Design and Analysis of Spiral Mandrel Dies for Wire Coating Application

Abstract

Spiral mandrel dies are commonly used for pipe and blown film extrusion. Despite their attractive properties they have not been used for wire-coating applications, because the feeding of the rather large number of spirals led to designs with unacceptably high pressure losses. A design procedure using only a few spiral channels avoids the aforementioned drawbacks and is suitable for wire-coating applications. Backed up by experimental data and a numerical flow analysis, excellent results in terms of concentricity and regularity can be obtained.