Plastic welding technology offers the medical device industry precision, cleanlines and the high speed to produce the latest high-performance products. However, small, highly-intricate plastic components for medical devices have been a challenge to assemble because of their size and complexity.
One of the latest developments in plastic joining for the medical market comes from Forward Technology which recently released its next-generation HS-OSW (High Speed Orientating Spin Welder). This new welder provides enhanced pneumatic process control and an intelligent servo drive controller for spin welding of small, high-precision medical components.
According to Forward, very small fittings, adaptors and tubular connectors as small as 3mm can be spin welded with a high degree of repeatable precision. A successful and consistent spin welding process involving smaller spin welding applications often requires a controllable degree of finesse to bring the components gently together. This is followed by a shift of process variables to deliver the appropriate rotational speed, weld pressure, and torque to reliably and consistently assemble the application.
A key process control feature of the HS-OSW which provides the finesse for spin welding small and delicate applications is the dual-speed vertical head velocity control and proportional valve. It offers variable pressure control through the various stages of the spin welding process. The user may select individual pressure settings for head down speed, contact pressure, weld pressure, and cooling pressure which, says Forward, will result in greatly improved process control and improved weld cycle times. This capability reduces cycle time by 20% compared with standard single-pressure servo models and also improves repeatability.
Small-diameter spin welding applications manufactured from commonly used medical grade polymers such as polyethylene (PE), acrylic, polypropylene (PP), polycarbonate (PC), nylon, and acrylonitrile-butadiene-styrene (ABS) benefit from the additional process control features of the HS-OSW. The ability to gently bring parts together at one pressure setting and then welding at another higher pressure setting aims to facilitate the optimisation of weld strength while minimising weld particulate and weld flash.
The modular design of the HS-OSW allows for integration of multiple weld heads into an automated rotary or in-line production system. Ethernet connectivity facilitates development of multiple head welding systems utilising two, four, or even eight weld heads and provides the means for weld data collection, weld process monitoring, and tracking of product throughout an automated production system that may include secondary operations such leak testing and part marking.