9.5.4. Determining the inside diameter di of the pipe by calculation

The following approach formula can be used to dimension the inside diameter of the pipe. It assumes the maximum operating pressure p max (compressor cutout pressure ), the maximum volume flow ( required output L B ) and the effective pipe length L. Dp is the target pressure loss. di = Inside diameter of pipeline [m] = Total volume flow [m³/s] L = Effective pipe length [m] Dp = Target pressure loss [bar] pmax = Compressor cut-out pressure [barabs]

= 2 m³/min = 0,033 m³/s L = 200 m Dp = 0,1 bar pmax = 8 barabs

Example The inside pipe diameter d i of a pneumatic connection line with a target pressure loss Dp of 0,1 bar is to be determined using the approach formula. The maximum operating pressure p max (compressor cutout pressure) is 8bar abs . A volume flow of 2 m³/min will flow through pipeline with an approximate length of 200 m. The inside diameters of pipes are standardised in certain sizes. But it is rare to find a standard nominal width that matches the calculated inside diameter. In such cases the next largest standard nominal width is taken.

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[last chapter]
. . 9.5. Dimensioning pipelines
. . . . 9.5.1. Maximum pressure drop Delta p
. . . . 9.5.2. Nominal width of pipelines Comparison [DN - Inch ]
. . . . 9.5.3. Equivalent pipe length
. . . . 9.5.4. Determining the inside diameter di of the pipe by calculation * You are here *
. . . . 9.5.5. Determining the inside diameter of the pipe di by graphics
. . . . 9.5.6. Determining the inside diameter of the pipe di with the aid of a bar graph
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