US Patent 7143496 Hot runner nozzle with removable tip and tip retainer

An injection molding apparatus has at least a nozzle having a nozzle body and a nozzle tip. A securing device is used to secure the nozzle tip to the nozzle body via non-metallic threads or threads having a non-metallic coating that mate with complementary threads on the nozzle body. In this example, through use of the non-metallic threads or threads having a non-metallic coating, the securing device has a longer life than conventional securing devices that were made from steel or titanium by eliminating or substantially reducing thread galling.