Groove Geometry Calculation


Given the groove internal angle and depth, and the tube diameter and target span angle, this page presents a method of calculation to determine the central angle for each groove and the number of grooves required to completely cover the target area.

Fig 1 - Calculation trigonometry

In Fig 1 the tube surface (before grooving) and the groove are shown in red, and the center of the tube (coincident with the focus) is shown in green.

Once the groove half-width, w, has been determined, it can be used in conjunction with the tube radius, r, to determine the central angle for a groove.

The number of grooves required can then be determined by dividing the target span angle by the groove central angle.

The following C program performs these calculations and displays the input parameter values and the calculated results:

Download executable MS-DOS version

Copyright © 2009 Morris R Dovey

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