Formation of Inner Spiral Multi-Grooved Tube by Hot Extrusion

Abstract

The spiral extrusion processing method that forms an inner spiral multi-grooved tube by hot extrusion is proposed. The spiral extrusion processing method is a compound die extrusion method that installs a rotary plug at the exit of the die mandrel of porthole dies. In this paper, the effects of extrusion conditions and rotary plug shape on groove torsion angle, section groove angle and groove depth in the inner spiral multi-grooved tube are investigated. As a result, a good inner spiral multi-grooved tube is formed in which extrusion temperature and extrusion ram speed are low. Even if the working height of the rotary plug increases, only the outer diameter of the extruded inner spiral multi-grooved tube increases, and therefore, it is understood that the predetermined inner spiral multi-grooved tube is not provided.