Nominal Tube Dimensions Chart (BWG)
Smaller gauge numbers mean thicker walls.
The Birmingham Wire Gauge (BWG) Chart is a standardized reference for the wall thickness of tubes in industrial applications. Crucial for manufacturing, heat exchangers, and piping systems, it translates standard gauge numbers into precise decimal inch dimensions, and shows the resulting tube I.D. for each O.D.
Tube I.D. by O.D. & Gauge
Each cell is the tube I.D. in inches. Scroll the chart sideways to see every gauge.
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