Plymouth, Michigan – New technology from Freudenberg-NOK Sealing Technologies and Solvay Specialty Polymers has enabled production of General Motor’s Hydra-Matic 8L90 8-speed transmission, a powertrain component used in vehicles ranging from the Chevrolet Corvette to the company’s pickup lines.
The High-Load, High-Shear Geared Axial Polymer Thrust Washer (HLHS GAP Thrust Washer), designed to replace thrust washers made of sintered metal or aluminium, was tested and validated to support the auto manufacturer’s launch schedule. Collaboration between Freudenberg-NOK, Solvay, and GM assured the project’s success and earned it finalist honors in the Powertrain category of the 44th annual 2014 Society of Plastics Engineers’ (SPE’s) Automotive Innovation Awards Competition.
“We are pleased that SPE has recognized the HLHS GAP Thrust Washer as a finalist in its Automotive Innovation Awards competition. This project represents a powerful amalgamation of new technology, industry collaboration, rapid customer response and lean manufacturing,” said Dr. Luis Lorenzo, senior vice president, Technology and Innovation, Freudenberg-NOK. “These are, in fact, business attributes that Freudenberg-NOK and Solvay regularly offer customers.”
The HLHS GAP Thrust Washer offers friction and wear properties at elevated pressures and velocities. Freudenberg-NOK and Solvay worked together to design and test a thrust washer using Solvay’s Torlon 4275 polyamide-imide (PAI) resin, a plastic with the highest strength and stiffness of any thermoplastic up to 275°C (525°F). The material offers resistance to wear, creep, and chemicals – including strong acids and most organics – and is suited for severe service environments.
“The HLHS GAP Thrust Washer program provides both a template and benchmark for future component program success and opens opportunities for continued metal replacement in powertrain applications,” said Brian Baleno, global automotive business manager for Solvay Specialty Polymers.
Freudenberg-NOK and Solvay collected broad performance data on Torlon 4275 when developing the thrust washer. Solvay used a six-lot resin testing system to gather information relating to tensile strength, resistance to transmission fluid, and heat aging. In addition, Solvay demonstrated the material’s fit in lubricated friction and wear environments via its proprietary ASTM D3702-based friction and wear test rig.
Freudenberg-NOK used proprietary equipment to test the thrust washer under extreme conditions to provide assurance that the new component met performance requirements. The company’s unique thrust washer machine uses air pressure to apply upwards of 3000 lb of pressure on the washer, and has the capability of spinning at 10,000rpm. The machine also regulates oil temperature, oil flow rate, and runs components at an angular offset thanks to a unique leveling platen.
“OEM vehicle manufacturers seeking to replace traditional metal components with new thermoplastic designs must have assurances that new materials can be designed, validated, and produced to meet weight and extended performance requirements while also addressing fundamental issues such as cost, quality, delivery, and manufacturability,” said Rory Pawl, sales director, Process Seals, and former director, Future Technology, Freudenberg-NOK.
Freudenberg-NOK is producing the HLHS GAP Thrust Washer in Findlay, Ohio, using its single-cavity, net-shape molding process. The process, which uses compact, custom-engineered one-cavity injection molding machines, improves part quality and reduces engineered waste, scrap, and costs.
“We have set a benchmark with this component and this project,” Pawl concluded. “As growing demands for better fuel economy, lower emissions, tighter packaging and longer component life drive manufacturers to explore new powertrain performance options, we are ready to assist them with superior solutions.”
Source: Freudenberg-NOK