The Spiral Mandrel Geometry

The axial groove width B is related to the perpendicular groove width W by the following relationship  

A similar relationship is valid for the axial flight width. The tangential flight and channel width, W/sincp and w/sincp, are related to the mandrel diameter D and the number of flights N by the following expression  

The groove depth can be expressed as a function of helical distance z by the following relationship  

With these expressions a complete analysis of the flow process in the spiral mandrel section can be made. 

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