Engineering ToolBox - Resources, Tools and Basic Information for Engineering and Design of Technical Applications!

Pipes and Tubes - Imperial vs. Metric Sizes

SI vs. Imperial pipe sizes.

The United States is the only major industrial country where inch sizes are commonly used.

Pipes and Tubes - Imperial vs. Metric Sizes
Nominal Imperial Pipe Size
(NPS)
Nominal Metric Pipe Size
(DN)
ASHRAE
(mm)
AWWA
(mm)
NFPA
(mm)
ASTM
copper tube
(mm)
1/8 6 6
3/16 8 8
1/4 10 8 10
3/8 12 10 12
1/2 15 15 12.7, 13 12 15
5/8 18 18
3/4 20 20 22
1 25 25 25 25, 25.4 28
1 1/4 32 32 33 35
1 1/2 40 40 45 38, 38.1 42
2 50 50 50, 50.8 51 54
2 1/2 65 65 63, 63.5 63.5, 64 67
3 80 80 75 76, 80 79
3 1/2 90 89
4 100 100 100 102 105
4 1/2 115 114.3
5 125 127 130
6 150 150 150 152 156
8 200 200 200 103 206
10 250 250 250 257
12 300 300 300 305 308
14 350 350
16 400 400
18 450
20 500 500
24 600 600
28 700
30 750
32 800
36 900
40 1000
44 1100
48 1200
52 1300
56 1400
60 1500

Related Topics

Related Documents

Search

Search is the most efficient way to navigate the Engineering ToolBox.

Engineering ToolBox - SketchUp Extension - Online 3D modeling!

3D Engineering ToolBox Extension to SketchUp - add parametric components to your SketchUp model

Add standard and customized parametric components - like flange beams, lumbers, piping, stairs and more - to your Sketchup model with the Engineering ToolBox - SketchUp Extension - enabled for use with older versions of the amazing SketchUp Make and the newer "up to date" SketchUp Pro . Add the Engineering ToolBox extension to your SketchUp Make/Pro from the Extension Warehouse !

Translate this Page

Translate this page to Your Own Language .

About the Engineering ToolBox!

Privacy Policy

We don't collect information from our users. More about

We use a third-party to provide monetization technologies for our site. You can review their privacy and cookie policy here.

You can change your privacy settings by clicking the following button: .

Citation

This page can be cited as

  • The Engineering ToolBox (2020). Pipes and Tubes - Imperial vs. Metric Sizes. [online] Available at: https://www.engineeringtoolbox.com/imperial-si-metric-pipe-sizes-d_2181.html [Accessed Day Month Year].

Modify the access date according your visit.

3D Engineering ToolBox - draw and model technical applications! 2D Engineering ToolBox - create and share online diagram drawing templates! Engineering ToolBox Apps - mobile online and offline engineering applications!

Unit Converter

















































3.27.8

.