We’ve spent a lot of time this past year talking about our medical tube cutting capabilities, and, as you might guess, we’ve been getting a lot of calls on the subject. Let me start by saying that successful thin wall metal tube cutting is all about the results: excellent precision, superior edge quality, and tight dimensional tolerances - and so it makes sense that our customers and prospects are concerned about getting the “perfect” laser for the job. Achieving these precision cuts, however, isn’t all about the laser – it’s more about its successful integration into a complete system.
What exactly does this integration entail? Well, to start, in addition to the “perfect laser,” each application requires a workstation, focusing optics, assist gas, a motion package with programmable motion, full-featured control software with post processor capability and a user friendly and intuitive interface. Integrators need to develop an entire system in which all of these elements work together to achieve the necessary cut quality, production throughput and minimal downtime.
To help with this process, we’ve put together 5 tips regarding these elements and the considerations involved in integrating them:
- Enclosure and CNC motion options: Laser cutting applications are usually conducted inside a Class I eye-safe enclosure. These enclosures must meet the FDA’s CDRH (Center for Devices and Radiological Health) and ANSI (American National Standards Institute) Z136.5 Class I safety standards for high power laser systems. These standards include redundant safety interlocks on the access doors, appropriate power density in the viewing windows, warning labels, an emergency stop, and indicator lights. There are further regulations as to the platform size and stability, which you can find in the LIA’s guide to ANSI standards and at the OSHA website.
- Two dimensional tube cutting: Tube cutting requires precision, multi-axis programmable CNC linear and rotary motion. A fully programmable tube feeder (capable of accommodating up to 10-foot long metal tube sections), is typically used in conjunction with a 3-4 axis CNC motion package for two dimensional cutting of open end tube components. When the laser cut cycle is initiated, the feeder automatically advances the exact amount of tube material into the laser cutting position. A rotary collet grips and turns the tube while the laser makes the necessary cuts and part features. The feeder reduces labor and maximizes productivity, since no human intervention is required until the entire 10 foot length of tube is consumed.
- Three dimensional tube cutting: Laser cutting of closed-end tubular components such as laparoscopic medical instruments requires a 5-axis CNC motion package, usually consisting of 3 linear and 2 rotary axes. The process is a bit more labor intensive, because these components are generally pre-cut to their finished length before processing, making it necessary to manually load and unload parts., though robotic loading can also be used.
- CAD design and post processing software: Complex laser cutting operations require full-featured programming software for controlling the laser parameters and precision motion functions. This is achieved by transferring a digital 3-dimensional CAD model to a computer with post processing software that generates the tool path instructions and functions for the laser and motion system to complete the actual part. A graphic user interface flat panel display provides the operator with a full suite of controls for laser process settings and CNC motion programming. The programming software also provides tools for gathering and storing process data to meet FDA validation and in-house documentation requirements. Programming and external communication is provided via a dedicated PC and Ethernet connectivity.
- Post Installation Support: After the system has been installed there may be requirements for additional training on the system or application. And almost every system will need some service or maintenance now and again. It is extremely advantageous, therefore, for the system integrator to be the “single source” to call for all of these services to ensure they are fixed fast and efficiently.