Non-isothermal simulation of a two-lumen catheter tubing extrusion for a die design

Catheter tubing is manufactured by an extrusion process. In this study, two types of extrusion dies that were used in catheter tubing extrusion were compared through non-isothermal computer simulation. The two types of dies were a straight die and a crosshead die. The straight die is attached to the extruder in the same line while the crosshead die is attached to the extruder at a right angle. The pressure distribution, velocity distribution, temperature distribution, and shear stress distribution in the two types of dies were analyzed and compared through computer simulation. Flow characteristics and temperature stabilities were examined and subsequently the adequacy of extruders for the two dies was discussed. The straight die had the advantage of a smooth and balanced flow, while the crosshead die had the advantage of a low shear stress generation that influenced the tubing quality.