TPi May 2017

New tube cutting technology meets next generation production needs By Geoff Shannon, Amada Miyachi America, and David Van de Wall, Amada Miyachi Europe

Laser The pulsed Nd:YAG lasers used in the past have been superseded by fibre lasers with better beam quality that does not change with pulse energy and average power. This provides a smaller and more consistent focused spot size, which offers tighter cutting tolerances and, with spot sizes down to 10 microns, the ability to cut much finer detail features. These lasers provide pulse frequencies up to and beyond 5 kHz and pulse widths down to 20 microseconds (µs) to enable energy input optimisation for a wide variety of tube materials and wall thicknesses. Higher frequencies can be implemented to maximise acceleration and speed for a range of part thicknesses. From an operational standpoint, the fibre lasers have a number of advantages. They are air cooled, run off single-phase 240V electrical power, and have diodes with lifetimes that are greater than 70,000 hours, which equates to minimal operational costs. Figure 2 shows an example of a tube produced by one of the new laser tube cutters on the market (left) and a close-up of laser tube cutting (right). Fibre lasers use microsecond pulses and offer a cutting speed and edge quality that is sufficient for many applications. The femtosecond (fs) laser offers laser pulses that are under 400x10 -15 seconds (s), or about one million times shorter than the fibre laser. The very short pulse duration, combined with

Replacing legacy cutting systems The pulsed neodymium-doped yttrium aluminium garnet (Nd:YAG) lasers used in the past two decades have definitely been great workhorses. They have performed well and been excellent manufacturing centres for many companies. Unfortunately, the original integrated pulsed Nd:YAG lasers that remain in operation are now obsolete and difficult to service. While many of these systems have been upgraded to fibre lasers, they still have old stage sets that are a number of generations behind current technology. In addition, they are running on slow and ageing controllers with legacy software. Simply put, the laser, stages, controller, software, water systems and automated tube loader technology have all moved on. Here is a brief overview of improvements in these components that enable faster and better cuts with higher production rates and less down time. S tents and tubes are used in countless medical devices and new ones are being added every day, fuelled in part by the growth of minimally invasive surgery and the commonplace use of stents. The sheer number and diversity of devices is rapidly increasing, and with it the demand for more and more laser cut stents: flexible tubing, cannulas and micro cannulas, needles, biopsy devices and other minimally invasive tools. Figure 1 shows examples of common features in modern stents. While legacy stent and tube cutting systems have performed well during recent decades, new cutting technologies coming onto the market offer faster and better cuts, with higher production rates and new and unique cutting capabilities.

Figure 1: Modern stents

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TUBE PRODUCTS INTERNATIONAL May 2017

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