Thrust-ring components in heavyduty vehicle transmissions are now molded from a high-performance polyetheretherketone
(PEEK) compound by Minnesota Rubber/QMR Plastics, Minneapolis, (www.mnrubber.com). The PEEK parts show less surface abrasion and provide longer service life than the aluminum components they replace.
During operation, thrust-ring components act as rotating planetary carriers for helical ring gears in transmissions. Load forces generate heat, potential wear, and abrasion. With the polymer design, thrust ring durability increased significantly while performance was unaffected. According to Minnesota Rubber/QMR Plastics, the compound includes a high percentage of PEEK for its 400 to 450°F (204 to 232°C) temperature resistance, carbon fiber for wear resistance, and PTFE ( polytetrafluoroethylene) for low friction.
The polymer thrust-ring component also eases assembly. The previous aluminum component had two locating holes that needed rivets. They required accurate alignment to avoid wasted components and poor performance.
In contrast, the polymer component has self-aligning extensions at each end that press-fit quickly and accurately into the ring gears. Potential alignment issues were eliminated, along with scrapped components.