To deliver on consumer expectations, including lower costs and improved noise behavior, manufacturers are replacing metals used to produce gears with engineering thermoplastics. Compared to metal, these materials offer shorter, more cost-effective production cycles, as well as better noise, vibration and harshness (NVH) characteristics. Advanced thermoplastics are also required to develop very thin and durable gears that fit into miniature appliance designs and are suitable for high torque applications, such as 1,000-watt food processors.
Yet, polyamide 66 and polyoxymethylene (POM), both of which are commonly used to produce appliance gears, are proven to deteriorate under the strain of high torque levels. These materials also provide limited heat resistance, which makes them unsuitable for applications that operate in temperatures above 80°C. These heat levels frequently occur when worm drives designed for high torque and speeds generate significant amounts of frictional heat. Over time, high torque and heat levels typically wear out or deform the teeth of gears made from PA66 and POM, which can cause an appliance to stop working and may result in costly repairs or product recalls that damage your brand’s reputation.
Selecting an insufficient gear material can also drive up the time and costs spent finalizing gear designs, as thinner lighter gears for smaller appliances, typically need to undergo several design iterations before manufacturers can approve them. To ensure gears meet the needs of OEMs and consumers, manufacturers need to select cost-effective materials that provide ample design flexibility and maintain high mechanical strength throughout part lifetimes.
DSM’s Stanyl® PA46 is a market-leading aliphatic polyamide that offers best-in-class mechanical properties at high temperatures. Manufacturers worldwide use the material to produce gears for state-of-the-art appliances, such as blenders, robot vacuum cleaners and washing machines. Stanyl’s inherent high crystallinity provides excellent tensile strength, as well as fatigue, wear and friction resistance required for gears used in small high-speed motors that run at 24,000rpm, and its high flow properties make it ideal for injection molding processes.
Best-in-class mechanical strength
Due to its outstanding tribological properties, Stanyl PA46 is best suited for manufacturing wear and fatigue-resistant gears designed for appliances with long operational lifetimes. Gear load cycle testing conducted in an 80°C environment shows that Stanyl PA46 gears offer 25 to 50% higher torque resistance compared to PA66 and POM alternatives. Its melting temperature of 295°C achieves the best mechanical performance of any high-temperature polyamide when exposed to extreme heat. DSM also offers EcoPaxx®, our leading bio-based thermoplastic optimized for gear applications with stringent moisture uptake and dimensional stability requirements.
Reducing production costs
Stanyl PA46 gears can be made up to 40% lighter than PA66 and POM alternatives without compromising part performance – helping manufacturers save considerable costs and design space. The material doesn’t require expensive wear and friction optimizers to enhance gear strength, and it demonstrates superior torque and durability performance compared to PA66 reinforced with carbon filler. Our advanced gear testers predict how parts will respond to real-life conditions, reducing the risk of parts needing to be re-approved after production, and ensuring our thermoplastic solutions respond to manufacturers’ changing requirements.
DSM works directly with our customers to evolve our engineering materials beyond industry standards. With more than 30 years of commercial use, Stanyl PA46 provides the durability, wear resistance and design flexibility gear manufacturers need to exceed OEM and end-consumer expectations. We offer in-depth material and design support, as well as application-specific expertise, to help you cost-effectively produce gears that help set you apart from your competition, strengthen relationships with your customers, and win new business.