Edwards Lifesciences is a worldwide leader in the production and research of cardiovascular equipment and solutions, including replacement heart valves, cannulae, and tools designed for minimally invasive heart surgery. The femoral line in their production scheme produces products specifically designed for access through the femoral artery. One process in the femoral line that currently limits output efficiency is the cutting of wire wound cannulae to specified lengths. This task is performed manually with a razor blade and wire cutters. There is a significant amount of rework associated with this process that limits output to about one third of what it could be. Edwards Lifesciences has asked a team of BYU students to create an automated process to consistently cut wire-wound cannulae and prepare the ends for joining by radio-frequency welding, to decrease rework and cycle time while maintaining medical quality.

The design the team has developed is a semi-automated, two-step cutting process, similar to what is currently done by hand at Edwards. The cannula is fixed in a positioning setup by the operator, which specifies accurately the final cut length of the cannula. Once the start button is pressed, the cannula is rotated about its axis by a servomotor and gear train while a razor blade is pressed against it, cutting the plastic. A pneumaticlly actuated torsion spring punch then actuates, shearing through the wire and finishing the cut. The team was successful in designing an effective solution that will cut more cannulae every day and allow Edwards to meet the growing demands for femoral catheters.