... retention, electricinsulation and alkali resistance, these gasket and sealing stuff are essentialto modern machinery, electrical machinery, steamship boiler, electrical ... two type of asbestos fiber yarn, dust free and with dust:Dust free yarn: composed of around 99% asbestos ... available4) Refractoriness: 250 ~ 550°C 5) Refractoriness of dust free asbestos round rope: 480 ~ 550°C6) Thickness: 3 - ...