANSI system is widely applied in pipe system, Nominal Pipe Size (NPS) is defined standard sizes for pipes used for different pressures and temperatures, the outside diameter is used in inches, NPS and OD values are not always equal, from NPS ⅛ to 12 inch, the NPS and OD values are different, over 14 inch, the NPS and OD values are equal, the size is actual dimensions, not nominal.

NB

NB (Nominal Bore) is also another method to refer pipe sizes and dimensions, it is the same value between NB and NPS.

Pipe Schedule

Wall thickness referred to as the Schedule (Sch.), nowadays, there are large selection of wall thicknesses to meet all applications under different pressure, standard weight (STD), extra-strong (XS), and double extra-strong (XXS) is three main number for thickness, 5S and 10S are thinner wall thickness for stainless steel pipe.

DN Size

The European ISO system is also OD based, Diameter Nominal (DN) is also frequently referred to pipe dimensions, it provides almost the same OD as the ANSI system, but measured in millimeters, and with a lot more choices for different wall thickness.

Nominal Pipe Size, Diameter Nominal And Pipe Schedule Chart

ASME B36.19 indicates Stainless Steel Pipe dimensions including the outside diameter and the Schedule wall thickness, the Schedule Number has an “S” suffix for wall thickness, having SCH 5S, SCH 10S, SCH 40S, SCH 80S.
ASME B36.10 standard determines carbon steel pipe dimensions, without an “S” suffix for pipe schedule.

Nominal Size

OD

Wall Thickness, SCH

NPS

DN

Mm

5S

10S

10

20

30

40S

STh

40

60

80S

XS

80

100

120

140

160

XXS

1∕8

6

10.3

1.24

1.73

1.73

1.73

2.41

2.41

2.41

1∕4

8

13.7

1.65

2.24

2.24

2.24

3.02

3.02

3.02

3∕8

10

17.2

1.65

2.31

2.31

2.31

3.2

3.2

3.2

1∕2

15

21.3

1.65

2.11

2.77

2.77

2.77

3.73

3.73

3.73

4.78

7.47

3∕4

20

26.7

1.65

2.11

2.87

2.87

2.87

3.91

3.91

3.91

5.56

7.82

1

25

33.4

1.65

2.77

3.38

3.38

3.38

4.55

4.55

4.55

6.35

9.09

1 1∕4

32

42.2

1.65

2.77

3.56

3.56

3.56

4.85

4.85

4.85

6.35

9.7

1 1∕2

40

48.3

1.65

2.77

3.68

3.68

3.68

5.08

5.08

5.08

7.14

10.15

2

50

60.3

1.65

2.77

3.91

3.91

3.91

5.54

5.54

5.54

8.74

11.07

2 1∕2

65

73

2.11

3.05

5.16

5.16

5.16

7.01

7.01

7.01

9.53

14.02

3

80

88.9

2.11

3.05

5.49

5.49

5.49

7.62

7.62

7.62

11.13

15.24

3 1∕2

90

101.6

2.11

3.05

5.74

5.74

5.74

8.08

8.08

8.08

4

100

114.3

2.11

3.05

6.02

6.02

6.02

8.56

8.56

8.56

11.13

13.49

17.12

5

125

141.3

2.77

3.4

– –

6.55

6.55

6.55

9.53

9.53

9.53

12.7

15.88

19.05

6

150

168.3

2.77

3.4

7.11

7.11

7.11

10.97

10.97

10.97

14.27

18.26

21.95

8

200

219.1

2.77

3.76

6.35

7.04

8.18

8.18

8.18

10.31

12.7

12.7

12.7

15.09

18.26

20.62

23.01

22.23

10

250

273.1

3.4

4.19

6.35

7.8

9.27

9.27

9.27

12.7

12.7

12.7

15.09

18.26

21.44

25.4

28.58

25.4

12

300

323.9

3.96

4.57

6.35

8.38

9.53

9.53

10.31

14.27

12.7

12.7

17.48

21.44

25.4

28.58

33.32

25.4

14

350

355.6

3.96

4.78

6.35

7.92

9.53

9.53

11.13

15.09

12.7

19.05

23.83

27.79

31.75

35.71

16

400

406.4

4.19

4.78

6.35

7.92

9.53

9.53

12.7

16.66

12.7

21.44

26.19

30.96

36.53

40.49

18

450

457.2

4.19

4.78

6.35

7.92

11.13

9.53

14.27

19.05

12.7

23.83

29.36

34.93

39.67

45.24

20

500

508

4.78

5.54

6.35

9.53

12.7

9.53

15.09

20.62

12.7

26.19

32.54

38.1

44.45

50.01

22

550

558.8

4.78

5.54

6.35

9.53

12.7

9.53

22.23

12.7

28.58

34.93

41.28

47.63

53.98

24

600

609.6

5.54

6.35

6.35

9.53

14.27

9.53

17.48

24.61

12.7

30.96

38.89

46.02

52.37

59.54

26

650

660.4

7.92

12.7

9.53

12.7

28

700

711.2

7.92

12.7

15.88

9.53

12.7

30

750

762

6.35

7.92

7.92

12.7

15.88

9.53

12.7

32

800

812.8

7.92

12.7

15.88

17.48

9.53

17.48

12.7

34

850

863.6

7.92

12.7

15.88

17.48

9.53

17.48

12.7

36

900

914.4

7.92

12.7

15.88

19.05

9.53

19.05

12.7

38

950

965.2

9.53

12.7

40

1000

1016

9.53

Nominal Size

OD

Wall Thickness, SCH

NPS

DN

Mm

5S

10S

10

20

30

40S

STh

40

60

80S

XS

80

100

120

140

160

XXS

1∕8

6

10.3

1.24

1.73

1.73

1.73

2.41

2.41

2.41

1∕4

8

13.7

1.65

2.24

2.24

2.24

3.02

3.02

3.02

3∕8

10

17.2

1.65

2.31

2.31

2.31

3.2

3.2

3.2

1∕2

15

21.3

1.65

2.11

2.77

2.77

2.77

3.73

3.73

3.73

4.78

7.47

3∕4

20

26.7

1.65

2.11

2.87

2.87

2.87

3.91

3.91

3.91

5.56

7.82

1

25

33.4

1.65

2.77

3.38

3.38

3.38

4.55

4.55

4.55

6.35

9.09

1 1∕4

32

42.2

1.65

2.77

3.56

3.56

3.56

4.85

4.85

4.85

6.35

9.7

1 1∕2

40

48.3

1.65

2.77

3.68

3.68

3.68

5.08

5.08

5.08

7.14

10.15

2

50

60.3

1.65

2.77

3.91

3.91

3.91

5.54

5.54

5.54

8.74

11.07

2 1∕2

65

73

2.11

3.05

5.16

5.16

5.16

7.01

7.01

7.01

9.53

14.02

3

80

88.9

2.11

3.05

5.49

5.49

5.49

7.62

7.62

7.62

11.13

15.24

3 1∕2

90

101.6

2.11

3.05

5.74

5.74

5.74

8.08

8.08

8.08

4

100

114.3

2.11

3.05

6.02

6.02

6.02

8.56

8.56

8.56

11.13

13.49

17.12

5

125

141.3

2.77

3.4

– –

6.55

6.55

6.55

9.53

9.53

9.53

12.7

15.88

19.05

6

150

168.3

2.77

3.4

7.11

7.11

7.11

10.97

10.97

10.97

14.27

18.26

21.95

8

200

219.1

2.77

3.76

6.35

7.04

8.18

8.18

8.18

10.31

12.7

12.7

12.7

15.09

18.26

20.62

23.01

22.23

10

250

273.1

3.4

4.19

6.35

7.8

9.27

9.27

9.27

12.7

12.7

12.7

15.09

18.26

21.44

25.4

28.58

25.4

12

300

323.9

3.96

4.57

6.35

8.38

9.53

9.53

10.31

14.27

12.7

12.7

17.48

21.44

25.4

28.58

33.32

25.4

14

350

355.6

3.96

4.78

6.35

7.92

9.53

9.53

11.13

15.09

12.7

19.05

23.83

27.79

31.75

35.71

16

400

406.4

4.19

4.78

6.35

7.92

9.53

9.53

12.7

16.66

12.7

21.44

26.19

30.96

36.53

40.49

18

450

457.2

4.19

4.78

6.35

7.92

11.13

9.53

14.27

19.05

12.7

23.83

29.36

34.93

39.67

45.24

20

500

508

4.78

5.54

6.35

9.53

12.7

9.53

15.09

20.62

12.7

26.19

32.54

38.1

44.45

50.01

22

550

558.8

4.78

5.54

6.35

9.53

12.7

9.53

22.23

12.7

28.58

34.93

41.28

47.63

53.98

24

600

609.6

5.54

6.35

6.35

9.53

14.27

9.53

17.48

24.61

12.7

30.96

38.89

46.02

52.37

59.54

26

650

660.4

7.92

12.7

9.53

12.7

28

700

711.2

7.92

12.7

15.88

9.53

12.7

30

750

762

6.35

7.92

7.92

12.7

15.88

9.53

12.7

32

800

812.8

7.92

12.7

15.88

17.48

9.53

17.48

12.7

34

850

863.6

7.92

12.7

15.88

17.48

9.53

17.48

12.7

36

900

914.4

7.92

12.7

15.88

19.05

9.53

19.05

12.7

38

950

965.2

9.53

12.7

40

1000

1016

9.53

SUMMARY: from above table, we can see that:

▪ NPS and DN value are different, they have a corresponding value for outside diameter in millimeter, when NPS ≥ 4, the related DN = 25 multiplied by the NPS number.
▪ From NPS 1/8 to NPS 12 (including) the value is nominal, not actual OD, for example, NPS 6 inch (DN150), pipe outside diameter should be 168.3 mm, not 152.4 mm.
▪ When NPS over and including 14, pipe OD should actual dimension, for example, NPS20 inch, the diameter should be 508 mm, it convert inch to mm by multiplying it with 25.4.
▪ Pipe inside diameter is defined by outside diameter and Schedule.

Examples Of actual outside diameter

▪ NPS 1 actual O.D. = 1.5/16″ (33.4 mm)
▪ NPS 2 actual O.D. = 2.3/8″ (60.3 mm)
▪ NPS 3 actual O.D. = 3.1/2″ (88.9 mm)
▪ NPS 4 actual O.D. = 4.1/2″ (114.3 mm)
▪ NPS 12 actual O.D. = 12.3/4″ (323.9 mm)
▪ NPS 14 ACTUAL O.D. = 14″(355.6 MM, 14 x 25.4 mm)

Difference Between Pipe And Tube Dimension

In general, NPS is a pipe sizes number which refers to a nominal diamter, not actual diamter as specified above, the actual physical OD is larger than it’s nominal OD, and schedule number is for pipe thickness mentioned, pipe can be measured by inside diameter, because pipe is used to transportation fluid, it needs to calculate relevant parameter。
Tube sizes is expressed in inch or millimeter, it is actual value, the actual physical OD of a tube is just the same as it’s nominal OD in both outside diameter and wall thickness, tube dimension in wall thickness is not expressed by Schedule Numble, see more tube size chart.

news-3 (2)

Stainless Steel Tubing Sizes Chart

TUBE O.D (INCH)

TUBE 0.D (MM)

WALL THICKNESS (INCH)

WALL THICKNESS (MM)

BWG

0.188

4.78

0.035

0.89

 20

0.250

6.35

0.020

0.51

0.028

0.71

 22

0.035

0.89

 20

0.049

1.25

 18

0.065

1.65

 16

0.313

7.95

0.035

0.89

 20

0.049

1.25

 18

0.375

9.53

0.028

0.71

 22

0.035

0.89

 20

0.049

1.25

 18

0.065

1.65

 16

0.500

12.7

0.035

0.89

 20

0.049

1.25

 18

0.650

1.65

 16

0.625

15.88

0.035

0.89

 20

0.049

1.25

 18

0.065

1.65

 16

0.750

19.05

0.035

0.89

 20

0.049

1.25

 18

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

0.875

22.23

0.035

0.89

 20

0.049

1.25

 18

0.065

1.65

 16

0.120

3.05

 11

1.000

25.4

0.035

0.89

 20

0.049

1.25

 18

0.065

1.65

 16

0.083

2.11

 14

0.095

2.41

 13

0.120

3.05

 11

1.125

28.58

0.065

1.65

 16

1.250

31.75

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

1.375

34.93

0.035

0.89

 20

1.5000

38.1

0.049

1.25

 18

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

1.750

44.45

0.035

0.89

 20

0.065

1.65

 16

0.083

2.11

 14

1.875

47.63

0.065

1.65

 16

2.000

50.8

0.049

1.25

 18

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

2.125

53.98

0.065

1.65

 16

2.250

57.15

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

2.500

63.5

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

2.750

69.85

0.065

1.65

 16

3.000

76.2

0.049

1.25

 18

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

3.250

82.55

0.065

1.65

 16

0.120

3.05

 11

3.500

88.9

0.065

1.65

 16

4.000

101.6

0.065

1.65

 16

0.083

2.11

 14

4.250

108

0.120

3.05

 11

4.500

114.3

0.065

1.65

 16

5.000

127

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

0.188

4.78

6.000

152.4

0.065

1.65

 16

0.083

2.11

 14

0.120

3.05

 11

8.000

203.2

0.120

3.05

 1

Round Stainless Steel Tube Weight Chart, Per Meter

Wall Thickness Mm

Ø Outside Mm

0,8

1

1,2

1,5

1,6

2,0

2,5

2,6

3

3,2

3,6>

4

5

6

0,104

0,125

8

0,144

0,175

10

0,184

0,225

0,264

0,319

0,337

12

0,224

0,275

0,325

0,394

0,417

13

0,244

0,3

0,355

0,432

14

0,264

0,326

0,385

0,47

0,497

0,601

15

0,284

0,351

0,415

0,507

0,537

0,651

16

0,304

0,376

0,445

0,545

0,577

0,701

17,2

3/8″

0,329

0,406

0,481

0,59

0,625

0,761

0,92

0,951

18

0,345

0,426

0,505

0,62

0,657

0,801

0,97

1,003

19

0,365

0,451

0,535

0,657

0,697

0,851

1,033

1,068

19,05

0,366

0,452

0,536

0,659

0,699

0,854

1,036

1,071

20

0,385

0,476

0,565

0,695

0,737

0,901

1,096

1,133

21,3

1/2″

0,411

0,508

0,604

0,744

0,789

0,967

1,177

1,217

22

0,425

0,526

0,625

0,77

0,817

1,002

1,221

1,263

23

0,445

0,551

0,655

0,808

0,857

1,052

1,283

1,328

25

0,485

0,601

0,715

0,883

0,937

1,152

1,409

1,458

1,653

25,4

0,493

0,611

0,727

0,898

0,954

1,172

1,434

1,484

1,683

26,9

3/4″

0,523

0,649

0,772

0,954

1,014

1,247

1,527

1,582

1,795

28

0,545

0,676

0,805

0,995

1,058

1,302

1,596

1,654

1,878

30

0,585

0,726

0,865

1,07

1,138

1,402

1,722

1,784

2,028

2,147

31,8

0,621

0,771

0,919

1,138

1,21

1,492

1,834

1,901

2,163

2,292

32

0,625

0,776

0,925

1,146

1,218

1,502

1,847

1,914

2,178

2,308

33

0,645

0,801

0,956

1,183

1,258

1,552

1,909

1,979

2,254

2,388

33,7

1″

0,659

0,819

0,977

1,209

1,286

1,588

1,953

2,025

2,306

2,444

34

0,665

0,826

0,986

1,221

1,298

1,603

1,972

2,044

2,329

2,468

35

0,685

0,851

1,016

1,258

1,338

1,653

2,035

2,109

2,404

2,548

38

0,745

0,926

1,106

1,371

1,458

1,803

2,222

2,305

2,629

2,788

38,1

0,747

0,929

1,109

1,375

1,462

1,808

2,229

2,311

2,637

2,796

40

0,785

0,977

1,166

1,446

1,538

1,903

2,348

2,435

2,779

2,949

42

0,825

1,027

1,226

1,521

1,619

2,003

2,473

2,565

2,93

3,109

42,4

1″1/4

0,833

1,037

1,238

1,536

1,635

2,023

2,498

2,591

2,96

3,141

43

0,845

1,052

1,256

1,559

1,659

2,053

2,535

2,63

3,005

3,189

44,5

0,875

1,089

1,301

1,615

1,719

2,128

2,629

2,728

3,117

3,309

45

0,885

1,102

1,316

1,634

1,739

2,153

2,661

2,76

3,155

3,349

48,3

1″ 1/2

0,952

1,184

1,415

1,758

1,871

2,319

2,867

2,975

3,403

3,614

50

0,986

1,227

1,466

1,822

1,939

2,404

2,974

3,086

3,531

3,75

50,8

1,002

1,247

1,49

1,852

1,971

2,444

3,024

3,138

3,591

3,814

51

1,006

1,252

1,496

1,859

1,979

2,454

3,036

3,151

3,606

3,83

52

1,026

1,277

1,526

1,897

2,019

2,504

3,099

3,216

3,681

3,91

53

1,046

1,302

1,556

1,934

2,059

2,554

3,161

3,281

3,756

3,99

54

1,066

1,327

1,587

1,972

2,099

2,604

3,224

3,346

3,831

4,071

56,5

1,116

1,39

1,662

2,066

2,2

2,729

3,38

3,509

4,019

4,271

4,769

57

1,126

1,402

1,677

2,085

2,22

2,574

3,412

3,542

4,056

4,311

4,814

58,2

1,15

1,432

1,713

2,13

2,268

2,814

3,487

3,62

4,147

4,407

4,922

60

1,186

1,477

1,767

2,197

2,34

2,905

3,6

3,737

4,282

4,551

5,084

5,609

60,3

2″

1,192

1,485

1,776

2,209

2,352

2,92

3,618

3,757

4,304

4,575

5,111

5,639

63,5

1,256

1,565

1,872

2,329

2,48

3,08

3,819

3,965

4,545

4,832

5,4

5,96

64

1,266

1,578

1,887

2,348

2,5

3,105

3,85

3,997

4,582

4,872

5,445

6,01

66,6

1,318

1,643

1,965

2,445

2,604

3,235

4,013

4,167

4,778

5,08

5,679

6,27

70

2,067

2,573

2,74

3,405

4,226

4,388

5,033

5,353

5,986

6,611

73

2,157

2,686

2,861

3,556

4,413

4,583

5,258

5,593

6,256

6,911

76,1

2″ 1/2

2,251

2,802

2,985

3,711

4,607

4,785

5,491

5,841

6,535

7,222

80

2,368

2,948

3,141

3,906

4,852

5,039

5,784

6,154

6,887

7,612

83

2,458

3,061

3,261

4,056

5,039

5,234

6,01

6,394

7,157

7,913

84

2,488

3,099

3,301

4,107

5,102

5,299

6,085

6,474

7,248

8,013

85

2,518

3,136

3,341

4,157

5,165

5,365

6,16

6,554

7,338

8,113

88,9

3″

2,635

3,283

3,498

4,352

5,409

5,618

6,453

6,867

7,689

8,504

100

2,969

3,7

3,942

4,908

6,104

6,341

7,287

7,756

8,69

9,615

101,6

3″1/2

3,017

3,76

4,006

4,988

6,204

6,445

7,407

7,885

8,834

9,776

104

3,089

3,85

4,103

5,108

6,354

6,602

7,587

8,077

9,05

10,016

12,395

108

3,209

4

4,263

5,308

6,604

6,862

7,888

8,397

9,411

10,417

12,896

114,3

4″

3,398

4,237

4,515

5,624

6,999

7,272

8,361

8,902

9,979

11,048

13,684

129

4″1/2

4,789

5,104

6,36

7,919

8,229

9,465

10,08

11,304

12,52

15,525

139,7

5″

5,191

5,533

6,896

8,589

8,926

10,269

10,937

12,269

13,592

16,864

154

7,612

9,484

9,857

11,343

12,083

13,558

15,024

18,655

168,3

6″

8,328

10,379

10,788

12,417

13,229

14,847

16,456

20,445

204

10,116

12,614

13,112

15,099

16,09

18,065

20,032

24,915

219,1

8″

10,872

13,559

14,095

16,233

17,3

19,426

21,544

26,805

Heat Exchanger Tube Size Weight per Meter

Outside Diamete

Birmingham Wire Gauge (BWG)

20

18

16

15

14

13

12

11

10

In

Mm

(0.889 Mm)

(1.245 Mm)

(1.651 Mm)

(1.829 Mm)

(2.108 Mm)

(2.413 Mm)

(2.769 Mm)

(3.048 Mm)

(3.403 Mm)

Weight, Kg/M (Average Wall  )

1/4

0.250

6.350

0.12

0.16

0.19

5/16

0.313

7.950

0.15

0.21

0.25

0.28

3/8

0.375

9.525

0.19

0.25

0.31

0.34

0.39

1/2

0.500

12.700

0.25

0.34

0.45

0.49

0.55

0.61

0.68

0.72

5/8

0.625

15.875

0.33

0.45

0.58

0.64

0.71

0.80

0.89

0.97

3/4

0.750

19.050

0.40

0.55

0.72

0.77

0.88

0.98

1.12

1.20

1.31

7/8

0.875

22.225

0.46

0.64

0.83

0.92

1.04

1.18

1.32

1.44

1.58

1

1.000

25.400

0.54

0.74

0.97

1.06

1.21

1.37

1.55

1.68

1.92

1 1/8

1.125

28.575

0.61

0.83

1.10

1.21

1.37

1.56

1.76

1.92

2.11

1 1/4

1.250

31.750

0.68

0.94

1.23

1.35

1.53

1.76

1.96

2.16

2.40

1 3/8

1.375

34.925

0.74

1.03

1.35

1.49

1.70

1.93

2.19

2.40

2.65

1 1/2

1.500

38.100

0.82

1.13

1.49

1.64

1.87

2.17

2.40

2.63

2.92

1 3/4

1.750

44.450

0.97

1.32

1.74

1.92

2.20

2.50

2.84

3.10

3.44

2

2.000

50.800

1.52

1.99

2.20

2.53

2.89

3.27

3.59

3.97

2 1/4

2.250

57.150

1.73

2.26

2.48

2.87

3.26

3.70

4.06

4.51

2 3/8

2.375

60.325

1.81

2.38

2.63

3.02

3.44

3.93

4.30

4.78

2 1/2

2.500

63.500

1.91

2.52

2.78

3.18

3.66

4.14

4.54

5.04

2 7/8

2.875

73.025

2.20

2.90

3.20

3.68

4.20

4.79

5.25

5.83

3

3.000

76.200

2.31

3.04

3.35

3.85

4.39

5.00

5.49

6.10

3 1/2

3.500

88.900

2.69

3.56

3.93

4.51

5.15

5.86

6.44

7.17

4

4.000

101.60

4.11

4.54

5.21

5.95

6.80

7.47

8.30


Post time: Dec-19-2022