Tube vs. Pipe: The Tube is manufactured to a set outside diameter and a wall thickness (e.g. 1.5"OD, 0.065" wall), while a Pipe is specified by a "nominal" (not actual) inside diameter. The wall thickness of pipe is described by the "schedule". For example, schedule 5 and 40 pipe have wall thicknesses of 0.065" and 0.109" respectively.

Standard Specification for Seamless and Welded Austenitic Stainless Steel Pipes
(ASTM A312, A358, A376/ASME SA312, SA358, SA37)
Nominal
Pipe Size
Pipe ODPipe Schedule
5S 10S 40S 80S
(inches)(inches)Wall thk
[ID]
(in)
Weight
(lb/ft)
Wall thk
[ID]
(in)
Weight
(lb/ft)
Wall thk
[ID]
(in)
Weight
lb/ft
Wall thk
[ID]
(in)
Weight
(lb/ft)
1/80.405 - - 0.049 0.1363 0.068 0.2447 0.095 0.3145
1/40.540 - - 0.065 0.3297 0.088 0.4248 0.119 0.5351
3/80.675 - - 0.065 0.4235 0.091 0.5676 0.126 0.7388
1/20.840 0.065 0.5383 0.083 0.6710 0.109 0.8510 0.147 1.088
3/41.050 0.065 0.6838 0.083 0.8572 0.113 1.131 0.154 1.474
11.315 0.065 0.8678 0.109 1.404 0.133 1.679 0.179 2.172
1-1/4 1.660 0.065 1.107 0.109 1.806 0.140 2.273 0.191 2.997
1-1/2 1.900 0.065 1.274 0.109 2.085 0.145 2.718 0.200 3.631
22.375 0.065 1.604 0.109 2.638 0.154 3.653 0.218 5.022
2-1/22.875 0.083
[2.709]
2.475 0.120
[2.635]
3.531 0.203
[2.469]
5.793 0.276
[2.323]
7.661
33.500 0.083
[3.334]
3.029 0.120
[3.260]
4.332 0.216
[3.068]
7.576 0.300
[2.900]
10.25
3-1/24.000 0.083
[3.834]
3.472 0.120
[3.760]
4.973 0.226
[3.548]
9.109 0.318
[3.364]
12.51
44.500 0.083
[4.334]
3.915 0.120
[4.260]
5.613 0.237
[4.026]
10.79 0.337
[3.826]
14.98
4-1/25.000 - - - - 0.247
[4.506]
12.54 0.355
[4.290]
17.60
55.563 0.109
[5.345]
6.349 0.134
[5.295]
7.770 0.258
[5.047]
14.62 0.375
[4.813]
20.78
66.625 0.109
[6.407]
7.585 0.134
[6.357]
9.289 0.280
[6.065]
18.97 0.432
[5.761]
28.57
77.625 - - - - 0.301
[7.023]
23.54 0.500
[6.625]
38.04
88.625 0.109
[8.407]
9.914 0.148
[8.329]
13.40 0.322
[7.981]
28.55 0.500
[7.625]
43.39
99.625 - - - - 0.342
[8.941]
33.91 0.500
[8.625]
48.73
1010.750 0.134
[10.482]
15.19 0.165
[10.420]
18.70 0.365
[10.020]
40.480.500
[9.750]
54.74
1111.750 - - - - 0.375
[11.000]
45.56 0.500
[10.750]
60.08
1212.750 0.156
[12.438]
21.07 0.180
[12.390]
24.16 0.375
[12.000]
49.56 0.500
[11.750]
65.42

ASTM A270: Specification for Seamless and Welded Austenitic Steel Sanitary Tubing
Sanitary Flange Dimension Guide
ferrule profile
SizeOD
Inch
ID (Bore)
Inch
Wall Thk.
Inch
F-OD
Inch
G-DIA
Inch
A
Inch
B
°
C
Inch
D
Inch
E
°
F
Inch
G
Inch
H
Inch
1/20.500.3700.0650.9920.8590.14300.0450.08445°0.0310.030
3/40.750.6200.0650.9920.8590.14300.0450.08445°0.0310.030
11.000.8700.0651.9841.7180.110520°0.0450.06246°0.0470.031
1-1/21.501.3700.0651.9841.7180.110520°0.0450.06246°0.0470.031
22.001.8700.0652.5152.2180.110520°0.0450.06246°0.0470.031
2-1/22.502.3700.0653.0502.7810.110520°0.0450.06246°0.0470.031
33.002.8700.0653.5793.2810.110521.25°0.0450.06246°0.0470.031
44.003.8340.0834.8624.3440.110521.25°0.0450.06246°0.0470.031
55.004.7820.1095.6875.2920.110521.25°0.0450.06246°0.0470.031
66.005.7820.1096.5706.1560.21800.0600.08046°0.0470.031
88.007.7820.1098.5708.1560.21800.0600.08046°0.0470.031
1010.009.7600.12010.57010.1560.21800.0600.08046°0.0470.031
1212.0011.7600.12012.57012.1560.21800.0600.08046°0.0470.031
  • Sanitary tubes are sold mostly in 304L, 316L & AL-6XN Steel.
  • Typical Finishes are: No. 1-Industrial, No. 3-Sanitary, No. 5-Industrial, and No. 7-Sanitary.
  • Typical Gasket Materials are: Buna-N, Teflon®, Silicon, Viton and EPDM.
  • For detail information about Sanitary Machine Design Standards visit 3-A Sanitary Standards, Inc.
  • Alfa Laval, US is a supplier of parts for heat exchangers and other industrial applications.
  • Andron Stainless Corp. is a supplier of valves, tubing and fittings.
  • VNE Stainless is a supplier of valves, tubing and fittings.

NPT (National Pipe Taper) threads are used to create a dry seal between the joints as a larger diameter is forced into a smaller one. Teflon Tape should be used to complete the seal. NPS (National Pipe Straight) threads are used to acomodate the use of nuts in the joint and an o-ring might be needed to secure the seal. Both NPT and NPS have the same thread angle, shape, and pitch. While NPT and NPS threads will engage, they do not seal properly with each other.

BSPT (British Standard Pipe Taper) is similar to NPT except for one important difference. The angle across the flanks of threads is 55 degrees instead of 60 degrees as it is for NPT. Thus an NPT male will fit into a BSPT fitting or vice versa but they will not seal. BSPP (British Standard Pipe Parallel) is most popular in the UK, Europe, Asia, Australia, New Zealand and South Africa. It is a parallel thread fitting that uses a bonded seal ring to do the sealing.

National Standard Taper Pipe Threads Size NPT Chart
npt pipe thread
Outside Diameter D
Nominal Pipe Size
Threads per Inch (Pitch)
Thread Pitch Length, P
Pitch Diameter at External Thread Start E0
Hand Tight Thread Engagement
Length, L1
Diameter E1
Maximum Thread Engagement L2
Diameter E2
0.3125
1⁄16
27
0.03704
0.27118
0.160
0.28118
0.2611
0.28750
0.405
1⁄8
27
0.03704
0.36351
0.1615
0.37360
0.2639
0.38000
0.540
1⁄4
18
0.05556
0.47739
0.2278
0.49163
0.4018
0.50250
0.675
3⁄8
18
0.05556
0.61201
0.240
0.62701
0.4078
0.63750
0.840
1⁄2
14
0.07143
0.75843
0.320
0.77843
0.5337
0.79179
1.050
3⁄4
14
0.07143
0.96768
0.339
0.98887
0.5457
1.00179
1.315
1
11 1⁄2
0.08696
1.21363
0.400
1.23863
0.6828
1.25630
1.660
1 1⁄4
11 1⁄2
0.08696
1.55713
0.420
1.58338
0.7068
1.60130
1.900
1 1⁄2
11 1⁄2
0.08696
1.79609
0.420
1.82234
0.7235
1.84130
2.375
2
11 1⁄2
0.08696
2.26902
0.436
2.29627
0.7565
2.31630
2.875
2 1⁄2
8
0.12500
2.71953
0.682
2.76216
1.1375
2.79062
3.500
3
8
0.12500
3.34062
0.766
3.38850
1.2000
3.41562
4.000
3 1⁄2
8
0.12500
3.83750
0.821
3.88881
1.2500
3.91562
4.500
4
8
0.12500
4.33438
0.844
4.38712
1.3000
4.41562
5.563
5
8
0.12500
5.39073
0.937
5.44929
1.4063
5.47862
6.625
6
8
0.12500
6.44609
0.958
6.50597
1.5125
6.54062
8.625
8
8
0.12500
8.43359
1.063
8.50003
1.7125
8.54062
10.750
10
8
0.12500
10.54531
1.210
10.62094
1.9250
10.66562
12.750
12
8
0.12500
12.53281
1.360
12.61781
2.1250
12.66562
14.000
14
8
0.12500
13.77500
1.562
13.87262
2.2500
13.91562
16.000
16
8
0.12500
15.76250
1.812
15.87575
2.4500
15.91562
18.000
18
8
0.12500
17.75000
2.000
17.87500
2.6500
17.91562
20.000
20
8
0.12500
19.73750
2.125
19.87031
2.8500
19.91562
24.000
24
8
0.12500
23.71250
2.375
23.86094
3.2500
23.91562

fittings
Pneumatic Parts Reference
  1. Pneumatic Cylinder: The main features to consider are bore size, stroke and air port size.
    • Vendors: SMC, MSC, Parker, ASCO Numatics, Hydro Air Hughes, Airline Hydraulics
    • [aa] Rod threads (English): 1/4-28, 5/16-24, 3/8-16, 7/16-20, 1/2-13, 1/2-20, 5/8-11, 3/4-10, 1-8
    • [aa] Rod threads (Metric): M8x1.25, M10x1.25, M14x1.5, M18x1.5, M22x1.5, M26x1.5
    • [bb] Mount threads (English): 3/4-16, 1-14, 1.0625-18, 1.25-12, 1.375-12, 1.75-12
    • [cc] Port Sizes (English): 1/8-27, 1/4-18, 3/8-18, 1/2-14
    • [cc] Port Sizes (Metric): M5x0.8, M6x0.75, M8x1.0, M10x1.25, M12x1.25, M14x1.5

  2. Elbow Fitting: One of many Push-to-Connect fittings available for pneumatic assemblies.
    • Vendors: SMC, McMaster-Carr, AutomationDirect, Airline Hydraulics
    • Thread-to-Hose Sizes: 1/8 NPT- 1/4, 1/8 NPT-5/16, 1/8 NPT-3/8
    • Thread-to-Hose Sizes: 1/4 NPT-5/16, 1/4 NPT-3/8, 1/4 NPT-1/2

  3. Nylon Air Tubing: Suitable for general-purpose applications up to 220 psi (-40 to 140 °F)
    • Vendors: SMC, PolyConn, AutomationDirect, Airline Hydraulics
    • OD sizes: 5/32, 5/16, 1/8, 3/16, 1/4, 3/8, 1/2
    • Available colors: Blue, Black, Green, Orange, Red, Yellow, White

  4. Bulkhead Union: Suitable for pneumatic assemblies that include a components enclosure

  5. Enclosure: To house sensitive components in pneumatic or electrical assemblies

  6. Straight Fitting: One of many Push-to-Connect fittings available for pneumatic assemblies.

  7. Air Valve: 4-Way, solenoid, pilot actuations. Flows of 27-63 SCFM
    • Vendors: AROzone, MSC Industrial
    • Port sizes (NPT): 1/8, 1/4, 3/8

  8. Brass Muffler: Mufflers are used to reduce noise and to guard the exhaust outlet.

  9. Bulkhead Adaptor: This design join tubes and NPT fittings through an enclosure wall.

  10. Plastic Muffler: Mufflers are used to reduce noise and to guard the exhaust outlet.

  11. Coupler Plug: To connect with standard shop or factory air lines.

  12. Wire Grip Bulkhead Connector: To run cables through enclosure walls.


fittings
  1. Tubes/Hoses of Polyurethane, Nylon, Silicon Rubber are available in Misumi USA, McMaster-Carr, etc.
  2. Push-to-Connect are available in Misumi USA, McMaster-Carr, etc.
  3. Reducing bushings are available in Misumi USA, McMaster-Carr, etc.
  4. Butt-Weld adapters can be found at McMaster-Carr.