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Stainless Tubing Versus Stainless Pipe Guide

Pipe:

The purpose with a pipe is the transport of a fluid like water, oil or similar, and the most import property is the capacity or the inside diameter.


nps dn pipes


Pipe rated to ANSI B 36.10 ASME (both welded and seamless) follow that the inside diameter (ID) of a NPS 2 inches pipe with

  • Schedule 40 is 2.067"
  • Schedule 80 is 1.939"

The IDs are close to 2" and the nominal diameter relates to this inside diameter. Outside diameter (OD) are 2-3/8" for both schedules 40 and 80 (most commonly manufactured schedules in industry)


Since the outside diameter of a single nominal pipe size is kept constant the inside diameter of a pipe will depend on the "schedule" or the thickness of the pipe. The schedule and the actual thickness of a pipe varies with the size of the pipe.


It is common to identify pipes in inches by using 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".


Nominal Bore (NB) may be specified under British standards classifications along with schedule (wall thickness). The tolerances are looser to pipes compared with tubes and they are often less expensive to produce.


Tube

The nominal dimensions of tubes are based on the outside diameter. If we look at Copper Tubes - ASTM B88 the outside diameter of a 2" pipe is 2.125", relatively close to 2".


nps dn tubes


The inside diameter of a tube will depend on the thickness of the tube. The thickness is often specified as a gauge. If we look at Copper Tubes - ASTM B88 the wall thickness of 0.083"of a 2" pipe is gauge 14.


The tolerances are higher with tubes compared to pipes and tubes are often more expensive to produce than pipes.





Nominal wall thickness for seamless and welded steel pipes according ANSI B36.10 are indicated in the table below:


Nominal Pipe Size
(in)
Outside Diameter
(in)
Schedule
10 20 30 STD 40 60 XS 80 100 120 140 160 XXS
Wall Thickness (in)
1/8 0.405 0.068 0.068 0.095 0.095
1/4 0.540 0.088 0.088 0.119 0.119
3/8 0.675 0.091 0.091 0.126 0.126
1/2 0.840 0.109 0.109 0.147 0.147 0.188 0.294
3/4 1.050 0.113 0.113 0.154 0.154 0.219 0.308
1 1.315 0.133 0.133 0.179 0.179 0.250 0.358
1 1/4 1.660 0.140 0.140 0.191 0.191 0.250 0.382
1 1/2 1.900 0.145 0.145 0.200 0.200 0.281 0.400
2 2.375 0.154 0.154 0.218 0.218 0.344 0.436
2 1/2 2.875 0.203 0.203 0.276 0.276 0.375 0.552
3 3.500 0.216 0.216 0.300 0.300 0.438 0.600
3 1/2 4.000 0.226 0.226 0.318 0.318
4 4.500 0.237 0.237 0.337 0.337 0.438 0.531 0.674
5 5.563 0.258 0.258 0.375 0.375 0.500 0.625 0.750
6 6.625 0.280 0.280 0.432 0.432 0.562 0.719 0.864
8 8.625 0.250 0.277 0.322 0.322 0.406 0.500 0.500 0.594 0.719 0.812 0.906 0.875
10 10.750 0.250 0.307 0.365 0.365 0.500 0.500 0.594 0.719 0.844 1.000 1.125 1.000
12 12.750 0.250 0.330 0.375 0.406 0.562 0.500 0.688 0.844 1.000 1.125 1.312 1.000
14 14.000 0.250 0.312 0.375 0.375 0.438 0.594 0.500 0.750 0.938 1.094 1.250 1.406
16 16.000 0.250 0.312 0.375 0.375 0.500 0.656 0.500 0.844 1.031 1.219 1.438 1.594
18 18.000 0.250 0.312 0.438 0.375 0.562 0.750 0.500 0.938 1.156 1.375 1.562 1.781
20 20.000 0.250 0.375 0.500 0.375 0.594 0.812 0.500 1.031 1.280 1.500 1.750 1.968
22 22.000 0.250 0.375 0.500 0.375 0.875 0.500 1.125 1.375 1.625 1.875 2.125
24 24.000 0.250 0.375 0.562 0.375 0.688 0.989 0.500 1.219 1.531 1.812 2.062 2.344
30 30.000 0.312 0.500 0.625 0.375 0.500
32 32.000 0.312 0.500 0.625 0.375 0.688
34 34.000 0.312 0.500 0.625 0.375 0.688
36 36.000 0.312 0.500 0.625 0.375 0.750
42 42.000 0.500 0.625 0.375 0.750
Nominal Pipe Size (in) 1/8
Outside Diameter (in) 0.405
Schedule
Wall Thickness (in)
10
20
30
STD 0.068
40 0.068
60
XS 0.095
80 0.095
100
120
140
160
XXS
Nominal Pipe Size (in) 1/4
Outside Diameter (in) 0.540
Schedule
Wall Thickness (in)
10
20
30
STD 0.088
40 0.088
60
XS 0.119
80 0.119
100
120
140
160
XXS
Nominal Pipe Size (in) 3/8
Outside Diameter (in) 0.675
Schedule
Wall Thickness (in)
10
20
30
STD 0.091
40 0.091
60
XS 0.126
80 0.126
100
120
140
160
XXS
Nominal Pipe Size (in) 1/2
Outside Diameter (in) 0.840
Schedule
Wall Thickness (in)
10
20
30
STD 0.109
40 0.109
60
XS 0.147
80 0.147
100
120
140
160 0.188
XXS 0.294
Nominal Pipe Size (in) 3/4
Outside Diameter (in) 1.050
Schedule
Wall Thickness (in)
10
20
30
STD 0.113
40 0.113
60
XS 0.154
80 0.154
100
120
140
160 0.219
XXS 0.308
Nominal Pipe Size (in) 1
Outside Diameter (in) 1.315
Schedule
Wall Thickness (in)
10
20
30
STD 0.133
40 0.133
60
XS 0.179
80 0.179
100
120
140
160 0.250
XXS 0.358
Nominal Pipe Size (in) 1 1 /4
Outside Diameter (in) 1.660
Schedule
Wall Thickness (in)
10
20
30
STD 0.140
40 0.140
60
XS 0.191
80 0.191
100
120
140
160 0.250
XXS 0.382
Nominal Pipe Size (in) 1 1 /2
Outside Diameter (in) 1.900
Schedule
Wall Thickness (in)
10
20
30
STD 0.145
40 0.145
60
XS 0.200
80 0.200
100
120
140
160 0.281
XXS 0.400
Nominal Pipe Size (in) 2
Outside Diameter (in) 2.375
Schedule
Wall Thickness (in)
10
20
30
STD 0.154
40 0.154
60
XS 0.218
80 0.218
100
120
140
160 0.344
XXS 0.436
Nominal Pipe Size (in) 2 1/2
Outside Diameter (in) 2.875
Schedule
Wall Thickness (in)
10
20
30
STD 0.203
40 0.203
60
XS 0.276
80 0.276
100
120
140
160 0.375
XXS 0.552
Nominal Pipe Size (in) 3
Outside Diameter (in) 3.500
Schedule
Wall Thickness (in)
10
20
30
STD 0.216
40 0.216
60
XS 0.300
80 0.300
100
120
140
160 0.438
XXS 0.600
Nominal Pipe Size (in) 3 1/2
Outside Diameter (in) 4.000
Schedule
Wall Thickness (in)
10
20
30
STD 0.226
40 0.226
60
XS 0.318
80 0.318
100
120
140
160
XXS
Nominal Pipe Size (in) 4
Outside Diameter (in) 4.500
Schedule
Wall Thickness (in)
10
20
30
STD 0.237
40 0.237
60
XS 0.337
80 0.337
100
120 0.438
140
160 0.531
XXS 0.674
Nominal Pipe Size (in) 5
Outside Diameter (in) 5.563
Schedule
Wall Thickness (in)
10
20
30
STD 0.258
40 0.258
60
XS 0.375
80 0.375
100
120 0.500
140
160 0.625
XXS 0.750
Nominal Pipe Size (in) 6
Outside Diameter (in) 6.625
Schedule
Wall Thickness (in)
10
20
30
STD 0.280
40 0.280
60
XS 0.432
80 0.432
100
120 0.562
140
160 0.719
XXS 0.864
Nominal Pipe Size (in) 8
Outside Diameter (in) 8.625
Schedule
Wall Thickness (in)
10
20 0.250
30 0.277
STD 0.322
40 0.322
60 0.406
XS 0.500
80 0.500
100 0.594
120 0.719
140 0.812
160 0.906
XXS 0.875
Nominal Pipe Size (in) 10
Outside Diameter (in) 10.750
Schedule
Wall Thickness (in)
10
20 0.250
30 0.307
STD 0.365
40 0.365
60 0.500
XS 0.500
80 0.594
100 0.719
120 0.844
140 1.000
160 1.125
XXS 1.000
Nominal Pipe Size (in) 12
Outside Diameter (in) 12.750
Schedule
Wall Thickness (in)
10
20 0.250
30 0.330
STD 0.375
40 0.406
60 0.562
XS 0.500
80 0.688
100 0.844
120 1.000
140 1.125
160 1.312
XXS 1.000
Nominal Pipe Size (in) 14
Outside Diameter (in) 14.000
Schedule
Wall Thickness (in)
10 0.250
20 0.312
30 0.375
STD 0.375
40 0.438
60 0.594
XS 0.500
80 0.750
100 0.938
120 1.094
140 1.250
160 1.406
XXS
Nominal Pipe Size (in) 16
Outside Diameter (in) 16.000
Schedule
Wall Thickness (in)
10 0.250
20 0.312
30 0.375
STD 0.375
40 0.500
60 0.656
XS 0.500
80 0.844
100 1.031
120 1.219
140 1.438
160 1.594
XXS
Nominal Pipe Size (in) 18
Outside Diameter (in) 18.000
Schedule
Wall Thickness (in)
10 0.250
20 0.312
30 0.438
STD 0.375
40 0.562
60 0.750
XS 0.500
80 0.938
100 1.156
120 1.375
140 1.562
160 1.781
XXS
Nominal Pipe Size (in) 20
Outside Diameter (in) 20.000
Schedule
Wall Thickness (in)
10 0.250
20 0.375
30 0.500
STD 0.375
40 0.594
60 0.812
XS 0.500
80 1.031
100 1.280
120 1.500
140 1.750
160 1.968
XXS
Nominal Pipe Size (in) 22
Outside Diameter (in) 22.000
Schedule
Wall Thickness (in)
10 0.250
20 0.375
30 0.500
STD 0.375
40
60 0.875
XS 0.500
80 1.125
100 1.375
120 1.625
140 1.875
160 2.125
XXS
Nominal Pipe Size (in) 24
Outside Diameter (in) 24.000
Schedule
Wall Thickness (in)
10 0.250
20 0.375
30 0.562
STD 0.375
40 0.688
60 0.989
XS 0.500
80 1.219
100 1.531
120 1.812
140 2.062
160 2.344
XXS
Nominal Pipe Size (in) 30
Outside Diameter (in) 30.000
Schedule
Wall Thickness (in)
10 0.312
20 0.500
30 0.625
STD 0.375
40
60
XS 0.500
80
100
120
140
160
XXS
Nominal Pipe Size (in) 32
Outside Diameter (in) 32.000
Schedule
Wall Thickness (in)
10 0.312
20 0.500
30 0.625
STD 0.375
40 0.688
60
XS
80
100
120
140
160
XXS
Nominal Pipe Size (in) 34
Outside Diameter (in) 34.000
Schedule
Wall Thickness (in)
10 0.312
20 0.500
30 0.625
STD 0.375
40 0.688
60
XS
80
100
120
140
160
XXS
Nominal Pipe Size (in) 36
Outside Diameter (in) 36.000
Schedule
Wall Thickness (in)
10 0.312
20 0.500
30 0.625
STD 0.375
40 0.750
60
XS
80
100
120
140
160
XXS
Nominal Pipe Size (in) 42
Outside Diameter (in) 42.000
Schedule
Wall Thickness (in)
10
20 0.500
30 0.625
STD 0.375
40 0.750
60
XS
80
100
120
140
160
XXS

  • STD - Standard
  • XS - Extra Strong
  • XXS - Double Extra Strong