Threaded insert

self-tappingpress-inmetal

Threaded Inserts for Plastics Threaded Inserts for Plastics provide reusable threads and preserve the bolted joint integrity for the life of the application. Since an Insert is generally twice the diameter of a screw, the shear surface is increased fourfold, thereby significantly enhancing the load carrying ability of the bolted plastic joint as compared to one without the use of a metal Threaded Insert. Threaded Inserts for Plastics also allow the appropriate installation torque to be applied to the screw without stripping the threads that would otherwise occur if the screw was installed directly into the plastic. In addition, the metal thread of an Insert provides permanent creep resistance for the entire load path of the thread to prevent loosening and maintain a durable tightly threaded connection. The two main categories of plastics suitable for Threaded Insert installation are thermosets and thermoplastics. Thermoset plastics, once formed, undergo an irreversible chemical change and cannot be reformed using heat and pressure. These plastics are tough and heat-resistant. Examples of thermosets are Bakelite, epoxies, urea and polyester resins. Heat/ Ultrasonic Inserts are not suitable for thermosets since this type of plastic can not be reformed. Thermoset plastics require the use of Moulded-In, Press-In, or Self-Tapping Inserts. Thermoplastics are rigid and solid at normal temperatures, and at elevated temperatures they soften and melt. Some of the more common thermoplastics are ABS, polyamide (eg. Nylon 6-6), PVC and polycarbonate (PC). Press-In, Self-Tapping, Heat / Ultrasonic and Moulded-In Inserts are suitable for plastics in this category.