Heathcoat Fabrics, based in Tiverton in Devon, manufacture and supply world class products to exacting standards and which often involve complex challenges. Heathcoat supply the Aerospace, Automotive, Defence, Healthcare, Emergency services and niche specialist critical fabric applications. Part of their finishing process requires slitting efficiently at speed and importantly, for many materials, cutting and sealing the edges of various thermoplastic based fabrics to prevent fraying, making them ready for post processing by the customer.
The ultrasonic cut’n’seal process has proven to be a perfect fit for this type of application. The ultrasonic head works in conjunction with a rotary anvil wheel which is used to trap the continuously moving fabric at a pinch point, aiding the wheel slitting edge to achieve faster cut speeds. Heathcoat take advantage of this technology when processing a number of challenging woven and knitted technical materials such as woven Meta Aramid and in the case of more standard thermoplastic woven and knitted polymers, to seal the edge either side of the cut by a local melt of the fabric thermoplastic content.
The technique, although well established at Heathcoat, has required improvement upgrades on older existing slitting installations and has now been explored further with Telsonic in the evaluation of additional applications. This has culminated in a further four new locally fitted Telsonic slitting head systems within a new stenter machine delivered into Heathcoat from textile machinery specialist Brückner of Germany. This brings the total number of Telsonic slitting head systems in use at Heathcoat to eleven.
(Telsonic’s ultrasonic technology delivers accurate cutting and sealing of woven and non-woven fabrics in a continuous operation, offering high cutting speeds and sealed cut edges)
Developing Additional Applications
Telsonic UK conducted extensive continuous cut’n’seal trials at the company’s Poole laboratory. These trials included various fabrics ranging from specialist woven Meta Aramid nylons and a range of specialist materials involving standard nylons, Polypropylene and Polyesters at various densities from 40 to 120gsm. The objective was to establish material dependant cutting speeds and sealed edges, ranging from 20 to 80m/min for core products and also challenge the technology with extremely fast slitting speeds of over 200m/min for parachute material. With successful outcomes of appropriate ultrasonic process parameters and cutting anvil slitting edge configuration, the trials proved Telsonic’s technology and capabilities in both the delivery of the process and its robustness over the full range of applications.
Telsonic UK’s cut’n’seal solutions, in full production at Heathcoat, utilise Telsonic’s MAGW02012E fully housed generators for continuous run application, with analogue inputs controlled from the machine HMI for speed dependant amplitude output. These in turn power the SE2012S converter with cooling cap, titanium booster & Zapp hardened steel round sonotrode with chilled air cooling of the sonotrodes. The sonotrodes are tuned to low frequency and the boosters are the round type indexable to provide extended wear life at the sonotrode face, allowing re-grinds.
(Telsonic’s cut ‘n’ seal solutions are now in full production at Heathcoat) Telsonic’s reputation within the Industry, their experience in the continuous cut’n’seal process, together with the proven reliability of Telsonic’s hardware, were key factors in the company being chosen for this project. The performance of Telsonic’s converters, which are a crucial element in this continuous run application, combined with Zapp steel one piece tooling further reinforced Heathcoat’s confidence in the solution being proposed Telsonic UK offer a comprehensive range of ultrasonic modules and systems for a variety of food cutting, plastic welding, cutting, sealing, cut’n’seal, metal welding, packaging, sieving, and cleaning applications within a wide range of industries.
